The Effects Of Lead, Zinc And Copper Pollution On Ruderal Communities In Shanghai

Soil is one of the most important environmental factors and it connects with other environmental elements closely. The medium cities, urban and rural area and the rural, sub-exurban and rural soil is pollutedby heavy metal pollution in China.Herb is a kind of plant type which holds strong environment adaptability in fast growing, and itmaintains the characteristics of higher sensitivity than shrub. Studying in the effect of soil heavy metals of herbaceous plant communities and herbs’response for the soil heavy metal pollution and enrichment of heavy metals to herbal provides more theoretical basis and practical significance.In this paper, choosing Chenshan botanical garden in Shanghai as the experimental place in 2000 m2.The size of sample plants isl0m*10m and adding lead, zinc, copper--the three kinds of common heavy metals in urban soil. Each sample setting four repeated group, four comparison (without adding heavy metals) and four pieces of three heavy metals mixed samples, the total are 20 samples. During the spring and autumn by investigating sample herbaceous community species composition, biomass, distribution and habitat factors, the analysis of the effect of three kinds of heavy metal of herbaceous plant communities, and survey samples within the party advantage above-ground and under-ground biomass, root system analysis and determination of mixed samples of heavy metals in herbal heavy metal content in the body of the dominant species, understand the herbaceous plants of the three kinds of heavy metal enrichment ability, herb combining its own characteristics of biology and ecology, analyzing the characteristics of the weed community and the relationship between the soil heavy metal, enrich the theory of urban ecology. Through summary analysis of the above research contents, summarized the main conclusions of this paper is as follows:(1)There are no significant differences in 20 different simulation samples of heavy metal contamination with soil PH, moisture content, total organic matter content, soil total nitrogen, total phosphorus content of soil physical and chemical properties such as index. The heavy metals in the experiment comply with the requirements of control variables. The experimental results of heavy metals analysis of the impact in herbaceous plants hold accuracy and persuasive.(2)The survey of total sample sare 40, which record 114 kinds of plant species in spring and autumn. Herbaceous plant species under different processing quantity differences in different season, the overall is still in most species, mixing heavy metal sample types at least.(3)Small samples have the above-ground biomass in spring and autumn, under-ground biomass and total biomass of the minimum value occurred in heavy metal to composite processing and happened with the zinc processing sample area-- the next maximum.(4)Small sample the above-ground biomass, under-ground biomass and total biomass of the minimum value occurred in heavy metal to composite processing, occurred within the zinc processing sample area, the maximum to do next in the spring and autumn.(5)Chenopodiumglaucum in the sample area of each biomass index are the highest, and significantly higher than heavy metal which is added to the same value of mixed samples of heavy metals to a minimum. Eleusineindica in zinc processing samples of all the indexes is the highest, higher than that of heavy metal which is added to the same values has no consistent rule in the sample area.(6) Chenopodiumglaucum’s morphological changes, including root total root length, total projection area, average diameter, total surface area, root volume, root number, the result is consistent with the biomass, the indicators lead to deal with the highest and are significantly higher than the results; Eleusineindica’s root part of the analysis results are not consistent with the biomass. Zinc processing under the indicators doesn’t show obvious superiority, and the goose grass for zinc showing resistance conclusion still need to discuss.(7)The 10 advantage species of herbaceous plants with underground part for heavy metal enrichment ability show the consistency, however the maximum and minimum data showed in different herbs. A preliminary comparison made in dominant species in the three kinds of metal enrichment ability and provided experimental basis for further selecting in repairing mental herbs.