AbstractKnowledge of the soil hydra

Abstract
Knowledge of the soil hydraulic properties is indispensable to solve many soil and water management problems related to
agriculture, ecology, and environmental issues.Soil hydraulic properties are key factors that regulate the movement of
groundwater and transport of solutes.The most important hydraulic properties of soils are the soil water retention curve (SWRC)
and saturated hydraulic conductivity (ks). Determination of these hydraulic properties is needed for many studies and applications
related to irrigation, drainage, water movement and solute transport in the soil.Although many advances are made for direct
measurements of SWRC and ks, they are usually time consuming and costly. Some attempts have been made to indirectly predict
these hydraulic properties. The objective of this study was to derive an empirical relationship to estimate soil water retention
curve from saturated hydraulic conductivity. One hundred and one soil samples were collected from agricultural and forest sites
at different depths, at different locations in the Pavanje river basin that lies in the southern coastal region of Karnataka, India. The
saturated hydraulic conductivity was measured in the laboratory by variable falling head method using Permeameter and soil
water retention curve data was obtained through pressure plate apparatus for all the agricultural and forest soils. Prediction
accuracies were evaluated using coefficient of determination, root mean square error, mean error,Akaike Information Criteria,
between measured and predicted values.The results obtained from the prediction of soil moisture retention curve from saturated
hydraulic conductivity, shows that the developed relationship are reasonably useful to get the soil moisture retention curve for the
soils of agricultural and forested hillslopes of the region under consideration.