10 GENERAL LAND CAPABILITY

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1 10 GENERAL LAND CAPABILITY

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3 RESULTS AND DISCUSSION Land capability has been studied in for different climatic scenarios and crops, and in El-Fayoum depression under different scenarios of irrigation management and crops. In order to make the best use of land and to minimize the potential negative impacts, land capability analysis is essential (Singer, 2002). Cervatana model, as other land-capability classification systems, aggregates soil map units into groups with similar responses to management, hazards, limitations or risks (Klingebiel and Montgomery 1961) LAND CAPABILITY OF ANDALUSIA UNDER CLIMATE CHANGE SCENARIOS Land capability in has been evaluated under the current climate scenario (average data between 1960 and 2000) and projected climate scenarios (2040, 2070 and 2100) for two major rainfed crops (wheat and sunflower) and three other crops (potato, maize, and cotton). The irrigated zones in the study area represent around 10% of the total area of. Land capability analysis has been carried out based on climatic parameters as precipitation and temperature, and not considering any irrigation water inputs. Assessment of land capability has also been applied to forest soils, which cover 41.8% of the total study area. Classification of forest areas ranged from S3tr to Ntl. The most limiting factors are topography, shallow soil depth, and high erosion risk in the different soil types. Some soils, though, are used for forest but have a good land capability class as JA06-. Cervatana outputs show that land capability of large areas of, especially under maize and cotton crops, is classified as moderate and marginal, Nevertheless, this evaluation has not considered the potential impact of irrigation water and, in practice, capability of moderate and marginal lands may be considerably improved under irrigation LAND CAPABILITY UNDER WHEAT CROP Under wheat cultivation, the assessment of land capability ranged from S2r and S2l (good; CA02-Chromic Haploxererts, CO07-Typic Xerofluvents and SE08-Aquic Haploxeralfs), to Ntl (not suitable; GR04-Lithic Haploxerepts). As shown in Table 10-1, 7.6 % of the study area has a good capability class with only one limiting factor. Currently, 14.2% of the area has a good class with limiting factors, but this is expected to increase slightly (to 16.4%) under the projected climate 207

4 CHAPTER 10 scenarios (2040, 2070 and 2100). Land capability assessment showed that 19.1% of the area is classified as a marginal soil and this percentage does not change under the different climate change scenarios (Table 10-1 and Figure 10-1). In most cases, land capability class is not expected to change under future climate scenarios, except for some soil types that are located in GR01, HU02 and JA01 units. In these regions, slight negative impacts at subclass level are expected, especially under the 2040 scenario. Figure 10-1 shows the temporal and spatial projections of land capability. Table Total area ( 2 and %) suitable for wheat crop in under different climate situations: current situation and future projections (2040, 2070, 2100) according to the Cervatana model. S2: good, S3: moderate, N: not suitable. The number of limiting factors for each class is shown in parentheses. Land capability classes % 2 % 2 % 2 % S2(1) S2(2) S2(3) S2(4) S3(1) S3(2) S3(3) S3(4) N(1) N(2) N(3)

5 TPXA TDUI XHCR S2 l,r S2 lr S2 tlr,lrb TDUI AXFE N t,l N tl XHCR CORRECT_SOIL_MAP _W UR_2 S3 t,l,r S3 tr,lt S3 tlr S3 l,r,t S3 lr,tr S3 tlr N l,t N tl S2 l,r S2 lr S2 lrb,tlr AXFE AHXA CHXA Climate scenario 2070 TPXA HUAE 60 0,: ,:1 4 AHXA CHXA HUAE Current climate scenario TPXA XHCR TDUI AXFE XHCR S3 l,r,t S3 lr,tr S3 tlr N t,l N tl S2 l,r S2 lr S2 lrb,tlr TDUI Climate scenario 2100 AXFE S2 r S3 l,r,t N t,l S2 lb,lr S3 lb,lr,tl,tr N tl S2 lrb,tlr S3 tlr AHXA CHXA TPXA HUAE AHXA CHXA HUAE 0,:4 1 Climate scenario 2040 RESULTS AND DISCUSSION Figure Land capability for wheat cropping in. Limitation factors; t, topography (slope type and slope gradient); l, soil (useful depth, texture, stoniness/rockiness, drainage, and salinity); r, erosion risk (soil erodibility, slope, vegetation cover, and rainfall erosivity); b, bioclimatic limitation. 209

