The study deals with estimation of surface soil properties in Malaprabha command area. It can be broadly concluded that generalization of soil properties for an area is difficult since the soil and land use type varies drastically from one point to another in a short distance. It is only possible to have an average value for a particular type of soil. Also, it can be seen from the results that the percentage of silt-clay plays an important role in shaping the hydraulic properties of a soil.
It suggests that the new instrument (Disc Permeameter) used has these advantages - (a) it is easy to handle compared to the conventional double ring infiltrometer, and (b) estimation of various soil hydraulic properties like infiltration, saturated and unsaturated conductivity, sorptivity and pore characteristics can be done simultaneously.
However, from experience, it is noted that this instrument is not suited for extreme conditions of infiltration, and its calculation procedure is not foolproof. Also, the estimates of soil hydraulic properties obtained from the calculations are highly sensitive to θ0 to θ1 and hence, in situ measurement of the moisture content values are essential for better results.
It is necessary to conduct a detailed study using all the available instruments and methodologies, to find out the most accurate field method to estimate the soil hydraulic properties like infiltration and conductivity. Even though the use of rain simulators, which is considered as the most accurate method, involves high expenditure, it is always better to establish some relationship between soil properties estimated using various instruments and rain simulator. Such empirical equations can be used to convert the field estimates to more practical values, which can be used for hydrologic studies.
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