Research On Diversities Of Plants And Effects Of Soil Heavy Metals On The Vegetation In The Vicinity Of Secondary Metal Smelters In Huanshan Town Of Fuyang City, Zhejiang Province

Environmental pollution has become the concerned focus of modern society, in which the heavy metals pollution caused by the exploitation and utilization of environmental resources is one of the major sources of pollution. As a result, the management and ecological restoration to heavy metals polluted areas have become the immediate and austere task faced by our country.Phytoremediation developed in recent years is a kind of soil remediation technology which can produce better ecological benefits and has the long-term economic prospects, and has become the hotspot in the research fields of pollution ecology. The key of phytoremediation is the selection and utilization of plants (including pioneer plants, metal-tolerant plants and accumulators or hyperaccumulators) for restoring the heavy metals polluted areas.To provide some references to the selection of pioneer plants and metal-tolerant plants, accumulators or hyperaccumulators for the recovery of vegetation and phytoremediation in the heavy metals polluted areas, a series of field investigations on the vegetation had been carried out and the ecological adaptability of some plant species had been observed in the vicinity of secondary metal smelters of Huanshan town in Fuyang city, Zhejiang province.Based on the investigations of the vegetation and the collection of samples, effects of soil heavy metals on the floristic elements, frequencies of different species in different quadrats and patterns of dominate plant populations in herbaceous layer were researched. The results were as follows:1. The vascular bundle plants in these areas had 123 families, 328 genera and 464 species.The elements of floristics in these areas was affected by the decrease of the richness of the species caused by the pollution of heavy metal. The dominate families in the areas were Poaceae, Leguminosae, Asteraceae, etc.; the dominate genera were Polygonum, Lespedeza, Rosa, and the like;2. Through statistical analysis to the frequencies of species in the quadrats and comparison of the dissimilarity coefficient between the communities, the author discovered that: copper tolerance species might include: Imperata cylindrica var. major, Setaria viridis, Cynodon dactylon, Polygonum hydropiper, Conyza canadensis, Cocculus orbiculatus, Artemisia lavandulaefolia, Solanum nigrum, Paspalum distichum, Glochidion puberum etc.; Zinc tolerance species might include: Imperata cylindrica var. major, Setaria viridi, Arthraxon hispidus, Humulus scandens, Polygonum hydropiper, Kalimeris indica, Conyza canadensis, Artemisia lavandulaefolia, Solanum nigrum, Paspalum distichum, Glochidion puberum, etc.3. The results indicated that the species in the community were all clumped. However, they were different in clump intensity. The patterns were closely related to not only biological characteristics of each species, but also the ecological characteristics of them. It was better for the plant populations with medium clump intensity to adapt to the heavy metals polluted environment than the others. In the end, the author tabled a proposal that the plant populations with medium clump intensity were the top-priority in choosing the pioneer plants or accumulator for controlling the heavy metals pollution with phytoremediation.