CORROSION OF CONCRETE FOUNDATIONS IN (POTENTIAL) ACID SULPHATE SOILS AND SUBSOILS IN THE NETHERLANDS

A.F.van Holst and G.J.W.Westerve2d ,soil Survey I n s t i t u t e , Wageningen

I. Introduction

The great expansion of the cities in the west of The Netherlands is largely ta-

king place in areas with a subsoil Of low bearing capacity. On such building si-

tes large constructions require a foundation of piles, even after the surface is heightened by the addition Of sand. Concrete piles are usually employed, ei- ther prefabricated or constructed in situ. When the latter type of concrete pi- les is used in an environment which can be considered agressive, the problem of

concrete corrosion arises, which is the subject of this paper.

2. Construction of concrete piles in situ

The procedure followed in making a concrete pile in the ground, the so-called

Franki pile, is as fOllows ( 1 ) :

At the place where the pile is to be driven, a hollow steel casing pipe, the bot-

tom of which is filled with gravel and/or concrete, is driven into the ground

until it reaches the layer with adequate bearing capacity.

block, the concrete in the pipe is driven out to form a plug under the casing

pipe. Reinforcement is then introduced into the pipe and the construction of the

By means of a heavy

is continued. This consists of pouring in a quantity of moist concrete, pul-

ling up the casing pipe a certain distance, and stamping the concrete with the

block. This procedure is continued Until the Pile reaches the required length. The result of this method is that in the core of the pile the strength of the con-

crete is greater and the porosity is lower than on the outside of the pile.

3 . Soil conditions at the building site

A building site where these Franki piles are employed is located in the municipa-

lity of Vlaardingen, which forms part Of the agglomeration of the city of Rotter-

dam ( ~ i ~ . ] ) . DO^ to great depth, the soil consists of Holocene marine clay de-

posits which, especially towards the surface, are interlayered by thick peat

layers. part from the fill sand which is added in the course of building opera-

tions, the original soil consists of non-calcareous clay overlying peat. This

peat layer rests on mainly calcareous marine deposits which are described as old

sea clay or sediments of Calais ( 6 ) . The upper part of these sediments consists

of non-calcareous potential cat clay.

37 3

Characteristic of the landscape in which the building site is found is the occur-

rence of creek ridges and basins, as a result of which soil conditions vary great-

ly over short distances. Quite different from the above description, which con-

cerns a basin soil (Table I, Profile No.II), is the soil given in Table I as Pro- file No.1, which comes from a creek ridge with a thick calcareous clay layer

overlying the peat. The subsoil is similar in both soils (2,3).

4 . Complications after construction of the piles

After the required 28-day period of hardening, the upper part of a number of pi-

les situated close to one another, mainly in the soils of the creek ridge (Pro-

file No.I), was not sufficiently hardened. This was apparent both from the pre-

sence of patches of white precipitate on the outside of the piles and also, par-

ticularly, from the occurrence of soft and porous spots down to about 2 meter from

the top. This different quality in a number of the Franki piles was sufficient

ground to condemn all the piles and to set up an investigation into the possible

causes.

The investigation covered the construction of the piles, the quality of the con-

crete, and the local soil conditions. It revealed that no mistakes had been made

in the construction of the piles ( I ) .

Without the correct reason for the insufficient hardening having been found, new

piles were driven (320 of them, each some 20 m long). In the meantime soil inves- tigations had demonstrated the presence of sulphidic or potential acid sulphatic

subsoil layers. As a result, the concrete covering of the reinforcement was in-

creased from 4 . 7 to 7 . 2 cm. Further, to increase the concrete strength in the

heart of the piles, the concrete was more condensed. After the hardening period

the same phenomena appeared as in the first series: a locally low degree of har-

dening, a porous structure, and a white precipitate on the ballast materials

(gravel and sand) in the concrete.

5 . Some chemical characteristics of the environment

Chemical investigation of the soil samples revealed that the piles had been pla-

ced not in an acid, but in a potential strongly acid environment (Table I). Except

in those samples derived from calcareous layers, the pH level showed a sharp to

very sharp drop following oxidation with H202-30%. Due to the lack of sufficient

buffering compounds (CaCo,), this drop is to a large extent caused by S O 4 , formed

3 7 4

6. Sulphates as concrete corrosive agent

It is known from literature (5) that sulphates are among the strongly corrosive agents for concrete. It is here a question of already hardened concrete which is

exposed to a continual supply of sulphate carried by water. The accepted limits

for water which is not aggressive to concrete vary. For running water it amounts

to an average of 200 to 300 mg S o h / ] and for stagnant water 500 to 600 mg/l. Water with more than 1000 mg/l is always aggressive ( 4 , 7 ) .

In an environment with a sufficiently high sulphate level, concrete can corrode.

This can happen in two different ways:

1. Sulphates can cause the formation of ettringite ("cement bacillus") (1, 4 ) .

In this formation, the tricalcium aluminate (3CaO.A1203), one of the concrete

components, reacts with gypsum originating both from the sulphate in the ground-

water and from Ca(OH)2 in the concrete. This results in the formation of the not

readily soluble calcium sulfo-aluminate hydrate (3Ca0.A1303.3CaS0t+.32H20). The

great increase in volume due to this crystallisation exercises heavy pressure on

the surrounding concrete, reducing its strength.

2. Sulphates can also cause the formation of gypsum ( 1 , 4 ) , which is also coupled

with an increase of volume, although to a lesser extent than with ettringite.

375

The Ca(OH), liberated in the hydration of the cement reacts with the sulphates

in the (ground)water. If the sulphate content is high enough, this results in

the precipitation of gypsum on the concrete. The increase of volume occurs in the

porous concrete, due to the fact that gypsum crystallizes with two molecules of

crystalwater. This may also contribute to a reduction of the strength of the con-

crete.

7. Investigation of the concrete files

Tests carried out on the concrete, which were not done by our Institute, included

the analysis of several pieces of the corroded piles. The results of these tests

were ( 1 ) :

a) X-ray diffraction revealed small quantities of ettringite on the exterior of

the concrete piles;

b) The infra-red analysis method identified the white precipitate on the ballast

materials and the cement on the exterior of the piles as gypsum;

c) The cement compound of the concrete revealed no significant change in sulphate

content from the heart of the pile outwards. Moreover, the sulphate content of

the exterior of the pile was the same as that of uncorroded piles.

During construction of the piles, the fresh, condensed concrete comes into contact

with the groundwater and sulphidic soil material. This may have resulted in the

formation of the white gypsum precipitate. The consequent increase in volume

may have reduced the strength of the concrete at the exterior of the piles. The

absence of mass transport of sulphates as a result of the stagnant groundwater

implies a low rate of formation of ettringite.

Although it is not quite clear which particular mechanism caused this case of

unsatisfactory hardening of the concrete, we can nevertheless draw the conclusion

that sulphates probably had a great deal to do with it.

8 . Experiments

Indications of the influence of this aggressive environment on concrete corrosion

were brought to light in laboratory experiments with different mixtures of earth-

slag cement pastes ( 1 ) . I n each case cement was mixed with 5% of soil derived from samples from various soil layers. The analytical data on this soil material

are not available, but are more or less comparable with those given in Tabel I

for similar soil layers. The setting time required for complete cementation of

these mixtures was determined. The resulting retardation with respect to pure

376

slag cement is greatest with mixtures consisting of cement past with reed (sedge)

peat (Fig.2). In these mixtures a great quantity of sulphidic material i s present.

