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Mining, heavy metal smelting brought a large number of heavy metal contaminated sites, not only occupy the land resources, and likely to cause pollution of the surrounding environment. Plant stable repair can achieve a variety of purposes, such as the stability of the tailings, pollution control, landscaping and vegetation recovery, which, in the heavy metal pollution on marginal land to grow non-food and energy plants, will become an emerging bio-energy production trends . In this study, the typical heavy metal pollution of marginal land Zhejiang Fuyang copper-zinc smelter surrounding heavy metal pollution The farmland and Anhui Tongling Yangshanchong the tailings pond as a test base to explore the use of lime, attapulgite, bentonite, zeolite, phosphate powder as a modifier venue The matrix nature improvement, planting demonstration energy plant research. The demonstration cultivated Miscanthus (Miscanthus floridulus), Di (Miscanthus sacchariflorus), sweet sorghum (Sorghum bicolor) and sugarcane (Saccharum officinarum) is an important raw material for the production of bio-ethanol. Silver grass (Miscanthus) in developed countries in Europe and the United States is often referred to as a \Barley root elongation toxicity test and available heavy metal (0.1molL-1 sodium nitrate extractable) chemical extraction based on the analysis of the test site to investigate, select representative samples of soil at the site, and to analyze soil at the site of the plant growth limiting factor, and targeted screening matrix modifier; screening improver demonstration energy plant cultivation demonstration biomass energy plants, the heavy metal content and soil available heavy metal content analysis, made the following findings: barley root elongation toxicity response test, evaluation lime, attapulgite, bentonite, zeolite, rock phosphate as the effect of the modifier. Valid state of most heavy metal content is low, heavy metal solubility is significantly reduced, wherein, Ca (OH) 2 is higher than 0.9% the amount of applied administered in the test site of the test soil, Ca (OH) 2 significantly increased the pH of the soil; At the limit of detection. With the increase in the Ca (OH) 2 the amount of applied, soil pH continues to rise, barley root length showed shortened after the first growth trend. Applied Ca (OH) 2 on the basis of applied attapulgite, bentonite, zeolite, rock phosphate, without significantly improving the results of the tested soil, but the right amount of rock phosphate as a long-term phosphate fertilizer is applied. The experimental analysis shows that, applied to the demonstration area test Ca (OH) 21% w / w, rock phosphate, 0.1% W / W as a modifier for the best. 2 in the Zhejiang Fuyang marginal heavy metal pollution of farmland demonstration area, applying conditioner Ca (OH) 2 and rock phosphate soil Cu, Zn valid state content showed a significant downward trend, but after the planting season energy plant, the analysis of the demonstration zone soil available accumulation of heavy metals affect the probability distribution of the soil available Cu, Zn were picked up, after the planting season energy plants still need to apply conditioner to inhibit the effective Cu, Zn content continue to grow in the coming year. Sugar cane, sweet sorghum, and vetiver planting season, biomass per unit area of ??sweet sorghum gt; sugarcane gt; vetiver. The cultivation of energy plants Zn patience studies have shown that the patience of the sugar cane is significantly higher than that of sweet sorghum. Cultivation of sugar cane and sweet sorghum juice quality analysis showed that the sap of sugar cane and sweet sorghum juice total sugar and reducing sugar percentage of the difference was not significant in all treatment areas; sap yield per unit area, sweet sorghum and sugarcane 2 times; The Zn content beyond the national food hygiene and safety standards (≤ 5 mg / l), exceeded the rate was 96.8%, and should not be as a beverage. The heavy metal content and enrichment capacity in the sugar cane, sweet sorghum, and vetiver there are some differences, which, taken away by the amount of Zn and Cd crop of energy plants per unit area of ??sweet sorghum gt; sugarcane gt; vetiver, while planting season energy plants taken away by the amount of Cu and Pb: Sugarcane gt; vetiver gt; sweet sorghum. 3. The Anhui Tongling marginal copper tailing demonstration area, the application improver January, the heavy metal content of surface tailings validity significantly reduced; significantly improve the pH after acidification regional tailings applied slaked lime; acidification regional rock phosphate applied part The experimental plot heavy metal validity elevated. Demonstration area planting season energy plants, the surface tailings acidification effective state heavy metal content of Cu, Zn content is still high, the need to add conditioner to reduce the toxic effects of the available heavy metals on the growth of energy plants for the coming year. The survival rate after cultivation of energy plants and growing statistics show that Di better than other plants tested (Di survival rate of 99.3%), reed, Miscanthus followed, Arundo donax adapt the worst. Season aboveground biomass energy plant cultivation analysis, the unacidified area aboveground biomass C District applied cow dung gt; District D (applied cow dung and rock phosphate); acidification region aboveground biomass Area B (applied cow dung, slaked lime and phosphate rock powder) gt; District (applied cow dung and slaked lime). The four energy of aboveground part of Zn, Cu, Pb and Cd uptake and accumulation capacity: Di gt; reed gt; five Mans gt; Luzhu. By kind of Tongling tailings pilot demonstration area for new settlers to plant diversity in the investigation and analysis show that tailings improvement and four gramineous energy plants artificially introduced species, new natural settle a total of 64 species of vascular plants, sub- belong to 25 families and 59 genera. Which annual or biennial herbs 57.8%; followed by perennial herb, accounting for 37.5%. Four processing zone species richness index, Simpson index and Shannon-Wiener diversity index showed D (applied rock phosphate District) gt; C (control area) gt; B (applied lime and rock phosphate District ) gt; the A (liming zone), homogeneity index vice versa. The analysis showed that the pH and available heavy metal content may be a limiting factor for new plants to settle.
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