Assessment of soil infiltration characteristics under micro-watershed in North Eastern part of Karnataka, India

Abstract

In order to assess the soil infiltration characteristics,a standard field-test method was conducted by means of double-ring infiltro-meters under Patapura micro-watershed in Manvi taluk, Raichur district representing north-eastern dry zone (Zone-2) of Karnataka. The rate of infiltration in a micro-watershed was estimated under representative three different land forms viz., upland, midland and lowland topography. The results were shown that the steady infiltration rates of a micro-watershed in these land forms were decreased from the initial measurement upto the end of 360th minutes, the values of infiltration rate remained firmly stable at 2.1, 1.4, and 0.7 cm hr-1 for upland, midland and lowland soils, respectively. The cumulative infiltration (26.3 cm) and terminal infiltration rate (2.1 cm hr-1) were observed highest in case of upland area. Similarly, in midland and lowland areas were recorded lower amount of cumulative infiltrations (22.0 cm and 11.8 cm) and infiltration rates were also showed lowest i.e., 1.4 cm hr-1 and 0.7 cm hr-1, respectively compared to upland area. The terminal infiltration rate followed the order: lowland < midland < upland physiographic locations. The factors influencing infiltration rates are soil texture, soil organic matter, soil sodicity, porosity, bulk density, topography and initial soil moisture content in the testing area. Therefore, increasing of soil infiltration, reducing runoff velocity and volume are the main aims for soil and water conservation in the watershed area for management and development of soil profile