Evaluation of soil fertility status of Regional Agricultural Research Station, Tarahara, Sunsari, Nepal

Abstract

Soil fertility evaluation of an area or region is most basic decision making tool for thesustainable soil nutrient management. In order to evaluate the soil fertility status of theRegional Agricultural Research Station (RARS), Tarahara, Susari, Nepal. Using soilsampling auger 81 soil samples (0-20 cm) were collected based on the variability of land.The collected samples were analyzed for their texture, structure, colour, pH, OM, N, P2O5,K2O, Ca, Mg, S, B, Fe, Zn, Cu and Mn status. The Arc-GIS 10.1 software was used for thepreparation of soil fertility maps. The soil structure was granular to sub-angular blockyand varied between brown- dark grayish brown and dark gray in colour. The sand, silt andclay content were 30.32±1.4%, 48.92±0.89% and 20.76±0.92%, respectively andcategorized as loam, clay loam, sandy loam, silt loam and silty clay loam in texture. The soilwas moderately acidic in pH (5.98±0.08). The available sulphur (2.15±0.21 ppm), availableboron (0.08±0.01 ppm) and available zinc (0.35±0.03 ppm) status were very low, whereasextractable magnesium (44.33±6.03 ppm) showed low status. Similarly, organic matter(2.80±0.07%), total nitrogen (0.09±0.004 %), extractable calcium (1827.90±45.80 ppm)and available copper (1.15±0.04 ppm) were medium in content. The available phosphorus(39.77±5.27 ppm), extractable potassium (134.12±4.91 ppm), and available manganese(18.15±1.15 ppm) exhibits high status, while available iron (244.7±19.70 ppm) was veryhigh. The fertilizer recommendation can be done based on determined soil fertility statusto economize crop production. Furthermore, research farm should develop future researchstrategy accordance with the prepared soil data base.