Use of Gis for spatial mapping of soil fertility in Dhanushadham Municipality, Dhanusha, Nepal

Soil fertility evaluation is an important aspect in the context of sustainable agricultural production of an area. This study was carried out to find the soil fertility status of the Dhanushadham Municipality, Dhanusha, Nepal located at 26°52'N, 86o02'E using GPS and GIS Using Google Earth Pro (GEP) and ArcGIS, 61 soil samples were collected based on land use, slope, and aspects. The soil's texture, pH, total nitrogen, available phosphorous, and potassium levels were all measured. Most of the study area (36.35%) has loam soils, followed by sandy loam soil (28.17%). The soil pH ranged from 5.2 to 7.5, indicating that it was strongly acidic to nearly neutral. Soil organic matter (SOM) ranged from 1.14% to 1.83% with a mean value of 1.52% in most of the soil. Total nitrogen was 0.08%, available phosphorus was 120.96 kg/ha, and available potassium was 146.13 kg/ha, respectively. In the study area, total nitrogen was found to be medium, phosphorus found to be high, and potassium was found to be low. To maintain soil nutrient status, organic manure, reduced use of chemical fertilizers, and different soil management practices should be used. The study concludes that GPS and GIS-based soil fertility mapping assists farmers, scientists, planners, researchers, and students in providing soil test-based fertilizer recommendations for sustainable soil management and developing future farm research strategies.