| In this thesis, statistical works were performed on the data from the monitoring of arable lands of Wujiang during 2002-2004. The data included soil nutrients pH,SOC, total N,available P and toten contents of heavy metals of Pb, Cd, Hg, As and Cr of over 300 topsoils representing the typical soil species of the city. The effect of cultivation with different crops on soil nutrient status and heavy metal contents were discussed and the significance in soil environment quality changes were analysed. Finally, suggestions of soil environment protection for sustainabale developmengt of agriculture and socio-economics were given. The main results are as follows:1, Signifcant variation both with the analysed properties and with crop cultivations existed in the soils. Three types of elemental variation could be recognized. Available P was found in greatest vartion within all the samples while the pH being smallest; Those elements of Pb, Cd, As, Cr and Hg usually inputed under pollution wetre found in moderate variation with the CV being between 30%-50%. Variation of C and N largely depened on the soil and cultivation;2, Oevrallly, there had been ageneral trend of soil acidification, P accumulation and contamination of heavy metals in the soils of the city. This could be further supported by the quasi-normal distribution of the pH, available P and the heavy metals of all the samples. For the sils under various cultivations, soil acidification was found most prominent under fruit crop and vegetable cultivations,P accumulation most significant under vegetable and silk trees as well as other upland crops. Extensive pollution of heavy metals were found under vegetable crop cultivation with Pb and Cd contamination being predominant;3, The overall soil environmental quality as synthesized by the nutrient and heavy metal accumulation indice varied with the soils under different crop cultivations. Rice paddys wetre found better than the soils under cultivation crops other than rices for they...
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