Tr

'2.1ocur,en

ASSISTANCE TO LAND USE PLANNING

ETHIORIA

GEOMORPHOLOGY AND SOILS

Report prepared forthe Gov,a of Ethiopia

the Food and Agriculturof the United Nationsacting as eTting agency for

the United Nations aavelopment Programme

based on the work ofB.L. Henricksen, S. Ross, Shltan Tilimo

and HY Wijntje-',1

UNITED NATIONS P'LisciL.:iEf-J PP.00,L

FOOD AND AGRICULTUE !--21JIN OF JNhED RATIONS

ùIS ABABA, 1904

AGUA: ETH/78/003

FIELD DOCUMENT 3

This field document ore of a series ofduring the course of thE, L2P project idenWied on the titlepage. The conclusions ano

appropriate at the tiein the light of furcarproject.

The de,luations tien of the -rialin this docum .,,Jhatseever on theculture0- Ltion of the leoal ar ronstit tistatus of ny cont terrftory or era, or concerniym thedelimitation of fr ers,

adation* are thoseThey

considered.

,he-

iii

FAO. Assistance to Land USE; ihig, Ethiopia. Geomorpho ogy

and Soils, Based on the work cif ' enricksev;, S. oss, Sultan Tilimo

and H.Y. Wijntje Bruggeman, 1984. P 425, 17 Figure, 4 TableS

supplement including 8 sheets .:rW legend, AG:DP/ETH/78/003,

Field Document 3.

ABSTRACT

This report describes the :laton of a 1:1 OG 000 seal

Geomorphology and Soils map of Ethiopia, used in the cevelopment of a

master land use plan for the country.

geomorphologi'cal interpretation of 71 frases of Landsat imagery

was maoe, combined with field examination of existing data,

Soils informtion is based e '4- ofavailatie surveys, field

traverses, Landsat derived data tic infbrmation. These data

were combined, as land p units, in a......jJHL dgy and Soils map at

1:1 000 000 scale with extended legend. e FAO sstem of classification

is used in the description of soli AoF.,..Amately 380 landscape

units are described and mapFed. Fnr ,e unit significant landfacets (those covering over T. ,cr.s the are describd, but

are no t mapped. This map effectiv, updates the /Unesco Soil Tnp oi

the World for the section covarIng EtMopia. A general description of

the' tr;sical environment of Ethiopia, in relation to soil forminn processes,

is included, Cross-sections of 1andscape units and tables of related soil

associations arranged by land -acet are brovided, together with annotated

plates deriven YOM ianosat of the image signatures of selected

landscape units.

.evious soil related studies in Ethiopia are discussed and

descri utions of all major soil types occuring in the country, including

repreentative field profile correspïsrding laboratory

analysis, are given

ACKNOWLEDGE

Acknowledgement is hereby made to the many organizations andindividuals whose assistance and advice during the preparation of thisreport were instrumental in its compilation,

The contributors upon w o e work tiis document is based, arepleased to acknowledge the enco ragement and assistance diven themthroughout the course of this work by both Ethiopian and FAO colleguesin the Land Use Planning and Regulatory Department (LUPR

Special appreciation is due to Ato ße:hH Debele, Head of theLUPRO, to Ato Mekblb Mammo, former Head of the Department, to Mr. S.K.Choi, Officer-in-Charge of the FAO/UNDP Ass'isticc to Land Use PlanningProject ETH/78/003, and to Mr. LP.L rt1r Thief TennicalAdvisor of t.e Project, .!ment and a2. st,_

without uilic»: this d(Jc:u.: Ls could not havebeen completed,

In addition, partular t is directed to tneoethe Ethiopin contributions in the

pre»ration of the many 'fiated with this reporthave been invaluable.

TABLE OF C NTENT

ABSTRACT III

ACKNOWLEDGEMENTS

T. INTRODUCTION 1-1

1.1, GENERAL 1-1

1.2. METHODS ANO RESULTS 1-1

2. PHYSICAL ENV', ,H-INTS 2-1

2.1. CLTMATE 2-7

2,1.1. Circulati and PrecipIation 2-1

2.1.2. Tempe-nature 2-4

2.1.3. ' 2-8

2.2, GEOLOGY AND :HU_OGY -1,-10

2.2,1. GeoloiQica -cf nq 2-10

2.2.2. u-eoiwl. . aid Structure 2-11

2.2.3, Drainage 2-15

2,3. LAND USE

2,4. SOILS 2-22

2.4.1. Western Ethio Ia 2-22

2.4.2. Central Etn-: 2-22

2.4.3. The Mortheau n Ese et 2-23

2.4.4. The , 2-21

2.4,5. The Noi..-.shn

2,4,6. Southern Bale and Harerge (the Ogaden) 2-2-:,

2.4.7. Central Hareme P,nd Bale 24;

2.4.8. su: ,-n ,2.4.9. The southern 'is:ift Vetiley 2-27

2.4.10. Northern Ha- .,nd easternWelo

2,4.11. Northeast eastonn 2-29the Eritn oc,astEritrea

2.4.12. Areas of different soil types in Ethiopia2-29

2.5. PREVIOV STUDIES 2-31

VI

DEVELOPMENT OF THE .c,,u RAOLOGY AND SOILS MAP 3-1

3:L GENERAL 3-1

3.2, METHODS 3-1

3.2.1. Background 3-1

3.2.2. Develont of cc.phìc units 3-5

3.2.3. Imary terpretntion methods -5

3.2.4. Landscw,:i, units 7

3.2.4.1. Landfom genesis -8

3.2.4.2. Characterization of land scape units bysoil association

3-9

3.2.5. The map legend 3-11

3.2.5.1. Significant land facets3.2.5,2 Soilmanagement units (SMU's) 3-14

DETAILED GEOMORPHOLOGY AND ASSOCIATFD SOIL 4-1LANDSCAPE UNITS

4.1. INTRODUCT 4-1

SOILS

5,1. INTRODUCTION 5-1

5.2. HISTOSOLS 5-2

5,2.1, FAO :lassificon 5-2

5.2.2, &n- envir 5-2

5.2.3, t'Indger-, 5-2

5.2.4. OcCtii- 5-3

5.2.5. Pro iptions 5-

5.2,5:1. Eutric Wistosols, Awash river 5-35.3. LITHOSOLS 5-4

5.3.1. FAO classification 5-4

5.3.2. Genell envi rcc. 5-4

5.3,3. Char:i,cteristics5.3.4. Land use and natural vegetation 5-5

5.3.5. M

5.3.6. Profile des,ipitions 5-55.3.6.1. 1.ithosol,5.3,6.2. Lithosol, Ads 5-7

5.3,6.3. Lithosol, Mekele 5-90,4. VERTISOLS 5- 12

F 5-125,4.2, anv 5-12

, racterissiu: 5-13

VII

544. La;a and natur,di tion 5-13

5.4.5. ivr.d 5-13

5.4.6. CaJu 5-14

5.4.7.5-14

C

5.4.7.3. Pallid Vertisol, Akaki5.4.7.4, Chromia5.4.7.5, 11ray

FAO

5.4.7.6. Cr,rE..-Jfla Vertisol (manic), Jijji(salina

5.4.7.8. Pellic Vertizdi5.5. FULUVISOS

5.5.7."10.Euric FL:d.isol rida Fluvisol),vet-,

6.6. Sc)LONCHAKS

classiticE.'.?on

5.6,1. idticsLana d and natural

5.6.5. Mdnagmeri..

5-41

5-41

5.5.7. Prof. 5-42Eutri,c 51 5-42

5.5.7.2, E.itric -,ugray 5-46

5.5.7.3. Eutric 5-49

Futric fh 5-53

5.6,7.5 Eutrio Fluvisol (ye: uai5.5.7.5. Elutr:'..c Fluvisol (Sodla (Laaai.. Oma river5,5.7.1. Calcaría FluviscI (salir: ase pJwd,r

5.5.7.8. Calaaric and non-saline 6-68pha,,,e), lower.SaLa

Calcaría F'uvlsC(s,line and sodicphase), h

5-17

5-12

phase), Humara 5-99

q-25

5-36

5-32

5-39

5-39

srti3O1,1 6-40

5.9.

5.6.6,5.6,7,

Mel

OrthftMelka

Mcllim R2dosol s Metahara 5-116

5-83

5-83

5-83

lc phase), 5-85

5-106

5107

5-119

1,7)1z:3-5.A

5-121

5-121

5-121

5-122

5-12

GLEYSOLS

1 FAO ola,,sificationk1'..ie-rYi environment.

-:StiCS5,7.4, id r1-;

6,7.6, -mice

clescri-p1o10,

Gley.

try-cric 010

Calcarlo s

ANDOSOLS 5 -1o4

FAO ciass10Fl 5-104

58.2. 5-105a 6-106

q A 5-105tion

')-87

_hase), 5-8'0-rThic Ke1afo

Solonchs (pee(i3de

5,6.7,4,

ct, 5-107

5.10.

5.9.7.

5.9.7.1.

5.9.7.2.

REGOOLS

5.10.1,

5.10.2.

5.10.3.

5.10.4.

5.10.5.

5.10.6,

5.10.7.

IX;

Profile descriptions

Cambio Arenosol.

A netern

FAO classification

General environiaient

Chacteris,s,,ics

natural vegetation

tcwoence

Profile descriptions

5-122

5-122

r,-126

5-129

5-129

5-129

5-30

5-131

5-131

5-132

r-1i32

5.10.7,1,, Eti. 5-132Metah&f..,

Ca1carir Degen

5.10.7.3. Cecaric (lithic,Crit- D Si

5.11. RENDZINAS 5-140

5.11.1. FAO assific 5-140

5.11.2. Gene. 1 envir 5-140

, -aistics 5-140

5.11,4. vepotation 5-141

5.11.5. flanc 5-141

5.11,5.;ons 5-141

5.11.6.1. Renona,Harer 5-141

5.11.5,2. Rendzina, Mekele 5-144

5.12. SOLONE17 5-147

r,.12.1. FAO classif1c1 5-147

5.12.2. General 3, LI./1 4

5.12,3. r17E..rac-!....E- 5-147

5.12.4. 3 vefion5-1485.12.5. mangemnt . 5-148

p5.12.5. 00:orence

5.12.7. descri.7fions

MO:C

Mt1111c So

rkena

C:)». 1J

5.13.1, FAO c1aseification

5.13.2. General environment

5 1 S

a. .4.

3

5.13,5. uacenee5,13.7. Profile5.13..Y.I. Calc.17 72FL,

1.1, FA.0 classcation5.14.2. General envirnnment

r. 1,7

r lA -Y

1 CZ:P

, 7 4 ria C a ri c

5.14.7

, -

tetion

55,7".5.15.3,1, c (1s.

8.

OT

f,7* and '

5.15.7,2

5.16. YFROMOSOtS

b.

5. 2

in the Rift vR11

:56 natuFal j

Ch.ee

FIJO c as:elmcat5n

5.16.3. Characteristics 5-192

5.16.4. Lan::: ns..,e an.;. - .'al , tion 5-192

5,16.5. ,,- 5-193

5.16.6. 0cc.ance 5-19:1

5.16.7. Profile descriptions 5-193

5.16.7.1. Gypsi c yeromoscci 5.a. 1 '.; ne 'Oh a .!.:E ) ,

Wa.bi Shebele

I owe r 5-193

5.17. NITOSOLS 5-.195

5.17.1. i-A0 clQsification 5-193

5.17.2. General environment 5-195

5.17.3. Characteristics 5-196

5.17.4. Land use and natural vegetation 5-196

5.17.5. Management 5-i96

5.17.5. Ocrur,anre 5-197

5.17.7. ProfileEsc, ....ns 5-197

5.17.7.1. Hu!v,i c Nitoso 5-197

5.17.7.2. Futric f:htoso,. Sanar 5-198

5,18 ACRISOLS 5-203

5,18.1. FAO classificanon 5-203

5.18.2. Genera i Env 1-0 mien 5-203

5.18.3,

5,18.4.

Characteristics

Land u,-.a and natural vedefahon

5-203

5-204

Manactemen'E 5-204

5.18 Occurence

5.18.7. Profile description 5-204

5.18.7 J. Humi c Acrisol, Ann o

5.19, LOVISOLS

515.19.2.

5.19,3.

FAO classification

Genera,

Chara.cteristics

5-208

5-202,

5-209

Land use and natural vegetation 5-210

5.19,5. Management. 5-210

5.19.6. Occurence 5-210

Proflie uerriptions 5-211

5.19.7.1. Uiromic Levi sol Humera 5-211

5.19.7.2. crAc L; visol (s' 0.1ase 5-214

5.19.7.3. ti tic

5.19.7.4. Luvisci s. Orbi le

5.19.7.5. Glevih Luvi sel Sectaria J-A.Lo

Orthic Luv'',sols (st 6-224

5.19.7.7.

XII

Orthic., Luvisol (sonty Dna e ) LHrna 5-226

5.20 CAMBISOLS a

5.20,1. FAO classificon -228

5.20,2. General en vnt

5.20.3. CharactPritics 5-230

5.20.4. Land ose and n.t 5-231

5.20.5. 5-231

5.20.6. Occul----,ce 5-231

5.20.7. Profile descriptions 5-232

5.20.7.1. Gleyic Cambiso1,0abus 5--232

3.20.7.2,

5.20.7,3.

Eutric ramb-kol, Tio y

Vertic

5-232

5.20,7.4. Gleyic Car¡H:sol(c,- -),Borkena 5-242

VertIc :,?,orkena 5-244

-FERENCE

rEFFW:ACE, 6-2

Rainfall Pattern '::edt.idns of Fthiopi -6

Area Precent of Different .Spil Types 2-30in EthiopiaExtract of the Geomorphology & Soils Map Leg. 3-12fliassas of Chacteristics used td ;-)escribe 3-16Lndsoe.pe urr,us in the Geornorphr ancSolis Ma:G Legend

ST DF

.IST OF FIGURES

.1-gure 1: Location Map 1-2

Figure 2: Mean Annual Rainfall 2-3

Figure 3: Rainfall Pattern Regions 2-5

Fi cure 4: Dereraiised Thermal and Al ti dude Zones 2-7

Flqure 4: ' ,.idi'ature Index 9-9

tc!ut 6: Generalized Gelc,'7'. Dep 2-12-,oddified after 197'

Figure /: r- 2-16r 1977)

Fidur 8: Land Use and Land Cover 2-20

,gui 9: Do8,....Lidn d, PxiStind Soil 2-32

Figure 10.: Main and Feo 3-2ih the andSoils Mar:,

r:igure 11: Landsat index map 04° Fthiopia 3-4

Table 1.Table 2.

Table q,Table 4.

XIV

CRO3,S-5EC1I0N8

Ab 4-2

Ac 4-3

Ad 11

Af 4-5

4f4 4-6

Ak 4-7

Al 4-8

Am

A1'1 4-10

Ap 4-11- 4

As 4-12Av 4-13Aw 4-14Ay fi -1 5

Da 4-16

Ec 4-17

El 8

Ep

Ra 4-20Rb 4_21

Rc 4-22

Rd 4-23

4-24Rf 4-25Rg 4-26

Rh 4-27Pi 4-28(7- 4 4-29Rk 4-30RI 4-31

Rni 4-32Rn 4-33Ro 4-34

4-35

4-3671_

4.37

XV

SECT IONS

Rq 4-33

Rr 4-39

Rs 4-40

Rt 4-41

Ru 4-4?

Rw 4-43

Rx 4-44

Ry 4-45

4-46

Sh 4-47

Sk 4-48

51 4-49

Sm 4-50

Sp A-51

Sq 4-52

St

Ss 4-53

4-54

Su 4-55

Sx

4-57

va

va

h

4-58

Vc 4-61

4-6'2

4-63

4-64

5h 4-65

4-66

V1-7f

vr, 4-68

Vo 4-69p 4-70

ici 4-71

4-72

yr 4-7'3

Plate No.

Am3, Ac4,

2 4 2, L L, = , Vy

C i V

,V

R t .

Rs

XVII

r? Q1

,Sne-

PtV

C

4-85

,4 -

Rf ,Sx Q

Ab vi 4-89

A 4

o.3- 5(.1

4-91

10 5 ,L? 5 4_92

Roa

2aolrn 4-93

=-:

12 As A .-, :0-V,J , Av .4-942 9

13 V C L V f" , V r ,

1

V U 4-95

14

ib

, ?

v ...,AS

,

5

Vh,

.

V1 ' ,

Rr, ,v

V y

,

.I,' ti

4-96

4-97

20 4-102

A b

2O

Am4, El , 84

4 Ad`'', Af", Am 4-86

4-104

108

4-111

4-1 I 2

4-1 13

4-114

115

4-116

4-118

4-119

3 A Li

24

25

rn

EP,

Ac .

VI

,

Vc9

va

3Rh

9

,

27

A

vS1

Vk

, n

vs 5 1, 2

Rin

g

2

- G 7

5 Sm

o

29

).7)

C

1 vh1, v cls:

2's,

9

V x

32I

'4

g v

r

n

36

:38

Late No.

71o

4-103

4-105

4-106

4-109

4-110

P1 ate No

39

40

41

X IX

PLATES

4-121

122

4-123

CHAPTER 1

INTRO° CTION

1.1 GENERAL

This document is one of a series produced during the course ofthe

FrO/UNDP/ETH/78/003 project, Assistance to Land Use Planning, in theLand Use Planning and Regulatory Department (LUPRD) of the Ministny of

Agriculture (M0A), Ethiopia. One of the main objectives of the projecthas been the development of a master land use plan (MLUP) foragriculture in the country, based on the FAO agroecological zones

methodology for land suitability assessment (1978) developed forcontinental Africa.

A fundamental requirementf the planning exercise has been thecompilation of a comprehensive land resources inventory of physical land

resources of the country. Without tris comprehensive land resourcesdata base, land suitability evaluation ad development strategies

could not have been considered in terms of geographical realities.A location map of Ethiopia is.shown in Figure 1 for reference.

1.2 METHODS AND RESULTS

The report summarizes the methods employed and the results

obtained in generating a 1:1 000 000 scale Geomorphology and Soilsmap of Ethiopia primarily in support of the requirement for a land

resources data base referred to above.

Geomorphology and Soils data included in the map and legend and

in this report are derived from a geomorphic interpretatiOn of 71

scenes of Landsat imagery, available surveys, field traverses,

topographic maps, land use data and agroclimatic information.

Landscape units approximatinq small groups of land systems

(Christian and Stewart, 1953), and individual land systems in some

cases, were identified in this way. Each landscape unit identified

contains a unique soil association.

,

.17,4'ERYeo. Mat,

,)4" L-4/e,

a a

".?

1 , ,,:'p...7,-,/

e di E;;I::': ,,,,, '=.:21'44

,,,,t° "-'-,,...=:, .,,,j'.1.

, 4,..V. e eAlez,,,,

' < " ''-, R . '-', ,..., ,4 ,. .el '''', '

's\ '\*,..

e ''.', '' \*aq' '0,12.C.,:s LE

.4..,,

,' --, orzt-,"" tt:-

4

%

...,,,,., -= .

- ,'. I1

7..,..r..., .,....,,,,...----',,,

,,---C''''ri °PEI rel,),"0

, -.4,*';.-.. ; i!',',C1,-'i ,--' ' f

::,... 4 ,.- 41 , ,...,,i .-% r. , ,,4 . ,,,

..Ze a 'aa, ,et., 'ar,a'-....., ) a,

4,,,,,,a4a.a,:,,. "S. d tt. - - ,.4, _,...

Figure i OCAT

,..,t, 4 = =.

, ."D A p !,' kw_ '

,, / '). .,;:" (-1,

'44,

1---"-' *., ` ',"

i , : N.., ,,-- , --,:

V'' ''',..`,..7., ;" ,( Ai t2-74 F? , I \ ,.71

-a.(,,,,,,L t .

tZt

;

30RENAI

uscat.

,4'

ke.s7

0.4* +110..

i'0(5ADEN)

s.,

JILL- It ,

e'r

The Geomorpho'ogy and Soils map compiled in the manner described

is comprised of eight 1:1 000 000 scale map sheets and has an extended

matrix legend. Since the map and legend were intended to stand as

the most complete, independent data source on the geomorphology and soils

of Ethiopia at the time of their completion, in addition to providing

the neccessary thematic data on geomorphology and soils for the MLUP

exercise, both are considerably detailed. In its present form the

map represents an update, for the section covering Ethiopia, of the

only other comprehensive soil map of country, the 1:5 000 000 scale

FAO/UNESCO Soils Map of the World (1977).

