Protection Benefits of Farmland Shelterbelt in Oasis Periphery of Hotan Region

Populus allba and Calligonum mongolicunl farmland shelterbelt was planted in a moving sandy land outside newly reclaimed farmland in Hotan region.HOBO anemoscope,hygrograph,thermograph and sand sampler were set in the front and back of the shelterbelt,and the apparatus were conducted to determine the protection benefits of the farmland shelterbelt.The study was expected to provide a theoretical basis for building the outside protection forest and rationally exploiting and utilizing land resources in the deserted area.Results showed that wind-break potency of the shelterbelt decreased with the height.When wind velocity was greater than 6m/s,wind-break potencies for the Populus alba belt and Calligonum mongolicunl belt at the height of 0.5mwere 67.2%and 94.5%and at the height of 3m,31% and 33%,respectively. Wind-break potency decreased with wind velocity and the Populus alba belt's effect was more obvious. Farmland shelterbelt played an important role in decreasing wind velocity and reducing wind erosion,and sand transportation in the shelterbelt was about 10%as compared with mobile sandy land.Besides,radiation and temperature were decreased,and humidity was increased sharply under the shelterbelt.Farmland shelterbelt plays an effective role in decreasing wind velocity,fixing mobile sandy land and optimizing the microclimate.