Soil loss evaluation of strip-tilled soybean cropping system in highland agriculture of Gangwon province

Large annual soil losses in the highlands of Gangwon necessitates growing appropriate crops and applying effective soil conservation measures to sustain agricultural productivity in the region.This study evaluates the effect of strip-tilled soybean / cover crop rotation on soil loss in the 2021, 2022 and 2023 growing seasons in 2, 7 and 15% slope lysimeters at the Highland Agriculture Research Institute in Gangwon.Cover crops were a 5:1 mixture of rye and hairy vetch planted during the fallow period, after soybean harvest.Cover crop biomass and soybean residue were left on the soil surface throughout the study.Soil losses under soybean and cover crop cultivation, and bare land were quantified.Cover management factor (C-factor) estimations of soybean and cover crops were made.Results showed that strip-tilled soybean reduced total soil loss by 19 to 109 times that of bare land in all the three slope lysimeters during the soybean growing periods.C-factors for the cultivation periods of strip-tilled soybean in all growing seasons were lower (0.0006 to 0.12) than the 12-year average C-factor (0.19) of conventionally tilled soybean.The reduction in c-factors could be attributed to the ability of soybean crops, strip tillage and soil surface cover to enhance soil conservation as slope gradients increase in the Highlands.Compared to bare land, cover crops also reduced total soil loss by 2 to 61 times in all the three slope lysimeters, during the cover crop growing periods.Applying strip tillage, rotating soybean with cover crops in the fallow period and maintaining soil surface cover in soybean cropping systems is an effective way of reducing soil loss and promoting agricultural productivity in the highlands of Gangwon.