It is not excluded that under these experimental conditions the sulphidic materi-

al was partly oxidised.

In another laboratory experiment the crushing strength of various soil-cement

mixtures was determined after the 28-day hardening period (Fig.3). ~t appeared

that the nature and quantity Of the admixture of sulphidic material is the de-

termining factor with respect to the ultimate strength.

It can also be concluded that organic matter components (humic acids) also act

upon the concrete and result in a retarded bond and a lesser degree of hardening.

These phenomena occur especially when a large quantity Of organic material is

present (Fig.2 and 3). The presence of Peat layers in the neighbourhood of the

piles will certainly have harmful effects

ted from the corrosion that is due to sulphates. The results of both experiments cannot he properly applied in practice when the

fresh concrete meets the various sulphidic soil layers. Here the interactions will

be limited to the exterior of the pile, while in the laboratory, it is more a

question of a bulk process.

9. Conclusions

It is known that concrete can be corroded by sulphates. In the case of this paper

the corrosion of the concrete piles poured in situ, which became apparent from

the unsatisfactory hardening of the concrete, occurred in an environment with

a potential very high sulphate content. The mechanism involved is not well under-

stood, but the cause of the corrosion is probably sulphates. This means that using

this method of piling in areas with sulphidic subsoil material, entails a high

risk of damage to hardening concrete.

In areas where potential acid sulphate subsoils are expected to occur, a prelimi-

nary soil investigation should be carried out.

presence of such soils, it is recommended that Franki piles not be used for foun-

dations in such areas, but that a sulphate-resistent blast-furnace cement or

prefabricated concrete piles with a bitumen coating be used.

( 4 ) , although these cannot be separa-

If the investigation reveals the

10. Acknowledgement

The authors wish to thank Dr Ir H.W. van der Mare1 and Ir A.Breeuwsma of the

Department of Soil Chemistry and Clay Hineralogy (Soil Survey Institute, Wagenin-

gen, The Netherlands) for critical reading of the manuscript.

377

w u m

TABLE I .

SOME ANALYTICAL DATA OF THE DISCUSSED PROFILES

Total amount

+ sulphates

Depth Estimated Organic pH - H20

af percenta- matter before oxydation after oxi- Of

in cm on < 2 pm ’ moist Depth Description sample ge fracti- after dation in cm drying with H202 expressed ( 3 0 % ) SO$- in % of sample

dry soil

PROFILE I

0-60 60-80 80-100

100-150 150-215 215-240 2 4 O - 2 5 O 250-265 265-285 285-290 290-310 310-400

fill sand non-calcareous marine deposit non-calcareous marine deposit calcareous marine deposit calcareous marine deposit detritus reed-sedge peat sedge peat detritus clay with remnants of reed non-calcareous marine deposit calcareous marine deposit do.

400-450 do. 450-550 do.

PROFILE I1

0-100 fill sand 100-110 non-calcareous marine deposit 110-130 non-calcareous marine deposit 130-150 moulded peat 150-190 reed-sedge peat 190-200 peaty clay 200-240 reed-sedge peat 240-280 sedge peat 280-330 reed peat 330-370 sedge peat 370-420 clay with remnants of reed 420-430 non-calcareous marine deposit 430-520 calcareous marine deposit

65-75 85-100

110-130 170-200 220-230 240-250 255-265 270-280 2 8 5 - 2 9 O 290-305 3 10-320 350-370 410-420

110-130

150-190

200-240 240-280 280-330 330-370 370-420

440-500

4 0 44 32 30

38 2 3 2 3

4 .1 6 . 4 6 . 5 4 . 8 4 . 9 4 .9 7 . 4 6 .7

2 .7 8 .0 8.0 8.1 5.7 7 . 8 8 .0 7 . 9

2 6 . 3 7.7 7 . 5 4 . 1 6 0 . 5 6 .6 6 . 2 3 .1 5 7 . 2 7 . 3 6 .7 3 .8 6 8 . 8 6 . 4 5 . 3 3.6 16 .8 6 . 6 5 .7 4 . 1 5 .2 7 . 5 6 . 1 2 . 2 2.1 7 . 8 7 . 8 6 . 2 3 . 3 8 .0 7 . 7 7 . 4

30 4 .6 7 . 7 15

30 36 2 .9 6 . 5

7 1 . 8 5 . 2

- 6 . 1 7 8 . 2 6 . 6 7 9 . 1 6 .6 7 2 . 1 6 . 5 2 7 . 8 5 .1

28 18 1.6 7 . 5

7 . 5

6 . 3

4 .8

5 . 9 5 . 9 6 . 0 5 . 8 4 . 3

7 . 5

trace 0 . 1 2 0 . 0 2 2 . 9 8

1 0 . 5 5 11 .67

6 . 0 3 10.45

3 . 8 5 5 . 7 5 3 . 1 0 3 . 2 5

7 . 6 3 .96

4 . 8 0.11

2 . 0 8 . 4 4

2 . 0 2 . 2 5 . 4 2 2 . 2 6 . 8 7 2 . I 8.89 2 . 0 7 . 7 5

6 . 7 2 .47

Slag cement

do , 5% non-calcareous s i l t y c l a y

do I 5% calcareous c lay loam

do . 5% calcareous s i l t y c l a y

do I 5 % peaty c l a y

:3 ::I ::I ::1 - - I

Flg. 2 Seftlng t h e of slag cement paste compared Cith various slag cement-earth mlxture pastes (Data from Dlcke en Krekel (1).

do . 10% calcareous s i l t loam

do . 20% calcareous s i l t loam

do. , 5 % peaty c lay

do + 10% peaty c lay

do , 20% peaty c lay

do , 5% clay wl th remnants o1 reed

I

'1-1 . L n ':I do.,;~~,",I ye;1 th

Slag cemenl

do , 5O/. calcareous s i l t loam

I

Crushing strength in regard to s iag cement

1440kgfcm2 ~ 100%)

1- I I I I I I I 1 O0 200 300 400 1 560kg/cm2

Crushing strength

Fig. 3 Crushing strength of concrete cubes. made of slag cement and ditferent slag cement-earth mlxtures after complete hardenlng (Data from Dicke en Krekel (1).

380

REFERENCES

( 1 ) DICKE, H.A., KREKEL, H. 1968. Intern Rapport N.v.Nederlandse Franki ì,laat-

schappij. Rotterdam. Mimeograph.

(2) HOLST, A.F.van. 1968. Bodemkundig onderzoek van een bouwterrein in de

Holiërhoeksche Polder (Gemeente Vlaardingen). Rapport 778. stichting

Bodemkartering. Wageningen. Mimeograph.

(3) HOLST, A.F.van. 1968. Bodemkundig onderzoek van een bouwterrein in de

Holiërhoeksche Polder (blok G ) (Gemeente Vlaardingen). Rapport 778a. stich- ting voor Bodemkartering, Wageningen.

( 4 ) LOCHER, F.W., PISTERS, H. 1 9 6 4 . Beurteilung betonangreifender Wasser. zement, Kalk, Gips 4:129-136. Wiesbaden.

(5) LOCHER, F.W. 1967. Chemischer Angriff auf Beton. Beton 17: HI: 17-19. ~ 2 :

47-50. ~iisseldorf, Oberkassel.

