| This study based on the reality that soil contamination by heavy metalsbecome more and more serious, chose Cr pollution as the research object to do acomprehensive investigation and study on vegetation and soil of a typical Cr pollutionarea—one industrial waste residue dump of Yima city, got to know the soil pollutionand Preliminary screen out some Cr enrichment plants, combined with culturing inwater and in soil screen out more trees that were perfect for the growth of Cr pollutionarea. Besides, this article studied the principles of assimilation and accumulation of Crby different parts in plants,and Cr on subcellular distribution and chemical form ofplants,for further study on mechanisms of molecular biology of heavy metal Crtolerance, accumulation and detoxification in higher plants, these studies provided thetheoretical and practical basis for repairing heavy metal polluted soil. The mainstudies are as follows:（1）the region was mainly polluted by Cr、Pb、Cu and Zn. Experimentalresults showed that there were significant differences among different metal, in order:Cr﹥Pb﹥Cu﹥Zn, Cr was the main pollution element. By Nemerow multi－factorindex method, the pollute level was region5(heavy)﹥region1(heavy)﹥region3(alert)﹥region4(safe). It held that despite of processing and control, the soilpollution was already exist around the industrial waste storage area, so the urgentneed was to deal with the pollution source.（2）The survey area was still at the initial－middle succession stage especiallyZone2, biological diversity and species richness was still inadequate.In the pollutionarea higher plants60species,belonging to24families,53genus, in the lnitial–mediumstage of the vegetation restoration, fundamental the plants were basically perennial、shallow－rooted and drought－tolerant, belong to herbaceous plantcommunity.Gramineae and Compositae were the main constructive species andsecondarily Chenopodiaceae、Rubiaceae and Selaginellaceae.It shows these familiescould more easily adapt to environmental pollution of Cr than others,especiallyArtemisia argyi H. Lév.&Vaniot of Compositae、Themeda japonica (Willd.) Tanaka、Setaria viridis (L.) P. Beauv. And Arthraxon lanceolatus (Roxb.) Hochst. ofGramineae，Selaginella sinensis (Desv.) Spring ofSelaginellaceae.There are31species of plant in CK,which belongs to19families and29genera, it was plantation community mainly Platycladus orientalis (L.)Franco, at later stages of community succession, belong to forest community.（3）There were Cr content in9kinds of plants was30times higher than Normalplants（CK）in tne heavy metal polluted soil. Comparison then could be taken to findthat Phragmites australis (Cav.) Trin. ex Steud.、Pennisetum alopecuroides (L.)Spreng.、Rumex crispus L. and Artemisia argyi H. Lév.&Vaniot could be used forthe bioremediation and ecological recovery of Cr polluted soils. The common trees ofHenan as Ailanthus altissima (Mill.) Swingle had great potentialities for pollutionabatement and ecological restoration.（5）With the concentration of Cr ion increasing, the Cr content of Platycladusorientalis (L.) Franco、Robinia pseudoacacia L.、Broussonetia papyrifera (L.)L’Hér. ex Vent.、Diospyros lotus L.、Populus tomentosa Carrière have gone upaccordingly, Cr mainly accumulated in root and phloem in plants, Mn mainlyaccumulated in the leaves of plants, Fe and Pb distributed uniformly in each part ofplants.（6）The sequence of Cr accumulation in leaves of Pennisetum alopecuroides (L.)Spreng.was cell walls﹥cytoplasm﹥plasmids≈mitochondria, Cr accumulation of eachform was arranged as F残﹥FHAc﹥FNacl≈FHcl﹥F乙醇≈F水. |
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