Effects of Desertification on the Productivity of the ...€¦ · 1 Effects of Desertification on...
Transcript of Effects of Desertification on the Productivity of the ...€¦ · 1 Effects of Desertification on...
1
Effects of Desertification on the Productivity of the Natural
and Agro-ecosystems: Consequences and Solutions
Convention to combat
desertificationLand degradation
Climatic changesHuman activities
Agro-ecosystems
Wind and water erosion
SalinizationWaterlogging
Drylands
Hyper-aridAridSemi-arid
2
5034
Sand dune encroachment
Humid environments
Deforestation
Unproductive deserts 9
80
Waterlogged
11.5
Carbon
sequestration
Arable lands
Highly variable rainfall
Scarcity of water resources
Agricultural intensification
1
Wild firesOvergrazing
3
2
HeatDroughtSalinity
Abiotic factors
1
Root systems
Source size
Transpiration
Evaporation
Well-branched deep root system
4
Turgor potential
2
Protective systems
Photoinhibition
3 WUE
Capacity types
Grain fill
Photo-assimilates
4
End- product effect
CO2-enrichment
5
1971
5
1
27Wheat42 Barley
Water use efficient cultivars
Water
productivity
EvaporationProductive transpiration loss
Contour ridging
Mulch
6
1
65
65
1 59
65
60
60
60
357 107 885 2 68
68
1103
1103
2 899
176
176
176
176
1105 1 901 4 1230
1107 1107 969
1164
1169 5 1119 2 1420
7
1119 1 1097 1 1500
1229 3 981
1245
1069
Intensive marginal
agricultural systemsRangeland areas
Technically feasible
Socially acceptableSustainable
Reverse
2
9
offDeep drainage Evaporation
Transpiration
Weeds
Soil moisture content
Capture
Water
infiltration
1
2 Reseeding degraded rangelands
3 Fodder shrubs and trees
4
Pits
10
Degraded calcareous soils
Seedling establishment
Wind erosion
Intensive fallow system
Cereal monocropping
Soil fertility
Wind erosion
Vetches
(Vicia spp.)(Lathyrus spp.) Chcklings
Mediterranean
basin
Hay
Straw
Small ruminant flocks
Crop residues
11
CO2Intensive tillage
3050
Sustainable land productivityTillage
Carbon sequestration
1998Paustian et al.,
400900MMTCE
1997Lal15
(SOC) Soil organic carbon
200 MMTCE
Soil erosion
Soil Temperature regulation
12
No-tillage
Lal, 1997; Paustian et al., 1997b
CO2-sequestration
Yield gapFood gap
1Wheat
Conservation agriculture1136.55
11087.55
1
10.04
2Rainwater use efficiency
4.261
3.141
13
1
2
39251
3290
1350
1400
1450
1500
1550
1600
1650
الزراعة الحافظة الزراعةالتقليدية
ة جي
تاإلن
اطس
توه
(غك
/ار
كته
)
نظام الزراعة
الزراعة الحافظة الزراعة التقليدية
Series1 4.26 3.14
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
ر طا
لواال
ه يا ه
العو
ست اءة
فاك
(غك
/(هن
14
.1
18.723
3
4
4
الزراعة الحافظة الزراعة التقليدية
Series1 3925 3290
2800
3000
3200
3400
3600
3800
4000
ر عي
ش ال
يةجتاإنط
ستو
ه(
غك
/ار
كته
)
02468
10
الزراعة الحافظة الزراعة التقليدية
Series1 9.2 7.48
ر طا
لو ال
اههي
ل وا
تعس
اءة
فاك
(غك
/(هن
15
Evaporation
Organic matter
Aggregate size and stabilitySoil porosity
11051
Seed dressing
N 9% + P 15%
18Zn+2
6Cu+2
27.4Mn+2
5
Seeding rate
6912
1Weed control
Weeds
11051121
16
405.211
61
214.201
5.52
10.19
12112.94
Evaporation
More crop per drop
Water harvesting and irrigated agriculture:
Cisterns
17
Micro-
catchment techniques
Artificial storage structures
Macro-catchment techniques
Supplemental irrigation
Topography
Run-off coefficient
Shallow aquifers
Water
extractionRecharge
Sea water intrusion
19
References
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Dubai. Taylor & Francis. 489 pages.
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Vision. ICARDA-023/400. PP.1-20.
FAO. 1995. FAO STAT. PC. FAO, Rome, Italy.
Farouk El-Baz and M.H.A.Hassan. 1986. Physics of desertification.
International Centre for Theoretical Physics. Springer. 473 pages
Glantz, M. H., and N. S. Orlovsky. 1983. Desertification: A review of
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http://www.ciesin.org/docs/002-479/002-479.html.
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m Last modified in 2006.
http://www.greenfacts.org/en/desertification/l-2/6-prevention-
desertification.htm#3.
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Working Group III: Mitigation of Climate Change: Chapter 8:
Agriculture".
Millenium Ecosystem Assessment. 2005. Ecosystems and Human
Well-being: Desertification Synthesis: Key Questions on
Desertification in the Millennium Ecosystem Assessment. Topic
editor: Ed.-in-chief, Cutler Cleveland. Encyclopedia of Earth.
National Council for Science and the Environment. Washington DC
Nichola Geeson, C.Jane Brandt and John B.Thornes. 2002.
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John Wiley and Sons. 440 pages.
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ICARDA, Aleppo, SYRIA.
Oweis, T. 1997. Supplemental irrigation--a highly efficient water-use practice.
ICARDA-037/1000. PP.1-16.
20
Rodriguez, A. 1997. Poverty and natural resources management in dry areas.
UN Food and Agriculture Organization. "The World's
Drylands". http://www.fao.org/docrep/007/y5738e/y5738e06.htm
Accessed 08 June 2010.
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