6 CHAPTER LAND CAPABILITY UNDER SUNFLOWER CROP For sunflower crop, soil units CA03-, HU05-, JA01-, SE01-CHXA, SE02-, SE09- and CA02- currently have a good land-capability subclass (S2lr) but it is expected to decrease to S2lrb under climatic scenarios 2040, 2070 and GR05- is currently classified as S2lr and is projected to remain S2lr under climate scenarios for 2040 and 2070, but is expected to change to S3b under the 2100 scenario. On the other side, extreme changes in land capability for sunflower cropping is observed in the soil unit AL02-, where the assessment of land capability is currently S3lrb (moderate) but will likely change to Nb (marginal) in the future climate scenarios. In addition, land capability of AL08- is currently S2lrb (good) but is expected to change to S3b (moderate) under the 2040 and 2070 climatic scenarios, and Nb (marginal) under the 2100 scenario. Table 10-2 shows detailed information about the area corresponding to the different land capability classes and subclasses, and how it changes between the current situation and the future climate scenarios (2040, 2070 and 2100). Figure 10-2 shows a detailed temporal and spatial analysis of land capability under sunflower cultivation. Table Total area ( 2 and %) suitable for sunflower crop in under different climate situations: current situation and future projections (2040, 2070, 2100) according to the Cervatana model. S2: good, S3: moderate, N: not suitable. The number of limiting factors for each class is shown in parentheses. Land capability classes % 2 % 2 % 2 % S2(1) S2(2) S2(3) S2(4) S3(1) S3(2) S3(3) S3(4) N(1) N(2)

7 TPXA TDUI XHCR S2 l,r S2 lr S2 tlr,lrb TDUI AXFE N t,l N tl XHCR CORRE CT_SO IL_M AP_W UR_2 S3 t,l,r S3 tr,lt S3 tlr S3 l,r,t S3 lr,tr S3 tlr N l,t N tl S2 l,r S2 lr S2 lrb,tlr AXFE AHXA CHXA Climate scenario 2070 TPXA HUAE 60 0,: ,:4 1 AHXA CHXA HUAE Current climate scenario TPXA XHCR TDUI AXFE XHCR S3 l,r,t S3 lr,tr S3 tlr N t,l N tl S2 l,r S2 lr S2 lrb,tlr TDUI Climate scenario 2100 AHXA CHXA S2 r S3 l,r,t N t,l S2 lb,lr S3 lb,lr,tl,tr N tl S2 lrb,tlr S3 tlr AXFE TPXA HUAE AHXA CHXA HUAE 0,:4 1 Climate scenario 2040 RESULTS AND DISCUSSION Figure Land capability for sunflower in. Limitation factors; t, topography (slope type and slope gradient); l, soil (useful depth, texture, stoniness/rockiness, drainage, and salinity); r, erosion risk (soil erodibility, slope, vegetation cover, and rainfall erosivity); b, bioclimatic limitation. 211

