The study attempts to do field and laboratory determination of soil classification properties in the Dudhnai river basin of Assam and Meghalaya. Point infiltration tests using double ring infiltrometer were conducted at various locations (forty-four sites) in respect of different land use conditions. Soil samples were collected from these infiltration testing sites.
The saturated hydraulic conductivity was determined in the field using Guelph Permeameter for the selected sites. The undisturbed soil samples and disturbed soil samples (50 cm below the ground) were collected and subjected to elaborate laboratory tests.
The disturbed soil samples were used for textural and consistency analysis. The percentage of sand, silt and clays were determined through sieve analysis and pipette method. Different engineering and index properties like moisture content, bulk density, dry density, specific gravity, plastic limit, liquid limit, void ratio, saturated density, degree of saturation, uniformity coefficient and coefficient of curvature were obtained from each sample.
The soil section was also measured in the field using a Tensiometer. Grain size curves were plotted and particle size distribution ranges have been identified using United States Department of Agriculture (USDA) criteria. Textural classification was identified using triangular classifications system of USDA as well as the Bureau of Indian Standards. Hydrologic soil groups were identified on the basis of infiltration characteristics using the Soil Conservation Services (SCS) method.
Download the report here:
/articles/soil-classification-dudhnai-representative-basin-assam-and-meghalaya-research-report