| Aibi Lake in Xinjiang province has become one of the largest sources of dust storms.Nabkhas commonly distributed in arid and semi-arid areas,are mounds composed of wind-borne sediment that traped by shrubs.The Tamarix nabkha which widely distributed in Aibi Lake,is main distribute on bayou and alluvial fan fringe of north-south piedmont.The Subject make Tamarix nabkha of Aibi Lake around as the main research object,by use geomorphology method,basis on inspecting and observing in the open country,testing the analytical means combining with the deposit size experiment,soil experiment and so on.Study on individual characteristics of Tamarix nabkha and important indicative significance of environment.Preliminarily clarify quantitative relation among morphology parameters of Tamarix nabkha,discuss the fertile islands effect and salinity island effect of Tamarix nabkha;Illustrate nabkha surface particle diameter,sorting coefficient,skewness,kurtosis and relationship among them.Reveal grain-size variation characteristics of Tamarix nabkha . Explore indicant environmental significance which important significance to forecast the arid area desertification developing trend.The conclusion as follows:(1)Tamarix nabkha morphometric parameter has fine correlativity,there is high correlation between long axis and short axis,among long axis,short axis and upwind slope length is high correlation.The plant height plays a major role in sandpile height and sandpile volume.(2)The soil PH of Tamarix nabkha in study area is relatively stable.The soil shows salinization and it is main of sulfate.Tamarix nabkha forms obviously fertile islands,salinity island and ion island.(3)The results show that very fine sands are dominant in Tamarix Nabkha surface sediments,it account for 34.60%,followed by the fine sand,it account for 21.90%,then is coarse silt,it account for 13.21%.The very coarse sand content is the least,that is account for 0.08%.The average diameter is 4.19Φ.The mean sorted index is 0.10Φwhich is belong to well-sorted and the slope top sort is the poorest.The coefficient of skewness is-0.39Φwhich is belong very negative skewness.This mean surface sediment of Tamarix Nabkha is main fine components.The mean kurtosis value is 1.44Φwhich is belongs to leptokurtic distribution,consequently wind action process is persistent and sort is well and it shows leptokurtic distribution.The average diameter showed excellent negative correlation to sorting and kurtosis.It shows that the lager the average diameter ,the better the sorting and the gentler the kurtosis.It presents high positive correlation between sorting and kurtosis,the better the sorting and the gentler the kurtosis.There are not significant positive correlation between sorting and skewness,it shows that he better the sorting and the sand trend to fine fraction.It had no correlation between the average diameter and skewness, between kurtosis and skewness.(4)The regional dynamic wind is one of the main factors which influence the grain size composition and spatial variability of Tamarix Nabkha..(5)The Tamarix nabkha of study area which widely distributed on bayou and alluvial fan fringe of north-south piedmont of Aibi Lake . Intersection of salinization,desalination and Aeolian action form the Tamarix nabkha.It was in stable stage on bayou and in decline stage on alluvial fan fringe.Due to the Aibi lake area shrink back,powerful wind and sufficient sand source,which the nabkha slowdown the process of desertification in short-term.The stable is temporary,if the shrub which is destroyed by human or environmental changes lead to plant declension the nabkha will be eroded into activation stage,which lead to ecological environment deterioration further.
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