(6) WALLENBURG, C.van. 1972. Cat-clay soils and potential cat-clays in inland

polders i n the western part of The Netherlands. Symposium on Acid Sulphate

soils, Wageningen.

(7) WERNER, R. 1961. Hochsulfat bestSndige Zemente in Berg-, Stollen- und Tun- nelbau. Montan Rundschau 4.

38 I

Summary

A case i s presented o f concrete p i l e s t h a t , being poured i n s i t u i n s u l p h i d i c subsoil, did not harden properly due to i n t e r f e rence o f water soluble SO4 i n the

s o i 1.

Résumé

On présente un cas de p i l o t i s en béton armé qu i , en é tan t déversés en place dans

un sous-sol sul furique, f a i l l i s s a i e n t à durcir proprement à cause de Z'action

corrosive du SO,-soluble dans l e sol.

Resumen

Se presente un cas0 de p i l o t e s de cemento armado que, siendo echados en e l sitio en un sub-suelo su l fu r i co , fal taban a endurecer correctamente a consecuencia

de l a accidn corrosiva d e l SOb-soluble en e l s o l .

Z u s m e n f a s s u n g

Die i m su l f i d re i chen (intergrund e ingese t z t en E'undmentpfähle aus armiertem Beton

wiesen e ine durch d i e Korrosionswirkung lösl icher Bodensulfate verursachte

mangeZ.hafte Verhärtung aus.

382

L-

RECLAMATION AND IMPROVEMENT OF ACID SULPHATE SOILS I N WEST VALAYSIA

K. Kanapathy Department of AgricuLture, West MaZaysia

Introduction

In West Malaysia Dennett J.A. 1933 ( 1 ) noted the presence of acid sulphate soils.

He found that they nearly always occurred in coastal alluvial areas and only oc-

casionally in inland quartzite valley areas. Wilshaw (2) and later Coulter (3) made considerable study on the nature and distribution of these soils. ore re- cently Chow and Ng ( 4 ) studied the amounts of sulphur extractable by various

reagents according to the methods adopted by Bloomfield and Coulter (5). The

author has for some years been attempting to reclaim or improve the acid sulphate

s o i l s for crop production. Under the present soil classification the acid sulpha-

te soils are tentatively known as the Telok, Linau and Guar Series. The area under

such soils in West Malaysia is estimated to be about 110 O00 hectares of which about 12 500 hectares are considered to be extremely acid. Of the less acid soils

about 25 O00 hectares are utilised for growing rice, most of which belongs to the

Telok series (Tab.]). Another 20 O00 hectares is under rubber and belongs to the

Linau series (Tab.2) and a similar area under a variety of crops like rubber, oil

palm, coconuts, coffee and vegetables. The yields of these crops vary consi-

derably and could be severely reduced following prolonged periods of drought. The

remaining area Of about 45 000 hectares which includes the 25 O00 hectares of very acid areas is under swamp forest, mainly Nipah (Nipa fruticans) or Gelam (Gelam malacanensis).

Analysis of acid sulphate soils

Acid sulphate soils have been analysed for various constituents Erom time to time and these are given in Table 1 to 4 .

All values of pH are based on a soil: water ratio of 1 : 2 . 5 , distilled water as

the medium and using glass electrode.

~ ~ ~ t ~ r ~ involved in the improvement and reclamation

The factors which form the basis for the improvement and reclamation can be

briefly summarised as fOllOWS:

1 . Under the high rainfall conditions existing in West Malaysia (2000-3000

per annum) soluble salts including sulphates would be washed out from the root

zone on drainage. The conductivity of well drained soils is generally below 0.1

383

m.mhos. Drainage is therefore the key to improvement and reclamation.

2. The amount of sulphur and acidity increases with depth and the water

table is not lowered by drainage to a greater depth than necessary.

3 . Drain water in acid sulphate areas contains sulphate which has heen

leached out by rain. Drains are made efficient so that flooding with such water

is reduced and the drain water is discharged into a river or sea.

4 . Since drainage is of vital importance in oxidising the sulphur to sulpha-

te and for eventual removal of the latter, the method of cultivation and other

practices are such that drainage is not hampered.

5. Addition of lime and basic fertilizers not containing sulphate is prac-

tised.

6 . Agronomic practices take into consideration that the sub-soil is mere

acid. Flanting is shallow and use is made of limed top soil built into a mound

around the trees or of high beds made of limed top soil for annual crops.

7. In order to reduce cost of liming acid tolerant crops are being attempted

Tests carried out on acid sulphate soils

With the understanding of the factors involved several tests on the reclamation

and improvement are being attempted.

Laboratory and pot tests

Leaching of acid sulphate soils with distilled water increased the pH from

3.0-3.6 to 3.5-4.2 while water logging the soils in pots gave the following

results :

Time in days 1 1 2 45 6 3 80 pH in situ 2 .60 3 .30 4 .47 6 . 0 0 6 . 3 0

This suggests that even very acid soils could he used for growing rice under floo-

ded conditions or made into fish ponds if good water is available.

Field tests

A liming test was carried out in an oil palm area where owing to a fairly pro-

longed drought at the beginning of 1963 fronds were severely scorched. In keep-

ing with the idea that deep drainage would he had particularly when a crop is

standing, drains were kept at a depth of about a meter. Limestone powder was

used and this was broadcast after slashing the weeds, no attempt was made to in-

corporate it into the soil which was not very permeable. The results of the li-

ming test on the soil reaction and the yield of fresh fruit bunches for four

years 1965-1968 inclusive are given in Table 5 .

384

Considering t h a t they were 20 Year o ld "dura" o i l palms the y i e l d of t he palms

must be considered a s good.

I n another a r e 15 year o ld "dura" palms were g iv ing an annual y i e l d of about

25 tons F.F.B. o r 5 tons o i l Per h e c t a r e wi th ha rd ly any response t o f e r t i l i z e r

on an ac id su lpha te s o i l t he Ph of which i s given i n Table 6 .

The f a c t t h a t o i l palm i s t o l e r a n t t o a c i d i t y has a l s o been noted by Bloomfield

and o t h e r s bu t according t o them liming has no apprec i ab le e f f e c t on the a c i d i t y

of t he s o i l which i s con t r a ry t o t h e r e s u l t s ob ta ined .

The coconut is a l s o t o l e r a n t t o a c i d i t y . A r ecen t a n a l y s i s of a s o i l from a CO-

conut a rea p lan ted l a r g e l y with semi - t a l l s and dwarfs g iv ing a y i e l d of 2.5

tons jha of copra per annum i s given i n Table 7 .

I t has been found more r e c e n t l y t h a t t a l l coconuts a r e even more r e s i s t a n t t o

a c i d i t y than semi - t a l l s o r dwarfs. With the knowledge t h a t t r o p i c a l crops can

wi ths tand high a c i d i t y , o i l palm, coconut, co f fee and p ineapples have been plan-

ted on ac id su lpha te s o i l s . Liming on a moderate s c a l e t h a t i s with O , 2 .5 , 5.0

and 7.5 tons /ha l imes tone powder i s be ing t r i e d . P lans a r e ready f o r t e s t i n g va-

r ious t r o p i c a l f r u i t t r e e s f o r t h e i r t o l e rance t o a c i d i t y . Since the sub-so i l i s

more a c i d , p l a n t s a r e p l an ted i n shallow ho le s and limed top s o i l i s used t o make

a mound round the t r e e s . This no t only se rves t o provide a l e s s su lphur con ta in ing

s o i l bu t a l s o p r o t e c t s t he t r e e s from water-logging. I n t h i s connec t ion i t i s t o

be noted t h a t vege tab le farmers on such s o i l s make high r a i s e d beds with top

s o i l s and use rubber smoke house ash and o the r such m a t e r i a l s i n o rde r t o r a i s e

t h e i r c rops .