8 CHAPTER LAND CAPABILITY UNDER POTATO CROP Land capability assessment for potato cultivation ranged from S2rl (good) to Ntl (marginal). Under climate change scenarios, small negative changes occurred in land capability, compared to the current situation. GR04- soil type has the worst land capability class (Ntl) and soils CA02-, CO07-, SE08-AHXA have good capability (S2r), when compared to the other soil types. Capability of AL08- soil unit is S2lr (current and 2040 scenarios), but it changes to S2lrb (scenario 2070), and S3b (scenario 2100). The area of marginal land increases slightly from 19.1% (current scenario) to 20.3% (2100). Table 10-3 shows the size of the different land capability classes under current and future climate scenario. Figure 10-3 shows a detailed temporal and spatial analysis of land capability under potato cultivation. Table Total area ( 2 and %) suitable for potato crop in under different climate situations: current situation and future projections (2040, 2070, 2100) according to the Cervatana model. S2: good, S3: moderate, N: not suitable. The number of limiting factors for each class is shown in parentheses. Land capability classes % 2 % 2 % 2 % S2(1) S2(2) S2(3) S3(1) S3(2) S3(3) N(1) N(2)

9 RESULTS AND DISCUSSION Current climate scenario HUAE AHXA TPXA CHXA AXFE XHCR TDUI S2 l,r S2 lr S2 lrb,tlr S3 t,l,r S3 tl,tr,lr S3 tlr N t,l N tl Climate scenario 2070 AHXA CHXA HUAE TPXA AXFE XHCR TDUI S2 l,r S2 lr S2 lrb,tlr S3 t,l,r S3 tl,tr,lr S3 tlr,lrb N t,l N tl Climate scenario 2040 HUAE AHXA TPXA CHXA AXFE XHCR TDUI S2 r S2 lr,lb S2 lrb,tlr S3 t,l,r S3 tl,tr,lr S3 tlr N t,l N tl Climate scenario 2100 HUAE AHXA TPXA CHXA AXFE XHCR TDUI S2 l,r S2 lr S2 lrb,tlr S3 t,l,r,b S3 tl,tr,lr S3 tlr N t,l,b N tl Figure Land capability for potato in. Limitation factors; t, topography (slope type and slope gradient); l, soil (useful depth, texture, stoniness/rockiness, drainage, and salinity); r, erosion risk (soil erodibility, slope, vegetation cover, and rainfall erosivity); b, bioclimatic limitation. 213

10 CHAPTER LAND CAPABILITY UNDER MAIZE CROP The land capability analysis under maize cultivation ranges from a good (S2l) to marginal (Ntlb). Bioclimatic limitations appear to be a limiting factor for land capability, especially under the projected scenarios (2040, 2070 and 2100), especially for units GR07-, HU03-, MA04- and AL06-XHCR. The total area with marginal land capability class reaches 48 % of the study area, while good class covers just 6.2% under the climate scenario 2100 (Table 10-4). Figure 10-4 shows the detailed spatial and temporal analysis of land capability under maize crop, and also shows how marginal areas (N) increase sharply under the studied climate scenarios 2070 and Climate change scenarios clearly have the most negative impact on land capability for maize compared to the rest of studied crops. Table Total area ( 2 and %) suitable for maize crop in under different climate situations: current situation and future projections (2040, 2070, 2100) according to the Cervatana model. S2: Good, S3: moderate, N: not suitable. The number of limiting factors for each class is shown in parentheses. Land capability classes % 2 % 2 % 2 % S2(1) S2(2) S2(3) S2(4) S3(1) S3(2) S3(3) S3(4) N(1) N(2) N(3)

11 RESULTS AND DISCUSSION Current climate scenario AHXA CHXA HUAE TPXA AXFE XHCR TDUI S2 l,r S2 lr,rb S2 lrb,tlr S2 tlrb S3 t,l,r,b S3 tl,tr,tb,lr,lb,rb S3 tlr,lrb N t,l,b N tl,lb Climate scenario 2070 AHXA CHXA HUAE TPXA AXFE XHCR TDUI S2 l S2 lrb S2 tlrb S3 l,r,b S3 tb,tr,lr,lb S3 tlr,tlb,trb,lrb S3 tlrb N t,l,b N tb,lb N tlb Climate scenario 2040 AHXA CHXA HUAE TPXA AXFE XHCR TDUI S2 lb,rb S2 lrb S2 tlrb S3 t,l,r,b S3 tb,tr,lr,lb,rb S3 tlr,tlb,trb,lrb N t,l,b N lb N tlb Climate scenario 2100 HUAE AHXA TPXA CHXA AXFE XHCR TDUI S2 l S2 lrb S3 l,r,b S3 tb,tr,lr,lb S3 tlb,trb,lrb S3 tlrb N t,l,b N tb,lb N tlb Figure Land capability for maize cropping in. Limitation factors; t, topography (slope type and slope gradient); l, soil (useful depth, texture, stoniness/rockiness, drainage, and salinity); r, erosion risk (soil erodibility, slope, vegetation cover, and rainfall erosivity); b, bioclimatic limitation. 215

