Effects And Effective Use Of Plants On Cu、Cr Form On Sewage Irrigated Soil

This paper takes a sewage irrigated soil in Shanxi province as the tested soil, and corn, sorghum, soybean, sunflower oil, rapeseed, sunflower, castor bean and peanut as tested corns that planted in the local growing corn. This research is about the content and distribution of Cr, Cu in soil and corns. The purpose of this paper is that select the corn which is tolerate heavy metals and low accumulated and suitable for the region to be planted. The results were as follows:(1)In the first region that next to the source on irrigation Cr content reached450.4mg/kg, Cu content reached541.04mg/kg, that have already exceed the level of national soil environment quality3standard(Cr:300mg/kg; Cu:400mg/kg). In the vertical profile of0-100cm Cr, Cu content was main enrichment in0-20cm. Cr, Cu content reduce gradually under20cm.(2)After planted different corns, Cr and Cu content in surface soil show decreasing trend and the lower soil reduce slowly. In the surface soil the most obvious of Cr and Cu is sunflower. Cr is a decrease of26.8%and Cu is25.1%.(3) After planted different corns, Exchangeable Cu content increased, and other forms Cr, Cu showed decreasing trend in sewage irrigated soil. And the effect of5types most obvious is sunflower, little effect is corn and sorghum.(4)The correlation coefficient of HCL (O.lmol/L) extraction available soil Cr, Cu and crops seeds were0.363and0.551, which reached significant and highly significant correlation. That can reflect the bioavailability well of soil Cr and Cu, suitable for being evaluation indexes as Cr and Cu pollution of lime soil.(5)A11of8kinds of corn, except sunflower leaves is strongest enrichment ability on Cu, other corns strongest enrichment ability to Cr, Cu is root. The most mobility from root to grain is castor, and the minimum is corn.(6)A11of the corns, chlorophyll, proline and peroxides content of sorghum was significantly lower than the other five crops. That means sorghum resistant of Cr and Cu is lower. (7) In addition to yield of peanut and rape slightly low, other corns that planted in the sewage irrigated area of corn yield is basically equivalent with non sewage irrigated area. It means in addition to peanut and rape, other corns yield is not affected by sewage irrigation.(8) The largest total biomass to Cr, Cu of8kinds of corns is sunflower, corn and castor. The least total biomass to Cr, Cu is peanut.Cr content in grain of sorghum, soybean and rape and Cu content in grain of sunflower, soil sunflower, rape have exceeded the national food hygiene standard (GB18406.1.2001), and is not fit for human consumption. In addition to Cu content of sunflower leaves reached45mg/kg and feed hygiene standard, seeds and leaves of other corns can be used as animal feed or biomass energy.