Evaluation and Model Predictability of Infiltration Rate in Soils of Western Ghat Zone of Kolhapur District of Maharashtra, India

Abstract

Changes in land use can lead to differences in soil characteristics, particularly in the chemical and biological aspects of the soil. Soil infiltration rates are mainly influenced by hydraulic conductivity. The aim of this study was to determine the infiltration rate and to evaluate the accuracy of infiltration models (Philip’s, Horton’s, and Kostiakov’s models) in two different types of land uses. A total of 15 infiltration tests using a double-ring infiltrometer were conducted in the agriculture and horticulture lands of Rajarshee Chhatrapati Shahu Maharaj (RCSM) College of Agriculture, Kolhapur, Maharashtra. The results showed that soil bulk density did not differ between the two systems; however, there were variations in specific physical properties such as sand, silt, and clay content. Infiltration and cumulative infiltration rates were lower in agricultural soils compared with horticultural soils. The infiltration rate for agricultural land was 385 mm h-1, while horticulture land had 456.67 mm h-1. The infiltration rate decreased over time in both soil types until it reached a steady rate. At five minutes, a significant decrease in infiltration rate was observed for both types of lands (138 mm h-1 for agriculture land and 210.67 mm h-1 for horticulture land). Among infiltration models studied, Philip’s model provided the best fit for predicting the infiltration rate of agricultural soils. There were significant positive correlations between cumulative infiltration and sand content, electrical conductivity, and significant negative correlations with clay content, field capacity, permanent wilting point, available water, and calcium carbonate content. In conclusion, Philip’s model could effectively predict the infiltration rate of soils in the Western Ghat Zone, Maharashtra, performing better than Kostiakov and Horton’s models.