12 CHAPTER LAND CAPABILITY UNDER COTTON CROP Land capability for cotton indicated that the classification ranged from good (S2lb or S2rb, for example in CO07-) to marginal (Ntlb in GR04-, for example). The cotton crop ranks second after maize among the crops most severely affected by climate change. Capability of some soil types changes from moderate to marginal as, for example, AL05-, AL07- and SE05-, especially under scenario Table 10-5 shows the different areas of land capability classes under the studied scenarios of climate change, and Figure 10-5 shows a detailed spatial and temporal analysis of land capability under cotton vegetation. The good class (S2) of land capability currently represents 14.7 % of the total studied area but only 6.2 % under climatic scenarios 2070 and Currently, marginal class (N) covers 21.2% of, but it is expected to expand to 32.4 % in The more distant projected climate scenarios (2070 and 2100) have the most extreme impact of climate change when compared to the current situation and the 2040 scenario. Table Total area ( 2 and %) suitable for cotton crop in under different climate situations: current situation and future projections (2040, 2070, 2100) according to the Cervatana model. S2: good, S3: moderate, N: not suitable. The number of limiting factors for each class is shown in parentheses. Land capability classes % 2 % 2 % 2 % S2(2) S2(3) S2(4) S3(1) S3(2) S3(3) S3(4) N(1) N(2) N(3)

13 RESULTS AND DISCUSSION Current climate scenario HUAE AHXA TPXA CHXA AXFE XHCR TDUI S2 lb,rb S2 lrb,tlr S3 t,l,r,b S3 tr,tb,lb,lr,rb S3 tlr,tlb,trb,lrb S3 tlrb N t,l,b N tl Climate scenario 2070 AHXA CHXA AXFE XHCR TDUI HUAE 1:1,40, TPXA S2 lb S2 lrb S3 b S3 tb,lb,rb S3 tlb,lrb,trb S3 tlrb N t,l,b N lb N tlb Climate scenario 2040 HUAE AHXA TPXA CHXA AXFE XHCR TDUI S2 rb S2 lrb S2 ltrb S3 t,l,r,b S3 tr,lb,lr,rb S3 tlb,trb,tlr S3 tlrb N t,l,b N tl,lb Climate scenario 2100 AHXA CHXA AXFE XHCR TDUI HUAE 1:1,40, TPXA S2 lb S2 lrb S3 l,b S3 tb,lb,rb S3 tlb,lrb,trb S3 tlrb N t,l,b N tb,lb N tlb Figure Land capability for cotton cropping in. Limitation factors; t, topography (slope type and slope gradient); l, soil (useful depth, texture, stoniness/rockiness, drainage, and salinity); r, erosion risk (soil erodibility, slope, vegetation cover, and rainfall erosivity); b, bioclimatic limitation. 217

