Soil Characterization and Land Suitability for the College of Agricultural Studies Farm - Shambat,EL Abbas Doka M. Ali

Abstract

The soils of the farm investigated in this study occupy an area of about 121 feddans. The land is mainly an experimental and demonstration farm owned by the College of Agricultural Studies, Sudan University of Science & Technology at Shambat. This area lies within the arid climate which is characterized by a very hot and humid summer, a mild and dry winter and marked seasonal variations in both rainfall and temperature. During these Months the highest rates of evaporation take place. The solid geology of the area is mainly composed of Nubian Sandstone covered by a relatively thick continuous formation of Nile alluvium deposits which form flat depositional plains. The natural vegetation of the area was disturbed as the area is continuously put under cultivation. The soils alluvium deposits were classified into recent alluvium; sub recent alluvium (old levees and bars) and old alluvium clay plain deposits. Although the soils are intensively cropped for teaching and research purposes, but adequate information regarding the physical and chemical properties of the soils under investigation were lacking, and no detailed soil map has ever been compiled. In the present work a detailed investigation was made to characterize the soils. Due to the soil variability in the area, a detailed survey with a high density of soil observations was adopted. Six profile pits and thirty augers have been fully described and sampled for the determination of important physical and chemical properties. Among these salinization, alkalization processes, potential soils fertility and soil water regime were examined. Results of laboratory determinations are discussed in chapter six. The field observations and laboratory findings were used for study of soil genesis and the compilation of a detailed soil map of the area. The estimation and mapping of salts and alkali in the surface soil of the farm were also carried out. For this purpose surface soil samples have been analysed for soil reaction, salinity, sodium adsorption ratio and exchangeable sodium percentage. Soil mapping units were separated according to differences in profile characteristics, taking into account the arrangement of stratification, textural variations and features of alluvial development. Laboratory results were also utilized in the differentiation between soil mapping units. Special 3 ‫‪suitability assessment was carried out and accordingly land suitability maps‬‬ ‫‪were produced for the investigated study area. The soils of the farm lie‬‬ ‫‪within suitability class S1 (Highly suitable) and S2 (Moderately suitable) with‬‬ ‫‪limitations of salinity, sodicity, permeability and texture. Since the study was‬‬ ‫‪designed as applied research, the recommendations outlined are related to‬‬ ‫‪future research studies and as well to agricultural practices to improve soil‬‬ ‫‪performance. These include implementing proper soil tillage operations and introducing‬‬ ‫.‪adequate fertilization programs to improve soil quality‬‬