Discussion and recommendation

It has been the opin ion of some expe r t s t h a t ac id su lpha te s o i l s would r e q u i r e

l a r g e q u a n t i t i e s of l ime and would be uneconomical t o rec la im. This i s probably

based on the amount of l ime r equ i r ed t o r a i s e t h e s o i l pH from 3.5 t o 5 .5 and i s

c a l c u l a t e d t o be about 25 tons /ha . This i nc rease of pH t o 5 .5 appears t o be un-

necessary f o r most t r o p i c a l c rops . Apart from o i l palm and coconut i t appears t h a t

c o f f e e , p ineapples , Napier Grass, Rubber and Tapioca (cassava) could t o l e r a t e

a c i d i t y . The a d d i t i o n of l a r g e q u a n t i t i e s of lime t o grow such crops c r e a t e s pro-

blems of potash and t r a c e element, p a r t i c u l a r l y manganese d e f i c i e n c i e s . I t i s

no t advisable t o grow corn (zea mays) as i t does r e q u i r e a pH of 5 and above. I f

every a t tempt has been made t o remove so lub le s a l t s and ac ids wi th e f f i c i e n t bu t

shallow d r a i n s the pH of t he s o i l i n t h e r o o t zone would r i s e t o about 3 . 5 t o 4 . 0 .

385

As shown in the test liming of such soils with a few tons of lime per hectare

would raise the pH sufficiently to allow acid tolerant crops to grow. The use

of wood ash and other plant ashes is highly desirable since it neutralizes but

does not depress the uptake of potash and trace elements.

In areas where crops have already been planted drainage needs to be improved

gradually and at the same time the soil could be limed. Drains need to be effi-

cient so that flooding with drain water does not occur frequently. Every attempt

needs to be made to keep the soil permeable to facilitate drainage and removal

of sulphate. With these ideas attempts are being made to reclaim and/or improve

acid sulphate soils.

Acknowledgement

The author is grateful to the Director General of Agriculture, West Malaysia,

for permission to present this paper.

386

TABLE I .

SULPHUR CONTENT OF SOILS ON DRY BASIS (PERCENT) (TELOK SERIES, KEDAH)

Depth Water s o l 2N HC1-sol. Total sou - s sob - s in cm PH dry

5

0-15 3.5-4.3 0.01-0.07 0.04-0.11 O . 16-0.43

O . 13-0.48 15-30 3.2-4.2 0.01-0.03 0.03-0.09

0.12-1.19 30-60 2.3-3.3 0.01-0.28 0.03-0.64

Below 60 2.3-3.7 0.01-0.52 0.05-0.94 O . 16-2.64

TABLE 2. ANALYSIS OF A LINAU SERLES PROFILE, JOHORE

Depth PH Cond. NaCl SO, Loss on Water ex trac e in cm fresh dry m.mhos % % ignition

9. Na ppm K ppm

35.5 27 27 - - 0-15 4.0 4.0 1.0

15-30 4.2 3.7 1.0 0 .02 0.04 16.8 20 45

30-45 4.4 3.4 2.6 0.02 0.36 18.2 27 35

45-60 4 .8 3.2 4.6 0 .03 1.11 16.1 67 70

60-90 5.0 3.5 5 .8 0.05 1.16 16.1 320 70

TABLE 3.

ANALYSIS OF ACID SULPHATE SOIL (PAKANG)

Depth PH Cond. in m.mhos c1 so4 Loss on in cm PPm PPm ignition

z fresh dry fresh d r y

0-15 3 .5 3.5 0.20 0.34 26 806 1 1

15-30 3.4 3.5 0.23 0 .43 9 I325 16

45-60 3.0 2.8 0.77 1 . 9 6 23 5655 16

75-90 3.2 2.7 0.69 3.08 35 5684 28

TABLE 4 .

VERY ACID SOIL - SWAMP JUST BEING DRAINED LINGGI SCHEME (MALACCA)

Depth PH Cond. C 1 SO, Loss on N C in cm dry m.hos ppm ppm ignition % %

% ~

0-15 3.1 0.57 180 1280 12.9 0.133 2 . 6 5

15-30 2.9 0.94 200 2040 15.3 0.083 3.26

30-60 2.4 2.60 240 8560 19.6 0.118 3.71

TABLE 5.

THE YIELD OF FRESH FRUIT BUNCHES FOR YEARS 1965/1968

5 I O 15 Time o f Depth tons,ha Bunch Waste Bunch Ash s a m p l i n g i n cm o L.S .P . L .S .P . L . S . P . loo 530 k g / h a

1964 0-15 3.50 b e f o r e liming 15-30 3.40

30-45 2.90

1966 0-15 3.75

15-30 3.62

1969 0-15 3.85

15-30 3.65

30-45 3.30

3.90

3.55

2.30

4.35

4.02

4 .33

4.10

3.51

3.60

3.45

2.85

4.63

4.27

4.70

4.58

3.76

3.75

3.45

2.85

4.73

4.24

4.80

4 .63

4.18

3.65

3.35

2.95

3.84

3.75

3.82

3.72

3.48

3.70

3.40

3.00

3.87

3.70

4 .13

4.00

3.52 ~~ _____ ~~

F.F.B. i n t o n s ( I ) 63 .8 65.7 75.7 72.6 79.5 78 .3

p e r h e c t a r e (2 ) 78.5 67 .8 73.2 76.1 90.1 72.1

TABLE 6 .

pH OF SOIL PROFILE (AIR DRIED)

Depth 0-15 15-30 30-60 60-90 90-120 120-150 i n . c m

P i t I 3.4 3 .5 3 .2 3.0 2 .6 2 .2

P i t 2 3 .9 3.6 3.1 2.7 2.4 2.1

P i t 3 4 .4 3 .6 3 .4 2.9 2.6 2 . 3

TABLE 7

SOIL FROM GOOD COCONUT AREA

Depth pH Cond. C a r b o n N i t r o g e n C / N L o s s o n i n cm a i r dry d m h o s % % i g n i t i o n %

0-15 4.0 0.048 2.19 0.25 8 . 8 14.1

15-30 3 . 8 0.049 2.09 0.19 10.8 14 .3

30-60 3.8 0.090 0.90 0 .15 6 .0 14.6

60-90 3.9 0.161 1.06 0 .14 7.5 1 4 . 7

388

REFERENCES

( I ) DENNETT, J.A. 1933. The ClaSSificakiOn aild properties of Malayan soils.

Ma1.Agric.J. VO1.21. No.8.

(2) wILSHAW, R.G.H. 1940. Notes on the development of high acidity in certain

coastal clay s o i l s of Malaya. Ma1.Agric.J. Vo1.28. ~ 0 . 8 .

(3) COULTER, J . K . 1952. Gelam Soils. Ma1.Agric.J. V01.35. No.].

( 4 ) CHOW, W . T . , NG, S . K . 1969. A Preliminary study of acid sulphate s o i l s in

west pfalaysia. Ma1.Agric.J. V o 1 . 4 7 . No.2.

