| The Changjiang river delta is located at the east coasts of China, where belong to Subtropical maritime monsoon climate, and it is the most sensitive and complex area of east China.Under the action of atmospheric circulation, particulate matters were trasported by paleo-winter monsoon and westlies to the Loess plateaus, East China plain respectively, including Changjiang river delta and Sea area, forming aeolian deposit, and recorded the process of paleo-environmental evolutions. Biside it, during the time of dust storm, winter monsoon transported dust materials from desert of Northwest and North area of China to East China and east areas by the action of Mongolia and Siberian high pressure, changing the Chemical and mineral compositons of aeolian dust of East China, and recorded the information of the dust sources and the intensity of monsoon. Comparative analysising of the physicochemical characteristics of atmospheric particle matters and aeolian loess is the new angle of view to study the material origin, and it can provide important reference data for the Changjiang river delta and even global paleo-climat changing research.In this paper, the atmospheric particle matter and aeolian loess of Changjiang river delta and the areas on the way of dust transporting were used as study objects, and studied the Physicochemical characteristics of atmospheric particle matter of dust storm and non-dust storm periods and aeolian loess in Changjiang river delta and the areas on the way of dust transporting on the aspects of concentration, cheminstry, color index, magnetic characters, mineral compositon, etc., and analyzed the similarities and differences of the physicochemical characteristics and the distan-origin indicating indexes and methods of atmospheric particle matters of dust storm and non-dust storm periods and aeolian loess. Through analysis by synthesis of abundance data, several main conclusions come into being: (1) The order of mass concentrations of different grain sizes-atmospheric particulate matters in Shanghai city is TSP> PM10>PM2.5.The order of mass concentrations of TSP, PM10and PM2.5from three different sampling points are Putuo>Qingpu>Minhang, Qingpu>Putuo> Minhang, Qingpu>Putuo>Minhang. The seasonal order of mass concentration of atmospheric particulate matters is that the autom and winter are higher than spring, the spring is higher than summer. The assessment of air quality shows that the environments of atmospheric particulate matters in shanghai city has no pollution from2009to2010, except for the slight pollution of three sampling points of Putuo, Qingpu and Minhang districts in Dec.2009. The percent of PM10is65-73%in TSP, and PM2.5is40-50%, therefore, the fine particle pollution is high and harmful to health of city residents. The main effect factors of mass concentration of air quality are climate, dust storm and orgnation's pollution controll. Their relationships are that lower temperature and humidity is match along with higher concentration, on the contrary, higher temperature and humidity is match along with the lower concentration. The dust storm event will make the mass concentration to increase obviously, and there will be more coarse particles in dust storm.(2) The order of element volume concentrations and their seasonal changes of atmospheric particulate matters are probably identical in Putuo, Qingpu and Minhang districts of Shanghai, which show that the element compositions of atmospheric particulate matters in these three districts are exactly similar. This indicates the same sources of the atmospheric particulate matters. The elements of Zn, Cu, Mn, Ni, Cr, Ti, Fe, Na are easy to be absorbed in coarse particles, and Ca, Mg, Si, Al in fine particles, Pb, Sr in both grain sizes particles.(3) The distributions of enrichment factors (EF) values of elements in atmospheric particulate matters from the three sampling points in Shanghai are identical, which shows that elements of Ni, Zn, Pb belong to anthropogenic pollutions, Sr, Cu, Mn, Cr, Ti, Ca, Al, Mg, Fe, Na belong to crust original materials. In the samples from the sampling points along aeolian dust transporting ways, the elements of Pb, Zn, Ni come from anthropogenic source pollutions, and the EF values of Sr, Cu, Cr, Ti, Ca, Na in them are higher than the one in atmospheric particulate matters of Shanghai, which indicates that part of these elements come from anthropogenic materials, part of them from crustal materials. The elements of Mg, Al, Mn, Fe, K are from crustal materials.The standarded major elements by UCC in dust storm, non-dust storm and loess show that, the advantage concentrations of major elements in dust storm dusts are more closed to them in loess than in non-dust storm dusts, which indicates that the material origin of the dust storm dust is indentical to the source of loess, which mainly come from the deserts in western China,only part of them come from located places. The chemical characteristic of rich Na, Mg but poor Si, Al and the Mg/Al ratio can be used as indexs to indicat far source materials.(4) The rare element patterns of dust storm dust from all sampling points are similar to loess's of northern China, however, the rare element patterns of non-dust storm dust from different places are obviously different with each other and are different with dust storm dust and loess. Most of the loess and dust storm samples fall in the same field of scatter diagram of (La/Yb)CH vs. LaCH. The Ce-La-Sm compositions of loess and dust storm in triangular plot are close to UCC that indicates the origin of dust storm dust is identical to loess, which is mainly crust original material. However, the Ce-La-Sm compositions of non-dust storm dusts are different with the dust storm dust, loess, UCC, which indicates the material origin of non-dust storm dust is different with the dust storm dust and loess, and the dusts mixed with non-crust original material. Therefore, the dust storm dust has the same origin with the northern loess. (5) From Oct.2009to Oct.2010, the seasonal variations of color indexes of atmospheric particulate matters from three sampling points are consilient with each other, the rightness and redness of atmospheric particulate matters increased with time lapes, yellowness increased obviously during the time of dust storm, and decreased during the time of non-dust storm. The color indexes of atmospheric particulate matters in spring from the Northern cities changes with time lapes, and its variation of yellowness has good correlation with atmospheric particulate matters from Shanghai, which indicate that the source region of atmospheric particulate matters in spring from different places are similar to each others.The characteristics of color indexes of atmospheric particulate matters during the time of dust storm fall in between the characteristics of non-dust storm and loess, which indicates that part of the materials in atmospheric particulate matters during the time of dust storm have the same source relation with the loess, part of the materials comes from artifical sources. Therefore, color indexes especially yellowness are the effective indexes of source region indicating for atmospheric particulate matters during the time of dust storm.