Soil Moisture and Vegetation Construction at Shaliuhe Town in Northern Qinghai Lake

Based on grain size analysis and soil moisture determination,soil moisture environment,causes of steppe degeneration,and vegetation suitable to developing were investigated at Shaliuhe Town in northern Qinghaihu Lake.The results show that the soil in the studied area is mainly composed of coarse silt.Soil moisture was rich in 2009 as a rainy year,and the seeping depth of gravity water reached 1.3 m in the rape land and about 0.5 m in the grass land,respectively.Soil moisture contents differed for various vegetation types,but decreased consistently with the depth.Soil moisture contents 0.8 m under the surface ranged from 8% to 11% for the majority of the grass lands,developing a weakly or moderately dried soil layer.This indicated insufficient soil moisture conditions and imbalanced water budgets,implying afforestation might not be suitable for this area.As dried soil layers extensively developed,drought-resistant grasses and other crops that consume less water are more desirable,in order to prevent water level recession of the lake.The cultivation area of water consuming plants like rape should be limited,and the exploitation of water resources from the rivers into Qinghai Lake should be well controlled.