To provide a comprehensive understanding of the nature and

distribution of the various map units identified and the methods

used to delineate them, the remainder of this report is structured

in such a way as to give a progressively more detailed picture of the

different components of each. Chapter 2 for example includes a general

summary of physical environment of the country with background on

climate, geology, geomorphology, land use and soils. Details of the

methods used to compile the map and legend are contained in Chapter

3, with particular reference to the influence of remote sensing and

image analysis in the derivation of the final map. Chapter 4 provides

details characterization of the geomorphology of the various mapunits identified. Cross-sections of each of the geomorphic units

identified and the 382 resultant landscape units, together with a

summary of the soil associations which characterize the geomorphic

delineations as particular landscape units, are included in this

chapter. In addition, plates are provided in the second half ofChapter 4 to illustrate the nature of the image signatures of many

of the geomorphic subdivisions used in the construction of the legend.

Chapter 5 makes up the bulk of the report with details of soilsoccuring in Ethiopia, supported by considerable field and laboratorydata gleaned from numerous existing soils related reports and from

field and laboratory investi ations carried out by the Assistance to

Land Use Planning Project.

A brief description of climat , geology, gemorphology, landuse and soils follows_

The intent of including information on climate, geol gy and landuse in this chapter is to provide a physical and geographic setting forthe oeomorphic and soil patterns that are briefly set out here inoverview form. Thus the information on climate, land usp and geolocyis in no sense complete, while the expositions on geomorphology andsoils are very general out will be elaborated upon in subsequentchapters.

At the Pnd of this charter. a list of previous studies with ageomorphology and/or soils emphas-is, or with geomorphology and or soi-laa5 a significant component, is given.

2.1 CLIMATE

Ethiopia is distinctive in Africa with regard to climate forits large extent.of high altitudes and cool tropics. Howevergreat

variations in climate occur across Ethiopia, and are to a large teJ:responsible for the country's widely varying soils, and to a lesserextent, widely varying landfoms. From thP deserts of the Danakilthe mountains of southwestern Ethiopia where precipitation reachesover 2 500 mm annually, climate is quite faithfufly reflected in cIrds,patterns of soil development,

2,1.1 Circulation and Precipitation

The main influences on circulation in Ethiopia are the IntPr'-,Tropical Convergence Zone (ITC7), the Northeast Trade Winds and.....theSouthwest Monsoon. Precipitation is in tum strongly influenced 'the relative movement of these circulation sy,-,tems over.the Ethland mass. In January for example, the southern position of the

PHYSICAL ENVIRONWNTS

- 2-

brings most of country under the influence of te NortheastTrade Winds, resiYitinfl in an ext nsive dry seaSon (Hurni and1982)..

Northd wvement of the ITCZ over Ethiopia in the period Marchto june encouages the progressive movement from the southwest of moistu:laden monsoonal air masses. By Julv, most of the country is under theinfluence of this Southwest Monsoon which brings about the onsAt of themain rainy season (krempt) over much of the Ethiopian land mass.

A small rainy season (bel,) results from the movement of a aipressure system over the Arabian Pennisula and from the southwestover the Indian Ocean .( Hurni and qAli, 1982). The beig precedes 1rHmain rainy season in the south and southwestern highlands of Ethiopia.

Apart from the effects of major circulation systems, the phys.graphic ab:rupthess with which the high altitude Ethiopian land massstands above the surrounding lowlands is a major influence onprecipitation throughout the country. Total amounts Of rainfall aresubstantially higher for much of Ethiopia, therefore, than for

bordelow..lying countries,

Rainfall amounts vary wiliply throughout Ethiopia and areprincipa17!,,J 'determined by i) the direction of moisture bearing

seas..aircurrents and il) the elevation (Gamachu, 1977). A c,eneraliseof mean annual rainfall is given in Figure 2.

The highest values of mean annual rainfall occur in the south-western highlands of ilubabor, near Gore. Here mean annual rainfallis 2. 200 mm. In fac,:,all highland areas in the southweSt of overm elevation receivoeten i 400 and 2 200 m6 (GaMach6, 1977). For

much. Of the remaining highland areas meac rainfall lieS betwei 000 and 1 800 mm, higher elevations lenerally receiving more than1 wer elevations.

-

f,tij- . A

2 - 3

OPRAINF4Li

RX o ogismataterii=

,

s

4'3°

e

J.:.1\1(:\;!JAL

.4/

2 4

Rainfall decreases abruptly descending off the highlands down

the escarpments of the Rift margins in eastern Welo and Tigray and in

northern Harerge. Mean annual rainfall in the Danakil Depression and

on the Red sea coast falls below 200 mm. The rainfall gradient is

much more gentle to the south, southeast and west. Mean annual rainfall

in the Ogaden only eventually decreases to less than 200 mm, and in

the western lowlands of Ethiopia values generally remain above i 000 mn

Seasonal distribution of rainfall is an important feature in

Ethiopia. Rainfall pattern regions are shown in Figure 3. Marked wet

and dry seasons occur over most of the country, the exceptions being

i) the extremely dry areas, as on the Red Sea coast, where even during

the "wet" season there is verY little precipitation and ii) the extremel:,f

wet areas, as in the southWestern highlands, ners even during thennd.

season there is significant preciPitation. The tiMe of Year of occn

r wet and dry seasons, as well as their relative length, vary widely,

2:1,2 Temperature

Temperature is greatly inf- by the rapidlY Changing

altitudes in Ethiopia, Lateral vaninns of relatively few kilometers

may result in vertical croes of i 000 meteN'.... Or m.n.ne in sume of the

major canyons, on the slopes Of high along the Rift

Valley escarpments,

The high correlation between altitude and mean daily temperature

during the growing period (R79 for the southeastern lowland -

the Ogaden and R..95 for the rest of Ethiopia) allows a definiti , of

thermal zones based on contours. This .s shown in Figure 4. Mean

annual temperatures tend to ..bB 2-40C .lcsr than those temperatures

indicated in the figure for each given Lone, however the temperature

pattern of Ethiopia is clearlidicated

Extremes in.: tent.nture r ice fromnthn

of 34.5°C in the Danakil depressinn at 180 bel Msl t° M°'2.ain -

over 4 000 m above Ms1 where minThum ..:tures fall bPlow

.7r1,

1 r",1 O. :.'it,a_.. k 41

I .1\

2 -5

F u re

77

,

,'. 4r 4 L.' ....,/ -I, (. 4 == 4, ..: vy,

vv.,,, -"-j.' ...v." 4 z-, 3, , 't i-' r'

94:1/44.2:::,""'1 '4;4 ai,i3' 1 %.,

N.

LEGENrjRdires euertereer

frffRr???-e.. ?rani larte-feata ouArrnef

Roirea tf- ufan-fs.f, u-Arnetr anc?craliv.tv.3 t4.,¡402=ti=vcer

Raz4474.1 ti. eszel"eftrAn wifeter ono,.rrsArelinq lossaIN2r.Strefffil raint Zre aiirrerAgrf?;:rieri roim; ???;3ff--.117,f-ief? ra?re, ??

rndrsirlr: r:,-aure-sfe%ane-.????,: eifffita:

TABLE i RAINFALL PATEd RC1IS ETHIOPIA.

LEGEND TO FIURE 3

de Summary Desc lotion

A - One comparatively short rainy season in summer

- One comparatively long rainy season; dry s'eason in winty_Some stations with year round growing period

One comparauively long rainy season with rainfall peaksspring ano autumn separated by a season with less butconsiderable rainfall

- Long rainy season in winter and small rainfall peak insummer

Main rains in summer preceded by a small rainfall peakspring or by a prolonc;ed period of.moderate rainfall

- Two short rainy. seasons. Main rai-S in spring, smallin autumn.

NB: Spring, summer, autumn and winter refer to seasons of the yearaccording to common usage in the temperate northern hemisphere

0Ac-c<

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trri1I

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.3 Evaporation

The potential evapotranspirati3ncountry. The highest values arefor Cone, msi 320 m: 1886 mm), and.(yea v PET for Goba, msl. 2700 m : 901

relatively dry Riftsouthern lowlands,seasons however P is

PET are about eq-al.the wet seasons

2-R

zero overn, un the 1,10p: reaches

falls are recorded in mos.,. Betwee

areas of hiohland Plateaux and marginal -

temperatures are between 10 and 20°C%

varies widely over thethe lowlar& eve--Iv PFT

wast values at altitudes

. Ras Dejen, light snowextremes are vast

re mean annual

More important than the-yea f PET's are the ratiosPET/P over the year (:19..5 ), In highlardf,. with theirhigh precipitation (P), yearly PFT axceed P )nly durinea short period in the year P Al so at hilh altithin arei,,is with a rather pro,_.yc riny arson PET exceeds P only

during a short period in the urseason, rhe opposite Is ,h-u. 4,70-

the riry areas in north, east and t Ethiopia. PU qeds Pduring the year e) ring the rainy Ihaason, In the

in the rsu,rn - s and in LhePET exceeds hy P, II,rinq the rainy

higher than PET. In the highlands yearly P andDuring the dry period PET exceeds P, aurinu

ceeds PET,

,,,.....,.., ,_,,...

% ,...., 1 ,

1

..., .

"I--7.72.,-J`' ,

2-

. . - ' . . t , ,

'''' I i, ' - ' I., A l'Il---i'''',": -.- l'.. ' ' , -; - .Ir. : - ' - '. - '' '' -

, _. .

-

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0

<02525 Dr

0 5 1.0 intermed,cite

-0 Humid

- "

_

E.GEND

rcOncL BounciorycmnscaPve Regoon

-

025 05 eret y 'Dry

, -

- 1

e ;

I

P

. " - PE 17 Poenì Eva pOtionsPt ration_ - -

. .,

2.2

2.2.1

,ertie-(:

Peleo

-

Coo_ a cae,

foms of tho niajor sih-crust referd to (u; t Hurn of Africa. The

The folleof Afric

by recent

is;lick f..

S

Quaternary: local loe: areas

lachstarh.

and iilarihc rya

earlier alkaline and silicicoltic fissure errt

s;ats (f series in central Ethiopia,:

rontine .:sitich ofeastern Ra:

shccession of strata in the

unit ofearth'sthe Arabian

- and htfui exc.

.:Pnsive

glacialrPef

and p; rociaste

finally weepe. out betepn two sandstone herizons

facies,

ponninsula,the and the Gulf of Aden, Djibohti, Sollaisia and thenorthPrn part of The histnry of the h of Africais closely related isc that est of the co firPnt but doesdiffer significantly ts.

f tO tb.. andGurassic-C. limestone,

Precambrian: rnuious rr.ias and5 of schist and gneiss, as

71 - Tt sedimntary rocks and

int:u u rocks underlying the whole

of Ethiopic rorm:u an intensely folded and

foliated me , lic base:c, nr; schistosity and axes

foldn --afly trending north-south or northeast-

SOUth:sd, tentatively divided b2 an .Drmity into

ukd a wriger

The rto

bifurcates in

tran. n, nort

original lar

thus been d'A

OfE:.)rposed

, in total

The f Africa

- efi- tre

Eocene

thr

Mlocere to the "srnary,

.nt-sor

2-11

, this comps is generally

the riasemient Complex,

of Africa

boments

ast re ::ectively after the ro int of vuhation.

upliftzd swell

into two extensiv !nits by the Rift

rreneir-

s of

, by tk,

SrIcan 51v.

mes s. resditing from the enorme us

htem - the Ethiopian Platean to thn uest and' ohe Somalian. Platean

Mesozoic havP been out -k'n western

Ethiopia, lei-tiler basals - rsc overlie u:-f:ent or

c.,cernatvely ttHo:'ystallide --t itself lb dXposed, except

overlain uj alluvium.

Figure 6 is a ical

2.2_2 Structure

4.

"....J"

40"

'

- t

" °`'," r",r14':

Flqur 6 GENERALIZED IOLL A P

( rind ifiod t er " m "ft, , 1 9 7

2-1?

r"tR

G EOLo.IY1E GFN

PP TEArrit\R"tx14.(1'

" " ,e1-...:,1 t - '

-:.'1\...,..;I Os, r-'-.}.., 1` + -;', ('`.., \

- , t",t) ,-A\i' -o -,' P. / t,, VX

1 .I.',t./..1,"-74, ' '81/ ' '''''''i. ,' '& ' : , i ' " : ,7. ,_,k, , '',-,..7.3',:. +, ., r';'''.." - - /. ,/ I,

'v,., ;,/,.,^,,,, /,..-: , 5.-- ....,./ ' -

-,...,- ',,,r .v,,,, r / ,... , -.* - ,,,,,I,.,t..,,..,,y V kiriv.,,.,,,Z, z, --- ---- _ '.... , *, ,.. ...

, -&-+,,,VVIt'i 1 ,0`.."/", . -,, t ,, ,;--t-- , - ' -°"," ,

. 1 AC.."--IF, 5^...)--:" 1 ', I V .,.' , / ' ..t......L...._ ..._ ;vvvv,x,,,,,fr, ,, v:'.. .-, ,,- - ,

' N'47Cl':''::"':y.k.- -,.1 i Ni 'kt ;,,",;,....,g V

=1 , , /-= ;,,W1/1r1 /1.-k1V11111. 1r. I f,r1,1,!°` ,P V' ,..,r,,- t N i N ,4," -,VV,,,t/s414.,'VV,','y s t, ,.,q p,,,,,, I, vy ,,t "-- , /:, N , ,,,,, k \

r4.,,,,,,/,/,VVIt= ; 1 = 1 . t .. = \ 1. 4,1 ,, I ,, , r 4

;11,0!V"e. NJ` .' ' -,i,.-'44, 'V , \f,,,,, , , I i ' ..k., v V V %IV 4,V*, Y''',,.. 4

L. ,,° V t !$;,,,L1f V , ,,,,',2 ' , ,,,,, , : ," ' ,, ,';' ' s ,-,;1',,,ir,.,,t, , ,\ -!f 114/1rtVli V°,1" V 0. "1 té° ;,1° i 'r",'1.1,[1°,,111.1°."`-''' ,,N .1°1'4) ' t, ° '' -f - " ----.--\ 1 ,11'14-41°,1rV° sit'11,',A1 Q'1.111k, VV.°°° fVVV,°- , s.-i '",,' -t- '` ' `'-"...

,'"1....

v't,'Vkl,r,,,,,,', ,,,,,,vs . , ,s ,":, ..P.niv il.',',, ,,,s ,4' -,,,W. +,r'''*;` ,'Z'" ',.', '''',',1: ,'',..' ( -'-' --t,»..., ' ,v^4.1 ..." 4,-, V ,` VV1°'°V V `.,.¡-°/ .'" ..."7. '....1.--, e',.....r,, ,7e - s, ,,,1,.. '.. ';.

-A.

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k ,t=

rate. '

'vv.11,

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All0N.00,, 410,04004,0a,,Coic0,00,.. 41000,4,,

or= A.. a 1,...t,,,kkrttkt1,1.

, °

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v.; te,'".4 r,

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rrr7/

'X't, /X" t t..711 ,t-aatt, =t.trr,ltrok=te.,Nttrkstor-tr, :///,62,/

CO" =Orr= tt.,=rt...XXXP/1/

.-, t1= ttX et, doit/n/r/.^.4144

'47,0z,440

,0 I. h 1-==== érted. ;

Co,',- 140,... -' - ' '''' ' , i 77--Z Z.,- 01 c 4-'0- 5't0,004 ',;-,", 0-.1'1,0,

I C,1004,4, ,-,440 :100,1^ -.s-r,o,-4,S,e-r",,.,-. -.,. ' - s

, - ,--7., c,,,,,,,,, s ,,rek...kr 1 = rs,.....$ rc ..,,,...-,,govt-.:,.....e-tj ,-,, - ¿w- tVh -s., .., n Gn,cme,oan ..

...:, ...,,,,,,at:-:,r.ntior,,,d Y.: 4, - ,,,,,a.'

..., ,.... -.. -, ,,,,,,,,»,v,, ..vv,,, ,

V J . v Iv v .,,,I,''' 3, ,,--

. 17) ..,:-.,": v v v v.,v*,v . i ' 1., . .' V ' 1

;%'-jV1, i /v6'n4'

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YYvvyv \c,...',,sy,.,:. '-' f °° e '- -

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,

L...7:----_-_,-;17-

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,,,,,,,,,;,_ -7., ,...

r.V V tt,,J '.''' '''''..;'ff:::::i.,, '?,. '-'-:: :-----4- ----_,_ 1--- _IL- _41 :- '. ,..

, ;_:. .:--,

r ...,,,.... , 46-

1

.

v°V°P0 t Vs " '°°°'.`'...Y.,"'''.,'''/-

"4i , -

._,,,, :.' 2° st. 6, ...

-' r -,- :1,,'"'Ne :',111

."iv),' ' t , tj,-: :.,

"':- --.4 - -:....

, -- - k.--,,,, ,t,v

inty.;'.. ' .1*. * * * 4." :2-*- ' ' r -'::444.`:,,,,,,

.. - '"'L--"'"'?7,--''''''---,", -

">'t ' ' "

.,..'''

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--. ......s,

-v

,--...---s----t

:

otrolVrtr, l'iCretrt ett,

el da rack re d04'1,5,5 to we,fit ttgnIcr,b41f0

to the east,

Much of the Ethiopian plateau lies above 2 000 m altitude andcomprises extensive areas of structurally horizontal table-land, Thisis an expression of the essentially flat lying nature of the peneplainedPrecambrian basement rocks underlying the Mesozoic marine sedimentsand the Tertiari flood basalts which followed the great swell (Mohr,197U.

Despite the dominance of tectonics on the large scale physiograuhof Ethiopia, on a smaller scale denudatioral, depositional, and volcanicprocesses have been significin shapit the surface of the country.Erysion fer e stepped tectonic scarps

th c_r, the Ethiopian plateau,aI thcrh the western ebo the Rift still remains somewhatdraatic in relief, more so than the Sudan border scarps to the west.Since the gre swell, enormous has been available to streamsdescehdi h, vie plateau to level over relatively s',.H21-..:. distances,Conseateau it 6,:. y incfsee , gorges

such as these of -ibay fB1uo Aile) and ,ehail 1V TOntS fromthe plateau, to ri..,,,ers he ow, of i 000 m or more over relatvely fewkilometers horizontally in such situations,

to these massive erosional scars, extensive Tertiaryvolcanic piles, including Mt. Ras Dejen (4 543 m) occur on the otherwiseflat platP,au.

According to Klh'r (1971), "The '--omalian Plate, u lies to thPsoutheast of the Rift This part of the original swell shows0 much more appreciable tilt, towards the southeast, than does the

Ethiopian Plateau, and th.J: dip of the strata is closely reflected inthe physiography of the 3OTISIiar Plateau... The plateau has no clearlydefined margin to th Q-utea,t, but se radually down in thisdirection through and beneath the Indian Ocean,"

Hioh summits occur al oro structurally controlled ridnes of theeastern Rift horst and atop Tertiary volcanic piles such asi Dato

(4 307 m) in Bale.

2-13

morphology of struotoral

2-14-

The Rift VC1 is an Auttered withevidence of rerent vo,tAH irr nesivestepped horsts of the , ateanx on s--;Rhsvst maiginsIt widens significantly at the , Last African Rift,the Red Sea and the Gulf of Aden tectonic ,on,c-nts beyond Av'ash

in Shew, an area refered toas! -tne .RfS Tr urlo. Ltie ette(,tsof extensive fault swarms are visth rougho:.f.,the kift in the

lineat'- are mostly a 1

in sympathy... witt the main tectonic ,ons ueritioneo aLr,

The rn and central ,-,1 one of - he Rift contain

of lake ur :lrft.- .,:-.1-z.ed by .Of. alkiàlit: -,:y ,:. In thri.:E.

Rift fi on rof. :ns as h flOt !aake 7ibut .. s:-:fftds to be -s. 1.evel iil Depression fin-. ..:orth

and to around 400 m at Lake Turkana the south,

role le is a very r i i Iicant factor in

ths

in une otherwiac undulatl

the Sorana,

sediments, Lan!:

or plains in n,

to rolling

ontr,;--

rhaceduf,

penches inmajor ri ve corcar, Plateaux and benches terminate n teep, ai.tectedescarpments where resistant strata have been broken- k,

of landfor intrusions into

. schists o- tend to be more

resistant to erosion than the host, rorks, tor ing out as inselbergs

of areas mph as

The essentially flat lyino -lop' basalts havepreserved the relatively flat uJnmak,o, Volcanicrones and domes forre hito - the

2,2,3.

?rIP

Seure ofr1,,

moo

rivers afand east

Examol

'ain ln the

Et;d.

ique 1LhÌaOj.

te

of an extensive c-k of' rivero

Ethiopia are

in Dart -fa.. the

Valley,

and margichns

a pi alon

,

aira

2-15

Leo 1 Lne Kitt eakiev

naveed vast plains withitionallOTtlS include.

and the te Sudan

:hiepi and its!nis 1,,,d to the

in the country.

