Document Type : Research articles.
Authors
1
Soils and Water Dept., Fac. of Agric., El Fayoum University, Egypt
2
National Authority for Remote Sensing and Space Sciences, Egypt
Abstract
This study is a trail for monitoring land cover changes by using Landsat
Imagery technique as well as determining soil suitability for irrigated agriculture
at 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 and
longitudes of 30o 24" and 30o 34"E. To achieve this target, Landsat Imagery
technique was carried out using two Landsat Thematic Mapper and Enhance
Thematic Mapper scenes acquired on 1984 and 2005 covering the north-western
part of El-Fayoum depression have been processed. A supervised Spectral Angler
Mapper approach was also applied to classify the images into four land use/cover
classes, i.e., urban, agriculture, water and desert areas. It was observed that some
desert areas had been transformed into agriculture and settlement during the
investigated period of twenty one year (1984-2005).
This study clarified that the reclaimed area for agriculture purposes during
the studied period reached 1726.91 ha, which constitute about 8.15 % of the total
area under study and nation settlement (arbanization) increased with about 310.06
ha, which couple nearly 1.46% of the total area. Whereas, the water area was
promoted with 31.48 ha, which equal about 0.22 %. All the land cover units were
increased 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 the
geophysical and anthropogenic processes such as salinity, alkalinity, water
logging, wind erosion, reclamation of new agricultural land and urbanization.
The satellite image interpretation map of the year 2005 was identified into
two main landscapes and thirteen landform units, based on the visual
interpretation of Landsat data ETM7 (Enhanced Thematic Mapper 7) and
applying the Landscape feature approaches. The validity of physiographic map < br />bounders were field checked to represent the different soil mapping units with
model soil profiles. Thirty-two mini pits were located and studied for setting up < br />the physiographic boundaries and characteristic of soil map legend. Also, the
variations of soil characteristics between the main identified physiographic units
were represented by eighteen soil profiles, which chosen to be full
morphologically described according to USDA (2003).
Soil taxa were surveyed according to the USDA (1975 and 2010), and the
studied soils could be categorized into three orders and six sub-groups, as
follows: Aridisols (Typic Calcigypsids, Lithic Calcigypsids, and Typic
Haplocalcids), Entisols (Typic Torriorthents and Typic Torrifluvents) and
Vertisols (Typic Haplotorrierts). According to the parametric system undertaken
by Sys and Verheye (1978), soil suitability classes of the studied area could be
categorized into four classes, i.e., highly (S1), moderately (S2), marginally (S3)
and not suitable (N1 & N2).
Keywords
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