Sustainable AgroForestry in Degraded Drylands

8/4/2019 Sustainable AgroForestry in Degraded Drylands

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Sustainable Agroforestry in

Degraded Drylands:

Win ± Win Approaches for Local,Regional and Global Problems

Leu S. and Mor-Mussery A.in collaboration with the Sustainability Laboratory



Overexploitation Land Degradation by

-Productivity

-Carbon Stocks

-Biodiversity-Resilience and Sustainability Mismanagement

Acceleration of and Sensitization to Effects of Global Warming



2. Rehabilitation by Restoration of Vegetation

Productivity +

Carbon Stocks +

Biodiversity +Resilience and Sustainability + Management

Mitigation of and Adaptation to Effects of Global Warming!



Engineering or Forestry

Topography Analysis and Engineering Requirements

N



Site plan

Riverine,

native plants

*Plants the

will be suited

in the edges of the river

Silvipasture

Savanna

trees with

additional

uses

(mainly

pasture),

suited to

arid zones,

Shade

trees

The shade

pathways

Fenced Green

Tree

To border between

the different fieldsand supplement

extra use (crop,

pasture, shade

etc«)



� The area excluded by the black line is unsuitable for large agricultural plots, while areas 1

± 4 do not pose any problems except for small corrections along the river;

� The following pictures demonstrate these facts;



200m

Only the two marked rhomboids are suitable

for agriculture, about 10 and 5 dunam;

Stable

Wadi

Unstable

Wadi

and Soil

Large Rocky Slope with Wadis



The Soil in the southern-most Wadi is highly erosive;

these erosion structures have to be stabilized by terraces, planting of

mixed trees, olive plantations and high value trees;

Native trees will be incorporated for high grazing value, biodiversity and

agricultural return;



: Restoration of vegetation, erosion control and tree1Technique

planting using contour drip irrigation

Trees and Shrubs were planted along drip

irrigation, every 2m one line was established,and every dripper received 100L of water

during November-December 2008.



The number of functions fulfilled by dryland trees is huge

�Carbon Sequestration into biomass;

� Recovery of nutrients from deep soil;

� Enrichment and protection of top soils by plant litter;

� Increasing productivity of annual vegetation;

� Preventing wind erosion;

� Providing shade to animals and buildings;

� Preventing water runoff and erosion;

� Restoring natural habitats and biodiversity;

� Providing fodder during the dry season;

� Providing biomass energy;

� Providing high value oils and fruit for economic expansion;

Technique2: Restoration of land using dryland trees



20 years old Acacia victoria woodland near

Yattir farm (220 mm mean AnnualPrecipitation)

2.5 t per ha and year annual vegetation;2.5 tons per ha and year tree litter (edible);

1 ton per ha and year woody biomass;

6 tons per year CO2 sequestration;Supports 2 goats per ha:

RICH ANIMAL LIFEDegraded land nearby:

0.5 t per ha and year annual vegetation

NO tree litter!

NO woody biomass!

NO CO2 sequestration!

Supports 0.2 goats per ha

NEGLIGIBLE ANIMAL LIFE!!!

*Problem: Acacia victoria is not a native species!

Fact: Woodland trees Sequestrate high Carbon amounts into biomass



Biomass, slope trees

0

5

10

15

20

25

30

35

40

45

Total Litter Weeds

g p e r 6 0 0 c m ^

canopy

open

Facts: Grazing Improvement, Land Rehabilitation and

Biomass Production by Silvipasture

Biomass and Litter under TreeCanopy and in nearby Open

Areas:

Suitable Trees Promote Growth

of Annual Vegetation and

Provide Extraordinary Amountsof Organic Litter!



Facts: Using trees for agriculture purposes in arid

environments

Left: niche of wheat growing without need of irrigation and nutrient

supply;

Right: Small olive tree survives inside the Acacia victoria woodland,

taking advantage of higher soil fertility and humidity, reduced

evaporation and protection from wind by the other trees.



planting techniques:

The planting method dramatically affects soil characteristics

Contour Trenching Planting without Soil Disturbance

0

0 5

1

1 5

2

2 5

3

Savanna Open C ntour Open Savanna Canopy Contour Canopy

S O C ( %

)



Terrace Agroforestry using Natural Topography

A simple stone terrace suffices to create excellent conditions for Olive

cultivation. The reduced water runoff intensity allows natural vegetation

to recover as well.



Intercropping in Agroforestry Terraces

Other Crops Used for

Intercropping:

� Vegetables

� Watermelons

� Sunflowers

� Tobacco

Classical agroforestry with summer sorghum (left behind) intercropped with

olive trees. The humidity stored in the soil of the dammed areas suffices to

maintain growth of sorghum throughout the hot, completely dry summer.



An area covered by manure (right) displayed very significant plant

growth in spite of very poor rainfall (~110 mm in 2009), in contrast to the

exposed soil to the left.

Principle of Soil Management:

THE MOST IMPORTANT:

Exposed Soil Degradation



Expected Benefits at Wadi Attir

� Carbon sequestration compensating for theagricultural greenhouse gas emissions.

� Water savings by optimized agricultural production,wind breaks, plant litter and no till agriculture;

� Reduced fertilizer use due to nitrogen fixing plantsand nutrient recovery from deep soil by trees;

� Improved biodiversity due to planted native trees;

� Increased profitability due to growing amounts of high quality high price oils;

� Providing waste biomass for energy production fromtree trimming;

� Reduced erosion and soil loss due to terraceagroforestry and erosion barriers;

Documents

Sustainable AgroForestry in Degraded Drylands