The Ethiopian MaAcaan in the previous Fectioh tne

rtver,

4L intriCatiL,

- 4.4 -4 1,4 47-E, `44,A 4444 '44 -144, - 4-44 .4.4_4,4,4444.4 .) t."¢-4.4-1" -44444

==:=T=

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dt.f.1 ChtloAt. Niio -An '

SSS:,:.-r

iNDVAnfl OCEAN5.4_)

l'otios (c^i,o.0;j)

I C ilAW;nQ .0 (c(f4: K)

t IF L CLC;i:16.-0E

2-16

CA% 444rvls14 4, n4144417,

d 0r;,.. t<71:11;',..-ZQ':

1-t OWL

-'4444 1444;4400 n=tt,=:=

;

1P, innonnye,p,Ang.

' l s°,,,

( 4' ...!-4'..'6:' \ .....---- ,

d1 ,v '.:,-, ,,,,:-.., ' , -6- f y ,4-, 444.4 '

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4

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F: MAIN RIVER BASINS (modi fied after Gamachu, 97 7 )

'

10°

2-17

River drainage on the Somalian Plateau is tcEabid influencedby the southeatarly surface dip of the -ological strata, with mostrivers fi M this diretion, T. reaches of the WabiShebele th .in rlver sv. on the Soian Plateau, rises in. theChercher hicnnds on th a,.:1:t side of th.er eastern. Rift horst and inthe Chilalo.mountains of Ars'L The Wabi ShebeIe has developed a dist-inctive ,-Arde in its t:,"_!er 'J. bus this diminishes markedly asthe flows out iW,:o the 0" 3-LH: , it aso fails to reach t.,esea., terillinating in a closed basin i. lie. ) main rivers ofthe Somalian Plateau include the Fafen, Dawa, all of whichterminate in closed basins in or near Soml:a.

of those main rivers

,pcnal cont..ol on ths-ieaing geo thPe. Mn. most app;

:ted by uit over long sectionstheir channels are the omo, the Didessa ant,. the Fa-Fen_

LAND USE

Three main factors ' to have ia; both the use of the

i 1.-' and the nab:::,n cover ty. they are presently,ressed in Ethic, a,

The influence of climate is marested by the responso in landsure parameter their

croi cki ation is the priq available.

:Aural li,estock raising becomes predef' is also mani-fPted in several ways;

wormer reas,

end that , in thaEtdic 'a ranges fle. sert type in the Danakil

in the affectin the concomitantctivities,

using actia ties to itsvariousin most of the arEa,to arid condftion,

cne!

ofofin thP c,The climateto the crnivariati-

Sihpe and ttoninesswhicn land use activitiesqerualiy still tn5plate5

When

praotiur a. ilso inflnehand cultivation on steeo,y slopind rand.

its cuItu?elthe cover typewith high populatidhcover ontsigL

to th

ascern

e-perienced coîura rab

auras ef natural

:2-18

.rain to,as elopes are

Ale the rolliho

eS Culturalenample terracing end/or

its distoi5utiondract- ras.-ienhco

55j;1,;

esaere OT Vege:

soil C

are:; of th:e eed:country have

:,ah amasar; a; and d',ierefore .ave 1 arge

intact,

left

.r1QU' 8 i8

any ee. vaga

for cropp niL3.

of liV'eStotsLcover is ...

the railiy seasoiextensiYetane,asof the... fo.17

when poplsic .

Aoc lci% of Ethic intensively cultivated land. Hardly,n is virtuaTly all the land being opened up

grains, leds a c51, :7-,eed.z, and/or grazing,

0,,:neraitzedlev selland cover mar. Ethio 4

nd ten6s over-steced.and vegetativefe w .cehtimet'..., 1 at the peak ,

Crop. .esiduce e e also ..thus there areoi. bare soil ..'end of the dry sedsoh .A the onset

J, so of courseve has v.hv: d this cc c cc. up onto steeperrws has praCt. years

'h ay ano y deqracevt.Terraing in suen....areas,repair.

may....beabevound

susara undnre

natural vegetation outkore homewhat ruduces.pressure on te lE -uosshfle less sever. ongOing. With

ut:uulatîon a IV cultivaterl , _ wnich aree lands, ¿u-

' w:ore ed,

hSignifirca- hreas. in nortb-..,

kefa Gaw babor andperennia: ctiltivotionareas arc istiars:a. I.6% ofthe cv ntry. Cos'-' -0PPing

of perend oomb,eetrernely intensive asso:cc i land use,as for exwul s in the areas of ensefe cultivation where ,as.'ng landsara dea due: to veu livestock densities, or for

reas chat and cofee cultivation in te. Chercheris intensively cniti r..-ed on

ly cul Eth' pia.uah the -ilarmin ncc 01

55t

2-20

i.ti^ta 4F-1

Fig. 8 GENERALEED LAND USE AND LANi.)

A;.:4-3-41bi:4c ccsvb (44,iro-oirbe

igh Forest

dknd

1 rid

rT1)-4,

't

"

... . . 5-5r. ', : ' 5 %`-t 7 \

-''''''' ' ; t . i : e-'=----L 5;i 4. ..:,-;--, -:,i,1;4, ,,44 :..::17...;-,,,,,i_7(

. .4 ,I 4-1.4,,=....r.e........:

i,/"..1--...-.. --,-., \-d.---,

'." 1

-

.1.

' 41.,

7""

--,. Zi.';'23,,

--* .

Scale iOOOOOOO

SworrO,rrlarsh,iporion voodlood 84

beehiond.

Etpced rock or Sordrfdco.

Hitli ere;/CuNi'4nted Load

Bushland or Shrub -iond.

Oper3ushei,Shrubb3dor Wooded Groo.slor.ci.

'4,' Solt fiats

body

CultivotediBushlo,,.;

od/Cultivoted

, ^ ^^-1,

uwurst an :,)

of the mixed

500 mm.

and marsh

productn

livest

-

ga is in the southwest, where rainfall is

-foqeg -Cimately

,% of rthlopia. In the rica r; of the untrv -wit, hioner uecipitation,

such 7v given over to :ant livestu, grauE". with.

sctaate un in - -if tac

,;g% bare land,

?

Appro.- .2% of E pia has 5 state

farms. Gene. the flatt ana, gs not present much

problem, , iii.cularly on the river irrigation has

occasionell nturated v -tic characteri tics and salinit

induced ( 5flting of - ''7 suvfa-

nse coniferous ;rnei mixed hi gs-ts have been removed

over most of their extent in Picola, and cover now ot8v 2.3% of the

country.. 2% is Pet= hig i5lorests ently

remnants con ilie forest are still

- in central

is perennial and s asonal so .

pre nally hot eco.

al - vsnadir or rcrashnt

acti .Cies a5 for ; salt

y

forming factors take o'

In northPrn Kefa

6 and

voicahli:s

As this

plateen

sic. and m,

colluvial slopeS, at. the

ntion previously,

U is not,

ra:rfall of up

In vPry stai I er soila

inant soil

with

perlaits, ChrorOc ano Pellio Vertisols otwh, - do, the cc.- icrease

of the higihland plateau.

after O:,seaht from the hiohls,

river ont to

res 1 CT:T.sel si. e I3

lso occur ery

ripice extr, ,eosoral flooding.

the Berg and its many tributaries,

The soils of no,rthPrn

Bale and 51dam are pnaminantly , .n on S21.ny ha,canics,

parts of

al s

and

;.re also

2.4 SOILS

The. ranges of c. iy,.. parent material

lnd ..n _ havP the rsisuLs. 'soils are extremely

variable and that, 'iffereht parts of IS country,different soil

2,4.? Lt,

In wes: rho__

the flood plain

square kilometers,

Eutric Gleysols ano ih

areas within the flood olai

Eutric Fluvisols occur adcna

develobed 'AP ailhvial a 1 :HuyLI

The

however, scL. jw: riected

to rea ter than ? 2P0

irrPspeatir-

is

2.4.1 .

extreme ston:ness anc;:

the dramaic. topograW4.Andos.ols exist, oart'Os tne

ash the ssi'spl. pare T materials are

2 - 23

alt h Tarise s in sou-sh ere ms. ;'ecehtastic mateniels Limestone, sandstone an, .semenis materials

al i appear locFlIy, most notably in the Blc- nce, Rainfallranges frcm T)!'A to I 603 mm. Soil diffe-,. ..Ls the centralhiqhland plateau are 4 a response to , spiv.

Eutric Nitosols and L, Luvisols, with inclusibns of Chrb;vicCambisols and Lithosols, occur the hillF ano mountains. PellicCouyc. Vertisols occur on thP flatter lrodforms includino a greatnuii¡Lier of both smal) and I suasonal drair d.eficien-cies which e littered The ccs of the

2.4.3 The Northeastern Escarpment_ _ _

exclumcalled -extremitythe Rift '

soils, inbeer in::

on

valleys, sides!Chromic

culti

:after la rms, which incland voicanio plateaws, are gens

vertisol VertiLon mfi

on tne stor iatn

able, refie tinqhave in

diles as 6 resu,_ ofesli oct ssourences of Mollic

, and pc

honst arm of. structural

is reflectedf the

in czZ's

of years which has odzied man

stony phase

intensively!ls can

have had dots simils

Rainfall is fairly

s cMf

2-24

Cambisols predominate, with 1OL_ Lit °cawing on

the steepest slopes- Large , not -on the steepest . lopes,

are eroded and extensive areas of rock ottrop occur. Id areas

harrow terraras cave been constructed, however even on thed soils

are shallow, very stony and depleted.

2,4.4 The d -H.er

Paraht materia"is incude Trap Serles volcanics t card thn'

ic rnotonPs thr t, and felsic Precanor iaî tarlals

the EF.:...-_.1-..... _ area is part of the cc horst arm

A.P.t. ...3,'!.::.,,,, rials are ens-, 'Acularly

i the east a r..risns- ::,:a..',-...,m-i a i 5 ., ':.-. ;."- ..it..ss, -..te over very

diS Strong strurtural influende e. iatensive cultivation

, but

are .:cttest, where,

structural influence is

the soil asSeciation lc Vortisol'. Eutric Nitosols,

- Lovisole and ho.s as of hentral Ethiopia.

Wheu simllar, dli r texture,

but Vartic iertisols Oc:.; cc the , Itter landforms,

ard the east, feis sands suros and limestones

alternate ihht soi develoc, strongly rai'leots tr land

and rainfall as well:, Vartisols

eys in

t 4'1 fly

Eutrit .isois and Rog!,2.1nas on the geoloqi

and man made erosion ard nacen severo. As rai, _11 dreaser. with

desuL, stony lithic Eutrih Lithosi7s

n Hiohiands

end where irt,lcanlcs predominate,

Arenosols, Fluvisols,areas, according to thE

poiraphy and land use atassoiated soils predominate north. of Lake Tana, Vertisols paoireteon tte colluvial slopes of the ar:oa along. the Sudan border, andCambisols very lithic 'Theses, occur ove of the restthe area witii climate. Howevs this patternis not consisent,

2.4,6 SqUthrn-Elale and (the Odade0n.

SoilLimestone,

origin cov.ere -area,

found on the fi olaina of therivers. With rai.fei1 rarely e;(ce - 400 mm, evapotans-irationrates unifom-L high and top'has the doAn: t effect on

Un the vast plains in the a eals ocour ogypsic

accow to weteriqSaline t ::SG3, and Cr-;deposits. On the laArenosols occur, Olt: areathat Eutric and Calci:

'7'..sols and Lithosols all cover substantialrular conjunction o'c !ogy, climate,

iven point, Generally, NitosoL and

-25

b?:.:sement materials, Umestom==s, aic and Upper Paleo7oio sandstonesas well as glacial deposits and n pyroclas-i s. The area hasbeen strongly affected by structural -,Tiovements and topography isextremely rugged. Over a comparatively short distance, rainfalldecreases from a high of over 2 200 mcf: to less than 700 mm. Land useis equally.variable,much of the are,T, -)een intensively cultivatedfor hundreds of years while in other parts dense bush and shrub vege-tation Predominate-

Soils are thus enti Dle over very short distances.Nitosols, Acrisols, Luvisols, VeYtisols, AnCrols, Rend7inas, Phaeczems,

riarentmixed

cf equally thc.ed origin isthe Wabi and the Fafèn

ively flat, materialacrosa region.

nd calcic Xers5:cOs and

Ici-. aha.ses are ,

4 .occur oneastern

so much windblown me

oreeolnate. On thfi2

2.4.7

occurences o l 7i0t t3 anysignifican

On th,-, floVe ,sols occur -Elarzhere salineto ie origin of the afluvum,

Central Har,_, ?ale

Inasd areas transitionalLimestone predominates as pa

stones occur along the SomalirJt direct7 sout the.

deoreases s om 70'd

south. It is this gentle rainfallfor soil differences.

_

ShedelE

an;,

mnnate

on the infr,

2.4.8 Southern

acc6

ane riTestone700 Chron:::a

and

-ges or1.

Soils here are bredndhar,t),' develor,eo.on den ln .-..entheredr the flatt..n.

5

nfall,un basa:

from 400 min

plains n jor riverR, sa1ine phase Chromic-e ollunium has contentrated.

-mr Ola canir Pluvisols occur, accordino

tra

ro rainfallc hoc"Is _,

lcic

itsel tkols.zd its tributaries and

the

the ercner

On the flatter landforms in the south, soils are Eutri,CaisThey are very deep due to the nature of the parent materials. In

addition, large areas of Vertisols are found in numerous basins withseasonal drainage deficiencies. As slopes exceed approximately 15%the rhyolites give way to gneisses and granites. Lithic phaseEutric Cambisols and Lithosols occur on'these materials.

With the increase in rainfall toward the north, Cambisolto an association of VertiL Luvisols on the flatter landforms andChromic Luvisols and Eutric Cambisols on the steeper landforms. OrthicAcrisols and Dystric CambisoIs h. ore common as rainfall increases,

2.4.9 The SouthernRi

This Yrea inc7j he zone from Lake Chew Bahir on the Kenyaborder to tu oka scuI.r cye Geology is complex. Parent

materials include Tertiary py.-clasti,s and Quaternary basalts. Much

of the area 2_.round the numerous Rift Valley lakes is covered by1E,Tustrine deposizs of --;ious origins, Efap-.-ites occur arou :1 Lake

(:T ihir. FinalI-, and gYuitic colluvium c'

Vitric and Moilic occur.throughput, ai thougTarget area5- are fconcent to.the r-v_,rth oflakehave dThoed on ash al.1±, umice laid both as aeril and aslacun Fo: hases are throLighout:And saline'phases . cto -,s ;:.round 'Qua:-:?rra.ry

baza.is outcrcp ti.,nosels and c:,-.:ensive ares mch out.cc.p occ%Jr.

The Rift Valley narrows at Lake Abaya and the very steep topo-graphicTadient :las resulted in extensive colluvial slopes andfans._ 7 'luvium has originated in the fine textured soilsthe volcanics tne hig and , :±v.eau, Chromic Vertisols czcur, -they do rl ano lacustri_e ps.its laiddown on tt. ..,rgins of LE_., Where

Is

eytsive colluVial on the , rtlarlyin southern

in ti,e,s

colt

begir. 1ppear as rai!,,Ifo',1

2.4. 11

7 99

Lithosols, lithic Eotric Regosols and efensiveareas of rock outcrop occur, the :atter often as lava fL. Thereare occasional instances of - o Regosols on the flattest landformsand of Alitric Andosols where lcanic ash deposits are found.

Nor, ----astern Welo, E SLrn Tigray, the Eritrean coast andNo 'arn Eritrea

These arers primarily desert. Parent materials includeTertiary and Quaterns.ry volcanics, colluvium from the highland plateau,aeolian deposits, marine deposits long the EHtrean coast, felsic andmetamorphic Pracamtrian tae.ient ie! .

.thwestern Eritrea and

occasional incluions of licies';or,. Rainfall is. less than 200 mm.Soils are not developed, but.uncoAsolidated deposits do occur as sanddunes, colluvial and alluvial fans bccch sands, all more often

than not saline. Playas, extensive lavo: flows and occasional occurencesof Eutric Reqosois ad Vit ia Andosols are also fad. Rock outcrop

predominates on

2.4.12 k,.rei;.s a di ffe- ent soil " in EthiopiaTable 2 indicates the areal extent in so, kms of the va Loil typesmapped on the Geomorphology and Sails map of Ethiopia. 'T;e percentage

of the total area of the Country cavered by each is aiso indicated.

2.5 PREVIOUS .TUDTES

There are a number of previous soil, land sys.tel and/or landclassification studies of Yarious parts of Ethiopia. The kind, amoUhtand qualft- of 'ne soil vary quite w.::fiely. Few of these studieshave had soil :ng as I. ,, thus much ahi.;:.1cal information inany number of fields is i. in the reports o.f the work.

LOta.tions of thcsOil point samples

:.Sc1ly available studie:.:

Fg!,j',.----sco Soil Map of thP Wo,-1d, Vol.r LeUnesco, Paris, 1977. .The eolls jr En i, arelarger project, at 1:5units are hssociations

asses. soil doe,.

rePort>

2-31

2, Blue Nile River ..in StIdy, BorPau ,nf Reclaim,aArakm, U,S. Departmentof the lioterior, Qpi17rotentialiviaIl 070nithin the b ,

km oa cne thP

land capaility classes 7 ..t,h,= Bur a (7 ale of1:100 000. limited soil data are i--luded in t'

WabiShebelle So:- nRSTROM4 Paris, 197=3 The. 10 000 kjq"." of. . . , . ,

theWaPe Sh,:.:1,-..;:le are me. ...., -.scordi 1 to the FrEd sail classificatijn

.at 1:1.000 f..30. Profile 'ipti and lath:. i . i,:hc7,..;A:.

in the report, The ' - ShPbele and Fafoh .::cPrs

2

at'170 000 and 1 DUO .espectively. Those soil maps cov,-- 33.7

iindo profile descriritions and laboratory. data.

'ihus study areas aaorcairnate densitFigure. 9. The t.r] dseful and

H;11?.d below.

If Africa,part of a witch

The

and s

- cf a.pprcimately

4. of Basit RomP, 1975, Thp 70 000

km2 of the Awash ba.-..-7. to the French ovilclaSsifiCation-System at '1:1 77.7 t 570. k74 thP and

. lower Awash .are mapped at. I: 050 o00:srd 5 020 km' in thP same Preas-

1

Cti

_'51"'

ttP

'1 o

/

*tt

2-3?

1y

3,101;

o0;,70, tiAttett

71'

Ak14.

Res,:-s'i:roe 3

England, 1975.

accordirG to 1.LT

genem.'tosoilBirchafl,

u.

Englarr

for Tnort.

lab

Ailieu

IRAL Paris, 1977.thei ..,stern sher-rna

on the basis ofsoil classificatlodata are inol in t

2-33

-

in the s'eport,by

Terhnica:ices. Ltd.,

:110

for se-ils c .idc

(There , addition 2V7HOUS agencies for soon n

--,sh river, toc '

depts aronnr.'.

9ni.4- o, alihe of La:',,f.e.3

1at1:5° LOU t::Lra1FAO/Unesco I aqend desi

Iaborato: ...a are ' tha

af aetiA1

al Con7-t

an

on Eofls of E hlopia, Murplv, Experiment- _

Station Bufletin No.

le points of ine

s are

puMished, fo:

In a ''tion to tnese,

.ric -:tutio;

:epuhL some 3 500

are a oil mapped

,atiGn. The

;ii ,scrirt, and

tJ an,nt

in

AdeIy

Inc institute foo jltu'r! (1AR1 has carried out

soli su rvcoa nt spme of tx resear:- ttons and has point soil

dai?, Min-ktr :.7rf

*if

soll maps

SOmE?t3r.c aifficult t

interested.

of the

o:A; data

o-5 !,,-x:rces Gf da tseist within

3-1

DEVELOPMENT DF THE GEOMORMOLOGY ANn SOILS MAP

3,1 GEJNEL

A1:1 000 000 scale Geomorphol and Sofia mao in eight sheets andwith extended legend, has bees. cspiled for vJhole of Ethiopia.This activity was in support of e mostee 7s.s use planning exe.ccarried out for the dountvforms an integral :ent

resnurces, essential th su.:applied in, this asseas,,,:can be located on thelimitsland evol

The Geomorphology and Soil.s map also repn, nts an update of therelevant section of thethe World,AES Solln

3,2 MEMO

75feepretation, a lilabla field traverses- ad agroclimaticdata, The relationship h2t-. -:Yrle various inputs and activitiesinvolved in the productioh J; the Geomorphology & Soils map is shown.schematically in the flow chart in Fig:10

ConsidehEble placed or ea -iainiclues toacconsi ish the c a:nd qoila ' humber of

,

interactive fartore whic, although not ihd ' aeculiar to

/YA--ETHillefo 'ioject and..

