GIS - Comprehensive Analytical Approach for Soil Use by Linking Crop Soil Suitability to Soil Management and Reclamation
Abdrabelnabi M. Abd El-Hady and Emad F. Abdelaty
Region of Alex-Cairo Desert Road (Egypt) has agricultural potentiality to contribute to food security; therefor the soil of the farm of Nile Company, at 63 Km Alex-Cairo Desert Road, was evaluated by applying our comprehensive analytical approach of evaluation. Soil physical and chemical characterization conducts to soil numerical classification and crops soil suitability that has the advantage to guide the practices of soil management and reclamation.
Soil physical characterization leaded to univariate numerical soil classification that pointed that the major phases were moderately soil profile depth (1996.76 Feddan), moderately permeability (3543.90 Feddan), low holding capacity (2608.11 Feddan) and sandy loam textural phases (1800.83 Feddan). Soil chemical characterization led to univariate numerical soil classification which showed that the major classes were moderately saline (3124.76 Feddan), non-sodic (3531.04 Feddan) and non-calcareous classes (3851.35 Feddan).
The study referred to selection salt tolerant crops as cultural practice for managing soil salinity. Leaching requirements (LR) of reclamation purposes, for different EC-tolerance crops, were determined to output GIS–EC edaphological map. This map that may guide the process of saline soil reclamation was composed of four mapping units having the area of 298.76, 3124.76, 845.35 and 16.11 Feddan. The map that determined the spatial distribution of (LR) application showed that: the max allover total leaching water requirements (ATLR) of 13189090.54 m3 are to cultivate all studied area by orange. (b) Wheat is more salts tolerant than orange. Accordingly, the max allover total leach requirements were 1557042.70 m3/studied soil to plant wheat, which were less greatly than the case of orange cultivation.
GIS-ESP edaphological soil classification was elaborated by assigning ESP thresholds of tolerant crop range to GIS-ESP soil map to produce the GIS-ESP edaphological map. The map divided the studied area into three categories of ESP tolerance crop soil; extremely sensitive ESP crop (1355.09 Feddan), sensitive ESP crop (2845.73 Feddan) and moderately tolerant crop (84.88 Feddan). This edaphological soil classification enabled to calculate edaphological gypsum requirement (GR) for different ESP-tolerance crops. GIS-EC and ESP overlaid maps output the soil multivariable chemical classification. The overlaid GIS-EC-map classified the studied soils into five variants; non saline-non sodic soil (298.80 Feddan) moderately saline-non sodic soil (2701.42 Feddan), highly saline-non sodic soil (535.95 Feddan), moderately saline-sodic soil (424.04 Feddan), and highly saline-sodic soil (325.47 Feddan)
Land suitability determined the main limitation factors to guide soil management and reclamation. Wheat soil suitability classified the soils into of the area was conditionally suitable (S4 =57.3%) and (S3 = 42.7%). As for faba bean, the soils had the three classes; marginally suitable (S3= 47.6%), conditionally suitable (S4 = 30.7%), and moderately suitable (S2 = 21.7%). Grape soil suitability map distributed into two main classes; 63.8% (moderately suitable = S2), 26.1 % (marginally suitable =S3). Soils majority was moderately suitable (S2 = 64.5 %) for olive tree. 61.79 % (moderately suitable = S2), 19.64 % (marginally suitable = S3), represented the majors of potato soils suitability. The largest area of the study area (88.02 %) was classified as highly (S1 = 40.5%) and moderately suitable (S2 = 47.5%) for tomato.
Keywords: GIS, Soil numerical classification, GIS-EC and ESP overlaid maps, GIS-EC edapholical map, Soil GIS-ESP edapholoical soil classification, Multivariable chemical classification, Soil suitability.