(5) BLOOMFIELD, C., COULTER, J.K., "ARIES SATIRIOU. 1958. Oil Palms on Acid Sulphate Soils in Malaya. Trop.Agric. (Trin.) Vo1.45. ~0.4.

389

F

Summary

In Malaya acid sulphate s o i l s are successfully reclaimed f o r growing acid to l e ran t

crops (oilpalm, coffee, ' pineapple, cassava) by shatlow bu t e f f i c i e n t drainage

combined w i th moderate l i m i n g .

Résumé

Dans l a péninsule Malaise on récupère des sols sulTate's acide avec du succès

pour les cultures t o l é ran te s a m acides (palmier à 2 ' h u i l e , ca[é, ananas, manioc)

au moyen d 'un drainage peu profond mais t r è s e f f i c a c e combiné avec un chaulage

léger.

Resumen

En l a peninsula MaZaya se recupera los suelos de s 'ulfatos ácidos con é x i t o para

c u l t i v a s to l e ran te s a l a acidez (palma de a c e i t e , café, pina, yucca) por medio

de un drenaje poco profundo pero m y efficaz en combinación de un encalado mode-

rado.

Zusmmen f assung

Z m Anbau säuretoleranter Pflanzen (Olpalme, Kaffee, Ananas, uaniok) i n Malakka

werden d i e schwefelsauren Baden m i t Erfolg urbar gemacht durch d i e u n t i e f e , doch

wirkungsvoZZe Entuässerung, d ie m i t e iner l e i ch ten Kalkung kombiniert ist.

390

,A~,~ELIoRATION OF THREE ACID SULPHATE SOILS FOR LOWLAND RICE

F . N. Ponnamperma, Tasnee Attanandana end Gora Beye The International Rice Research I n s t i t u t e LOS Baños, Laguna, Phi Zippines

causes of OW productivity

The low productivity of acid sulphate soils has been attributed t o (a) excess

aluminium in the soil solution (5), (b) toxic effects of ferrous and aluminium

sulphates (13), (c) excess exchangeable aluminium and iron ( 3 0 ) , (d) low p~ per

(15) , (e) low nutrient Status ( 6 , 151, (f) iron toxicity ( 1 7 , 2 7 ) , (9) low

p ~ , aluminium toxicity, and phosphorus and micronutrient deficiencies (15, 25).

Amendments

helioration measures for lowland rice recommended by researchers or used by

farmers include: (a) prolonged submergence (farmers of Vietnam, Thailand, and

Kalimantan); (b) leaching the dry soil with rain water ( 5 ) ; (c) leaching the

dry soil with sea water followed by leaching with rain water (IO); (d) liming ( 1 9 ) ; ( e ) fertilization ( 6 ) ; ( f ) li-ing, application of manganese dioxide, and

prolonged submergence ( 1 7 ) ; (9) liming plus percolation (16) ; and (h) liming

double cropping ( 2 5 ) .

Rationale

The diversity of the reasons given for the low productivity of acid sulphate soils

and the multiplicity of the remedies indicate that acid sulphate soils vary in

their properties, or the problems they present are not clearly understood, or

both. If so, an analytical investigation of the problem is better than a search

for empirical amendments. The analytical approach requires a knowledge of the

chemical and physicochemical Properties of acid sulphate soils and the changes

they undergo when submerged. It also requires a knowledge of the physiology of

the rice plant.

39 1

P r o p e r t i e s o f a c i d s u l p h a t e soils

Acid sulphate soils are strongly acid clays with a high content of free and

adsorbed sulphate ( 7 ) . The pH ranges from O (13) to 4 . 5 ( 1 2 ) and the content

of water-soluble sulphate may be as high as 5 percent (32). These soils are ge-

nerally low in phosphorus and potassium, and they release less than 5 percent

of their total nitrogen during anaerobic incubation ( 1 2 ) , compared with 10

to 20% for other tropical soils. The content of active iron and manganese is

highly variable. So probably is the reactlivity of the hydrous oxides of iron

and manganese present in these soils. Table 1 reveals some of these differences.

Toxicity of acid sulphate soils

Table 1 reveals that the main obstacles co the growth of rice on soils B and

C (in the presence of sufficient N, P , K fertilizers) are excessive acidity per se and aluminium toxicity at planting. Chemical kinetics of submerged soils ( 2 0 )

suggests that a few weeks after planting excess water-soluble iron and excess

CO2 could retard the growth of rice on all three soils and excess electrolyte,

in soils B and C.

A c i d i t y and AZ t o x i c i t y

An acidity stronger than pH 4 . 0 harms higher plants directly ( 3 ) . Rice is no ex-

ception (18). Besides, a low pH aggravates the harmful effects of organic acids

(29). Aluminium at concentrations as low as 1 to 2 ppm is toxic to rice (6)

as it is to other cereals ( 1 1 ) .

According to the equation (26)

pAlm = 2 pH - 4.41 ( 1 )

the concentrations of AI at the pH values 3 . 4 , 3 . 6 , and 4 . 3 , the pH values of

soils C, B, and A, are 108 ppm, 4 3 ppm, and 1.7 ppm respectively. Thus acidity

per se and Al toxicity are likely to harm rice seedlings in soils B and C if

planted immediately after flooding. In soil A, acidity per se will not harm the

plants but Al may retard their growth. Both acid and Al injury can be elimina-

ted by raising the pH of the soils to 4 . 4 . The pH can be raised by liming or

keeping the soil submerged for several weeks before planting.

Iron t o x i c i t y

If acid and Al injury are averted, the plants are exposed to iron toxicity, for

at the pH and Eh values of submerged acid sulphate soils enormous amounts of

392

Fe2+ can be present in the Solution phase ( 1 7 ) . If "ferric hydroxide" is the

chief Fe (I1') oxide involved in reduction, the following relationships hold

( 2 1 , 2 2 , 2 4 )

(2)

( 3 )

Eh = 1.058 - 0.059 log Fe" - 0 . 1 7 7 p~

pE = 17.87 + pFe'+ - 3 pH

After the peak or water-soluble iron, FesO4.nHzO Or Fe,(OH), is probably present

( 2 4 ) , and if its solubility product is taken as 10-17'4 ( 2 )

pFe2+ = 2 pH - 10.8 ( 4 )

Equation ( 4 ) reveals that if solid phase FesOb.nH~0 is present, at a p~ of 6 . 0

the activity of Fe2+ in the soil solution should be

coefficient is assumed to be 0.5, the concentration is 2 x 10-"*M. Water-solu-

ble F ~ ~ + concentrations of this order were present in soil C, 2 weeks after

If the activity

-

(Fig.3), when the pH of the soil solution was about 6 .

F~~~~~~ iron at concentrations exceeding 500 ppm is toxic to rice ( 1 7 , 2 3 ) . Figure

3 shows that concentrations far in excess of this were present in soils B and c after 2 weeks of submergence.

toxicity can be alleviated by liming and by the addition of manganese dio-

xide (23). ~ i m e increases pH and lowers the concentration of water-soluble Fe2+;

M ~ O ~ retards soil reduction, depresses the concentration of water-soluble Fe2+,

and physiologically the adverse effects of excess iron ( 2 8 ) .

