GPS and GIS based soil fertility assessment and mapping in Bihariganj Block of Madhepura District

Abstract

This study examines soil chemical properties and micronutrient availability in Bihariganj block, Madhepura district, Bihar, India, using GPS and GIS technologies. Analyzing 92 soil samples from a 1 km grid, results showed a pH range of 5.6-8.5 (mostly neutral), low salinity (average EC 0.23 dS/m), and variable organic carbon (0.11-0.84%). Micronutrient analysis revealed sufficient Cu and Fe levels (with some Cu toxicity concerns), higher Mn in acidic soils, and widespread Zn deficiency. Soil pH strongly influenced micronutrient availability, with acidic soils enhancing Fe, Mn, Cu, and Zn solubility. Organic carbon showed a weak to moderate correlation with nutrient retention. The study underscores the need for integrated soil management, including pH optimization, organic matter enrichment, and targeted Zn fertilization, to improve soil health and crop productivity. Long-term monitoring and site-specific strategies are recommended for sustainable agriculture.