Runoff and soil loss behaviour with different conservation practices under new tea plantation in the Nilgiris

An experiment was conducted to study the influence of conservation measures on runoff and soil loss in new tea plantations at Central Soil and Water Conservation Research and Training Institute, Research Centre, Udhagamandalam, Tamil Nadu during 1995 to 2002. Three conservation measures viz., Contour Staggered Trenching (CST), Cover crop of beans and combination of CST + beans with control (without any conservation measures) were practiced under one yearold B-6 tea clones planted in double hedge planting (135 cm x 75 cm x 75 cm) with 65 cm between raw to row within the double hedge. The average annual runoff was reduced by 51, 47 and 29 per cent in CST+beans, CST alone and cover crop of beans, respectively in comparison to control. The soil loss was reduced by 64, 68 and 25 percent in CST+beans, CST alone and cover crop of beans, respectively in comparison to control. The minimum runoff and runoff events in CST + bean followed by CST shows the dominant effect of contour staggered trenches in controlling runoff which in turn reduces the soil loss. The quadratic relationship between rain fall-runoff and rain fall-soil loss for each depth class found to be best fit having coefficient of determination (R²) more than 0.7 showing a good agreement except few cases where it ranges between 0.5–0.7 among different treatments.