Carbon dioxide toxic7:ty

Carbon dioxide concentrations exceeding 0.15 percent retard water and nutrient

uptake by plants. Excess CO2 restricts the root growth of rice and causes wilting

of rice plants (20).

id soils build up high concentrations of C O 2 ( 8 ) . Carbon dioxide toxicity pro-

bably retards the growth of rice on submerged acid sulphate soils.

Salt injupg

A specific conductance exceeding 4 millimhos/cm at 25 OC indicates the presence

of t o o much electrolyte in the soil solution for normal growth of rice (9). Soils

B and C have excess electrolyte to Start with (Table I). Submerging these soils

aggravates salt injury because the specific conductance of soils increases on sub-

mergence ( 2 0 ) .

393

P

Salt injury can be minimized by leaching the soils with fresh water. Removal

of the salts (chiefly aluminium sulphate) should also lower acid and Al injury

and reduce HzS toxicity (because of the removal of sulphates).

Amelioration

Since leaching, liming, and adding Mn02 appeared to be promising amendments,

the influence of these treatments, singly and in factorial combination, on the

chemical kinetics and the growth of rice on soil A, B, and C was studied in the greenhouse.

Experimental

Twelve kilogram portions of the air-dry soil were placed in glazed 16-liter pots

fitted with tubes for sampling the soil solution. In the leaching treatments,

the soils were submerged, allowed to soak overnight, and drained the next day.

The operation was repeated 3 times. Just before planting, sufficient CaC03 to

raise the pH of each soil to 5.5, MnO2 at 0 .5%, and 75 ppm each of N, P , K as urea, triphos, and muriate of potash were incorporated. Two 2-week-old rice

seedlings were planted in each p o t . The soil solutions were sampled fortnightly

for 12 weeks. The pH, Eh, and specific conductance were read simultaneously in

an electrometric cell ( 8 ) . Chemical analysis was done by standard methods ( 1 ) .

The partial pressure of CO2 was determined by gas chromatography (9).

394

Chemica% kinetics of three soiZs

Differences among the s o i l s

The chemical and electrochemical kinetics of the three soils varied widely (Fig.

1, 2, 3 , 4 ) .

The increase in pH following submergence was rapid and large in soil C; it was

slow and small in soil A. Since the increase in pH of acid soils on submergence

is due to the reduction of hydrous oxides of Fe(111), the content of reducible

iron and its reactivity control the increase in pH. The content of iron is highest and most reactive (as we shall see later) in soil C. The content is least in soil

B. Soil A contains enough iron but apparently it i s not reactive.

Soils B and C maintained high concentrations of electrolyte throughout the period

of submergence (Fig.2).

The concentration of water-soluble iron was extraordinarily high in soil C, mode-

rately high in soil B, and unusually low in soil A (Fig.3). I n Table 2, the

E f f e c t s o f l e a c h i n g

Aerobic leaching of the Soils depressed Specific conductance and the sulphate

content, increased pH slightly, and lowered the concentration of water-soluble

iron and the partial pressure of C o z . These effects were most pronounced in soil

B and least in soil A (Table 3 , 4 , 5 ) . Leaching reduced the concentration of AI

in the soil solution from 69 ppm to 0.6 ppm in soil B and from 106 ppm to 1 1 ppm

in soil c at the start of the experiment.

E f f e c t s o f l imi l tg

Liming the air-dried soil to a pH of 5.5 before submerging increased the pH of

soil B but did not significantly effect the ultimate pH of soils A and C . Liming

brought down the concentration of Al to 0.6 ppm in soil B and to 4 ppm in soil

c. Liming lowered the concentration of water-soluble FeZ+ substantially (Table 4 )

and the SO:- concentration slightly in all three soils but increased the partial

pressure of C o z .

E f f e c t s Of !4n02

M ~ O ~ at the rate of 0.5 percent by weight of the soil depressed the concentration of water-soluble Fe2+ in all three soils but the effect was most pronounced in

soil B (Table 4 ) . MnOz did not prevent the build-up of high concentrations of

F ~ Z + and CO^ in soil C.

Growth and y i e l d o f r i c e

The responses of the rice plant to leaching, liming, and MnO2 varied as widely

as the chemical kinetics did. They were most pronounced in soil C and least in

soil A. Plant performance agreed with the chemical data.

S o i l A

Rice grew well in both the treated and untreated s o i l s . There were no symptoms

395

of salt injury, aluminium toxicity, or iron toxicity. Chemical analyses revealed

a relatively low specific conductance, a pH too high for excess water-soluble Al,

and a peak of only 184 ppm for water-soluble Fe2+ in the untreated soil (Table

3 , 4).

Acid sulphate soils like A can be made productive by the use of N and P fertili- zers and good cultural practices. They need no other amendments.

S o i l B

All plants except those in the leached soils showed leaf roll and the white disco-

loration of the upper parts of the leaf blades associated with salt injury. The

specific conductance of the unleached treatments was more than four times that

of the leached treatment (Table 3 ) . Four weeks after transplanting, a reddish

brown discoloration of the older leaves (a symptom of iron toxicity) appeared

in the control plants. Leaching, liming, and Mn02 alone or in combination preven-

ted iron toxicity. Of the single factor treatments, leaching was the best. Lea-

ching benefited rice on this s o i t because leaching virtually eliminated salt, A l ,

and CO2 injury and it reduced iron toxicity. The combination of leaching, liming,

and MnOn, however, gave the highest yield of straw and grain (Table 6).

S o i l C

Rice plants on the untreated soil suffered from all the ills of a submerged acid

sulphate soil - salt injury, Al toxicity, Fe” toxicity, and CO2 toxicity. The

yellowish streaks between the veins (symptoms of Al toxicity) and leaf roll due

to excess electrolyte were visible during the first week after transplanting.

Symptoms of Fe toxicity then appeared and became more severe with time. Within 2

weeks rice plants in all treatments that did not include liming showed symptoms

of severe Fe toxicity; the plants in the control were dead. Unlike in soil B, leaching alone was not a satisfactory amendment, while limi-ng alone was. Leaching

failed to improve the growth of rice because it did not prevent the build-up

and persistence of high concentrations of Fe2+. The chief benefits of liming were

elimination of Al toxicity and alleviation of iron toxicity. The combination of

leaching, liming, plus MnO2 gave the highest yield of grain and straw (Table 6).

Conclusions

Acid sulphate soils differ in their properties and in their chemical and electro-

chemical kinetics when submerged. These differences are reflected in the chemical

and electrochemical responses to amendments and in the growth and yield of rice.

396

The main causes of the toxicity of acid sulphate soils to lowland rice are acid

and aluminium injury at flooding and transplanting, and excess iron later. Excess electrolyte and high co? concentrations are additional growth re- tardants.

These problems

relatively high, its salt content was low, and it contained an adequate

of iron oxides which were somewhat resistant to reduction. Soil c , with its low p ~ , high content of electrolyte, and a high content of easily reducible iron

oxides, had the problems in an acute form. S O the plants in the untreated soil

died. The main problem in this soil was the build-up of high concentrations of wa-

ter-soluble iron. Neither leaching nor MnOz arrested this, although these treat-

ments were effective in soil E, with its low content of iron.

The combined treatment (leaching plus liming PIUS MnO?) gave the highest yield

of grain on all three soils, but leaching plus liming came a close second. Lea-

ching alone may suffice on soil E; liming alone, on soil C .