14 CHAPTER Current Wheat suitablity Potato suitability 20 Area (x ) 0 80 Maiz suitability Sunflower suitability Cotton suitability S1 S2 S3 N S1 S2 S3 N Land capability classes Figure Distribution of the major land capability classes in the current situation and under the projected climate scenarios (2040, 2070 and 2100) for wheat, potato, maize, sunflower and cotton crops OVERVIEW OF GENERAL IMPACTS Figure 10-6 shows the distribution of the major land capability classes for the current situation and the projected climate scenarios, according to their corresponding area for the different studied crops. For Typic Fluvaquents (which 2.5% of the total area), the main land use is grassland, dominant in AL04, HU06 and SE05, classified as marginal under current scenario and climate projections. Marginal classification is caused mainly by shallow depth (20 cm, in AL04), and/or high salinity (34.6 and 28.9 ds/cm, in HU06 and SE05, respectively). In addition, the bioclimatic limitation becomes an additional limiting factor (Nlb) under the future projections. Soil units CA02- and CO07- show the best land capability for the studied crops. Under maize and cotton, these soils have a moderate land capability classification, and a marginal class is expected under climate scenario Variations of land capability are a result of the high variability of soil characteristics, which include useful depth, stoniness, texture, drainage, calcium carbonate concentration. In the studied area, an excellent land capability class is difficult to find because there is nearly always a soil characteristic or climate 218

15 RESULTS AND DISCUSSION parameter working as a limiting factor. Variation in climate conditions leads to variation in the results of the evaluation and, therefore, to a reduction of expected yield and lower land capability LAND CAPABILITY OF EL-FAYOUM LAND CAPABILITY UNDER IRRIGATION SCENARIOS The land capability of El-Fayoum province has been studied under four proposed scenarios of irrigation management, as shown in (Figure 10-7 and Figure 10-8). Land capability from irrigated regions where dominant soil type is Vertic Torrifluvents, under irrigation do not show differences between scenarios 1 and 2 (S2l). In these cases, the most important limiting factor is soil drainage. Areas with soil types Typic Haplocalcids, Typic Haplogypsids, Typic Torrifluvents, and Typic Torripsamments are classified as moderate (S3l), with calcium carbonate content, drainage, and soil texture as main limiting soil factors. On the other hand, marginal land capability subclasses (Nl) has been found in areas with Typic Haplosalids with soil salinity as limiting factor (Figure 10-7). In the irrigation scenario 3, land capability ranged from S2l to Nlb. Qarun Lake Nl Desert land Giza S3l S3l Desert land Wadi El rayan lakes El-Fayoum S2l Rocky outcrops Beni Swif River Nile Figure Land capability of El-Fayoum soil under irrigation scenarios 1 and

16 CHAPTER 10 Land capability classes are S2l (Vertic Torrifluvents), S3l (Typic Haplogypsids and Typic Torrifluvents), S3lb (Typic Haplocalcids and Typic Torripsamments) and Nlb (Typic Haplosalids) (Figure 10-8). Under rainfed conditions (scenario 4), all soil units are classified as marginal because of reduced rainfall or salinity. Soil depth and salinity represent the most limiting factors in the studied area, especially in the Typic Haplosalids, in the border of Qarun Lake (Figure 10-9). Therefore, we recommended implementing drainage systems able to leach soluble salts in the root layer. Calcium carbonate content affects the ph and thus has a significant effect on the availability of nutrients to the plant; the concentration of calcium carbonate therefore has an impact on land capability, especially on Typic Haplocalcids. Finally, heavy texture and poor drainage are among the most important soil limitations in Vertic Torrifluvents. Qarun Lake Nlb S3l Desert land Giza S3lb S3l S3lb Desert land Wadi El rayan lakes El-Fayoum S2l Beni Swif River Nile Figure Land capability of El-Fayoum soil under irrigation scenario

17 RESULTS AND DISCUSSION Figure A: salt-affected soil due to raise of the water level of Qarun Lake. B: barrier in the border of Qarun Lake built to limit the flow of salt water in the subsoil. 221

