巴丹吉林沙漠近40a风沙活动规律浅析

Based on the data of wind from 11 meteorological observation stations in recent 40 years, the paper analyzed the temporal and spatial distribution characteristics of resultant drift potential in the Badain Jaran Desert. The 84 sand samples were collected and analysed from three compound crescentic dunes developped on southeast part of The Badain Jaran Desert. Through the statistics and computation of wind data and the analysis of Grain Size over compound crescentic dunes in The Badain Jaran Desert, this paper analyzed the characteristics of the blown sand activities in in this area. The following viewpoints were obtained: 1　Most parts of The Badain Jaran Desert are dominated by northwest wind and sub－dominated by west wind, while prevailing wind in southeast part of The Badain Jaran Desert is southeast, different froms other places. 2 The Badain Jaran Desert is strongly zoned from its surounding meteorological observation stations. It has impressively high DP and RDP value. Except for Ding Xin Station in medium wind power environment, the left stations are all belongs to high wind－power districts. 3 From the seventies till now, the value of DP and RDP in The Badain Jaran Desert shows a decending trend except for the RDP value of Guai Zihu Station in the north. This trend indicates that the wind power for the moment of The Badain Jaran Desert is far lower than it in the seventies. 4 Adopting sand rose map for classification of wind environments in defferent parts of The Badain Jaran Desert, Ejinaqi is Narrow unimodal wind regimes, Ding xin, Bayinmaodao and Ayouqi districts obtuse bimodal and Guaizihu complex. 5 Resultant drift directions in most parts of the Badain Jaran desert are southeast, which indicates annual net sand in these areas drifted from the northwest to the southeast of the desert, which consists with the analysis results of grain size of predecessors. RDD in Ayouqi staion shows the net sand drifted from the southeast to the northwest in the recent 40 years, which may attribute to the reason that, the Badain Jaran desert lies in the zone influenced by both northwest and southeast wind, the southeast monsoon was strengthened and northwest wind became weaker than a former time. So, if sand mareria is sufficient, there are two different drift directions, namely two sorts of sand source, existed in Badain Jaran desert at least. 6 Based on analysis results of meteorologic data and grain size, blown sand activities is that, in most parts of Badain Jaran desert in the past 40 years, northwest wind transported net sand from the northwest part to the southeast part of The Badain Jaran Desert.And besides this, analysis of collected sand samples also shows that, in the southeast part of Badain Jaran desert, grain size do fined from southeast to northwest. Combining results of meteorologic data in the southeast part, it can infered that southeast monsoon took blown sand to the inner desert from its southeast part.