The p ~ , salt content, and the content and reactivity of iron are important para-

meters in the assessment of the suitability of acid sulphate soils for lowland

rice.

weeks

were Virtually absent in Soil A because the pH of the soil was

397

--

I I \

\ \

\

\ \ I

\

o0 I

\ \

w O

o \ ‘\ ,j

m I I I I I I i I I I I

I I

TABLE 1.

CHEMICAL ANALYSES OF THREE ACID SULPHATE SOILS

pH ( 1 : I water)

Specific conductance (mmhoslcm)

Carbon (%)

Nitrogen (2)

Cation exchange capacity (meq.1100 g.)

Exchangeable bases (meq.1100 g.)

Exchangeable and water-soluble SO:- (ppm S )

Water-soluble Al (ppm)

Active Fe- ( X ) ++)

Active Mn- (ppm) ++)

Available P (Olsen) %

Exchangeable K+ (meq.1100 g.)

Available Zn- (ppm) +++I

A

4 . 3

I .3

1.7

O . 17

~

3 0 . I

1 7 . 8

681

0 . 6

1 . 1

6 0

5 . 4

0 . 5 7

3 . 3

B

3.6

8.3

5.6 0 . 2 7

~

2 3 . 0

8 . 1

2083

6 9

0.08

5

4 . 0

0 . 0 4

I .4

+) A: an old (ripe) catclay of the Ongkharak Series (Thailand)

B: a cat-clay of the Long-My Series (Vietnam)

C: a mud-clay from a paddy field, Sariaya, Luzon, Philippines

++) By the method of Asami and Kumada ( 4 )

By the method of Treiweiler and Lindsay ( 3 1 ) +++)

C+) -~ 3 .4

4.9

3 . 3

O . 18

3 0 . 3

12.3

2479

106

1.9

4 0 0

5 8

0 . 0 4

6 . 1

TABLE 2 . COMPARISON OF THE APPARENT STANDARD FREE ENERGIES OF FORMATION OF DIFFERENT SPECIES OF Fe(OH), AND Fe3 (OH)

- 1 6 9 . 5 -462.1

-170.7 -466 .2

- 1 6 5 . 9 - 4 5 1 . 7

- 1 6 5 . 8 - 4 5 1 . 3

- 1 6 6 . 0 ++)

-45 1 .2 +++)

+)

++) Reference ( 1 4 )

Reference ( 2 4 )

Reddish brown clay (PH 4 . 6 ; O.M. 3.2%; active Fe 2 . 8 % )

+++)

4 O0

TABLE 3 .

INFLUENCE OF LEACHING AND LIMING ON THE KINETICS OF SPECIFIC CONDUCTANCE IN

THREE SUBMERGED ACID SULPHATE SOILS

TREATMENT

Weeks submerged

O 2 4 6 8 10

Specific conductance (mhoslcm at 25'c)

Soil A Untreated

Le ach e d

Limed

Soil B Untreated

Leached

Limed

Soil C Untreated

Le ach e d

Limed

3.1 3 .0 2 . 9 3 . 1 2.7 2 . 0

1 . 1 1 . 5 1 . 4 1 . 2 0 . 9 0 . 8

3.5 3 . 2 3 . 0 2.9 2 . 5 1 . 8

5 .4 1 0 . 4 1 0 . 3 9 .4 10.6 9 . 8

1 . 3 1.6 2 .1 2 .4 2 . 6 2 . 6

6 . 6 10.2 1 1 . 3 10.1 10.2 9.9

6 .5 8 . 4 10.5 9 . 2 8 . 8 8 . 7

1.0 3 . 5 5 . 0 4 . 4 4 . 2 3 . 8

4.1 6 . 4 6 . 5 5 . 4 5 . 5 5 . 4

TABLE 4 .

INFLUENCE OF LEACHING, LIMING, AND Mn02 ADDITION ON THE KINETICS OF WATER-

SOLUBLE Fe2+ IN THREE SUBMERGED ACID SULPHATE SOILS

Weeks submerged

TREATMENT O 2 4 6 8

Water-soluble Fe2+ (ppm)

.- I O

Soil A Untreated

Leached

Limed

MnOl added

Soil B

Untreated

Leached

Limed

MnOz added

soil C Untreated

Leached

Limed

MnOl added

0 . 4

0.0

0.1

0 . 4

I .7

2 . 7

2.7

2 . 6

107

1 .O

2 . 5

19

114

5 0

86

I 0 5

5 4 3

35

I 5 8

20

3455

745

I 3 0 4

3085

160

7 6

I 3 0

146

765

I 3 0

326

7 0

4060

I 7 8 3

1055

3440

184

38

I I 5

I 5 6

915

299

340

200

2794

I 1 7 4

609

2902

I 4 6

17

47

114

873

386

296

76

2591

1141

59 1

2133

122

34

57

I 2 4

860

426

196

30

2400

1200

558

1866

40 1

P

TABLE 5 .

INFLUENCE O F L E A C H I N G , L I M I N G , AND MnO2 A D D I T I O N ON THE K I N E T I C S O F P

I N TWO SUBMERGED A C I D SULPHATE S O I L S c02

Weeks s u b m e r g e d -~ ~ -~

TREATMENT O 2 4 6 8 10

pco2 ( a t m ) _ _ _ _ ~

S o i l B

U n t r e a t e d

L e a c h e d

L i m e d

MnOz added

S o i l C

U n t r e a t e d

L e ach e d

L i m e d

M n 0 2 added

0 . 0 3 0 . 3 8 0 . 4 2 0 . 4 0 0.21 0 . 1 5

0 . 0 2 0.11 0.17 0 . 2 2 0 . 1 6 0 . 1 6

0 . 3 7 0 . 6 6 0 . 6 6 0 . 6 2 0 . 2 4 0 . 1 8

0 . 1 7 0 . 3 5 0 . 3 5 0 . 2 6 0.15 0 . 1 6

0 . 0 4 0 . 7 7 0 . 8 4 0 . 7 5 0 . 7 4 0 . 7 2

0 . 0 3 0 . 6 1 0 . 7 2 0 . 7 3 0 . 7 5 0 . 6 7

0 . 6 3 0 . 7 9 0 . 7 2 0 . 6 8 0 . 6 1 0 . 3 3

0 . 0 3 0 . 7 4 0 . 7 1 0.71 0.71 0 . 7 2

TABLE 6 .

INFLUENCE OF L E A C H I N G , L I M I N G , AND M n 0 2 A D D I T I O N ON THE Y I E L D O F R I C E ON TWO

FLOODED A C I D SULPHATE S O I L S

TREATMENT

Y I E L D (g / p o t ) ~.

S O I L B SOIL C

G r a i n S t r a w G r a i n S t r a w

C o n t r o l

MnOp ( 0 . 5 % )

L i m e d to pH 5 . 5

L i m e d + MnO2

L e a c h e d

L e a c h e d + MnOL

L e a c h e d + L i m e d

L e a c h e d + L i m e d + MnOp

21

6 2

6 4

7 2

7 8

91

8 8

I 0 3

24

6 4

6 4

67

7 5

8 2

7 8

9 5

O 0

7 12

7 9 76

84 7 5

I 1 20

5 0 59

8 3 8 2

9 2 104

402

REFERENCES

(I) American Public Health Association 1971. Standard Methods for the ~ ~ ~ ~ i - nation of Water and Wastewater. 13th ed. Washington D.C.

(2) ARDEN, T . V . 1950. The solubility product of ferrous and ferrosic hydroxide.

