新疆策勒县固定沙地骆驼刺带状平茬对地表蚀积变化的影响

Influences of Alhagi Sparsifolia Stumping on Sand Surface Erosion and Deposition in Cele County of Xinjiang Uygur Autonomous Region

[目的]在对新疆策勒绿洲—沙漠过渡带绿洲边缘的固定沙地风蚀风积变化研究基础上,结合地表风速变化分析,探讨骆驼刺带状平茬和地形等对地表蚀积变化影响及其规律。[方法]采用插钎法、地形测量法、风速野外观测等方法。[结果]春季骆驼刺平茬初期,由于地表植被覆盖度大量减少,平茬带和保留带内地表主要以风蚀为主。夏季随着植被覆盖度的增加,地表主要以风积为主,地势较低、植被稀疏地表以轻微风蚀为主,秋季地表植被盖度基本保持最大和稳定,同时风力的减弱明显地减少了地表的风蚀量和风积量,地表主要以风积为主。[结论]春季骆驼刺带状平茬4m保留3m宽度利用方式不能有效地抵御地表风蚀危害,而夏秋季具有较好的防护效益。

[Objective]Based on previous research of wind erosion and deposition in oasis-desert zone,we aimed to explore the influences of Alhagi sparsifolia stumping and topography on sand surface erosion and deposition in Cele County of Xinjiang Uygur Atonomous Region.[Methods]Erosion pins were used and topographic surveys and wind velocity observations were conducted.[Results]The surfaces of stumping belts and reservation belts were dominated by wind erosion due to the large decreasing of vegetation coverage at the beginning of A.sparsifoliastumping in spring.Wind deposition occurred on the surfaces of A.sparsifolia quadrates due to the increased vegetation coverage in summer.Slight wind erosion mainly occurred on the surface with sparse vegetation and low topographic position.In autumn,as the vegetation coverage on the land surface maintained maximum and stable,wind erosion and deposition decreased,and the sand surface was dominated by wind deposition.[Conclusion]A.sparsifolia stumping with width of 4 mand 3 mfor stumping belt and preserving belt,respectively,may not effectively prevent wind erosion in spring,but caneffectively prevent wind erosion in summer and autumn.