Structure And Effect Of Oasis Shelter Forest In Southern Margin Of The Tarim Basin

Based on remote sensing analyses and the investigation of different structures of shelter forest, the landscape pattern of the study area was analyzed. Meanwhile, the allocation model of shelter forest system was studied. Also, the whole sheltering effect of oasis forest system was discussed in southern margin of the Tarim Basin. The results showed as follows:1)Based on Hotan Oasis TM remote sensing image in 2009, the study area was mainly composed of the desert and the gobi, which were about 89.04% of the total area Because of severe climatic condition, the area of forestland was smallest, which was about 0.57% of the total area.2)In the study area, the development of forestry ecosystem depended on environmental resources seriously. Solar and wind energy were important renewable natural resources. The degree of modernization of forestry was below the national average level in the study area. Human was the main power of forestry ecosystem in the study area.3)Through the study, shelter forest had three structure, the sparse structure accounting for 70% of the shelter forest. The survival rates of artificial vegetation were more than 56% in all plots. The survival rates of Elaeagnus oxcarpa Schlecht.+Populus alba var. pyramidalis Bge was highest All of artificial vegetation was in the pre-breeding or breeding period, and all of populations were increasing perimeter-class.4)In the study area, west wind was predominant type. In front of shelter forest, the air volume was more than the rear of shelter forest. Wind speed of wilderness was decreased obviously by shelter forest.5)Construction of shelter forest improved soil moisture conditions. The soil relative water content was greater than that of the original landform. But the soil characters were bad moisture content. The maximum relative water content of soil was only 3.89% in all plots, and the average is 1.31%.6)Construction of shelter forest was beneficial to improve soil bulk density. Soil conditions would be improved greater with increasing stand age. Phenomenon of soil salinization was obvious with increasing stand age in study area. Most allocation models of shelter forest were beneficial to improve soil organic matter content. Compared to western region of the study area that was close to desert region, the soil relative water content and the soil organic matter content were greater, but the total salt content was lower in eastern region of the study area that was close to oasis.