Geostatistical approach for land suitability assessment of some desert soils.

Due to the rapid growth of population in Egypt and the scarcity of land and water resources, the effective management of these resources has become a very urgent necessity to achieve the sustainable agricultural development. Consequently, land suitability assessment is an important tool to manage these resources appropriately. The objective of this study was to use geostatistical approach and geographical information system (GIS) to evaluate the land suitability for some essential crops in Toshka region, Egypt. Soil parameters such as gravel content, soil texture, pH, EC, CaCO3, ESP and CEC were determined, at 1.0 km grid soil sites. Afterward, the geostatistics approach using ordinary kriging interpolation and semivariogram were applied to produce a spatialized and detailed map for each soil parameter. Gaussian, Exponential and Spherical geostatistical models were used to define the spatial variability of soil properties based on RMS, MSE and RMSSE. Also, based on Storie equation the kriged interpolated maps were incorporated in the model builder within GIS environment to achieve the land suitability assessment. The results illustrated that, most of the investigated area are unsuitable (N) for vegetable crops. However, the study area is more promising for field crops where 42.71 % and 11.20 % of the total area are moderately suitable (S2) for barely and alfalfa crops respectively. Furthermore, the results confirmed that, some of orchids crops are very suitable for the study area whereas 6.80 % and 37.81 % of the studied area are highly suitable (S1) and moderately suitable (S2) for olives respectively. On the other hand, the results revealed that the results indicated that, the most limiting factor in the investigated area are EC, pH, calcium carbonate content, CEC and soil texture. Finally, it can be concluded that the geostatistical approach and GIS are powerful and effective tools for land suitability studies and consequently for sustainable planning of land use.