The Impact Of Different Sand Barriers On The Growth Of Salix Psammophila In Moving Sand Dune

The less vertical salix sand barrier and the less vertical straw-checker sand barrier were the common mechanical sand barrier whose drawing materials were convenient and low cost and setting are easy, because of these reasons, these sand barriers were widely used. These sand barriers usually cooperate with vegetation measures because of their good use in improving the surface microclimate and improving the quality of soil. This paper was based on the salix psammophila as the research object, through the selection of sand barriers material and laying mode to setting up different size and porosity of the sand barriers. Through the study of the six growth index of salix psammophila and windbreak effect of the combination of salix psammophila shrub and salix sand barrier, the suitable types of sand barriers are determined to provide a basis to guid the production practice in the local for the selection of sand barriers in the salix psmmophila.The results show that:(1) The protective benefit of less vertical larrice of salix sand barriers were better than less vertical straw checkerboard barriers and the blundle of slix psammophila checkerboard tile in the growth index of salix psammophila and windbreak effect aspect.(2) Further studies show that, comparing with the sand barriers those size were lmxlm,2mx3m and 3mx3m, the sand barriers those size are 2mx2m play a grester role on the growth promoting effect of the growth index of salix psammophila in the area of Qixi Lake. Compared with the other sand barriers, the height, crown width, number of branches, diameter of branch and branch length of salix psammophila in the sand barriers of2mx2m were respectively increase by 39.51%、78.41%、54.67%、79.21%、33.35%. And the windbreak effect of salix psmmophila was more obvius by the defence of sand barriers those size were 2mx2m.(3) In the constrast of the four degree of lighting tests of 75%,80%,85%,90%, the sand barriers whose porosity were 75% will be better for others in promoting the height, crown width, number of branches of salix psammophila and had greater windbreak effect.