神府煤田风沙区采煤塌陷对风蚀的影响

目的]探究神府煤田风沙区采煤塌陷对风沙活动的影响,为矿区防治风蚀危害和植被恢复提供科学依据。方法]以塌陷区扰动地表为研究对象,通过野外定位观测,研究塌陷1~2a沙丘典型位置及不同的地表破损率对风蚀/风积量影响。结果]塌陷1a、塌陷2a和对照(非塌陷)沙丘不同典型位置的风蚀/风积深度分别达到-28.2,-45.6和-2.8cm,其整体的风蚀概率达60%以上,90%以上和10%以下。地表破损率越大,其地表风积过程越显著,且随着地表破损率的减小,风沙运动状态逐渐由风积填缝过程转化为风蚀过程,其风蚀/风积深度(Q)与地表破损率(V)呈多项式函数关系。结论]采煤塌陷有效地促进了风沙运动,改变了局部的风蚀/风积深度,可能引起固定半固定沙丘重新活化。

Effects of Coal Mining Subsidence on Wind Erosion Characteristics in Aeolian Desert Region of Shenfu Coal Mining

Objective] The influences of Shenfu coal mining subsidence on the movement of aeolian sand were studies to provide scientific basis and guidance for the controlling of wind erosion and recovery of vegetation. Methods] Based on local field observation in a typical sand dune, this paper studied the impacts of sand dune position and the surface damage ratio on the thickness of aeolian deposit. Results] The results showed that the thinkness of aeolian deposits on the ground that had undergone one year of subsidence and two year of subsidence were -28.2 cm and -45.6 cm, respectively; while the reference sand dune was -2.8 cm. The overall probabilities of wind erosion of the above three dunes were >60%, >90%, and<10%, respectively. Surface accumulation occurred more intensely on the surface with a higher damage ratio. The movement of wind-blown sand gradually shifted from accumulation or filling to wind erosion as the surface damage ratio decreased. The relation between the thickness of aeolian deposit(Q) and the surface damage ratio(V) can be described by a polynomial function. Conclusion] It was concluded that the coal mining-induced subsidence significantly promoted the movement of aeolian sand and changed the thickness of aeolian deposit locally, and it may reactivate fixed or semi-fixed dunes.