Geospatial Approach in Assessing Land Suitability for Agro-Horticulture in North Indian Hilly Region

Abstract

The study illustrates the use of Geographic Information System (GIS) tools and numerical Multi-Criteria Evaluation (MCE) techniques for selection of suitable sites for Agro-horticulture development of a Sitla rao watershed in Dehradun region at Indian Institute of Remote Sensing (IIRS),ISRO.This study was conducted to identify suitable sites for Agro-horticulture development of a Sitla rao watershed in Dehradun using GIS-based multi-criteria evaluation of slope, aspect, land use and land cover ,soil factors such as soil texture, depth, drainage, coarse fragments and erosion. Land use and land cover map (Sentinel 2A) and eight thematic information layers were analyzed using ArcGIS 10.8 software to identify suitable areas in Sitla rao region of Dehradun. It focuses on GIS based Overlay Weightage method. The undulating terrain, flat to moderate, well drained, varied depth and different soil characteristics give the impression to find out suitable sites for agro-horticulture. In this study nine factors (slope, aspect, land use and land cover, soil characteristics such as soil texture, depth, drainage, coarse fragments and erosion) were identified for criteria evaluation. Using physiographic map, respective soil texture, soil depth, soil drainage, coarse fragments and erosion map generated. With the generated criteria, maps are standardized using the pairwise comparison matrix method (Saaty,1980). Weights for each criterion is generated by comparing with each other according to their importance. Criteria weights and maps are combined using weighted overlay method. Pair wise comparison matrix indicates weights for slope (=12.70%), aspect (4.83%), land use and land cover (=2.67%), soil drainage (=8.60%), soil texture (=13.07%), temperature (=23.47%), soil depth (=29.97%), coarse fragments (=2.80%) and soil erosion (=1.89%). Consistency Ratio CR (=0.09) <0.10 indicated a reasonable level of consistency in the pairwise comparisons. The final suitability map was obtained from both weighted sum overlay and Spatial Analyst Tools covering an area of 49 sq.km. After suitability analysis it was found from the available area 0.3921 sq km falls under unsuitable(N), 25.46 sq km under restricted, 2.149 sq km under highly suitable (S1), 14.694 sq km under moderately suitable (S2), and 5.329 sq km under marginally suitable (S3).