Comparison of soil loss and moisture content by using different cropping patterns for soil and water conservation on steep land   Vasuthep Kanchanadul, Nipon Udpuang, Pitak Intapan and Swasdee Boonchee   ABSTRACT         The comparison of soil loss and moisture content by using different cropping patterns on steep land was conducted on farmer field at Ban Huayjakan, Tumbol Pingkong, Chiangdao district, Chiangmai province on Wanghai soil series, soil series group 31 during the year 1993-1995. The experiment was randomized complete block design 3 replications, 7 treatments. The treatments were comprised of contour planting of upland rice, peanut and lab lab bean, strip cropping, strip cropping in association with vetiver grass hedge row, strip cropping in association with weedy strip and strip cropping in association with alley cropping (leucaena mixed with pigeon pea) respectively.       The results from the study revealed that the treatments of stripcropping in association with vetiver grass hedgerow, weedy strip and alley cropping leucaena mixed with pigeon pea hedgerow were remarkably reduced soil loss and runoff. In terms of crop yield and economic analysis, the strip cropping treatment and the strip cropping in association with alley cropping (leucaena mixed with pigeon pea), vetiver grass hedgerow and weedy strip tend to give higher yield and economic return although their planting area was smaller, it is anticipated that in the long term this trend will be significant and environmentally sound. Soil chemical analysis showed that soil pH of every treatments were all declined. The quantity of organic matter and phosphorus were increased in strip cropping and strip cropping in association with vetiver grass, alley cropping hedgerow and weedy strip. Bulk density of strip cropping in association with vetiver grass, weedy strip and alley cropping were decreased while monocropping treatments were increased.       Soil moisture content is significantly high in the treatment of stripcropping, stripcropping in association with vetiver grass, alley cropping and weedy strip barriers. Because these barriers slow down water runoff and increase infiltration rate into the soil. In conclusion, the treatment of stripcropping in associated with alley cropping would considered to be the most suitable conservation measure in order to maximizing the use of land for sustainable agriculture on the steep land of northern Thailand.         Keywords: Soil conservation, Cropping pattern