,:f4-y of Ethiocia5f landthe land eva catidn methodd

, the use of Landsat satellite imagery

p.acape on thelea.,:t as precisa tne scale

! opportunity to site-specificwith approriate agroslimatic informatan...,

Ethiopia, when 4nevitably untIe Lheintentad Putout emote sensing idues

hat b., n

l',11

)1-1

AT

SAT

E

IT F

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L.SI

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AN

T L

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DFA

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TS

The t imtìng .0ccu:s inciuue ..ine foliowind:-

extensive area of the country (1.22 million sq kifis)

limited. accessibility

lack of a comprehensive and si,Iltably letailed nationwide

data base on land resources

limited availability OT equipment and tr , u Jianpower

Lo conduct Integrated surveys

lack of a. suitable 1:l 000 000 scale base map at the

start of project activitIPs

total time available for pnjert output (3f yea-a'

At an early sto in planning overall project activitiea and strateoies,

Landsat was rec iized as 3 desi.rable data base for thP manual generation

and compilation of the 0c-n':. ,rei Soils ma cf ':.---thiopia. The

reasons for this are din Lai the rehul: -a of the envi

master land USP Dian nl -O:orts mentioned a.,...lve. The srale cp.'

presentation of the map s of the master plan are 111 000 WO z i

Therefore, the s.,/.. ..: nature of thr

71 Land,vd,, scries coverinQ Ethnia (see Flgure ) and their inherent.

level of gehization, wia ret6oect to qeomorphic dets-M for example,

are idea1ly ited to the g requireaients,

In contrast, the number of stereoscopic Pafts of conventional aPrial

photographs required to cover the whole of Ethiopia at 1:50 000 socIe

(the scale aienerally aval labia for thP country) is at; :(1) 000,

Although an increased level of landform detail filki , ' delineated

on aerial photoc --,hs of this ..-acale crimpariad th, Lnr:ts.s- ':E.. rE...;i'f:";Pd,

leve7: of generali-,-d lance"..... -.'..etail, exi.st :Ions, the vetly

greater time for conventior-, Thotoihterpral-5tion, res active dates of

coverage (impornnt for lac::: ' . ' ' ' :1 S ''': ES S avIc: the hiQh o.ost of

,.:.

1,!c:iy toPurchasing hat: -- Ev-Ade CON aerlaic0,11.

Landsat iffie-clerv , are )1 tactos -:::::i 4-¡-::

favour of using Lip 7.1.t

time for ot output l'imte;),...

055

r-

Cr.

? "

ET' h.:(

3-4

:1?%4

o\\ buy_

-N,

(-e,*r;-:

e*

,i;d soils ma:-_i it wastdiopia ilable...Nrements, b&c,a

- 1:1 000 000 scale thed the ocssibility of

Figure 10

Landsat index map of Ethiebi&, .ite image c;:xe.s. Marginal

numbers are path'row idetifiers

Prior to cci?)apparent that 1:that time -of the limited topogr c detail shom?.71 Landsat scenes covrir. Ehiopla intr.compiling a converer. 1--ize mosaic -dite?;co'presentationof the level :rild soil a mosaic

was co ructed ? ion At6 ncy (EMA)

and all -geomorphology and soils data wars uompiiod on thisbase. This was later transferred to a ?phic Pas? it becameavailable.

3.2.2 Dev lopment of - units

A basic assumption in the preparation of the Geomorphology and Soilsmap is that geomorphic units delineated by manual interpretation ofLandsat contain recurrent patterns of landforms, soils and vegetation,much as described by Christian and Stewart (1953) for their land systems.Land systems have shown to provide a meaningful base for reconn-aissance level rescurces mapping, at a. scale between 1:250 000 and1:1 000 000, AL such scales the genetically linked subdivisions, orland facetc:, responsible for the recurrent patterns of a land systemand their cOrres: ndingly unique ima .ionatures, cannot usually beseparated. A 1 fcPt may be deflHa, -s an ecosystem within whici.any sampiP site ,ould yield data in nespect of slope, so i, vegetation,parent Material and pther factors which WGU' d not differ significantlyfrom the data relatad facp:,,rs recorded at anothen site in thesame fa,.et

managen.,.:n:;

ation

Imagery interpretatio.

Having first establimorphologi,_

the imagery. These crite.

mapping units. thrugh the use or' existihg data, field traverses, and-ial photographs.

Because of the small scale arh CC: cpCC: ly reduced level ofvisible dP.tail, groups of land terns ratner than individual landsystems are more often appars.,nt an Landsat (Mitchell and Howard, 1978).

-Both individual land systems, where thasP uere mappable, and ciroups ofland systems, forma the basic units f - geo hology and soils mapping

described here. Groups of land 5v5. ......¿ni land systems are

collectively referred to on the GeomorpholOgy and Solis map aslandscape »nits.

1:an,T;:scapa unit as the basic mapping unit,for separating landscape units on

'et of dissection, drainage

facets tant units at the agricultural:i, an at al l ti- s during map compil-

tify and Esterice sig:ificant land facets within

pattern and desity. relief, larf.of landform genesis such as patter:or alluvial din)

ii,-iportant in tes y the valí-ndaries. An iterative ..ss of

inf:ormation on geomorphic utitt senvon ,o c

Jicularly, evidLvolcanic, structural

-lap bet.to sepa-:

lc map overays551 of the same

srs difficulties arose.:ere also indispeils-

traverses. Aftertransferred to

, mosaic she=_:t.

aphic base map -

one for data gener ,s44-

.tion of all relevant existing data,as well as et. nslve field

of the 0ectraverse's in were

, fieldnually c the

reliability of boundary o and '

With these criter-' of cape roits proceeded throughthe manual irrte tior of Croe (ata standard photographic

imagery products of 1:1 000 000 and 1 scales. False colourcomposite and b1ack and white (hands F of each scene

were available at both scales. Delineationq wen., e on clearacetate overlays Ertfach, the 1:1 000 000 scale false colourcomposites. of stereos:.from adjacent orbit pat ed to -1

scape units. -provided on falsescale teThese

able for , - -1

initial ids:nt-ifloa,t1....: of '-the 1:1 00.0 000 seal:: slack whito ratellitP -

This data was subson transfer-en t-the same scale at a

Although Lands arovided thoimportant to ite thatsuch as geolooioi and t01.)-surveys, were necessarySoils map and

3 7

3.2,4 Landscape units

An heirarchial classification system is usd for landscape unitsshown on the Geomorphology and Soils map of Ethiopla. At thebreadest level 12 subd4.visions exist, which are related to tt-'edeneral physiographic Ectr of the landorms. These are as

Seasonal wetland an(i seasonliv water]c.ged landPlains and undulating sideslopesPlains and low plateau'x with hills, modera y dissect&sideslopes and plateauxHills with blainsLow to moderate relief hillsMderalh,, tr hidh rei i et hills, severely dissectedsidPslooe .,:Aate?,ux

High to mountainous relief hillsHicil plateauxModerately dissec plateaux, gac.x with hills androlling to hilly

11, Rubble land and roui, outcrop12. Sand and salt deposits

These 12 subdivisions are imbortaht in relation to the ordering ofthe different mar) units in the not influence the actualmap codes. K4ny of the terms (v=Pd haie a eneral connotation ofsignificance, but are further dPfined below In relrltion to the mannerin which they have been used on the map, bF,,cause o.F the ihe-itableam iguitv In the use of such otherwise general terms.

The- use of such terms in the context of th:b Geomorphology and SoilsmaP legend is therefore explained as follows:

plains; gentij si,.si g:: or flat and which occur predominanbelow 1 200 m elovai Amsl.

- low pThtaboveisolatiom amsl.

inn or ft-t;.brms, u . as mesa-like forms ih

:2atween 1 2no and 1 700

high plateaux; greatly e :scC:,:,y slopir,g ,D, flat landcomprising much of the ,sive of Fthi,:,via, oftendis.ected hy deel-Av ,,..-.. - ivers su ch as the Blue Nileand generally stand-*:nq ii:tions ,11:::,3 e 2 000 m amsl, butoccuring in the range 1 /do- 00":.; m c,:r,,T,

low ,:'1) 71-,3derate rt=lief hills; h711c, Ctb netr re7ief differencebwe,-,n the crests of the Mlls arc" oct'c.ams of interveningvalleys of less than 300 m

moderate to hiah relief hills; hiOs with a 1-.;:!andifferenc between the crests of the h.P.1s he. bottomsof inter. valles of bt.*,: ""),u,,) m

high to m6,Jntainous relief h-r:'-= hills and mountains witha mean relief difference be,-. the cres of te hills andmajor intermontane valleys ot y greater than 700 m

Terms such as rolling and hiny foi low the values given in the FAOpublication Guideline for Soil Profile Description-(1977), and referto the predominant land for-m characteristics of the land-scape unit descrihed.

3.2.4.1 Landform genesis

Within each of the 12 broad of I ondtoniss six furtn,dIvisiona are possible, 11 do not al vs occur in ea-oh of theprecedihg ma.';or classes. Tese six subdivisions reflect the genesisof .:e Iandforms and include the following clase:

Lan, 111 gen si,7 Code

AlluvialAeolian

Volcanic

Structural.Res 7?

These a',,,, the codes indice,teri on theEthiopia for the various fflaD unIts,

. ;:y and Soi'L

9

Usin - two levels ,:., i i t...c.. t..., di,..-

.,,,-rphic

t, _ identified :punt!, Euh f the Aliuvial, !leollan,"--LV poi- and Volcanic -- nf

The suffixe,..

are

Volcan'!-:

Fels-

3-9

on the map by twc,sand

nd Vn fdsssto 4enoti and rPt

a t-tal of t.;'-

etc)

et'e)

.

Geomorphir- :ts. are further subdivwhi-'

Thb subO,l

jj to,L,

fer n -

.,:nds_uou. unit

and newly generateri soil

-

LUut=

C:

- nr%

Sh.

rr,,g4n of ti

ht,7,is of soil asso,iiations' led

The Choice of soil paramet2rs in this cha -;terization wasdetermined by 'land evaluationThese parameters are discusSed ir the

In the case of Ethiopia, there is a considerable amount . f existingsoil data (see chapter 2 ) although i'iuch is of uneven quality or ofinexactly described location, or 'aetc,. Data for over 3 500 point samplesexist, approximately 30% of the count.ry has been surveyed and mapped ata reconnaissance leve] and a number of detailed and semi-detailed studiesof very limited area have been complet,2d. This work has been done byvarious government and international agencies, consulting firms andindividuals. In addition, a u 000 000 soil map exists, as part ofthe FAO/UNESCO Soil Nab of the World (1977).

The processing of these data was complicated by a number of factors,Both point data, and to a tesser extent the survey fragmentary.Rarely are th2 a1olric nPsultu,,,r, or H 2ite re thevexist, 2nough to pr:. .,puisite in7o:ta Ha. 1h

difficulUie arose both in soil (for mappin0 and inquantification of land charaoteristics and qualities (for the landsuitability evaluation leadind to thh, MLUP), Most of the point data,for examoie, are for surface soils and 1,1.e -pnly rolorr, texture,pH, organic matter and total nitrogen per- litativ2estimates of exchaaqeable cations. Anal:. re hot -izad and, frequently are not ,-...nnibPd. have been cae..sThed,

various classification systes have been used..

Before data were asii h individual lan,q,7c ,nits, exi -sample si tes had tu +k,,,, 1.1 rho,ne , , , - , :naps,

locations .nera,.. in only very fo,as "38 kms we,st oF Ambe, Once located, theon the geomorphic deliheatio, generated from Landsat, Points fahfliwithin each landscape unit ,...sed to characterize, by domina:each major facet within each unit.

nt data were ovc:laiO

3.2.5

dhistind reconnaissonrated botihs:.H

ehch otheof imges atretathe Landsatthe reconnaissancdtheir constituent fa,ats.

!he

oation o'

in a LOSe, sovn

point tn locEti:.mord

anproximateata, it

n

for cnthn wit

observtion and. and by

PO

field stuiesusi-7 total '1-'.!1

ofacT. the

3-1 I

Ahg

; cont,

td Soils c;:it

The Landt9cheally approxiate

interpretatioah boundaries -

ihg. In adinfo on th::

the brean these nnits into

4aai association required,ale , the

-ne oftenba, . ire to

, pointsall this iunits. Fackn.

itself.. Th,s

locations, by nieldtiofl.

it

s. At 7_ DO'

'r.-='ri(311 vgar,s.

itleo od existiksoil inform,:tion er .fltblr-. for similar

main ado, as indneSoiL

ta or i

'reents of tne Iendata requirements of thecounte of the project and

' ta stand as anbr:gind:

by the possibility otfuture for soils

,s

kiiuS by area. cif the

significant land facets ar-

Two *ant fo,

-;:acets

the s:'-me unit mat

in

of the fac

in a

in doing tsoi

on. rne

data in excees pi' the floa

This comes

.Tven

' the saner -ets can occur

oaks de

further redyhTheti

tterito,i data LIS in the

rY.

thu =ac.,,ns don tr hed in diierent proportions can

'iandfer onits

des., rption tThich is esentoa to enifuctive

nnly

in rlation

s as zed. at thia no:

Remer"

(by

Of'

Landscape uit No,

Geomor,

requi,r

outsPt. of

HstberrDi

'1-14

Totl

Sit:inifcant

()

g..

Peoes c:: y for

3-15

The various combinations of these factors repeat themselves acrosssignificant land facets of different landscape units. This factcoupled with the need to simplify land evaluation inputs on landformand soils to make the task of manual suitability matching moremanageable, led to the identification of SMU's.

jr

7

7

3-15

Sn 11 -.:11'`b:;r;. ;,-,,,!

Guidelino fop

Rir andL s!;b-00..,twoperin-6

:t.eo.F.4y

TLI

LWSCAPE UNITS1..Fs'AEND

; I on:MU W40 Of

',61xture

f:y¡- 3- 10

10 - 50

60 - 9t)

World

; SI I SC211 CO10111- ?.:it,Fi;-".

. '1r! "'; 1%*- _

1.;tv.,-,

' Thr.tt,

oc,corP,lig

fcy

4-1

CijAP-7R 4

DETAILED GEOMORPHOLOGY AND ASSOCIATED SOILS OF LANDSCAPE UNITS

4.1 INTRODUCTION

The fol/owing chapter illustrates the detailed nature of thevarious geomorphic subdivisions included in the legend of theGeomorphology and Soils map of Ethiopia, together with a summary ofsoil associatations which characterize them as particular landscapeunits.

The chapter is divided into two main parts. In the firstsection cross-sections of the various geomorphic units are given,followed by landform and soil summaries by significant land facet.The cross-sections are arranged in elphabetical order for easyreference, for each of the main leoorm genesis,types which includealluvial, residual, structural and volcanic landform types. Cross-sections are only inteloe indicate the general form of the leridsc6peunits and are not drawn to either a strict vertical or horizontal scale,but to approximate secles.

Plates used to illustrate the image signatures ol geomorphictypes on Landsat provide details of a selection of landscape unitsfor comparison, and are included to provide a more complete under-standing of the characteristics used to separate the various geomorphictypes during the image 'analysis stage and in the construction of theGeomorphology and Soils map legend.

Ab - Basins and depressions with seasonal drainage deficiencies

2260

2240

2220

4-2

5 Km

S opes of colluvial margins in Ab3 are 0-2%

NUMBER 2

FACET basin plains colluvial marginsAREA (,) 90 10

SLOPE (%) 0-2 2-8

SOIL

Ab1 Pellic Vertisols Eutric NitosolsAb- Pellic Vertisols Dystric NitosolsAb Haplic Phaeozems Vertic Cambisols

Ac - Allu

Ac'

NUMBER

FACET

AREA (%)

SLOPE (%)

SOIL

MC

9Ac-

Ac-

Ac4

ia olluvial slopes and outwash fans

1

Chromic VertisolsEutric FluvisolsEutrie FluvisolsCalcic Xerosols

(saline phase)Orthic Solonchaks(petrogypsic phas

Orthic Solonchaks

Chromic VertisolsEutric F1uvi5,7)(stony ph,e)

Vertic Cambisols

A - Deltas

1200

4-4

i220

2i0;

r2

Se3501liaiwOer 14r e

;C: *Km

NUMBER 1

FACET alluvial plains seasonal swamps pc.rm*nt swampAREA (Z) 40 40 20

SLOPE (%) 0,2 0.2 0,2SOIL

1

Ad Chronic Vertisok Eutric Fluvisols n,a.Ad4 Eutric Fluvisc- Eutric a.

(saline phase) (saline phase) n.a,

3 2

Af - Alluvial fans and bajadas

NUMBER

FACET convex fan slopesAREA (%) 80

SLOPE (%) 2-3

SOIL

AfI Eutric FluvisolsAf2 Eutric Fluvisol-Af3Eutric Fluvisols

(saline phase)

4-5

5 Km

braided channels

20

rubble landrubble landrubble land

Co-41LIxes or eroded residual I of'l 1 t crate re ief and.;iltersoe',.sd fan deposits.

civ

AV:

Lithot'ols

Li tiVY.'

Lithosols

Km

Fluvisols

°°c Fluviso s

A

1

relief hills convex fn-ope braided channels50 40 i0

8-16 2-8 2-16

Ak - Coastal margin plains

0

5

4-7

7

FACET unduL7tingcoastal ;Jains

coaF,t;)! mArshes

AREA (%) 50 30 20SLOPE (S) 0-8 6-2 0-2SOIL Orthic sand

Al 7 Lacustrine and fluvio - lacus

1520 ,-

1510

1500

Fluvio-lacustrine plains are seasonally flooded in All

I490

7 Km

NUMBER 3

FACET fluvio-lacustrineplains

col1uvi61 maroins marshydepressions

AREA (%) 60 30 10

SLOPE (%) 0-2 0-2SOIL

Al1 Chromic Vertisols Chromic Vert i sol s Eutric FluvisolsA12 Chromic Vertisols Chromic VertisoIs Chromic VertisoAl' Eutric Fluvisols Moilic Andosols Eutrir Fluvisols

(sodio phase) (Sodio phase) (sodic phase)

4*8

a-ins

Am - Meander belts of major rivers

Am4

- 5

8;'0 r

r

f305

NUMBER

FACET

AREA (%)

SLOPE (%'

SOIL

Am

Am

1

flood plains andlow terraces

60

0-2

Eutric FluvisolsEutric FluvisolsCalcaric Fluviso S

(saline phase)Eutric FluvisolsCalcaric Fluvisols(saline phase)

Eutric Fluvisols

4_9

5

* Marshy depressions are permanently wet in Am'Chromlc Vertisols (saline phas.a) occur on low

marshy depressions

20

0-2

'Calcarle.

ct

Fluvisols(saline phase)

Eutric FluvisolsCalcaric Fluvisols(saline phase)

Eutric Fluvisols

levees

20

0-2

Eutric FluvisolsEutric FluvCalcaric(saline phase)

EutricCalcaric(saline phase)

Eutric FluvisDis

4-10

An - Dry river channels of aentle slope with seasonal flow in most years

NUMBER 1

FACET n.a.AREA (Y.) 100

SLOPE CO 0-2

SOIL

An' Chro,ic Vertisols(saUne phase)

An2 Eutric Fluvisols(saline phase)

Ap - A luvia lains

NUMBER

FACET

AREA (%)

SLOPE (%)

SOIL

Ap1

Ap2

Ap3

4Ap

Ap

Ap

Ap7

805,

60( L.

4-11

plains and low terraces80

0-2

Chromic VertisolsEutric FluvisolsOrthic Solonchaks(sodic phase)

Vitric Andosols(sodic phase)

Eutric Cambisols

Eutric FluvisolsHaplic Xerosols

IC KT

2

seasonal marshes

20

0-2

Chromic VertisolsEutric FluvisolsGieyic Solonchaks(sodic phase)

Eutric Gleysols(sodic phase)

Eutric FluvisolsEutric FluvisolsEutric Gleysols

2

Plains and low terraces are seasona ly flooded in Apl

As - Seasonal swamps and marshes

rn

-720 -

t7r:,

1705

2

4-12

Wet season Dry season

water eve water level

1700

5 Km

NUMBER 1 2 3

FACET seasonally inundated gently sloping permanent

depressions margins marsh

AREA (%) 70 20 10

SLOPE (%) 0-2 0-2 0-2

SOIL

As1 Eutric Fluvisols Eutric Fluvisols n.a.As2 Calcaric Fluvisols Calcaric Fluvisols n.a.As3 Chromic Vertisols Chromic Vertisols n.a.As4 Gleyic Solonchaks Orthic Solonchaks n.a.