J.Chem.Soc.1950: 882-885.

(3) ARNON, D . I . , JOHNSON, C.M. 1942. Influence of hydrogen ion concentration on

the growth of higher plants under controlled conditions. Plant physiol.

17: 525-539.

(4) ASAMI, T., KUMADA, K. 1959. Comparison O f Several methods of determining

free iron in soils. Soil Sci. P1.Nutr. 5: 179-183.

(5) AURIOL, P.F., LAM-VAN-VANG. 1934. Etudes sur les terres et les eaux alu-

&es. Bull.Econ. de l'hdochine, Hanoi.

(6) CATE, R.B,Jr., SUKHAI, A.P. 1964. A study of aluminum in rice soils. soil

Sci. 98: 85-93.

(7) CHENERY, E.M. 1954. Acid sulphate s o i l s in Central Africa. Trans.5th

Intern.Congr.Soi1 Sci. Léopoldville. 4:195-198.

International Rice Research Institute 1965. Annual Report for 1964. Los

Banos, Philippines.

International Rice Research Institute 1968. Annual Report for 1967. LOS

Bacos, Philippines.

( 8 )

(9)

(]o) JORDAN, H.D. 1963. Development of mangrove swamp areas in Sierra Leone.

Agron.Tropicale 18:798-799.

(I]) WPRATH, E.J. 1967. Soil acidity and response to liming. Intern. Soil

Testing. Tech.Bull.No.4.

( 1 2 ) UWAGUCHI, K., KYUMA, K. 1969. Lowland Rice Soils of Thailand. Center for

Southeast Asian Studies. Kyoto University. 270 p.

(13) KOBAYASHI, T., SAKURAI, T., SATO, Y. 1953. Some chemical characteristics of

the strong acid soils found on the restored lands in Chikuko coal mine field. Kyushu Agr.Exp.Sta.Bull.2:81-96.

(14) LATIMER, W . M . 1952. Oxidation Potentials. 2nd ed. Prentice-Hall, Englewood

Cliffs, New Jersey.

403

i

F

(15) MOOFXANN, F.R. 1963. Acid sulphate soils of the tropics. Soil Sci.95:

27 1-280.

(16) MURAKAMI, H. 1969. Distribution and improvement of acid sulphate soils in

Japan. Japan Agric.Res.Quarter1y 4:50-53.

(17) NHUNG, Mai-Thi My, PONNAMPERUMA, F.N. 1966. Effects of calcium carbonate,

manganese dioxide, ferric hydroxide, and prolonged flooding on chemical and

electrochemical changes and growth of rice in a flooded acid sulphate soil. Soil Sci. 102:29-41.

(18) OKUDA, A. 1952. Plant Nutrition and Fertilizers. Zokendo, Tokyo. In japa- nese.

(19) PHAM-HUU-ANH, MOORMANN, F.R., GOLDEN, H.D. 1961. Liming experiments on

acid sulphate soils. In: Researches on Acid Sulphate Soils and Their Ameli-

oration. Ministry of Rural Affairs, Saigon.

(20) PONNAMPERUMA, F.N. 1965. Dynamic aspects of flooded soils and the nutrition

of the rice plant. In: Proceedings Symposium on the Mineral Nutrition of

the Rice plant. 1964. pp.295-328. John Hopkins Press, Baltimore.

(21 ) PONNAMPERUMA, F.N. 1971. Oxidation-Reduction Reactions. In: Chemistry of

the Soil. 3.M.Bremner and G.Chesters (eds.). Dekker, New York. In press.

(22) PONNAMPERUMA, F.N. 1972. The Chemistry of Submerged Soils. Adv.Agron.24.

In press.

(23) PONNAMPERUMA, F.N., BRADFIELD, R., PEECH, M. 1955. A physiological disorder

of rice attributable to iron toxicity. Nature 175: 265.

(24) PONNAMPERUMA, F.N. , TIANCO, E . M . , LOY, T. 1967. Redox equilibria in flooded

soils. I. The iron hydroxide systems. Soil Sci.103:374-382.

(25) PONS, L.J., KEVIE, W.van der. 1969. Acid sulphate soils in Thailand. Rept.

SSR-81-1969. Soil Survey Div.Bangkok. p.69.

(26) RAUPACH, M. 1963. Solubility of simple aluminium compounds expected in soil. Austral.J.Soi1 Res.l:28-62.

( 2 7 ) TANAKA, A., NAVASERO, S . A . 1966. Growth of the rice plant on acid sulphate s o i l s . Soil Sci.Pl.Nutr.12:23-30.

(28) TANAKA, A., NAVASERO, S.A. 1966. Interaction between iron and manganese in

the rice plant. Soil Sci.Pl.Nutr.12:197-201.

404

P I

(29) TANAKA, A., NAVASERO, S.A. 1967. Carbon dioxide and organic acids in rela-

tion to the growth of rice. S o i l Sci.Plant Nutr. 13:25-30.

(30) TOML,INSON, T.E. 1957. Changes i n a sulphide-containing mangrove soil on

drying and their effect upon the suitability of the soil for the growth

of rice. Emp.J.Exp.Agric.25:108-118.

(31) TREIwEILER, J . F . , LINDSAY, W.L. 1969. EDTA-ammonium carbonate soil test for zinc. soil Sci.Soc.Amer.Proc. 33:49-53.

(32) WILSMW, R.G.H. 1940. Note on the development of high acidity in certain

coastal clay soils of Malaya. Malaysian Agric.J.28:352-357.

405

Smmary

In a greenhouse experiment w i th three acid sulphate soils t he authors s tudied the inf luence of leaching, liming and adding &O, on the chemical k i n e t i c s of t he flooded s o i l and on the growth o f r i c e . The m e l i o r a t i n g e f f e c t of t he treatments, s ing le o r in combination varies w i th d i f f e rences in pH, s a l i n i t y and r e a c t i v i t y o f i r o n f o r each of the soils.

Résumé

Dans une expérience en vases avec t r o i s sols sulfate's acides on a étudie' l ' e f f e t du less ivage, du chaulage e t de Z'apport de ?4?'202 sur l a c inét ique chimique des so ls inondés e t l a croissance du riz. L ' e f f e t me' l iorant des trai tements , apart

on combings, varie avee des d i f f e rences en p H , s a l i n i t é e t réact iui te ' du f e r dans

l e s sols.

Reswnen

En un experimiento de potes con t r e s t i p o s de suelos de su l fa tos áeidos, se ha estudiado l a i n f luenc ia de l a Z i x i ~ i a c i ó n y de l a apl icación de cal y de M n O z

sobre Za quimica c iné t i ca de los suelos regados y sobre e l crecimiento del arroz. E l e f e c t o mejorador de los tratamientos, d i s t i n t o s o en combinación, varia según

las di férencias en pH, salinidad y react iv idad d e l hierro en eada t i p o de suelo.

Zusmmen fassung

I n einem Gefässversuch m i t d re i versehiedenen Typen der sehwefelsauren Böden wurde d i e Wirkung der Auswaschung, Bekalkung und des Mn02 auf die chemische Kinetik der

überschwemmten BBden und auf das Wachstm der Reispflanzen geprü f t . Der Erfolg

der einze lnen oder kombinierten Behandlungen i s t von pH, S a l z h a l t i g k e i t und Eisen-

r e a k t i v i t ä t der e inzelnen Bodentypen abhüngig.

406