Effects of Artificial Vegetation Types on Soil Moisture,Carbon and Nitrogen in the Hill and Gully Area of the Loess Plateau

Reforestation plays an important role in soil conservation and soil carbon sequestration.Five types of artificial vegetation were selected in the Wangdonggou watershed located in the hill and gully area of the Loess Plateau to understand the influences of artificial vegetation on soil properties.Soil moisture,soil or- ganic C(SOC),and total soil nitrogen were investigated under different types of vegetation.During dry sea- son,there was the intense water consumption characteristic in locust tree forest land and soil water content below the 200 cm depth ranged from 5.8% to 7.1%,showing a decrease with depth.Compared to grass- land,Chinese pine forest land had a soil water content of 15% in the same layer.Soil moisture used for ori- ental arbor-vitae,sea-buckthorn,and apple was mainly distributed between 20 and 200 cm from soil surface. Although natural rainfall had a supplement to the forest land,soil water within 50 cm of soil surface was re- charged in rainy season.Compared with grassland,SOC content was increased by 9.3% for Chinese pine and decreased by 40.1% for orchard.SOC contents of sea-buckthorn,oriental arbor-vitae,and locust tree were lower than those on grassland,although not significantly.