DETECTION OF SUITABLE SOILS FOR ZERO-TILL WHEAT SOWING IN GUJRANWALA USING GITs

Abstract

Sowing wheat after rice harvesting without land preparation (Zero-till) is a resource conservation technique. It reduces cost and increases wheat yield because of 2-3 weeks early sowing. But all types of soils are not equally suitable for sowing of zero-till wheat. In order to delineate the suitable soils for zero-till wheat sowing better understanding of soil variability patterns has been required. The Geographical Information Technologies were utilized to detect the soils suitable for zero-till wheat sowing in Gujranwala district. Salt affected areas were detected by integrated analysis of satellite images and published maps by Soil Survey of Pakistan. Plowpan occurrence was delineated using the field surveyed soil bulk density profile data. Different methods of interpolation were compared to generate surface from soil point data. Finally, Kriging interpolation method was used. Weighted overlay analysis was performed to define the suitability classes based on soil profile surfaces. The soil texture and drainage characteristics were integrated to extract the ideal conditions. GIS vector based analyses were performed to integrate the entire datasets for zero-till suitability mapping. The findings from this thesis indicate that, 16% of the study area soil is under salinity problem. The extent of 13 % is found suitable for zero-till wheat sowing which consist of Shahdara, Sialkot, Sodhra, Khair, Pindorian and Wazirabad soil associations. 33 % of study area is found unsuitable for zero-till wheat sowing, relatively larger area found moderately suitable covering the 48 % of study area . Remaing area is under urban built-up area and not useable for agriculture.