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Abstract The current investigation aims to study the geomorphological and pedological characteristics including soil classification and land capability evaluation for soils in the area located at southeast of ELSadat city, Menoufia governorate, Egypt. Calculating soil available water using soil water characteristic curve (SWCC), testing and validating Van Genuchten (VG) model in simulating SWCC, developing regression equations to predict the expected soil salinity over time and land use/land cover change detection within 20 years are also carried out. The integration of Remote Sensing (RS) and Geographic Information System (GIS) techniques was used to perform this work. This work could be presented important information about the potentiality of land resources for proper sustainable agriculture of these soils. The interpretation of geomorphic map produced using RS and GIS technology indicated that, there are three main identified geomorphic units including eight landforms in this area. These units are Alluvial Plain (Depression, Low and High Terraces), Aeolian Plain (Low, High Terraces and Plateau) and Pedi Plain (Low and High Terraces). Nineteen soil profiles were selected representing these landforms. The land and site features are observed and registered. Most of soil profiles were dug deep down to 150 cm. Profiles were morphologically described, and then disturbed and un disturbed soil samples were collected representing the subsequent layers in each profile for integrated physical and chemical analyses. Also, some available irrigation water samples were collected and analyzed especially for land capability evaluation. The results could be summarized as follows: • Site examination of the studied soils exposed that; the soils have almost flat to gently undulating and gently sloping topography. The elevation of the studied area varies between 10 to 95 m. above sea level. Land surface and most of studied soils are slightly gravelly to very gravelly. Most of studied soils are deep to very deep and mostly have well to excessive drainage system. • The studied soils have light texture mostly gravely sand and loamy sand with rapid hydraulic conductivity. The soils vary between weak to moderate sub angular to granular structure and some layers have single grains. Their consistence varied from slightly hard to soft when dry and friable to loose when moist according to their content of fine particles. Most of these soils have brown color degrees with hue of 10YR and some of them have reddish yellow color with 7.5 YR. • The physio-chemical data of the studied soils revealed that, the most of these soils have slightly alkaline reaction, are non-saline and not sodic. Moderate salinity and sodicity effect are found in a few soils in limited studied areas that having moderately deep soil materials. The studied soils are slightly to moderately calcareous according their CaCO3 content. Organic matter (OM), cation exchange capacity (CEC) and gypsum are low. • Spatial distribution maps for the main soil properties in the studied area are produced using the GIS technique software. • The studied soils were classified up to sub great group level according to Soil Survey Staff (2014). Most of the studied soils (about 98.35%) haven’t any diagnostic sub-surface horizons. Therefor these soils are classified under Entisols whether as Typic Torripsaments (62.25%) or Typic Torriorthents (36.10%). Features of Sodic sub horizon was detected in very small soil area (1.65%) therefore, these soils are classified under Aridisols as Sodic Haplocambids. • Evaluation of soil salinity during 22 years in comparison with a previous studies on some soils belongs to the studied geomorphic units indicated a clear decrease in salinity. This could be correlated with the expanded and continued agricultural practices in these areas. This, also, can be indicated that, there is no current or future risk of soil salinization, especially with the good quality of available irrigation water resources in these areas. This encourages agricultural expansion horizontally and vertically and increases productivity per unit area of cultivated soil. • The SWCC were measured and thus the irrigation requirements, i.e. soil available water, were determined. The model of VG was chosen and tested for the further use in estimating SWCC in similar soils. • Land capability evaluation was done using the integration between ALES-Arid model and ArcGIS software based on the main soil characteristics, soil fertility and irrigation water quality indices. Accordingly, most of the studied soils (92.17 % of the total area) are affiliated to the fair capability (C3) class, mainly due to their sandy texture. Only a few soils (4.52 %) have a good capability (C2) class as well as about 3.31 % have a poor capability (C4) class. • The spatial-temporal changes in land use/land cover (LULC) classes (agricultural, barren and urban lands) were detected using the classification and post-classification processes of the studied Landsat images over a 20 years’ period from 2000 to 2019. The overall changes in LULC classes during the period from 2000 to 2019 indicated that, there is an increase in the total area of agricultural land and built-up land at the expense of the barren land. • Integration of RS, GIS was used to produce different necessary maps and figures for the resulted data. |