18 CHAPTER 10 Qarun Lake Nlb Desert land Giza Desert land Wadi El rayan lakes El-Fayoum Nb Rocky outcrops Beni Swif River Nile Figure Land capability of El-Fayoum soil under rainfed conditions. According to the general agro-ecological quality (land suitability), Vertic Torrifluvents, which cover approximately are the best soil type of the El- Fayoum depression (S2l) under the three irrigated scenarios. In contrast, the lowest land capability was determined in Typic Haplosalids, Nl in scenarios 1 and 2, and Nlb in scenario 3. Without the input of irrigation water, El-Fayoum depression would be a barren dessert not suitable for agriculture (Figure 10-10). Since agriculture relies so heavily on irrigation, changes in irrigation water input will have a large impact, this is likely relevant to many areas of the world with irrigated cropland, and as a more general principle to land uses where other inputs are much more influential than climate. The most strongly affected soils by reduction of water inputs are Typic Haplocalcids, Typic Torripsamments and Typic Haplosalids. Crops needing a high quantity of irrigation water such as maize, cotton, and sunflower will be highly sensitive to reduction of irrigation, and will be more affected than the other crops under irrigation scenario 3. Some recommendations for increasing soil productivity in the area have been suggested by Abdel Kawy and Belal (2011), 222

19 RESULTS AND DISCUSSION who proposed sub-soil plugging and addition of organic materials to overcome soil compaction, the establishment of drainage network systems to reduce water logging, artificial leaching in order to remove the excess of salinity and addition of gypsum to reduce soil alkalinity IMPACT OF URBAN SPRAWL ON AGRICULTURAL LAND The present study investigated the expansion of urban areas through arable land of El-Fayoum depression in the period Results show that El-Fayoum province lost more than 9800 ha of fertile soils due to urban expansion in this period (on average more than 490 ha per year, Figure 10-12). The built areas, infrastructures, and railways are included in the land resources database of El- Fayoum Province, According to this database, the urban area covered approximately 6,400 ha in 1992, and increased to 10,700 ha (6% of the total area) in 2001: It continued increasing up to 17,100 ha (10%) in Soils with the best classification decreased from 76,000 to 70,100 ha, while moderate-capability soils decreased from 14,100 to 13,300 ha. Oppositely, the area of marginal soils decreased from 51,300 to 48,000 ha during the same period. Totalizing, 6,800 ha of soil suitable for agriculture lost contrasting only 3,300 ha of marginal soil lost. In the past decades, researchers focused on the growth of Egypt s population compared to the increase in cultivated land. Abdel Hady et al. (1983) studied urbanization and the expansion of arable land during the period , and stated that, the area of cultivated land increased from 2.30 to 2.55 million ha (an increase of 11%) within this period (39 years), while the population increased from 15.9 to 38.2 million inhabitants (140%). They also concluded that the rapid urbanization was mainly onto the arable land and not into the desert. Urban spread onto the fertile agricultural land has affected a considerable area in El-Fayoum province within period between 1986 and Based on this study, these effects on prime agricultural lands should be considered in the planning of new urban areas in Kom-Oshim and Wadi El-Rayan areas, not through fertile soils. 223

20 CHAPTER 10 Figure (A) Expansion of residential areas onto farmland in El-Fayoum Depression. (B) Transport of bricks made of fertile soil material. 224

21 RESULTS AND DISCUSSION A Qarun Lake Nl S2l Desert land Giza S3l S3l S3l Desert land Wadi El rayan lakes El-Fayoum S2l Rocky outcrops Beni Swif River Nile B Qarun Lake Nl S2l Desert land Giza S3l S3l S3l Desert land Wadi El rayan lakes El-Fayoum S2l Rocky outcrops Beni Swif River Nile Figure Urban areas (in gray) expand onto agricultural soil over a period of 20 years (situation in 1986 in map A and 2006 in map B). 225

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24 Uncontrolled urban expansion contributes to soil sealing and loss of agricultural areas in El-Fayoum.

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26 Addition of manure to desert soils for transformation of desert land in productive farming areas.

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28 Agriculture land use and urban areas are concentrated in the valley of the river Nile.