The Effect of Soil Moisture in Red Soil Slope by Bamboo-type Contour Trench

In order to study the effect of bamboo-type contour trench on soil moisture content in red soil slope, 4 slope plots on bare land, soil and water conservation forest, soil and water conservation forest+bamboo-type contour trench and soil and water conservation forest+bamboo-type contour trench+litter-covered land were selected for a full year sampling test, in the Laohushan small watershed of Taihe County, Jiangxi Province. The results showed that the water storage capacity was relatively larger in bamboo-type contour trench, ranging from 138.1 mm to 237.3 mm in soil depth of 60 cm, while the soil water storage in the water and soil loss area under the conservation forest was relatively the smallest. The soil moisture content was relatively smaller in the land of soil and water conservation forest, which was below 16% in each soil layer in each month. Nevertheless, the soil moisture content was mainly above 16% in soil and water conservation forest+bamboo-type contour trench plot, which demonstrated that bamboo-type contour trench could serve to store soil moisture. The soil moisture content was relatively large in the soil and water conservation forest+bamboo-type contour trench+litter-covered plot even in September when the monthly rainfall is the least. Compared with other treatment plots, the lowest soil moisture contents were always in the plots under the soil and water conservation forest, while the highest was in the bare land or the soil and water conservation forest+bamboo-type contour trench+litter-covered land in the trench of which the soil moisture content was 79%−146% higher than that of soil and water conservation forest plot. Compared with the same treatment plots, the soil moisture content inside bamboo-type contour trench was much larger than outside. The bamboo-type contour trench can play a role in water storage and retention, and is of great importance for flood control and drought relief. It is one of the radical measures to regulate and control water volume in the eroded red soil region of south China.