| On the condition of global water resources being deficient day by day, irrigation by sewage has special significance. Especially in arid and lacking water region of the north of China, water resources deficiency has restricted economical development and influenced people living there. Therefore, sewage irrigation is imperative under the situation. Now, sewage has become heading water source for irrigation at outskirts of Chinese town.Sewage is used as stead irrigation water source and rich manure source, if it is reasonably utilized, which will take significant economical benefit for agricultural production and advancement. But sewage is unreasonably utilized in a majority of sewage irrigation regions, which has caused a series of environmental problems. Because they have complex chemical behavior and ecological effect and serious endangerment for human healthy sustainable development, heavy metals pollution caused by sewage irrigation has become one of focuses.The article took sewage irrigation region of Huafei river of Kaifeng city as sample, the author acquired heavy metals(mercury, lead, arsenic, cadmium, chromium, copper, zinc, nickel et al) contents of soil-wheat system by a lot of experiments. Following, the author analysed heavy metals pollution status of soil-wheat system by pollution index; analysed law of migration of heavy metals and correlation of heavy metals contents in soil-wheat system on the support of Microsoft Excel2000; analysed effect factors that wheat accumulates heavy metals from soil on the supports of SPSS10.0. Central conclusions are as follows:(1) Because of chronically irrigating by sewage, heavy metals have distinctly accumulated in soil at sewage irrigation region of Huafei river of Kaifeng city, cadmium and arsenic are main. The sample numbers that cadmium pollution index is more than 1 occupy the total numbers of soil samples 100%, the sample numbers that arsenic pollution index is more than 1 occupy the total numbers of soil samples 76.92%, the pollution index of copper, zinc, lead, chromium and nickel are all less than 1. Cadmium, copper, lead and arsenic are central pollutantsfor sludge in Huafei river, the sludge has not been used for agriculture.(2) Because of heavy metals accumulation in soil, heavy metals have distinctly accumulated in wheat. Cadmium pollution is serious in wheat for the seven heavy metals, the sample numbers that cadmium pollution index is more than 1 occupy the total numbers of wheat samples 100%; the pollution of chromium, copper, lead, arsenic, nickel is minor, the sample numbers pollution index more than 1 respectively occupy the total sample numbers 46.15%,38.46%,38.46%,15.38%,7.69%; zinc pollution is least, zinc pollution index is all less than 1.(3) Heavy metals entered into soil accumulate in the surface layer, the more depth of soil layer, the less content of heavy metals. The order of rate of heavy metals accumulation in the surface layer in profile 1 and profile 2 is arsenic>lead>nickel>cadmium>copper>zinc>chromium and arsenic>lead>nickel>cadmium>copper>chromium>zinc. Therefore, in comparison with other heavy metals entered into soil, arsenic is more easily accumulated.(4) The contents of heavy metals in soil and the distance between location where samples are collected and pollution source are different linear correlation at different location, the heavy metals that have linear correlation with the distance are different at different location. The content of copper and the distance are negative linear correlation at the north of fertilizer factory. The content of cadmium and the distance are positive linear correlation at the south of zinc-plant.Along the Huafei river, there are two dividing points between the fourth and the seventh collection position. From the first collection position, the ninth collection position to the fourth collection position, the contents of copper, lead, chromium, cadmium and zinc is increasing in the soil, the contents of arsenic and nickel is decreasing in the soil. From the twelfth c...
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