Av - Voicano-lacustrine plains

NUMBER

FACET

AFEA (%)

SLOPE (%)

SOIL

Av

1

lacustrine plains

80

Vitric Andosols(sodic phase)

Orthic Solonchaks

Luvic Phaeozems(sodic phase)

Lacustrine plains make up

4-13

2

lake fliarginq

10

Eutric Fluvi

3

colluvial margins

10

Eutric sol

Eutric Fluvisols Eutric Cambisols(saline phase)

colluvial margins 20% of Av2

-4

Lacustrine plai ake up 100% ot Av-

1608-

1604 r

1600

NUMBER

FACET

AREA (%)

SLOPE (%)

SOIL

4-14

A - Permanent fresh wa and marshes

Ay - Small closed basInsalluvium, co luv u

4-15

esions of the Afar triangle"te deposits

5 K m

NUMBER 1

FACET graben valleys playas

AREA (%) 80 20

LOPE (%) 0-2

SOIL Orthic Solonchaks Orthic Solonchaks(petroqypsic phase) (petrogypsic phase)

rn

3 0

1 K rn

NUMBER 1

FACET n.a.AREA (%) 100

SLOPE (%) 2-30

SOIL Sand surface

d d nes and sai -ncrusted san deposits

505

500

4-

5 Km

NUMBER 1

FACPT n.a.AREA (%) 100

SLOPE (%) 0-8OIL Orthic Solonchaks

(petroaypsic phase)

Ec Evaporite pediments ed alluvium

El - Brackish playa lake- and marshes si , in enclosed basias or at

inland termination of blind stp,

510 r.

2

4-18

Km

1

FACET playa lakes and playas

(%) 80 20

SLOPE (%) 0-2

SOIL na Solonchaks(vi,trogypsic phase)

Ep - Playas and salinas

500

NUMBER

FACET. n.aj:TEA. %) 100

SLOPE (%) 0-2

SOIL Orthic Solonchaks(Petrogypsic phase)

,

5 Km

4-20

Ra - Hilly olaios comprised of undulating plains and low plateaux witha substantial proportion of moderatff to high relief hills

15 cri

NUMBER

FACET undulating plainsand low plateaux

rolling plains andlow plateaux

moderate tohigh relief hills

AREA (t) 60 20 20

SLOPE (t) 2-8 8-16 16-30SOIL

Ra Haplic Xerosols Haplic Xerosols Lithosols(stony phase) (lithic plase)

Dystri- Nitosols Dystric Nitosols Orthic Acrisols

4-21

Rb - Dissected lowland Elains and low piateaux

ic Kft,

NUMBER

FACET incised valleys2

rolling plains andlow plateaux

3

undulating plains andlow plateaux

4

hills

AREA () 40 40 10 10

SLOPE(%) 30-50+ 8-16 2-8 16-30

SOIL

Rb1 Lithosols Chroniic Luvisols Eutric Nitosols Chromic Luvisols

Rb2 Lithasols Chromic Cambisols Chromic Cambisols Lithosols

1

Rbc Lithosols Cicc Xerosols Orthic Solonchaks Lithosols(lithic phase)

Rb2 Lithosols Rendzinas Haplic Phaeoiems Rendzinas(lithic phase) (lithic phase)

Rb Lithosols Eutric Cambisols Eutric Cambisols Lithosols(lithic phase) (stony phase)

NUMBER

FACET

AREA (

SLOPE (%)

iftPd re fs

SOIL ric Regosol se)

4-22

Km

SD1L

4 2 3

Rd - Undulating to rolling lowland plains and low plateaux

D,4 Dystric Nitosols Dystric Nitosols Orthic Acrisols Lithosols

Rd' Cnromic Luvisols Chromic Luvisols Chromic Luvisols Lithosdis(stony. phase)

Rd2D

Dystric Nitosols Dystric Nitosols Orthic Acricsols LithosolsRd- Eutric Nitosols Chromic Luvisols Chromic Luvisols Lithosois

A,

IA9

Haplic Xerosols Haplic Xeroso1s Lithosols Lithosols

Chromic Cambisols Chromic Cambisols Lithosols Littiosols

Calcic Xerosols Calcio Xerosols Lithosols Lithosois(lithic phase)

Rd2 Eutric CaWsols Calcic Camhisols Lithosols Lithosols(lithic phase)

Ro3 Orthic Solonchaks Calcio Xerosols Lithosols Lithosols

Rd4 Chromic Cambisols Chromic Cambisols Ehtric Camblstis Lithosols(lithic phase)

Rd' Cambic Arenosols Cambio Arenosols Li1Jhosols LithosolsRd' Chromic Cambisols Chromic Cambisols Lithosols Lithosols

,d-Chromic Luvisols Chromic Luvisol: Chromic Cambisols Lithosois

ka Gypsic Yermosols Gypsic Yermosols thosel s Lithosols(saline phase) (saline phase)

kAl Chromic Luvisois Eutric Cambisols Eutric Cambisols Lithosals

2(stony phase) (11thic phase)

Rd' Eutric Cambisols Eutric Regosols Lithosuis Lithosols(lithic phase)

Chromic Luvisols Eutric Cambisols Eutrir Cambisols Lithosols(stony phase) (lithic phmse)

Iii

i%tumder1 2 3 4

FACET undulating plainsand low plateaux

rolling plainsand low plateaux

hills incised val leys

AFEA N 40 40 10 101,EOPE 2-8 8-15 16-10 30-50+

/V - Undlatino to rol)ing lowland plains and 1c)'w platnuxld'isseted lavw; e.,:tIms=ve rock outcroP

600 i--

550 1-

60 0

4 - 2

i

NOMBER 1 2 3 4.r., 6

,..induiating plains rollit.9 plans ston; trraces hills dissPctod va.lisvs undulatiml30 30 10 30 ,::: 10

,.:. 00 2-8 8-14 2-8 16-30 30-40+ 2-gCalcic Xerospls Cohat: Xertr,ols Ru!-Jhe land Hthobls L i those i s Cakic '..,.erilsols(petrocalcic phase) (lithic phase)

4

Pf - Undulating siAnslones and edoont znne hdiy influenced by cd;luva!_pro.des_ses.hut,),etainingdistinct residual characteristics

NUMBER

FACET

APEA C::)

SLOPE

SOIL

d,1

pf2''v

6

Rfy

Rf'

Rf-

Rf3

Rt9

Rc

2

Rfc

Rf3

Pfc/e

Rf1

Rf-

Rfe

m

Pfu!

1550 -

)500

05 7

14i;e

1350

42

undulating sidesIopes90

2-8

Chromic Vertisols

Chromic Vertisols(stony phase)

Cnromic Vertisols

Mollic Andosols

Eutric Redosols(lithic phase)

Dystric Nitosols

Haplic Xerosols(stony phase)Oystric Nitosols

Eutric Cambisois

Eutric Hitosols

Vertic Carrb)sols

Chromic Vertisols

Orthic Soloocnal4s

Eutric Regosols

Orthic Solonchaks(petrogyosic phase)

Eutric Redosols

Chromic Cambisols

Orthic Solunctlaks(petrogypsic phase)

Chromic VertisoIs

Ver-tic Cambisdis

Haplic Xerosols(stony phase)

Vertic Cambisols

2

Eutric Uitosols

Eutric Redosols(lithic phase)

Orthic Luvisols(stony phase)

Eutric Cambisols

Lithosols

Dystric Nitosols

Lithosols

Dystric Nitosols

Eutric Cambisols

Chromic Luvisols

Calcic ramnisals(lithic phase)Calcic Cambisols(petrocalcic phase)

Lithosols

Calcic Xerosols

Lithosols

Eutric Rendsols(lithic pnase)

cambir Arenosols(litera phase)

LithosoIs

Eutric Nitosols

Eatrir Cambisols(lithic phase)Lithesols

Eutric Cambisols(lithic phase)

Pg - Major river gorges. canyons and escarpments[toy ;Thli. t T

1nRgy very steep sldoslopes make up 40 persent ano plateauterraces occupy 33 percent of the u5-iit

40 km

NUMBER 2 4 5

FACET very steep sideslopes plateau terraces steep sideslopes gorge's bottom escarpments

ARFA (%) 30 30 20 10 i0

SLOPES ('X) 30-50+ 8 -15 50+

SOIL

Rgv Lithosols Futric Cambisels Eutric Cameisols Eutric Cambisols Rock surface

(stony phase) (lithic phase) (stony phase)

Lithosois Eutric Canhisols Eutric Cambisols Eutric Cambisels Rock surfaceRri-0 (stony phase) (lithis phase) (stony phase)

Rgc Lithosois Pehdzinas Penarnos Eutcic Cambisole

(Iithic phase) (lit)ìic phase) (stony pnase-f

Re-s

Lithosols Cambis Arenesois(stony phase)

Camtlic Arenosols(11thic phase)

Ca*)ir Arenosols(stony phase)

Rock surfaso

Rg. Lithosois Eutric CaWsols Entrie Pambisols Eotrjc Cainbisols Rock surare(sony phase) (lithic phase) (stony phase)

Rh

- H

iyh

to m

ount

aino

us r

elie

fhiris

3C,O

G

e,00

2200

-5,7

)".

3352

51,

,

NU

.13E

R3

45

6

FA

CE

Tve

ry s

teep

sid

eslo

oes

stee

p si

desl

opes

mod

erat

e si

desl

opes

plat

eau

terr

aces

and

gent

le s

ides

lopa

sin

term

onta

neva

lleys

esca

rpm

ents

AR

EA

N50

1010

1010

10

SLO

PE

N30

-50+

16-3

08-

162-

80-

880

+

SO

IL

Rh1

Chromic Luvisols

Chr

omic

Luv

isol

sE

utric

Nito

sols

Eut

ric N

itoso

lsE

utric

Flu

viso

lsR

ock

surf

ace

(sto

ny p

hase

)R

h2

Ort

hic

Acr

isol

oO

rthi

c A

cris

ols

Oys

tric

Nito

sols

Dys

tric

Nito

sols

Dys

tric

Flu

viso

lsR

ock

surf

6ce

(sto

ny p

hase

)3

Rh

Lith

osol

sE

utric

Reg

asel

sE

utric

Car

eiso

lsE

utric

Cam

biso

lsE

utric

Cam

biso

lsR

ock

surf

ace

y(li

thic

pha

se)

(lith

ic p

resa

)(li

thic

pha

se)

(sto

ny P

hase

)

Rh4

Eut

ric C

ambi

sols

Eut

ric C

ambi

sols

Ort

hic

Luvi

sols

Eut

ric N

itoso

lsE

utric

Flu

viso

lsR

ock

surf

ace

(lith

ic p

hase

)(s

tony

pha

se)

(sto

ny p

hase

)(s

tony

pha

se)

(sto

ny p

hase

)

Rh5

Lithosols

Lith

osol

sE

utric

Cam

biso

ls-li

thic

pha

se)

Eut

ric C

ambi

sols

ston

y ph

ase)

Eut

ric C

ambi

sols

(stony phase)

Rock surface

Rhyls

Eut

ric C

ambi

sols

(lith

ic p

hase

)

Chr

omic

Lav

isol

s(s

tony

pha

se)

Chr

omic

Luv

isol

sC

hrom

ic L

uvis

ols

Eut

ric F

luvi

sols

Roc

k su

rfac

e

Rh1

Dys

tric

Cambisols

Ort

hic

Acr

isol

sD

ystr

ic N

itoso

lsD

ystr

ic N

itoso

lsD

ystr

ic F

luvi

sols

Rock surface

(lithic

phas

e)

Rh2

Chr

omic

Cam

biso

lsC

hrom

ic L

uvis

ols

Chr

omic

Luv

isoi

sE

utriz

Nito

sols

Eut

ric F

luvi

sols

Roc

k su

rfac

e(li

thic

pha

se)

Rh3

:lock

sur

face

Lith

osol

sLi

tho:

ols

Hap

licXerosols

Eut

ric F

luvi

sols

Roc

k su

rfac

e(li

thic

phase)

Rh4

uLi

thos

ols

Lith

oso'

.sC

hrom

:c "

1am

hiso

1s(li

thiL

pha

se)

Chr

omic

Cam

biso

lsE

utric

Roc

k su

rfae

e

Rh_

L)th

osoi

sE

utric

("-

amb.

isol

sE

utric

Car

chis

ols

Eut

ric H

uvis

ols

Ror

k

(lith

,

Pi Higl) reli,- hills and mountains with a substantjal pr ortion ofmodejTa_tejy,s1,opi_ngyalleys i'iyterspersed throughout

3000 r

4-28

Eutric

4

high relief hillsand mountains

10

16-30

Li-0C o``C

15 Km

NUMBER 1 2 3

FACET hioh relief hillsand mountains

f -tslopes valleys

AREA OD 50 20 20

SLOPE (%) 30-50+ 8-16 0-8

SOI!

Ri Lithosols Futric Pegosols Vertic CambisolsV (lithic pase) ilithir phase

RjV

fl4Rjg

Ri-c

yjnor river Qorges and ravines

2000t

NUMBER

FACET very steep side slopesAREA (%.) 50

SLOPE (4) 30-50SOIL

Lithosois

Lithosois

Lithosois

4-29

10 Km

Rock surface

Rock surfacp

Rock surrcice

Eutric Fluvisols

Fotric Fluvisols(stony phase)

Calcaric Fluv-kois(stony phase)

escarpments (Jorge s bottom40 10

50+ ?-4),

2200;

2100

2000

L900 -10 e.m

NUMBER 1

FACET undulating plateaux modera te relief hils ceasonel corshesAREA (2) 50 30 20

SLOPE (2) 2-8 16-30 0-2

SOIL

lRkV

,Dystric tosols Dvstric Nitosols Qystrlc Gleyscis-?.

Rkv Chromic Luvisols(stony pnase)

Chromic Luvisols(stony phase)

ChrOglic Vertisols

Rk High x lith scattered modera-e rPlief hills and sudstantiaiareas of seasonal marshlan0 iryte,rspered throucfnut

R1 - Low to moderate relief hills

2200,

rn

NUP8FR 2 3

FACET sideslopes small v'tleys steep sidesis. s plteau terracesand gentle sideslopes

AREA 0.) 60 20 '10 10

SLOPE (1.) 8-16 0-8 16-30 2-8SOIL

Riv

Eutric Nitosols Chromic Vertisols Eutric Nitcsols Chromic Vertisols2RI-v Eutric Cambisols Eutric Cambisols tjthosols Eutric Cambisols

(stony phase)4

V Orthic Luvisals Chromic Vortisols Orthic Lovisols Orshic tuvisols(stony phase) (stony ase) (stony phase)

1

41ii Enteric, Cambisols Vertic Eambspls Eutric Peghsols Eutrio Cambisols

(lithic phase) (stony phase) (lithic phase) (stony phase)

'''''v Lithosols Eutric Regosols Lithesols Futric Regososi(salino phase) (litric phase)

RI ,vie Lithosols Orthic So1onchks(stony phase)

Lithoscis Eutric Regosols(lithic Olase)

,

W.2

Oystric Nitosols Oystric Nitosols Orthic AcrisoIs Dystrio Nitosois

R1-g

a

Chromic Luvisols Vertic Luvisols Chrcmpio Luvisols Eutric Nitosols

R1U

Haplic Xerosols(lithic phase)

Haplic Xerosois Lithosols haplic Xerosols(stony phase)

R14g

Eutric Cambisols(lithic phase)

Eutric Camh sols Lithoso'is Eutric Camhisols

riil Calcic Xerosols Orthic Solonchaks Lithosols Calcic Xerosols(lithic phase)

R14', CdIcic CadoisoIS Chrcmic Vertisols Lithosols Calcio Camhisols(lithic phase)

(n2'e

Calcio Xerosols Cutrio Regosols Lithosols Calcio ((erosols(lithic phase)

Hapiic Phaeozems Chromic Vertisols Eutric Cambisols Haplic Phaeczems,lithic phase)

Lithosols Eutric Reclosels Lithosols Eutric Pe5osois(stony phase) (stony phase)

p' Cambio Arencsols Chromic Cambisels Camhic Arenosols Chromic Cambisols(lithic phase) (lithic phase)

RI Cambio Arenaseis Chromic Cambisols ;Ithosols Cambic Luvisols(lithic phase) (lithic phase)

4Chromic Luvisols Vertio Lhviaols Chromic Camtisols Chromic Luvisols

RI Gypsic Yermosols Orthic Salano. s tithesols Gypsic Vermosols(saline phase) (petrogyp5io . (saline phase)

Eutric Nitosois Chromic Vertiols Chromic Lhvisols Eutric Nitosols

RI Eutric Cambisols Eutric Cambisols Futric Cambisols Chromi,- Luviso1s

(stony phase) (lithic 0105e), 3

Haplic Xerosols li011 10Xerosols tithosols Haplio Xerosols(lithic phase) (stony phase) (stony oha'a0

Eutric Nithsols Chrmic Vertisois Chromic Luvig,:ls Futric Nitosr(ls

2400

220:0

2000 -

2 4

¡UNDER

'ACET very steep sideslopes steep sidoslopes

R^r

3 a

mderete sideslopes small valleys plateau terreros arm)yentle sideslopes

',REA (N) 20 20 10

a...OPE (C) 30-50 16-30 8-16 0-8 2-8

)1sn' Chromic Luvisols Chromic Lnvisols Chromis LoY:isnis Chromic Vertiso1s EntrMo Nitosols(stony phase) (stony phase)

Orthic Acrisols Dystric Nitosols Dystric Nitusols Dystric Nitosols hystric Nitosols

Orthic Lovisols Orthic Luvisols Orthic Lovisols Eutric Nitosols Eutric Nitosois(stony phase) (stony ohase) (stony pisase) (stony phase) (stony phase)

Lithosols Lithosols Lithoso1s, Eutrio Redosols(stony pil'iase)

Eutric Redosois(iithio Phase)

Lithoso1s Eutric Eutric Camhiso1s Vertic Camhisols artric Cambisels(litkic phase)

Pm6 Lithpsols Lithosols Entric Cambisols Eutric Cambisols Etitreic Cambisok(lithic phase) (stony ocaso)

Ñfl Lithosols Eutrc Rogosols EhAtric Cambisols Eutric Cambisols Eutric Cambisolsthis phase) (lithic phase (stony phase) (1ithic phase)

Rmvi,,e

Orthic Acrisols Orthic Acrisols Dystrlc Nitosols Dystric Nitosols Dystric Nitosols

)1),F.,,xs Eutric Cambisols Chromic Luvisols Chrmtic Levisols Vertic Levisols Chromic Lhvispls(lithic phase) (stony phase)

Re' Orthic Acrisols Orthic Acrisole Dystric Nitose1s Dystric Nitoso1s Dystric Nitosols

Chromic Cawcisols Chromic Luvisols Chromic Loyisols Vertic Luvisols Chromft Lnyisois(ifthic phase) (stony phase)Chromic Cambisols Chromic Lovisols Chromic Luvisols Vertic Luvisols Ehtric Nitosols(lithic sisase) (stony phase)

Lithosols Litesols Haplic XprosolS Orthic Solunchaks Eirtric Reqesols(lithic pisase) (saline phase)

Rh; LithoscIs Li these; s C'oromic Cabisols Chromic Cambisols Chromic Camoisols(lithic phasP1

Lithosols Lithosols Calcic Cerosos Orthic Soloachaks Ca1oic Xerosols(lithic phase)

Lithosois Lithsols Calcio Cambisols Chromic Vertisp1s Eutric Cambiscis(lithic phase) (st8ny pase)

2Lithosols Lithosols Calcic Cambisols Calcaric Fluvisols Chromic Cambisols

(lithic phase)

Lithosols Eutric Cambisols Haplic Phaeozems Chromic Vertisols Haplic Phatnexzems(lithic phase) (stony phase)

Lithosols EutriJc Cambisols HapIic Phaeozems Chromic Vano SOIS Haplic Phaeo2ems(lithic phase) (stony phase)

Lithoso)s Cambio Arenosois Camhic Arenosols Chromic CaOisols Chromic Cambisais(lithic phase) (lithic phase)

Lithosols Lithosols CiRio Arenoso1s Chromic Cambisols Cambic Arenosols(Wahic phase)

Lithpsols Lithosols Gypsic Yermosols Orthic Solonchaks Gypsic Yermosne(petrogy.osic phase) (so/ine phase)

, em) Lithosols Eutric Cambiso)s(lithic phase)

Eutrio(Sto;;

Eutric Emambisols Chromic Luv1)).).:s

Pm)ír,

Lithosols Lithosols UaOli2 X2 Naplic Xerosols Haplic Xerosols(stony phase) (lithic phase)

Lithoso1s Eutrio Cambisols - Eutric i> Visos Chromic Luvisols(lithic phase)

L1thosols Lithoso1s s H5pli. o Xerosols: (li sic oheae)

A.....

s - Moderate to hiqh relief hills 4-32

4-33

Rn - Hilly plains comprised of undulating plains and low plateaux with a substantialproportion of low to moderate relief hills

601v

Eutric Nitosols Eutric Nitosols Chromic Luvisols

Rn2va

Dystric Nitosols Dystric Nitosols Dystric Nitosols

Rg:' Eutric Pite-sois Orthic Luvisols Orthic LuvisoisAi (stony ;ii,asei (stony phase)

Rn4v Eutric Cambisols(stony phase)

Eutric Cambisols(stony phase)

Futric Cambisols(lithic phase)

RoSv Lutric Regaseis(lithic phase)

Lithesols Lithosols

'RA' Haplic Xerosols Haplic Xerosols Lithosois

9 (lithic phase)Rn2 Dystric Nitosols Dystric Nitosels Orthic Acrisols

9a

RFC' Chromic Cambisols Chromic Cambisols Lithosols9i

an' Eutric Nitosols Chromic Luvisols Chromic Lou aalsM9

cCalcio Xerosols Caicic Xerosols

(lithic phase)Lithosols

Pg2- c Eutric Cambisols Calcio Caitiisols(lithic phase)

Lithosols

Rn- Haplic Phaeozems Haplic Phaeozems Eutric Cambisols(lithic phase)

Q1.1 Cambie Arene-sois Cafraiic Arenosos Lithosols(lithic phati)

a

Eutric Nitosols Eutric Nitesols Chromic Luvisois

Ro' Chromic Levisols Eutric Cambisols Eutric Cambisols(stony phase) (lithic phase)

, 3Hu Haplic Xerosols Haplic Xerosois

phaLithosels

NUMBER 1 2 d

FACET ondulatiap plains re-ilion, plains and low to moderateand low plateaux low elateaHx relief hils

AREA (S) 60 20 20

SLOPE (%) 2-8 8-16 16-30

SOIL

Ro - Hilly terrain of low to moderate relief writh a subtantial proportion of moderatelt

NUMBER

FACET low to mOdPratarelief hills

AREA (%) 60

SLOPE (A 16-30

SOIL

Ro1 Nithosols

Ro Dystric Nitosols

Ro3 Chromic Luvisols(stony paso)

Ros

sloping valleys interspersed throughout.

