| Atmospheric dust plays an important role in the biochemical and physical exchange on the ocean,atmosphere and land surface.Since the geological historical period,the exchange process has continued to this day.Some important pollutants with atmospheric dust as the transport carrier will accumulate in the atmosphere,water,soil and plants in different forms during the circulation of different ecosystems,Furthermore,the food chain poses a threat to human health.Cele County on the southern edge of Tarim Basin is an extremely arid area with serious wind and sand hazards.Studying the effect of natural atmospheric dust on Cele Oasis Soil will help to take effective protective measures,improve the soil quality of wind and sand soil,and reduce the adverse impact of dust hazards on vegetation growth and development,To improve the yield of farmland crops in Oasis and realize the local farmers to get rid of poverty and become rich,the theory has broad application prospects and important research value.Using the method of mathematical statistics,this paper makes an in-depth study on the near surface atmospheric dust fall,the temporal and spatial differentiation characteristics of physical and chemical properties and the impact on soil physical and chemical properties on different underlying surfaces inside and outside the oasis in Cele county.The research shows that:（1）The amount of atmospheric dust fall in Cele is higher in spring and summer and lower in autumn and winter.With the increase of altitude,the amount of atmospheric dust in Cele shows a decreasing trend.On the whole,from the quicksand land to the edge of the oasis,with the increase of the coverage of natural vegetation on the surface,the amount of dust fall also increases sharply.After entering the oasis,due to the blocking effect of tall and dense protective forest network,crops,houses and other buildings,the amount of dust fall in the near surface atmosphere shows a decreasing trend.Among them,the amount of dust fall in shiyizhakou is higher,which is due to the short reclamation period of shiyizhakou and no crop cultivation all year round,Due to the strong wind at the tuyere,the dust fall in the Gobi desert is low,which is due to the low vegetation coverage in the Gobi desert,the strong wind and the difficulty of fine particles settling.（2）Under different oasis processes,the dust falling in the atmosphere and the high sand material in the two layers of soil are composed of very fine sand,very coarse silt,fine sand and coarse silt,among which the very fine sand and very coarse silt are relatively large.There is little difference between the height of atmospheric dust fall and that of soil profile,and the particle size of surface soil is finer than that of atmospheric dust fall as a whole.（3）Under different oasis processes,the average particle size of atmospheric dust fall is is between 65.21 and 87.07μm,belonging to the category of very coarse silt and very fine sand.The average sorting coefficient is generally between 1.63 and 2.06,belonging to medium,medium poor sorting.The average soil particle size is between 59.14 and 83.29μm,belonging to coarse silt,very coarse silt and very fine sand.The average sorting coefficient is generally between 1.47 and 2.25,belonging to medium good sorting,medium and medium poor sorting.On the whole,the average particle size of atmospheric dust is slightly coarser than that of soil,the sorting property is not different from that of soil,the skewness tends to be finer than that of soil,and the peak state tends to be narrower than that of soil.（4）The fractal dimension of particle size of different underlying surfaces of atmospheric dust fall is between 1.41 and 2.30,the average value of fractal dimension of particle size is between 1.76 and 2.15,the fractal dimension of particle size of different underlying surfaces of soil is between 1.94 and 2.17,and the average value of fractal dimension of particle size is between 2.06 and 2.22.On the whole,the fractal dimension of atmospheric dust fall is smaller than that of soil,and the dispersion degree of fractal dimension of atmospheric dust fall is larger than that of soil,The fractal degree of atmospheric dust is poor and the self similarity is weak.The fractal degree of soil is good and the self similarity is strong.The fractal dimension value of0-20 cm soil layer is larger than that of 20-40 cm soil layer,the dispersion degree of fractal dimension of 0-20 cm soil layer is smaller than that of 20-40 cm soil layer,the fractal degree of0-20 cm soil layer is better,the self-similarity is stronger,the fractal degree of 20-40 cm soil layer is poorer,and the self-similarity is weaker.（5）The fractal dimension of atmospheric dust and soil was negatively correlated with average particle size and skewness（P<0.01）,and positively correlated with sorting and skewness（P<0.01）.The fractal dimension of atmospheric dust fall has a significant positive correlation with clay,very fine silt,fine silt,medium silt,coarse silt and very coarse silt（P<0.01）,a significant negative correlation with very fine sand（P<0.01）,a significant positive correlation with clay,very fine silt,fine silt,medium silt and coarse silt（P<0.01）,and a significant negative correlation with very fine sand and fine sand（P<0.01）.（6）The organic matter content of atmospheric dustfall is lower than that of soil.Under different oasis processes,except for Daxian station,the organic matter content of atmospheric dustfall is between 11.22 and 47.27g/kg,and the organic matter content of 0-20 th layer and20-40 th layer of soil is between 22.01-96.04 and 22.23-190.09g/kg,respectively.The content of ammonium nitrogen is lower than that of soil,and the contents of atmospheric dustfall and soil ammonium nitrogen are between 13.37-22.06 and 4.18-34.50mg/kg respectively.The content of available phosphorus is lower than that of soil,and the content of atmospheric dustfall and soil available phosphorus are between 14.89-69.05 and 6.50-21.36mg/kg,respectively.The content of available potassium is obviously higher than that of soil,and the contents of atmospheric dustfall and soil available phosphorus are between 19.82-128.33 mg/kg and 2.11-24.94mg/kg,respectively. |
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