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选择青海共和盆地威连滩沙地冲沟为研究区,通过野外调查,沉积物样品采集和分析,结合1982年航片和2006年快鸟影像数据,分析研究区地质历史时期风水交互作用的环境变化和沙地冲沟风水交互侵蚀的现代特征。结果表明:全新世初期,研究区由水成沉积环境逐渐过渡到风成沉积环境,并有小的沉积旋回,到了全新世中期,气候变得较温润,风沙活动减弱,风成沙逐渐生草成土,但弱砂质古土壤层较薄,从全新世晚期至今,风沙活动有所增强;冲沟形成后,沙地冲沟发生着风蚀水蚀交互作用。起伏的沟岸和弯曲的谷底发生风积,为流水侵蚀增加了沙物质。风沙流对冲沟的形成有再塑造作用。同时冲沟侵蚀也影响着风沙活动,每年冲沟侵蚀约达8.3×104 t泥沙,是沙丘不断增长的一个重要物源。冲沟的狭长地形,其“狭管效应”加大了风蚀作用,增强了风沙灾害天气。
The gully gully in Wei Lian Tan of Gonghe Basin in Qinghai Province was selected as the research area. Through the field investigation, the collection and analysis of sediment samples and the 1982 aerial photos and fast bird image data in 2006, the environment of the geo-historical interaction of geomantic omen Modern Features of Change and Mutual Corrosion of Gouges and Feng Shui in Sandy Land. The results show that during the early Holocene, the study area gradually transitioned from sedimentary environment of water sedimentation to aeolian sedimentary environment with a small sedimentary cycle. By the mid-Holocene, the climate became milder, the wind and sand activities weakened, However, the paleosol layer is thin, and the sandstorm has been enhanced since late Holocene. After the formation of the gully, there is a wind erosion and water erosion interaction in the sand gully. Fluctuated tidal flat and curved bottom of the wind plot, adding water for the erosion of sand material. Wind sand flow formation of a ditch reshaping effect. At the same time gully erosion also affects wind-blown sand activities. Each year gully erosion is about 8.3 × 104 t of sediment, which is an important source of sand dune’s continuous growth. Long narrow gully terrain, its “narrow tube effect ” increased the role of wind erosion, increased sand storm weather.