1800

300

Eutric Cambisols(lithic phase)

L thosols

Lithosois

Chromic Lovisols

Eutric Cambisols(lithic phase)

Lithosols

valleys

0-8

Et:trio Regosols(stony phase)

Dystric Nitosols

Chromic Vertisols

4

RoyEutric Cambisols Vertic Cambisols(stony phase) (stony phase)

5

RovChromic Luvisols Chromic Vertisols

Rol Orthic Acri sois Oystric Nitc, olsQ

2Ro Luvisols Vertir Luvisols

Ro3 Lithosols Haplic Xerosols94

Ro' Lithosols Chromic Cambisols

Rol Lithosols Orthic Solonchaksc

Ro' Calcio Cambisgls Vertic Camhisolsc (petrocalcic pnase)

Chromic Vertisols

Eotric

(salina phase)

Orthic Soionchaks(petroeypsic phase)

Chromic Vertisols

Eutric Cambisols

Haplic Xerosols

3 4

r200

1100 2 2

:000*

o

Ro3ai

Rp Undulating to rolling high plateaux

2600r

NUMBER

FACET undulating plateaux2

rolling plateaux3

depressions with seasonaldrainage deficiencies

AR,-A 60 30 10

SLOPE (%) 2_8 8-16 0-2

SOIL

Eutric Nitosols Eutric Nltosols Chromic Vertisols

Rp4-v Dystric Nitosols Dystric Nitosols Dystric Glevsols

Rp Eutric Nitosols Chromic Luvisols Vertic

Roc Vertic Cambisols Futric Cambisols Chromic Vertisols(stony phase) (lithic phase)

Chromic Cambisols Eutric Cambisols Chromic Vertisols(lithic phase)

Roj - Undulating plateaux

NUMBER

FACET undulating plateauxAREA (q 70

SLOPE (5) 2-8SOIL

Rp; Chromic Luvisols(stony phase)

36

Krn

2

flat plateaux.Ju

Chromic Vertisols

NUMBER

FACET

AREA ()SLOPE (%)

SOIL4

Pv

37

undulating plateaux

40

2-8

Chromic Vertisols

m

7600r

2 2

depressions with seasonal

draihai3e defciencies40 20

0-2 Fi

Eutr-ic Fluvisols Dystric Nitosf3

4-38

- hilly terrain of raodarate to high relief with a substantial rWO ofmoder6tely sloping va)leys interspersed. thrbutfhout

NUMBER

FACET froderate to highrelief hills -

2

ror-i,rate to highreiiel hills

3

valleys

AREA 40 30 30

SLOPE ('2i) 30-50 16-"A 0-8

SOIL

Lithosois Cultic :egiosols Vortic Catf-bisols(fithic phase) (stogy phase)

2Rqv Orthic Acrisols Dystric Nitosgis Dystric Nitosols

Lithosols Lithosols Egtric Regosols. ,.s,i0ine H.:1,t..)

Orthic Acrisols Grtnic ,P,:i'sofs Dystric Nitosols

Lithosols Lithoscis fiE,h'ii.,: Xerosels

Litnosols Lithosols Chromi, Vertisois

Sq Lithosols Cambic- Areno5:ok Chr'orilic Cambisois(lithic phase)

R(12 Lithosols Lithosols Chromic Cambisols

Pp Lithosols Lithosols Entric Fluvisolt,

RS Lithosois Eutric CAmbiso'is Eutric Cambisols(lithic

I 7 f-K)

.0 Km

NUMBER i 2 3 4

FACET undulating plains, rolling plains hills inci.sed valleysAREA (%) 40 40 10 10

SLIPE (%) 2-8 3-16 16-30 30-50-i-

SOIL

Rrv

Luvic PhaeoLems Luvic Phaeozems Eutric Cambisols Lithosals

4-39

Gently sloping rises and low plateaux

(sodio ph3se) (sodic phase)

.04

Chromic Vertisols Chromic Luvisols Chromic Luvisols Lithos° s(stony phase)

4-40

Rs - Severely dissected sideslapes and piedmont zones

L.nrpit.oillca Sec lion

(stony pase)

Deeply incised valleys and valley bottoms are generally parallel to slhoe,thus do not shos, up on cross-section 1.

FACET

AREA ()SLOPE (t)

SOIL

v

- 2

deeply incised valleys rolling sideslopes40 30

30-50+ B-15

Lithosols Eutric Wtosols

Lithosois Niosols(lithic phase)

. idesiopes

20

16-30

Chromic Luvisols(stony phase)

Dystric Nitosols(lithic phase)

val ley bottoms

ID

0-2

Chromic Vertisols

Dystric Nitsels(stony phase)

Rs3v Lithosois Eutric Renosols Eutric Regosols vertic 00151)1 sois

(1{thlc phase) (lithi hase) (stony phase)

Rsv/s tithosols Eutric Nitosso'ls Chromic Lpvlsols Eutric Nitosols(stony phase)

Rs Lithosols Dystríc Nitosols Dystric Nitosols Dystric NitosoIs

Rs1 Lithosols Calcic Xerose)s Lithesols Calcaric Fluvisols

a, 2.rks Lithosols

(lithir ohase)Calcic Cambisols Calcic Cambisols Calceric Fluvisols(lithic phase) (lithic phase)

I Sc Lithosols Caftis Cambisols Calcic Cambisols Orthic Solohcheks(petrocaIcic pnsse) (lithic obase)

4Lithosois Chromic Cambisols Eutric Cambisols Eutric Fluvisols

(stony phase) (l(thic phase)

Rse Lithosols Gypsic Yermosols(saline phase)

Lithosols Orthic Solohch-,(petrogypsic phase

Rsi Lithosols Eutric Cambisols Eutric Cambisols Gievic Cambisels(stony phase) (lithic phase)

b,2"m Lithosols Eutric Cambisols Lithosls Gleyic Ca*lsolk

NUMBER 2 4

lt - Moderately dissected sdesiopes and piedmont zones

2.000F

*50

1900r

MOO

Cit0

210C,7

2000-

[900 r,

4 1

Lancpiudir,;:i Sti;iGn

Incised valleys are generally parallel to s o, thus do notshow up on the lon9itudinal cross- section

, incised valleys do not occur in ohit Rt'' and hills isake un20% of the unit

Seclion

4

i n Km

NUMBER 1 2 3 4*FACET undulating sidesinpes rolling sideslopes hil)s incised valleys

AREA (. )

SLOPE (44)

SOIL

40 40 10 10

2-8 8_15 16-30 30-50+

Chromic Vertisols Eutrir Nitosola Chromic Luvisols Lithosels,5,.i.

VDystric Nitosols Dystric Nitosols Orthic Acrisois Lithosois

n't Chromic Vertisols Eutric Nitosois Orthic Luvisols Lithosols(stony phase)

Eutrio Cambisols Eutrio Regosois Ehtric Regosols Lithosols.(stony phase) (lithic phase) (lithic phase)

Eutric Reoosols Eutric Reqesols Litbosols Litraosols(litnic phase) (Iithic s)tiase)

7

Eutric Nitosols ChroN6c 'tuviscfla Chromlc LuvISGiS Lithosols

a(stony phase)

Re'9

Oystric Nitosois Dystric Nitesol4 Orthic Acrisois Lithosols

Rt3 Eutric Nitosols Chromic Luvisela Chromic Lbvisels Lithosols

Chromic Cambisois Chromic Oamo/sols Lithosols Lithosols(stony phase)

Calcio Xerosols Cado Xeroa..ls Lithosols Lithosols(lithic por::)

Euio ic Cambisols Calcio Caa:: -." Caicic Cambisols Ltthosols(lithic tiiasel (lithic phase)

kt,

,4Rt_

Eutric Regosols

ikiplic Phaeozen6

Calcic Camoisols(lith¡r phase)utEric eambisols

Lithosols

Eutric Cambi sols Lith sois(stony phase) (lithic phase).

Rt4cfg tiaplic Phaeozems Haptic Pht Eutric Carablsois tithosols

(stony ptolse) (lithic phase)

Rt' Eutric Regosols Calcio Xerosols Lithosols Lithosois(lithic phase)

Chromic Cambisols Chromic Cambisols Cambic Arehosols Lithosols(lithic phase) (lithic phase)

3RC: Cambic Arenosols eambic Arrasols Lithosols Lithosels

(lithic phase)

Rts. Olromic Cambisols Eutric C,rabisols Eutrio Camktsois it tiles:cis(lichiic (lithir phase)

Orthic Solonchaks Gypsic Yermasols Lida:76°1s Lithosols(poi- togypsic phase) (saline phase)

Ru - Flat to undulating lowland piains and low piatea

aso F

1050

PA?

4

1000 r

4-42

Cambio Arenosols

Chromic Vertisols

Gypsic Yermasois(salina phase)

Eutric Nitosols

Chromic Lusmisels

Eutric Nitesols

Chromic Luvisols

Ve-tic Cambisois

Chromic Vertisols

Orthic Solonchak(petrogypsic phase)

Chromic Vertisols

Chromic VertiRols

Chromic Vertisols

Chromic. Vartisols

K

NUMBER 1 2

FACET undulating plains flat plainsARPA (iI) /0 30

SLOPE (5) 2-8 0-2

SOIL

Ruv Dystric Nitosals Chromic Vertisels

Ru/g Chromic Cambisols Chromic fambisalsv

Ru1 Haplic Xerosols Haplic Xeroseis9

Rug

2 Dvstric Nitosols Dystric Mitosols

Ru- Eutric Nitosols Eutric Nitosals. g

Ru4 Chromic Cambisois Chromic Cambismais9

Ru1 Calcio Xerosols Calcic Xeresol4C

2

RucChromic Vertisols Chromic Vertiscls

3

RucEutric Cambisols Chromic Vertiscls

R4 Chromic Cambisois Chromic Cambisols

Rur., Calcio Xerosois Calcio Xerosols(petrocalcic phase) (petrocalcic phase)

litf" Calcic Cambisols Va,-tic Camhisols(petrocalcic phase) (patrocalcic.phase)

4-43

- Rolling to hilly plateaux

SEAL

Rwl Dystric Nitosols Dystric Nitosols Dystric GleysolsV

Rw'y Chromic Luvisols(stony phase)

Chromic Luvisols(stony phase)

Chromic Vertisols

3

RwvEutric Nitosols Ewtric Nitosols Chromic Vertisols

Rw Eutric Cambisols Eutri- Pegosols Chromic Vertisols(stony phase) (lithic pace)

Rw ' Chromic Luvisols Chromic Luvisols Vertic Lovisols9

2Rw Dystric Nitosols Orthic Acrisols Dystric Meysols

9

Rw3 Chromic Luvisols. Chromic Luvisols Vertic Lovisols9

Eutric Cambisols Lithosols Gleyic Cambisols9 (lithic phase)

Rw Eutric Cambisols Eutric Cambisols Chromic Vertisols(lithic phase) (lithic phas)

Rw2 Haplic Phaeozems Haplic Phaeozems Chromic Vertisols(lithic phase)

Rw Eutric Cambisols Cambic Arenosols Gleyc Camhisolss (lithic phase) (lithic phase)

Chromic Luvisols Lichosols Eutric GleysoIsIn

OK N

NUMBER 1 3

FACET culling plateaux hilly plateaux depressions with seasonaldrainage deficiencies

AREA (fl 70 29 10

SLOPE (Z) 8-16 16-30 0-2

Severely Ossep ed plateaux wlth mouera,,t hiRx4, 4,

2300

2200

2!00 r

2000 L

NUMBER 1

FACET steep sideslopesAREA (%) '50

SLOPE 3,0-50

SOIL

Rx Chromic Cambisols(lithic, phase)

4-44

RxeLi thoSol s Rendzinas

2

plateau remnants

40

2.H3.

Chrrc Luvis isphase)

(11 thic phase)

2 2

m

2400rI

:

:

2200LRg

1 2000-

V,I

ri$00

Ry

Ry

V

Ry4+

Ry;

V S

Rym

4-45

Ry Undulating high plateaux with a substantial proportionof hills interspersed throughout

15 Km

NUMBER

FACET undulating moderate relief hillsAREA (%) 60 40

SLOPE (%) 2-8 16-30

SOIL41 Dystric Nitosols Dystric Nitosols

Eutric Cambicols Eutric Regosols(stony phase) (lithic phase)

Chromic Luvisols Chromic Luvisols(stony phase) (stony phase)

Eutric CamOisols Lithos(stony phase)

Eutric Nitosols Chromic Luvisols

Vertic Luvisols Chromic Luvisols

Eutric Cambisols Lithosols(stony phase)

Chromic Luvisols Eutric Cambisols(lithic phase)

4In Ryv volcanic plugs instead of moderate relief hills

4-46

- Structural river gorges

.20

NUMBER . 2 3 4

FACET steep sideslopes v,-sry steep sideslopesand fault scarps

moderate sideslopes gorge's hntl,,og

AREA (;) 50 20 20 10

SLOPE p) 16-30 30-50+ 8-16 2-a

SOIL

Sgc Litnosols Lithosols Cambisols Eutric FluvisoIs(lithic phase)

Sgm Eutric Cambiwls Lithosols EutrIc Ca)Ibisols Evtric(lithic phase) (lithic phase)

66oe

p 1:

RIs

mis

;ooe

s ah

o m

c6jo

tote

.ea

chpe

rcor

t in

RH

10 X

m

NU

MB

ER

'

12

35

oF

AC

ET

very

ste

ep s

idos

lope

sof

par

alle

l rid

ges

stee

p si

des3

opes

mod

erat

e si

des1

opes

plA

teau

terr

aces

and

gent

le s

ides

lope

sin

ter-

mon

tane

val

leys

esca

rpm

ents

AR

EA

50JO

n 10

1010

It)S

LOP

E (

X)

SO

IL

30-5

0+16

-30

8-16

2-8

0-8

SO

)-

1

Shv

Chr

omic

Cal

libis

ols

Chromic Luvisols

Chr

omic

Luv

isol

sEutric Nitosois

Chr

omic

Vor

tisol

5R

ock

curi

oso

(lith

ic p

ace)

Lith

osol

sLi

thos

ols

Eot

ric C

ambi

sols

Roc

k su

rfac

eSi

dD

ystr

ic C

ambi

sols

(Iith

ic p

hase

)D

ystr

ic C

ambi

sois

(1ith

ic p

hase

)O

thic

Acr

isoi

s(s

tony

pha

se)

DystrIc Nitosols

(sto

ny p

hase

)D

ystr

ic N

itoso

lsR

ock

6urf

ac,i.

i

Sh4

Lith

osol

sE

utric

Rey

osol

s(li

thic

pha

se)

Eut

ric

Cam

biso

is(li

thc

phas

e).E

utric

Cam

biso

ls(li

thic

pha

se)

Eut

ric C

ambi

scls

(sto

ny p

hase

)R

ock

surF

ace

Shl

Dys

tric

Cam

biso

ls(li

tnic

pha

se)

Ort

hic

Acr

isol

s(s

tony

pha

se)

Dys

tric

Nito

sols

Dys

tric

Nito

sols

Oys

tric

Nito

sols

Roc

k su

rfac

e

5h2y

Chr

omic

Cam

biso

ls(li

thic

pha

se)

Chr

omic

Luv

isol

s(s

tony

pha

se)

Chr

omic

Luv

isol

sE

utric

Nito

sols

Ver

tic L

pvis

ols

Roc

k su

rfac

e1

Sh' 9

Rock surface

Lithosols

Lith

osol

sE

utric

Reg

osol

sH

aplic

Xer

osol

sR

ock

surf

ace

(lith

ic p

hase

)(s

tony

pha

se)

Shc

/gLi

thos

ols

Eut

ric C

ambi

sols

(lith

ic p

hase

)H

aplic

Rha

eoze

ms

(sto

ny p

hase

)H

aplic

Pha

eoze

ms

Chr

omic

Ver

tisoi

sR

ock

surf

ace

qi - m

Lith

osol

sLi

thos

ols

Ent

ric C

ambi

scls

Eut

ric C

ambj

!i;oi

sE

utri

c Fi

ovis

ols

Roc

ksu

rfac

e,(li

thic

pha

se)

(sto

ny p

hase

)S

h,

mig

Lith

osoi

sLi

thos

ois

Hap

'lic

Xer

osol

s(li

thic

pha

se)

Hap

lic X

eros

ols

(sto

ny p

hase

)H

eplic

Xer

osol

s(s

tony

pha

se)

Roc

k si

JI,l'

ace

In

2200

2100

2000

19

4-48

Sk - Hill and valley landforms of lowresulting from fold structures

3 Krn

NUMBER 1

FACET low parallel broad undulatinqrolling hillsAREA (%) 60 40

SLOPE (%) 8-16

SOIL

Sk Eutric Cambisols Vertic Cambisols

valleys

rnate relief

Low to moderate relief parallel ridge and valley topo api, associatedwith extensive fault sets.

1800,-

1700

NUMEER

FACET sideslopeS

AREA 60

SLOPE (%) 8-16

SOIL

to. tc+r

Eutric Cambisois(stony phase)

Dystric Nitosols

Orthic Soloncaks

Eutric mbisols(stony phase)

Eeric Cambisols

Eutric Ni osois

Eutric Cambisols Eutric Cambisols Eutric Cawhisols Orthic Luvisels(lithic ohaSe) (lithic phase)

2 4

Ilel valleys steep sidesiopes plateau terraces andgentle side.slopes

20 10 10

0-8 16-30 2-8

Eutric Regosols Eutric Cambisols Lithosols(lithic phase) (stony phase)

Dystric Nitosols Dysteic Nitosols Orthic Acrisols

Lithosols Orthic Solonchs Lithoscls

Eutric Cbisols Eutric Combisols Lithosols(lithic phase) (stony phase)

Re.odzinas Eutric Camhisols(lithic phase) (stony phase)

Zutric Nitosols Chromic Vertisols Chrop,,ic Lovisols'

Sin - Moderate to high relief parallel ridge and va ley topography

associated with extensive fault sets

very steep siOeslopes

U. ,EA (b; "30

;10PE (%) 30-50

i,.07L

steep sideslopes

20

16-30

moderate sides1Dpes

20

3-16

small parallel valleys

20

0-6

plateau terra,gentle sides:

10

2-8

Eutric Cambisols Orthic Luvisols Orthic Luvisois Eutric Nitosols Eutric Nitcsolu(lithic phase) (stony phase) (stony phase) (stony phase) (stony phase)

,.v. Lithosols Eutric Regosols Eutrlc Cambisols Eutric Cambitols Eutric Camhisols

, (lithic ;:nase) (lithic phase) (stony phase) (lithic phase)

vLithosols Lithosols iihcsuls Orthic Sonlohchaks

(stony phase)

Eutric Regaseis(lithic phase)

Orthic Acrisols Orthic Acrisols Dysti-ic Nitoscls Dystric liitosoIs Oystric Nitosois-..,

,r,-g

(stony phase)

Lithosols Eutric Cambisols(lithic phase)

Eptric Cambisols Vertic Cam isols Eutric Cambiscis

Lithosols Lithosols Eutric Cambisols- Eutric Fluvisols Eutric Cambiso,s(li'thic phase) (stony phase) (lithic

, LiLaosols Lithosols Lithosols Calcaric huvisols Caicic Xe.(stony phase)

Lithcsols Eutric Cambisols Eutric Cambisois Eutric Cambisols Orth'ic Luvin,sis(lithic phase) (lithic phase)

. 2AF

ITSLithosols Lithosols ,Haplic Xerosols Haplic Xerosols Haplic 'Aerosols

(ithic phase) (stony phase) (stony phase)

im'

Lithosols Eutric Cambisols Eutric Cambisols Eutric Cambisols Orthic Luvishl(lithic phase) (lithic phase)

Lithosols Lithosols Haplic Xerosols Haplic Xerospis Haplic Xenosos(lithic phase) (stony phase) (stony phase

JER 2 3 4 5

2000

500

4-51

S- - Step faulted plateaux of the Ethiopian rift margin

NUMBER

FflET plateaux fault scarps horst crests(%) 70/50 20/30 10/20

SLOPE (%) 2-8 50+ 2-8SOIL

Vertic Cambisols Rock surface Eatric Cambisols(s ony phase)

Vertic Cambisolq Rock Surface Eutric Cambisols(stony phase) (stony phase

4-52

Sc - Linear ridges with wide intervenina parallel valleys

2200- 3 3 3 3

I

2 2 1

1800,-1

IO Km

NUMBER 1 L 3

FACET ridge sideslopes bread parallel valleys crestsAREA (%) 50 30 20

SLOPE (%) 16-30 0-8 8-16

SOIL

Sq Chromic Luvisols Pellic Vertisols Eutric Nitosols

NUM3ER 1

53

Ss - Step faulted plain and low plateau complee of the Ethiopian rift withnumberous fault scarps, sags and asseciated vents, craters and other volcanic remnants

1400 -

35 Kra

2 3

FACET undulating plains caldera rims and fault scarps

and caldera floors volcanic cones and plugs and very steepsideslopes

30 20

16-30 30-504

Eturic Cambisols Lithosols(lithic phase)

4

permanent marsh

10

0-2

-

n,a MaliiC

AREA(%) 30

SLOPE 2-8

SOIL

SsvMollic Andosols

.=or

50

Stclic r;17.

