Soil fertility assessment and GIS mapping of flood affected Agro ecological unit in Kerala

Abstract

A study was undertaken to evaluate the soil quality and changes in the fertility status of post flood soils of Agro-ecological unit (AEU) 9 in Alappuzha district of Kerala. Representative geo referenced surface soil samples (0-20 cm) were collected and analyzed for pH, organic carbon, N, P, and K. Soil nutrient index were worked out and GIS based thematic maps were prepared. The results of the study revealed strongly acidic to extremely acidic soils in the flood affected areas of AEU 9. Organic carbon content, available phosphorous and potassium were increased while widespread deficiency of available nitrogen were observed. Nutrient index in terms of organic carbon, nitrogen and phosphorous were medium, low and medium respectively. Nutrient index for potassium was medium to high. The results outline the need for regular liming to control soil acidity and soils should be supplemented with nitrogen and phosphorus to improve soil quality.