(6) High χlf and SIRM values of TSP, PM10in period of dust storm infor that high concentrations of pollution were carried from Northern by dust storm dust. Low χlf and SIRM values of PM2.5indicates that the contamination elements are enriched in TSP and PMio-The pollution concentration of dust storm particulate matters from Northern cities is low, so the dust storm dust is clean. But during the long way of transportation, many anthropogenic pollutions were absorbed on the dust, χlf value is relatively higher in winter than other seasons, and the superparamagnetic particles do contribution to the values, which indicate that high mass concentration of atmospheric particulate matters in non-dust storm period are mianly fine grain particles.χARM and particle's mass concentration, elements'mass concentrations all maintain at high value in winter, which indicates the SD ferromagnetizm dominants magnetic minerals in atmospheric particulate matters, and the pollution material is easy to be absorbed in SD particles. The dust storm samples fall in the extended line of loess in χ1f-SIRM scatter diagram, and it's magnetic susceptibility is higher than loess's, which suggests that the loess and dust storm samples are dominated by ferrimagnetism minerals and incompleted anti-ferromagnetism minerals, the non-dust storm dust contents not only ferrimagnetism minerals and incompleted anti-ferromagnetism minerals, but also other magnetic minerals. The obvious correlation of χ1f,SIRM,and χARM between loess and dust storm dust reveals the similar sources of loess and dust storm dust. The χ1f and SIRM value of dust storm dust are higher than loess, which indicates that there are not only crust original materials,but also anthropogenic pollutions in dust storm dusts. Non-dust storm dusts are different with loess and dust storm dusts, and there is no clear correlation in χ1fχARM and SIRM-χARM scatter diagrams, which suggests that the atmospheric particulate matters are effected by other particles except for ARM'S contribution, and the main compositions of the atmospheric particulate matters are anthropogenic pollutions.(7) The main minerals in atmospheric particulate matters of shanghai and northern cities are Q,G,Cal, Dol, Hem, Alb, Clc, S, K, I, H1, Sd, Bio, Ms, etc. Mineral composition in atmospheric particulate matters changes in different periods. More kinds of minerals are found in autumn, winter samples and dust storm dusts, and less in non-dust storm of spring and summer samples.This seasonal changing discipline is similar with the particle concentration and elements'concentrations.The average percentage concentrations of Q, Ms, Bio, S, Clc in atmospheric particulate matters of dust storm period are greater than that of non-dust storm period, G, Cal, Dol, K, Sd, I in in atmospheric particulate matters of dust storm period are less than that of non-dust storm period. The mineral compositions of atmospheric particulate matters in dust storm period are closed to loess, which suggests the resemble material sources of them.Watching by scanning electron microscope (SEM), we find that the irregular atmospheric particulate matters from Shanghai are mainly mineral combinations, the regular particles in them are globular fire coal,the cotton shaped combinations are wee ellipsoidal vehicle exhuast. Researched by EDS, the dust storm samples contain elements of O, C, Si, Al, K, Ca, Fe, Mg, S, Na, Cl,etc., the non-dust storm samples contain elements of O,C,Si,Al, Mg, Ni, Na, Cl, Ca, S, Fe, K, ect. Excepting for a little anthropogenic pollutions, the result of mineral compostions of samples studied by EDS are similar with the result studied by XRD. The study results by EDS of TSP sampled from Nantong, Zhengzhou, Beijing, Xi'an in dust storm period show that the element compositions of samples from every sampling point are similar with each other. Therefore, the mineral compostions of these sampling points are limilar with the samples from Shanghai in dust storm period, which infor the source relation of these tow kinds of samples.(8) Using the method of Binary Logistic Regression to build chroma and magnetic mathematical models of atmospheric particulate matters of shanghai during dust storm and non-dust storm period. Using the method of Ash grey relation entropy to screen out the elements whose volume concentrations of atmospheric particulate matters during dust storm and non-dust storm period have closer relations with dependent variable y. These elements are Al, Si, Na, Mg, which will be used as independent variable, and to build Logistic Regression model. Seen from these three regressions, the regression coefficient of Yellowness (0.96) is the highest one among them, and the regression coefficient of the magnetic parameter χlf (0.003) take the second place, the last one is the regression coefficient of Al, Si (3.3*10-4). Therefore, if to indicate far source materials, Yellowness b is the excellent index,χlf is the good index, and volume concentrations of Al, Si are the reference indexs for us.These conclusions are mainly identical with the above paragraphs. In the future research, we should enhance sampling frequency, improve sampling methods, and get enough samples of atmospheric particulate matters and more accurate sampling data. Combining with the physicochemical characteristics of the atmospheric particulate matters, analyze the differences and relations between loesses from Changjiang river delta and the Northern China of the same period, and discuss the tracing index of far source materials using the method of "present being a key to past".
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