Generd Fatcon

st

-lating pl&teaux rol7in

Kfl

ttm

6

stc,

3

,

&hd

sidesY',,pes

16-30

ChroAc LNv'sols(stony F.i3O

Eutric s(lithic

Luvisols Luvisels Chm.

St - tt rlver

Su - intensively faulted lava platforms of the Af.,1- lowland

ro,

-5.5

500

6 K

NUMBER 1 2 3 4

FACET benches and valleybottoms

Moderate slopes steep slopes very steep slopesand fault scarps

AREA (t) 40 20 20 20

SLOPE 0) 2-8 8-16 16-30 30-50+SOIL

Sul Eutric Cambisols Eutrir IMmbisols Lithosols Rock outcrop(stony phase) (lithic phase) Lithosols Rock outcrop

2

Suv Orthic Solonchaks Lithosols

4-56

Sx Severely dissected rift margins ci fault

20 Km

NUMBER 1 2

FACET steep cut stream channels plateau r Anants

and escarpments

AREA (%) 60 40

SLOPE(%) 50+ 8-16

SOIL

Lithosols Eutric Cambisols

2-a..",

Sy Intensively faulted lava fields and platforms of'the Afar lowlands-characterized by long linear fault scarps numberous plateaux horstsand associated grabens fflied with ailuvumcoilvium and evaporitedeposits.

rn

600

4-57

K m

NUTR 1 2 3

FACET lava platforms andhorst crests

grabens fault scarps

AREA (%) 60 30 10

SLOPE (%) 2-8 3ro,

SOIL

SYvLithosois Orthic Soionchaks

(petrogypsic phaseR ut v,

vo canoes of dramatic mountain6us relief

rn

4 ICO

4 -

39001-

4-58

Afro-alpine plateau summits associated with extinct central

7 t<

NUMBER

FACET rolling slopes undulating slopes alpine boosAREA (%) 50 40 10

SLOPE (S) 8-16 2-8 0-2

SOIL

Va' Eutric Cambisols Lutric Cambisols Dys ,ic Histosols

5-191

5.16 YERMOSOLS

5.16.1 FAO classificationYermosols are soils occuring under. an aridic moisture regime;having a very weak ochric A horizon and one or more of thef011owing;'a cambie .15 horizon, an argillic 13 horizon, agypsic horizon; lac:King other diagnostic characteristics whichare diagnostic for Vertisols, lacking high salinity; lackingpermafrost within 200 cm of the surface.

IlL_E_Ip14.ç_Iermosols are Yermosols haviniz no diagnostic horizonsother than a very wea k A horizon and a cambic B horizon; lackingtakyric features.

Calce Yermosols are Yermosols havizc. o. calcic horizon within125 cm of the surface (the depth uzrement varies with theweighted average of the textural clas&) lackina an argillic Bhorizon overlying the calda horizon; lacking takyric features.

w§ic. Yermosos are Yermosols having a gypsic horizon withincm of the surface (the depth requirement varies with the

weighted average of the textural class); laChing an argillic Bhorizon overlying the gypsic horizon; lae7:15 takyric features.

Luvic Yermospis are Yermosols having ah argillic B horizon; acalce or a gypsic horizon may be present if uhderlyino thehorizon, lacking takyric features.

Takyric Yermosols are Yermosols showing takyric features.

5.16.2 General environmentYermosols cover approximately 3% of Ethiopia, and are

thought to occur almost exclusively on the evaporite landforrhsof southern Harerge and southern Bale. They occur on theflatter land, giving way to Lithosols as slope angles increase.

Yermosols are oss Jially a more version ofXerosols and should occn n desert, as ouposed to ard andsemi-arid environments. The d-istinction is ou u the

very weak ochric J orizon of thE: former a-h: o:-, zifak cohric

A horizon of the as foH..:

5.16.4

A very weak ochric A horizon has a very 1 - c,_)ntent of oraanicmatter with a weighted average percentage of less than 1 percentin the surface 40 cm if the weighted averse sana/clay ratio forthis depth is 1 or less; or less than 0.5 percent organic matterif the weighted sand/clay ratio is 13 or more; for intermeaiatesand/clay ratio is 1; or more; for intermediate sand/clay ratiosthe organic matter content is intermediate. 'When hard rock, apetrocalcic horizon, a petrogypsic horizon or a duripan occurbetween 18 and 40 cm, the contents of organic matter mentionedabove are respective1y less than 1.2 and 0.6 percent in thesurface 18 cm of the soil.

A weak ochric A horizon has a con of organic matter Whichis intermediate between that oi ..ery weak. ochric A horizonand that required for the moilic A -o.orizon.

Becai

distinctionOT Ethiopi,Geomorp

evidence that. on200 mm annually or1,71 (see section

:ological env-,tion Is particu

Lan

ac=ate laboratory data is required tiisuch 5 :it avssi7 'le fon i

risticsSimilar to Xerosols, Yermosols '

weak structur, high pH, organicCaCO3 and C,a1 . As A. csoc Occur

are less civi.iodlly ver H. than thevery freque,

and Xros.i)ls on therather an'o ry,

in rainfall A-mes of uidi-ns of the f horiLou can reach

ass Iandforms

Tow ra n'ss where

sparse -niz largely due tu

medium r ioarse texture,und lations of

eviidorites, theyof Ethiopia, and are

e and natura ,ionYermosols in Ethinoia are e=.,st exclusively ,nd,iio ,soattered

natural vegets* - For c livestock graig

Of the five types of Yermosols defined above, it is notimpossible that all occur in Ethiopia. However, Gypsic Yermosols,

very frequently with saline, lithic and petrogypsic phases, are themost common.

5J6.f Profile descriptions

5.16.7.1 Gypsic Yermosol phase), lower Wabi S_hebele

This soil 005 association with the Lithosol describedin section 5.3. Si an.;..i in association with the Solonchaks of thealluvial and colluvial slopes and of the undulating land on largelyevaporite deposits in the -3puthern

This soil is !,-1 1 n the two, neither as shallowas the Lithosols of the nor as saline as the Solonchaks

of the flattest land.Not only low rainfall, but also surface salinity which

reduces vegetative cover to a minimwr: is responsible for the veryweak ochric A horizon.

Source: WABI SHEB

Lithic Soils with diffuse calcium sulphate on shallow slab derived

from the main gypsum P.DrIE8;t17.011-

General

See section i. 3,

5-193

5.16.5 Management

Yermosols suffer the potential limits to agriculture ofXerosols, however these limits tend to Goo:Jr more frequently and themore extreme. Petrogypsic horizbns, shAlo 6epths, salinity,coarse textures and/or very low organic matter contents are almostuniversal in Yermosols in Ethiopia.

Occurence

B) Profile description

0-20 cm

20-50 cm

5-194

50+ cç R Gypsum slab in situ.

The upper horizon therefore consists of a regular gylasum powder restingon the gypsum slab. Disaggregation and exfoliation in situ of thegypsum slab may be observed and this is manifest in horizOn AiR in theprofile described. Part of this gypsum is solubilized by rain waterand accumulated in water spreading zones on colluvial or alluvialdeposits located in a lower position and it provides soils with crusts,but on the hills, there is no neocrysta:ion of gy.bsum. Thesesoils are classed among soils with powder lime'since they containfrom 10 to 20 percent carbonate.

; Physical and chemical characeristics

See section 5.3.5.1

D) Cultural and pastoral fitness

See section 5.3.5.1

,td Yellovish white (5 Y8/3); loam; singlegrained structure; very powdery and

friable; some rootlets; short anduniform transition to:

AIR Yellowish white 5 Y 8/3); loam coatinggypsum elements; not very hara, tending

to -j.powdery; very few rootlets; suddentransition to

5-195

5.17 NITOSOLS

5.12.1 FAO classification

.N:i.tosols are soils havidog an arillic E horizon with a claydistribution. w'nere the percente of clay does not decreasefrom its maximum amount by as much as 20 7percert within 150cm of the surface; lacking a wit:lie A horizon; lacking as albicE horizon; lacking tbe tonelg ,dhich is diagnostic for thePodzoluvisols; lackiLg ferric and vert orope-rties;ol:',nthlt;-., within 1fb cm of t.ne surface; laclr.ing at aridicmoisture regime.

Futric Nitosols are Ditosols havinc- P 1""I'" saturation, rfpercent or more 'G.;; throu.ghout the argillic B 'horizon;,lithn 125 cm of the nrface.

Dvstric Nitosols are Jitosols hav±iF a base satu-tion ofless than 50 percent (b-y TAI,Chc) i n at 72east a ba.rt of the

horizor within 15 cm of t-he ..7:,,-urfac; lacking ahigh orgahic nìa.tter conte,.nt in the P. norlzon and lacking, anuff.pric A horizon.

roxmc Nitosols are il-;.osols having a 1;:a.-.1).ration of lesstheo 50 'oercer_t (by tEcOAc) in at least a part of tne argillicB horizon within 125 c;i-of the surface; having ar umbricA horizon or a high or YL(.; matter content in tire B hor:Izon,or both.

5.17.2 General environmantNitosols are found in Ethiop-ia in the highlands and in

the western lowlands. They develop on a wide rancie of parentmaterials:volcanics, metamorphics, granites and felsic materials,sandstones and limestones.

Nitosols.occur on the gently sloping to steep lana, thefiat land being mOstly with Vertisols or Gleysols, the stpeperslopes having more ,;hallow sci is Acrisols/luvisols and

Cambisols. Nitosols make un 12 percent of the soils of Ethiopia.

5.17.3 CharacteristicsNitosols are clayey, reddish brown to red soils with

an areillic B horizon, without abrupt textural changes.The soils are deep, have a stable angular to subangularblocky structure, shiny ped surfaces and are very porous.They have a high moisture storage capacity and a deep rootingvolume. The clav is mainly kaolinitic, but therP are stillsome weatherable minerals in the soil.

Dystric and Humid Nitosols have a low base saturation,the latter having a high organic matter content in the Aand/or B horion. Putric Nito?ols havP a high base saturation:

5.17.4 Land use and natural ve PtationIn areas with a moderate to high pcoulation

Nitosols are intensely cultivated for annual as well as forperennial crops. Around jima and in the Chercher highlandsthese soils are used for ocffee growing.

In the west of Ethiopia, with a low popPlation density,these soils are mainly under natural vegetation. This can beforest, tree savanna or open savanna, dependin on the amountof precl.,itation and..............influence

5.17.5 ManagPment

Nitosols have very good potential for agriculture.Physically they are porous, well drained, have a stablestructure and a high water storage capacity. Workabilitydoes not create problems: even snortly after precip-itationor in thP dry season land can be prepared wjthout great ciff-iculty.

Chemically these soils have a rather low CEO for theirclay content and available phosphorus are very low.

Dystric and Humic Nitosols are excellent coffee growinsoils, although fertilizers have to be applied.

5.17,6 Occurence_All the above mentioned Nitosols occur in Ethiopia.

Eutric Nitosols mainly occur in the central and easternhighlands; Dystric and Humic Nitoapls occur in areas withhigh precipitation, the latter mainly under natural vecietationin the lowlands and in the highlands.

5,17,7 Profile descriptions

5.17.7.1 Humic Nitosol, ¡lakeThese soils haino a relativPly light textured topsoil

almost classify. as' Acrisols. Due to this rather lighttexture, these soils are very erodable; also land preparationcan cause compaction of the topsoil.

Source: LUPRD

-A) Profile description

- Information on ti-le site:

Profile no: PI, ---3ako

Classification: UUE1.0 NitosolAuthors:Location: 3 km NW of AraloElevat'ion: 188e niPhysic-x.riphic

110-190 cm Reddish brow, (2.5 YR 4/5 moist);clay; weak medium sub-angular blocky;friable moist, non-plastic, ron-stickywet; many micro, many very fine, commonfine pores; few fine grass roots.

5.17.7.2 Eutrio Nitosol, FlararThese soils are developed on the slopes ano coiluvIcAl

slopes of the hilly landscape around Hacer. Te convex valleysare mostly in Vertic luv-kols (5.19,7,3) and the steep sloesin Chrornic Luvisols (5.19.7.4 )

Laboratory data

Textu,-4, (%, mm),..--u,..,_

0.2-0.05c.0.5-0.0020.002

0-20

,-.'o

11153)

20-60

6

5

3060

De7Dth HT)

60-110

1015

110-150

1-", 1..,...L

PH,--

i..i-S h.6

KC1 ',0 --?..,,' 2:-.1 1.2CaCO (5)Exchangeabi cation3

(meg/100g)Na LT ,,-.,'-', n..9 2.7K D.5 ,:.5 u.) 0.5Mg _LA --..

,6

Ca :' ..-, ;. 1Al+H .2:1.1'; i,,.2,8 21.1 l',.4i.';Mn 0.,,D3 (LOS u..1._:,,, 0.14Sum 15.2 1:?.1. 11.L 9.2

\CEO (me/100 g) 52.1 51.0 36.2 1-11.0

Base saturation r'n 29 29 30 20Organic C (n 1.7 . ^ 1;2: 09Total N 1) 0...1 ,. 0.15 0.0:CiN ,'-, '' 8 11Available P,D0,..(11-5.m':Ava ilable K-(3pM)

:101'000

6

1000i,

10002

1500

Surrounding country:MicrotoTpography:Slope:

Vegetation:

Land 'ase:

Climate:

- information on tne soil:Parent material:Run off:

Permeabil-7tv;

Internal drainage:Depth of ground water:Moisture condition:Stoniness and rock-

outcrop:

20-40 cm

40-110 cm

dissected paateaugullies

conve:o YR expobuitAcacia; Croton MacrostacIrr

Erythrina Abyssinica; Ficusintensive cultivationhumid temperate

basaltmediummoderatemediumnot encounteredmoist throughout

none

- Profile description:

Deep brown to red soil at the ulDper horizon and reddish brown atthe lower horizons; abundant nedium sized roots in the upperhorizons.

DE,rk redish brown (5 YR 313 moist);clay; weak fine sub-angular blocky;friable moist, slightly sticky, non-plastic wet; many micro, many veryfine, few medium 'pores; many mediumsized grass roots; gradual, smoothboundary.

Dusky red (2.5 YR 3/2 moist); clay; weakmedium sub-angular blocky; friable Inoist,non-plastic, non-sticky wet; many micro,many very fine, few medium no res; manyfine and very fine grass roots; clearwavy bo,Indary.

Dark red (25 YR 3/6 moist); clay; weakmedium Torismatic structure; friablemoist, slightly sticky, non-aasticwet; many micro, many very fine, fewfine pores; common fine grass roots;clear, wavy boundary.

Surrounding country:.Microtopography;Slope:Vegetation:

T.,and use

20-40 pm

u-liA) cm

5-200

dissected Plateau

7%, convex, VE exposureAcacia; CToton Macrostachys;Erythrina Abyssinica; Ficusintensioe -cuitivatIonhumid temperate

Laruv ref'!. (2.5 YR 3/2 moist); clay; weakm.,eJium sub--angular blocky; friable moist,non-plastic, non-sticky wet; many micro,nieny very fine, few median: pores; manyfine and very fine grass roots; clearw,371y boundary.

Dark red (2.5 YR moist); clay; weakmedium orismatic stractnre; friablemoist, slightly sticky. non-plasticwet; many micro, many very fine, fewfine nones; common fine grss roots;clear, wavy bouhdhry.

- information on the soil:Parent material: tasadtRun off: mediamPermeability: moderateInternaa. drainage: mediumnepth of ground water not encounteredMoisture condition; moist throughoutStoniness and rock-

outcrop: none

- Profile description:Deep brown to red soil at the upper horizon and reddish tTC,ViTi at

the lower horitons; abundant medium sized rocen in the upperhorizons.

-2a,trk reddish brown (5 YR '';.1".3 moist);

clay; 1... rinr, sub-angular blocky;friahlr hoist, slightly sticky, non-plastic dot, Irg-;:.-ny micro, nana veryfine, tau medival pores; many slediumsized gras rooth; smoothboundary.

r,-201

The colluvial deposits are complex and includeweathering material derived from limestone hills, some sand-stone and granite.

Source: WABI S'

Ai Profile descriction

Leavinz Harar to the North, on a- natunll section due toweathering the following profile may be observed uhder agraminea cover:

0-.50 cm

50-47o CM

Dark reddish-bro,wn (2.5 YR 3/4); clay;very well-developed crumb to granezIrstructure;

Dark. red (10 YR 3/3); cIiy; small norizontaland vertical cracks delimiting shiningprisms; the latter are very friable andprovide material with. a ve,-y w,.-11-developedmediam angular blocky stru.cture includingshining aggregates; friable.

470-800 cm Reddish-brown weathered sandstone.

This soil is dark reddish brown at the surface and. dark redat depth and has a cla-ey texture, It is very thick with agranular structure in the topsoil turning into a very well-developed medium angular blocky structure at deth- The wholeProfile is very friable.

In the Alemaya and Mc.-:'.e-regions, the upper horizon is brownto dark. brow:. This is not due to a Ffreater content of organicmatter, but to'the presence, higher up, of limestone remnantsproviding brown .;,;,.;:hered material overlaying tlAe slopes in theform of colluvial deposits, In the upper part of the hills theweatherina of limestone produces 77a-.Lcaric PhaeozeYrs (5.14.7.4)and. Renci,nas j..1 ).

B) Laboratory data

The soil is not calcareous. The organic matter content is mediumdown to 50 cm. depth. C/N is low and characterises a soonmineralized humus, The total N/Total 2,)05 ratio is approximately2 and reveals a nutrion.al unbalance detliimental to nitrogen.

Cultural fitness

These soils are largely crcl,Dped mainly to maize, sorghum andchatt (Catha edulis)which is a "cash-crop". Beans, aweetpotatoes and various other vegetables (potatoes, onions, tomatoes)are also produced in large quantities.

The fert4lity level of these soils is medium as regards phosphorusand potash but is very poor as reg,:ards nitroen.

Consequently, it is necessary to add nitrw,:en carriers in orderto increase in a considerable pro7.-)ortion the yield of chattplantations and of annual crops.

Besides, since the contents of phosphorus and potash are medium,adding phosphate and potassium carriers seems advi sable if theeconomic conditions of cultivation. make it possible.

The most urgent measure to be taken is erosion control. All theHarar region is .afscted. by a very serious headwater erosionresulting in the formation of very deeply eroded gullies, andvery often of "lavakas" 3 to 5 m deep quickly goiniT, up thehillslopes.

Textu.K.e

CaCO,_,.

