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This study is a trail for monitoring land cover changes by using LandsatImagery technique as well as determining soil suitability for irrigated agricultureat the north-western outskirt of El-Fayoum depression during a period of 1984-2005. The studied area lies between latitudes of 29o 19" and 29o 26" N andlongitudes of 30o 24" and 30o 34"E. To achieve this target, Landsat Imagerytechnique was carried out using two Landsat Thematic Mapper and EnhanceThematic Mapper scenes acquired on 1984 and 2005 covering the north-westernpart of El-Fayoum depression have been processed. A supervised Spectral AnglerMapper approach was also applied to classify the images into four land use/coverclasses, i.e., urban, agriculture, water and desert areas. It was observed that somedesert areas had been transformed into agriculture and settlement during theinvestigated period of twenty one year (1984-2005).This study clarified that the reclaimed area for agriculture purposes duringthe studied period reached 1726.91 ha, which constitute about 8.15 % of the totalarea under study and nation settlement (arbanization) increased with about 310.06ha, which couple nearly 1.46% of the total area. Whereas, the water area waspromoted with 31.48 ha, which equal about 0.22 %. All the land cover units wereincreased account on the expanse of desert unit, which decreased with 2097.20 ha(9.78% of the total studied area). These increases are more attributed to thegeophysical and anthropogenic processes such as salinity, alkalinity, waterlogging, wind erosion, reclamation of new agricultural land and urbanization.The satellite image interpretation map of the year 2005 was identified intotwo main landscapes and thirteen landform units, based on the visualinterpretation of Landsat data ETM7 (Enhanced Thematic Mapper 7) andapplying the Landscape feature approaches. The validity of physiographic map bounders were field checked to represent the different soil mapping units withmodel soil profiles. Thirty-two mini pits were located and studied for setting up the physiographic boundaries and characteristic of soil map legend. Also, thevariations of soil characteristics between the main identified physiographic unitswere represented by eighteen soil profiles, which chosen to be fullmorphologically described according to USDA (2003).Soil taxa were surveyed according to the USDA (1975 and 2010), and thestudied soils could be categorized into three orders and six sub-groups, asfollows: Aridisols (Typic Calcigypsids, Lithic Calcigypsids, and TypicHaplocalcids), Entisols (Typic Torriorthents and Typic Torrifluvents) andVertisols (Typic Haplotorrierts). According to the parametric system undertakenby Sys and Verheye (1978), soil suitability classes of the studied area could becategorized into four classes, i.e., highly (S1), moderately (S2), marginally (S3)and not suitable (N1 & N2). |
