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小叶锦鸡儿灌丛沙丘是内蒙古高原阴山北麓农牧交错带的主要风沙堆积类型。野外调查表明灌丛沙丘在该区主要分布在耕地、冲积扇下风侧和村落周围等人类活动频繁的地段。根据对耕地、冲积扇下风侧典型样地灌丛沙丘形态参数的详细测量和沙丘及丘间地气流的系统观测结果,发现灌丛沙丘覆盖度及风沙沉积量顺风向减小,近地面气流空气动力学粗糙度顺风向减小;在沙丘单体,风速廓线由迎风坡经丘顶至背风坡趋于复杂。在沙丘形态诸参数中,沙丘高度与水平尺度之间存在良好的幂函数相关,表明在目前风况和沙源环境中该区灌丛沙丘处在加积增高阶段,但其速率小于水平扩展。该区灌丛沙丘的规模主要受上风侧可供沙源有效性和灌丛生长状况的控制,灌丛沙丘的出现是该区土壤风蚀和土地退化的主要标志。
Caragana microphylla shrub dune is the main type of sand accumulation in the ecotone between agriculture and animal husbandry in the northern foot of Yin Mountain in Inner Mongolia Plateau. Field surveys show that the shrub dunes are mainly distributed in the areas where cultivated land, alluvial fan leeward side and surrounding villages are located, and human activities are frequent. Based on the detailed measurements of the morphological parameters of the scrubland dune and the systematic observation of the dune and dune airflow in the typical plots on the leeward side of the arable land, it was found that the coverage of the dune and the deposition of sandstorms reduced in the direction of the wind, Kinetic roughness decreases in the direction of the wind; in the sand dunes, the wind profile tends to be complex from the top to the lee on the upwind slope. Among the parameters of dune morphology, there is a good power function correlation between sand dune height and horizontal scale, indicating that in the current wind and sand source environment, the scrub dune in this area is in an increasing stage, but its rate is less than horizontal expansion. The scale of the shrub dune in this area is mainly controlled by the availability of sand on the windward side and the growth of shrubs. The appearance of shrub dunes is the main indicator of soil erosion and land degradation in this area.