Organic matter (%)

0-50

C

0

2.7

Depth (rq11)

50-170

C

0, ,,-)._.-73

970+

C

0Cl

Total N W 0.12 In mC/N 12 'CI mpfi I .. 6.7 6.5Exchangeable cations

(me ¡100g

Ca 16.6 10.0 mMfiz 9.3 7.6 mK 0.3 0,2 31'

Na 0.1 0.1 In

Sum 26,3. 17.9 rd

CEC (me/100g) 26.3 17.9_ Ill

Base saturation (%) 100 100 Ill

Total P,-,.0 (-,v,--n)( 5 , 500 400 400

ACRISOL

6.18.1 FAO classificat-ionAcrisols are soils having an argillic B horion with abase saturationof less than .50 percent..AIT PH4QACY at leastin the ldWer -Part of the B horizon within 125 cm of thesurface; lacking a mollic A horizon; lLcking an aibie Ehorizon overlying a slowly permeable horizon, the distribu-tion Pattern of the clay ant'', the tonguilig which are diagnosticfor Planosols, Nitosols and ree,-oectiVei,lacking an aridic moisture.. regias,

Orthic Acrisole are Acrisole having an ochric A horizon;lacking ferric propefties; lacking a hign oranic mattercontent in the f bori'Lol:; lacaing plinthi7:e within i25 rn ofthe surface; lacking hydromorphic properties within 50 cm ofthe surface.

Ferric Acrisole are Acrisole having a ochric A horizon;showing ferric properties; larking a high organic matter contentin the B. hori,zon; lac'Ang -p...i.inthite within 125 Cm of the surface;

lacking hydromorphic properties )..rithill 50. cm of -.t:,17:.e surface.

Humic Acrisole are Acrisols having an umbric A horizon or ahigh organic matter content in the B horizon, or both; lackingplinthite within 125 cm of the surfaee; lacking hydromorphicproperties vithin 50 cm of the surface.

Plinthic Acrisols are Aorisols having ialinthite within125 cm of the surface.

Cdeyic Acrisole are Acrisole showing '.rydromorphic Propertieswithin 50 cm of the surface; lacking p7inthite within 125cm of the surface.

5.18,2 General environment

Acrisols mainly occur in the high rainfall areas,associated with Dystric Nitosols and Dystric Cambisols.They are found on moderate to steep slopes,

5.18.3 CharacteristicsAcrisols have a distinct argillic B horizon and a

base saturation of less than 50 percent. They have a reddishbrown to red colour and a well developed structure. pH is low.Acrisols are very porous.

5.18.4 Land use and natural vegetationAcrisols are moderately suited for agriculture.Par

they are cultivated, partly they are left under naturalvegetation for grazing purposes.

5.18.5 Management

Acrisols have good physical characteristics. They

have a well developed structure and are porous. When they

have a light textured topsoil, problems due to cultivationmay arise as compaction and erosion increase under intensive use.

Chemically Acrisols are poor soils. CEC is low, base

saturation is low, pH is low and available phosphorus contentsare very low. Ilumic Acrisols, mainly occuring in the high-lands have a somewhat better chemical behaviour.

5.18.6 Occurence

Humic Acrisos are dominantly found in the highlands,Orthic Acrisols occur elsewhere. Ferric, Plinthic andGleyic Acrisols are not reported to occur in Ethiopia.

.7 Profile description

5.18.7.1 Humic Acrisol, AnnoThis profile is taken from the western highlands.

Although the topsoil is not very light in texture and thearea not very sloping, gullies are developing.

Source: LUPRD

Profile descriTytion

Information on the site:Profile no.:Authors:

Classification FAO:USEA:

Location:Eevation:Physiographic position:Land form:Microtopograp)hy:

Slope:Land use:

Climate:

Information on-the soil:Parent material:Drainage: '-

Depth of groundwater:Moisture condition:

Stoniness:Rockiness:Erosion:

Profile description:Uniformly dark reddish brown to dusky red clay profile

with well developed fine structures and porous,

0-15 cm

5-205

4 ..),erting and Fikru20/5/81Humic AcrisolUdic Rhodustalf

A.,:01 dno town1 850 mlower quarter of slopedissected plateausummit area of the ridge,strong gully development7-10%, convex, S exposure)0-60% cultivated, 40-50%left for grazing under treeshumid temperate

basaltwell drainednot encounteredthe upper 0-45 cm is moist,45-105 cm, is dry, slightly moistbelownone to slightly stonynoneSlig4t Sheet wash on slope,moderate g-1-y on ridge top

Dusk red (2.5 YR 3/2 moist);clay; strongly.. developed, very fine,F:,-:;'anolar aggregates; slightly haxd .

,aLy, friable moist, sticky non-Dlastic

.- many micro, many very fine,Hmany

-7ine, common medium. ',pores; clear,

smooth. boundary.

15 cm Dark reddish brown2.5 YR 3/4 moist);clay; strongly developed, very fine,angular biockY aggregates; slightlyhard dry, friable moist, sticky non-plastic wet; continous, thinferriargillans; many very fine, manyfine, COMMOB medium Pores; clear,smooth boundary,

Dark red (2,5 YR 216 moist) and darkreddish brown (2,5 YR 3/ii dry); clay;weakly developed, coarse, T)rismaticprimary structures breaking intostrongly developed very fine, angularblocky aggregates;'slightly hard dry,friable moist, sticky non-plastic wet.continuous thin, ferriargillans, many'micro, many very fine, many fin, commonmedium pores gradual smooth boundary;

Dark re,alsh brown (2.5 YR moisu);clay; we_1:: develolped, coarse, prismatic

suctures breaking intostrongly developed, fine, angularlocky . .'ogates; very hard dry;

friable loist, sticky non-lastic wetcontineus, thick ferriargillans;many micro, many very fine, many fine,coarse medium -pores;

Laboratory dataDeDth (cm)

0-15 15-45 45-105 105-195

Texture (%, mm)

45-105 cm

105-195 cm

2-0.2 11 4 2 100.2-0.050.05-0.002

A,15

4

7

14

3

130.002 67 84 92 77

0-1H

1.r\ 00

OO

O C

O(f) tr's O

v) If, O O

cr.-)r,

H H

c-r)(N

J

tr//",

O O

OD

!a£.

1.1"\......1'

..,.Z.'

CD

() C)

I..C\

,r)LC

',(:).

(.71 CA

1-1 C) (N

Ir--1

r-4r--4

0-) -LT,.!

0=

i0

(.3r-i

4-)1.;',

{Y)

HP

iI..r,

CÜ

l 0(..P

\ 0 0(.,)

,--1Q

..).

)51(LT

),ir \

.4',z1-

0 ,-.-4c--- ',..0

,..-1-,,c) c)

; I, t'nr--i C

j CY

\C

),--I

,-----4

.):)..tC

r)(:).C

")r-i

Cr)

Lr-cv 0

0 (Ai

(j.)\.r.)

r)C

O -..7.1" 0

C7'. C

\-j0

CY

)

toCE

iOH

:cs,,-------P

----h

cá...1

P,o

Oif'', P

.',

0 -P ')0'rj

4----.

(\,,,r i

LO'11

0 W ,--- ------

',II,,S

fl,c.)0

0M

I.,:Ù

0+

r--IJ 0 ,---

41)G

)O

r-IC

.),--1c ---PFT.;

Cfri

,---1

r-.1r-i

L))C

,:,..2.2.t)1.) "-a-;

;.,11cC

kl),;,,t-T

r'..15-4

.

, -o a)

..,7.l

cá.) .4

,.0,J.D

.-:74-1cá

ccicá Q

....-H

,c .--P

.,' Hr--,,

c:..)co'l)

cettO .-P°

i7,-4' cdr-i

(-r- -1

C-)

',70X

P4tal

,72;q...1 0 E

-4 0 < 41!,

rO

LUVISOLS

5.19.1 FAO classificat-ionLuvisols are soils having an argillic horizon which hasa TDase-saturation. of 50 percent or more (by EHIpc) at leastin the lower part of the .7, horizon within 125 cm of the surface;lacking a manic A horizon; lacking the albic E horiz;on over-lying a slowly permeable horizon, the distribution pattern ofthe clay and the tonguing which are characteristic for Placosols,Nitosols and Podzoluvisols respectively; lacking an aridicmoisture regizte.

Orthic.Luvisols are Luvisols havin.f.T, an argiTlic E horizonwhich is not strong browrt to red; lacking an albic E horizon;lackinc, a calcic horizon, a y-psic horizon and concentrationsof soft -Dowdery lime within 125 cm of the surface; lackingferric and vertic properties; lacking olinthite within 125 cmof the surfae; lacking hydromorphic properties within 50 cmof the surface.

Chromc Luvisols are Luvisols havinP, a strong brown to redargillfo B horizon; lacking vertic and ferric properties;lacking an albic E horizon; lacking a calcic horizon andconcentrations of soft powdery lime within 125 cm of thesurface; lacking painthite within 125 cm of the surface;lacking hydromorphic properties within 50 cm of the surface.

Calcic Cambisols are Luvisols having a calcic horizon orconcentrations of soft powdery lime, or both, within 125 cmof the surface; lacking vertic properties; lacking an albicE horizon; lacking Dlinthite within 125 cm of the surface;lacking hydromorDhic properties t,:ithin 50 cm of the surface.

Vertic Luvisols are Luvisols showiEg vertic properties;lacking an chic f, horizon; lacking plinthite within 125 cmof the surface; lacking hydromorphic prolDerties within 50 cm .

of the surface.

Ferric Luvisols are Luvisols showing ferric properties;lacking vertic properties; lacking an albic E horizon; lackinga calcic horizon and concentratons of soft powdery lime within125 cm of the surface; lack-irlg plinthite s,,Tthin 125 cm of thesurface; lacking hyd'romorphic properties within 50'Pm of the surface.

Albic Luvisols are Luvisols having an arbic E horisOn;lacking plintite within 125 cm of the surface; lackinghydromorphic properties within 50 cm of thr- surfaee

Plinthie Luvisols are Luvisols having plinthite within125 cm of the surface.

Gleyic Luvisols are Luvisols having hydromorphic propertieswithin 50 cm of the surface; lacking plinthite within 125 cmof the surface.

5.19.2 General environment

Luvisols occur throughout the country where climatic

conditions are favourable for clay movenent, without having

strong leaching characteristics_ These conditions are met inareas with a pronounced wet and a pronounced dry season.

Luvisols do not occur in the arid and desert areas ofnorthern Eritrea, the Afar Triangle and the Ogaden. Nor do theyoccur in the :.det areas of the west and in the areas with higherrainfall in Gander and Sidamo.

In the central and eastern highlands Luvisols areassociated with Eutric Nitosols; the latter occuring on thP

relatively flat areas, the Luvisols on the steeper slopes. In

the drier areas, especially the northern highlands and in thesouthern lowlands, Luvisols are associated with Cambisols; theLuvisols occuring on the flatter land.

5.19.3 CharacteristicsLuvisols are soi.o having a distinct argillic 8 horizon

and a base saturation of 50 percent or more. Generally thesesoils have good chemical conditions: basa saturation is high

5-210

and they have weatherable minerals, Physically, these soilsvary widely. In soils with a heavy textured B horizon,permeability may be restricted and root development impeded.Vertic Luvisols tend to behaVe like Vertisols.

In the central and eastern highlands, Luvisols occur onsteep slopes and are often stony.

5.19.4 Land use and natural vegetation, . .

Luvisols are almost exclUsively intensively cultivated.Only on the very sca.. :':opes in areas with a mod ratepopulation, the ston,v Hvisois are Lz.-,22d for peasant liveStockgrazing, while the flatter land is L.,Ing cultivated, Also

the flat areas, often In depressions, with water logging condit-ions during the rainy. ., are dominantly used for grazing.

5J9,5 Management

LuvisoTsare tle best agricultural land in thetropiCs. Limiting frctors for aqricu1ture can be si7.bine.:,.sand steep slopes. In the lattr case, -nese Soils needterracing to prevent seve? .;ion. Permeability, drainageand workability can be a pro 7rm in the heavy textured Luvisols.

5.19.6 Occurence

Plinthic, Albic and Ferric Luvisois are not reported inEthiopia. Calcic Luvisols can occur in the semi-aria regions.Orthic Luvisois mostly occur around Lake lana, they have stonyphases. Chromic, Vert'ic and Glr,yic Luwisols occur in the

5-211

northern-, central - and eastern highlands and in the souternlowlands, the Vertic and especially the Gleyic Luvisols mainlyoccuring an flat land,

5.19.7 Profile descriptions

,19.7.1 Chromic Luvisol, Humera

This profile was taken several kilometers east-northeastof Adabai. it is typical for the somewhat high, isolatedconvex areas in the Vertisol plain. The soils are developedin granite material.

The annual rainfall ranges from 570 ot 650 mm which nearlyall falls from May throuclh SepteoTher.

Source: HUMERA

Tabeldi series De,=p, dark -reddish brown soils with an argillicB horizon.

A) General

Tabeldi soils occur on level to somewhat convex positions(pediments) in residual deposits. They are deep and have a darkreddish brown color. Their B horizon is characterised by clayaccumulation. Soils are neutral to slightly acid arad non-calcareous. The surface horizon is hard and massive when dry.

Profile description

Profile no: 7,,04

Soil name: Tabeldi SeriesClassification: Chromic LuvisolLocation: 8 km, ESE of Adabai,

14° 12'N and 360 48'E

Elevation: approximately 600 m

Physiographic position:Surrounding landform:Slope:Vegetation

Rainfall:Parent material:

Profile description:

0-18 cm Al

18-30 cm. h3

30-45 cm. 52t

5-94

r 9/

level, somewhat convex pedimentp_Lc1.14L

0-2 percenttree vegetationt Dalbergia melanoxylon,Solerocarya birroa and Adansoniaabout 600 mmgranite

Dark red (2.5 YR 3/5) moist and darkreddish brown (2.5 YR 3/4) dry, sandyloas with very few small sub-rounded.i7ran¡i¡:, gravel; massive structure;

non-sticky and non-plastic, friable,hard when dry; non-calcareous; fewvery fine roots, occasional mediumroots; c-iear smooth boundary; ph 7.0.

Dark ved (2,5 YR 3V5) moist and dry,sandy clay loam with very few smallgranite gravel; massive structure;siightly stcky and non-plastic,friable, very hard; non-calcareous;few -very fine roots, occasional mediumroosz clear mooth boundary, pH

Dark reddish brown (2.5 YR 3/4) bothmoist and dry, sandy clay loam withvery few smaal granite gravel; weakmoderate subangular blocky structurewith T-)atchy thin clay films mostly onped faces; slightly sticky and plastic,firm very hard; non-calcareous; veryfew fine roots; few termite burrows;gradual smooth boundary; pH 7.3.

Dark reddish brown (5 YR 3/4) moist and-reddish brown (5 YR 4/4) dry, sandy clayloam with frequent small and large granitegravel; massive structure; sliAThtlysticky and plastic, firm, very hard;non-calcareous; occasional fine roots;few termite burrows; clear wavyboundary; pH

Soluble cations(me/100 1:5)g,

pH (1-120,15)CaCOEC (Mmhos/cm,sat.ex)

7.h0.020.1

7.4tr0.1

'7 1, --

0.010.1

1./0.040,3

Exchangeable cations(me/100g)

Ca 8.2 10.3 12.4 17.2Mg 3.7 5.1 5.6 7.5K 0.3 0.1 0.2 0.2Na 0.1 0.1 0.1 0.1sum 12.3 15.5 18.1 24.9

CEC (me/100 g) 15.1 17.6 20.7 26.3Base saturation (5) 81 89 87 95

2-0,2 14 04 49 7 '-_,-__,

0,2-0.5 zc, :-?.a 45 190.5-0.02 25 22 42 120.02-0.002 25 25 ..",,

..7>LI 13

Ca 0.3 0.1 0,2 0.2Mg 0.2 0.1 0.1 0.1K 0.0 tr tr trNa n .o,J 0.1 0.2 0.1sum 0.7 0.2 0.5 0.5

914-130 cm. C Somewhat cemented horizon of smalland large angular granite gravel,partly weathered.

130-200 cm. R Strongly weathered grardte bedrock.

Moist col,.yrs of the A horizon may range from dark reddishbrown to dark red. Organic matter content values of theA horizon are below 0.5 percent. Dominant textures of theA horizon are sandy loam and sandy clay loaffl. Structure istypically massive and hard or very hard when dry.

Characteristic B2 colors are dark reddish bromrne texturemay range from sandy clay to sandy clay loam. The C horizonquite variable both in composition and depth. Soil reactionmay range from neutral to slightly acid.

C) Laboratory dataDepth (cm)

0-16 18-30 3o-45 245-9hTexture (%, '

5-214

5.19.7.2 Chromic Luvisol (Stony -ha Mekele

This soil is takPn a dolerte intrusion on the MekelePlateau. The parent material is medium to fine textured, noncalce eous and very low in quart .

Source: i-GRA,

Romanat series - Moderate y deep reddish brown sami: clay loanwell drained profiles.

A) General

Environmental Characteristics The series occurs extensively onthe undulating plateau areas formed on dolerte sills as wellas on the more ley& and less eroded-sites on the AdigratBid9:es The land slope is 1,712.:T in the range 2 to 7 percent,The present landuse is either cereal cult¡vntion or livestockbrowsing, depending largely upon the degree of surfacestoniness.

Profile Characteristics: Thh Sol is overlaid by a varied.quantity of stones and boulders of dolerite, and. limestone insome places. The upper horizon is re'ddisin brown with sandyloan: to loamy saipd texture and. weak angular blocky structure.Below 10 to 15 cm the texture is finer, usually sandy clayloen to clay loam, and colours are dark reddish brown toreddish brown (5 IR 3/3-4/4); rarely the textures are sandyloam. The stIlture in this hovizon is strong medium angularblocky to weakly prismatic. Below 75 cm the profile gradesinto soft weathered dlerite rock which has a gritty loamy

Soluble anions(me/100 g, 1:5)CO3 In

l3-30

ri

Depth (cm)

30-k5

111

45-94

PA

HCO3 04 0,2 0.1 0.901 0.3 Ir 0.3 0.3SOLI tr tr Ir trNO tr tr tr 0.1

Org. () 0.11 0.2 0.2 0.1

Tot.78,. h, (%) 0.05 0,03 0c))4 o.04r, /,..,,,/,

P00,(ppm),

7,

7i

20nm

5

m

m

-,

111

m

5-215

sand to sandy loam texture. Resistant cores of dolerte orbasalt are common. Solid rock occurs at below 100 cm, Thesoils are non-calcareous, and porous, especially in thesurface, here the roots are concentrated. Some roots .

penetrate the weathered subsoil,

Analytical Characteristics: The soils are slightly acid toslio..htly alkaline, with very high base saturation. Exchangeablecalcium is high to very high, and magnesium medium to veryhigh. Sodium is sometimes medium in the topsoil. Solublecopper and zinc are very low.

Land Capability Characteristics: Romanat soils usually occuron sites which are topogra-bhically suited ro cultivation withmoderate conservation measures but some sites are too steepfor cultivation and should be retained under protectivevegetation. The soils are generally moderately deep and thefine textured lower hori%on. should.. orovide a reasonablerootinp: medium. The soil surface tends to seal rapidly,probably due to relatively high silt contents, and thereforespecial cultivation practices will be required to ensurethat maximum rainfall enters the profile. In general thesoils are suited so dryland arable cultivation (ClassesII or III).

Associated Soils.: The Romanat soils occur on the upperplateaux in dolerte areas and also locally on the lower pedimentin association soils, which lack the fine textured S horizon andprobably represent a truncated version of Romanat Series. On

adjacent steep slopes are soils which are very. shallow Lithosolsover solid dolerites-

PA-ofile description

- Information on the site:Profile no.: MS/1

Soil neme; Romanat seriesClassification: Chromic LuvisolDate: 27 March 1975Author: K.J. VirgoLocation: 15 km NW Mekele, Tigray

Tselwa, Mekele-Hagere Selam Old Road

Elevation:Physiographic position:

Surrounding landform:Microtopograghy:

Slope:Landuse:Vegetation:T3ainfall

information on the soil:Parent material:Drainage-profile1,rainage-site:Moisture condition:.Flood hazard:Depth of groundwater:Surface condition:Evidence of erosion:

Profile description

Well defind reddish brovn sandy loam plough aayer, moderatesubangular blocky structure overlying compact dark reddishbrown clay loam subsoil with strong angular block structureand many burrows of subsoil faun., This overlies gritty sandyclay loam of weathered dolenito inclusions of dark sUbsoildown cracks. Below 130 cm is har.fi in nitu weathered dolentewith fresh corestones,

15-75 ern

5-'715

1900 mdolerte plateau, edge of westfacing escarpmentundulating convex plateauresistant dolerte corestones (to2m dir,meter) on surface; cultivationterrace to 50 cm highPr-rrnt

arablecereaas, few weeks650 mm

in situ weathered dolerit6,well drainedreceiving sitedry throughoutnonenot encountereddolerte boulderscultivation terraces 50 cm high

Reddish brown (5 TR 4/4) heavy sandyIlocin moderate medium subangularblocky: dry and sii.q.htly hard; manymedium and fine tubular pores; manyfine roots; abruTt smooth boundary.

Dark r,-,ddif;h brown (5 YR 3/2) clay loamto clay:, strong medium angular blocky;dry hard; few tubular fine ipores; few.fineroots-traces of faunal burrows(1 cm); clear smooth boundary.

0-15 cm