Soil Characteristics and their Variability at the Pilot farm of Um Bayada Agricultural Project

Abstract

This study was conducted in the pilot farm of Um Bayada Agricultural Project which is located in northern Darfur state between latitude 15 degrees north and between longitudes 27 1/2 and 26 1/2 degrees west. The main road which connects Al-Fasher to Hamrat Al- Sheikh in North Kordofan runs across Um Bayada area. Al-Meidoub dome and associated subsequent uplifts have influenced local and regional sequence of land formation and degradation. The dominate land topography in the study area is almost depressional cracking clay plain of the Um Bayada alluvium deposits. The climate of the study area is Semi-Desert type. Three main types of vegetations in the study area are Qoz vegetation, Basement vegetation and alluvium vegetation. The Water resources were Surface water and Underground water and so three major land use types are Traditional farming (rainfed), Traditional animal breeding and Wood cutting. This study aimed to characterize the soil of pilot farm, illustrating their variability, assess the land suitability for some selected main crops with defining the main soil constraints in relation to crop production and suggest sustainable soil management practices. The Grid soil survey method was followed in this study which involved field descriptions and taking of representative soil samples at intervals of 100 m apart dug with deep depth (200m). The collected soil samples were analyzed at the Soil and Water Sciences Dept. laboratory at Shambat. Laboratory chemical and physical characteristics include mechanical analyses, electrical conductivity (EC), Soil pH, soluble anions and cations and fertility status (nitrogen, phosphorus and potassium) based on soil sample extracts. Three different soil geomorphic units have been identified which are Depression cracking clay plain (DC), Cracking clay plain with gently undulating slope (CC), and Clay with very thin sand sheet (CS). The pilot is mainly composed of one map unit (75%) with consociations of minor inclusions of similar soil with different top soil phases. The soils were classified according to USDA soil taxonomy as Vertic Haplocambids. The results of field descriptions and laboratory analyses revealed that the soil of the pilot farm, has low to moderate permeability depending of dominant clay texture, none saline (0.3-2.5ds/m), slightly alkaline (7.6-8.0), with fertility limitations (S2f). According to soil suitability system the study find maximum of soil in class one (S1) with some limitations in class two (S2). The study recommended the soils of the pilot farm require a good soil conservation practices such as adding organic matter and plant cover to avoid the damaging effects of soil erosion. Good farming practices such as bush fallow and modern irrigation methods should be practiced for soil nutrient replenishment.