College of Desert Control Science and Engineering, Inner Mongolia Agricultural University, Hohhot, 010018, China.
Wind Erosion Key Laboratory of Central and Government, Hohhot, 010018, China.
Sci Rep. 2020 Feb 13;10(1):2566. doi: 10.1038/s41598-020-59538-7.
Wind erosion is a huge challenge for ecologists to stabilize sand dunes and to change them into stable productive ecosystems. In order to better understand its role in the process of ecological restoration, the sediment grain-size characteristics of compound sand barrier were evaluated through field experimental observation. The results indicated that the compound sand barrier was mainly composed of extremely fine sand and fine sand, and the fine sand and extremely fine sand in the inner side were higher than the east and west sides of the compound sand barrier. Due to the blocking effect of compound sand barrier, the Sorting Coefficient became better, the Skewness belonged to the positive deviation and the Kurtosis presented leptokurtosis distribution. Moreover, while the cumulative frequency distribution curve in the inner side became steeper, the slope increased and reached the top of the curve ahead of time. The effect of wind environment and vegetation coverage on the surface sediments showed that the average annual wind velocity and vegetation coverage was negatively correlated with the average grain-size, but positively correlated with the Sorting Coefficient. There was a significant correlation among the annual wind speed, vegetation coverage, average grain-size and Sorting Coefficient, which indicated that vegetation coverage and wind environment was the key factor leading to the difference of surface sediments in this area. Collectively, the establishment of compound sand barrier is one of the most effective methods of sand-fixing with engineering measure in the arid desert regions. Therefore, given the complexities of agricultural systems, stubble retention and black film covered during harvesting and incorporation of the stubble into soil in the next spring appears to be the best choice in the dry northern China where farmlands suffer serious wind erosion.
风蚀是生态学家稳定沙丘并将其转变为稳定的生产性生态系统的巨大挑战。为了更好地了解其在生态恢复过程中的作用，通过野外实验观测评估了复合沙障的泥沙粒径特征。结果表明，复合沙障主要由极细砂和细砂组成，内侧的细砂和极细砂高于复合沙障的东、西侧。由于复合沙障的阻挡作用，分选系数变好，偏态属于正偏态，峰态呈尖峰态分布。而且，内侧的累积频率分布曲线变得更陡，斜率增加，提前达到曲线的顶部。风环境和植被覆盖对地表沉积物的影响表明，平均风速和植被覆盖率与平均粒径呈负相关，与分选系数呈正相关。年风速、植被覆盖率、平均粒径和分选系数之间存在显著相关性，这表明植被覆盖率和风环境是导致该地区地表沉积物差异的关键因素。总之，在干旱沙漠地区，建立复合沙障是工程措施固沙的最有效方法之一。因此，考虑到农业系统的复杂性，在遭受严重风蚀的中国北方干旱地区，收获时保留秸秆并覆盖黑膜，以及将秸秆纳入土壤中，似乎是最佳选择。
