Soil and Water Losses from Various Types of Crop and Conservation Measures on Hillslope at Mae Sa Integrated Watershed and Forest Land Use Project, Changwat Chiang Mai

บทคัดย่อ

Soil and water losses from 4 conservation measures-bench terrace (BT), intermittent terrace (IT), hillside ditch (HD), contour bund (CB), and no measure plots (CK) were investigated using 3 replications of 5x20 m runoff plots constructed on 30% slope at Mae Sa Integrated watershed and Forest Land Use Project, Chiang Mai. Soil and water losses by storm were collected from 1980-1990 with the absence of data in 1984, 1988 and 1989. Results showed that the CK plot yielded the highest average of annual soil loss (31.3 tons/ha) followed by HD, IT, CB and BT with the value of 11.7, 9.6, 8.4 and 5.0 tons/ha respectively. The average annual water loss was largest in HD (91.3 mm) followed by CK,IT, CB and BT with the value of 90.4, 86.9, 81.7 and 78.7 mm respectively.