The Selection Of Tree And Herbal Plant Species To Resist Pollution At Sanlidong Coal Gangue Land In Tongchuan

The accumulation of coal gangue can destroy landscape and contaminate the environment.Phytoremediation can reduce these negative effects. Therefore it is important to select the plants which canendure heavy metal pollution in coal gangue land. On the basis of sectionalized for the Sanlidong coalgangue land, the effects of metal pollution on the composition and diversity of plant was studied, and theability to assimilate and accumulate heavy metal of different plants was analyzed using both fieldinvestigation and laboratory analysis. There are mainly four conclusions:(1) The pollution of Cd is the most serious, the level of contaminate is2~5; the contaminations ofother heavy metal are relatively slight, the polluting level of Ni is1~2, the level of Pb and Cu is1. Thecomprehensive pollution of different sampling areas is the same as the pollution of Cd, the level is2~5.(2) There are28plant species in coal gangue land, which belong to13families and26genera. Amongall these plant, Cynodondactylon(Linn.)Pers., Setaira viridis(L.)Beauv, Cynodondactylon(Linn.)Pers.,Cynodondactylon(Linn.)Pers. and Artemisiagmelinii Web. Ex Ste have relatively wide distribution. Therelation between soil pollution and the plants growth distribution showed that the numbers of plant species,biomass, coverage and diversity index reduced with the increasing of the comprehensive pollution.(3) The ability for transferring and accumulating heavy metal of the herb plants showed that,Artemisiagmelinii Web. Ex Ste, Artemisia scoparia Waldst. et Kit., Heteropappus hispidus (Thunb.) Less.are the best plants to resist Cd and Ni pollution. Artemisiagmelinii Web. Ex Ste, Artemisia scoparia Waldst.et Kit. are best resistant to Mn and Cu pollution. Artemisiagmelinii Web. Ex St, Conyza canadensis (L.)Cronq．, Artemisia scoparia Waldst. et Kit. and Cynodondactylon(Linn.)Pers. are best resistant to Znpollution. Conyza canadensis (L.) Cronq．is best resistant to Cr pollution. By analyzing the comprehensivetransfer and accumulation coefficient, Artemisia scoparia Waldst. et Kit., Artemisiagmelinii Web Ex Ste,Conyza canadensis (L.) Cronq．and Heteropappus hispidus (Thunb.) Less. which can resist strongly toheavy metal pollution are selected as advantage herb plants.(4) The results from analysis of transferring and accumulating ability of different tree species forheavy metal showed that, Robinia pseudoacacia L. and Hippophae rhamnoides Linn. can used as thetolerance tree species to remediate contaminative soil which contains Mn, Zn, Cd, Ni and Cu pollution, andUlmus pumila L. is a better tree to tolerate Cd, Ni, Cu and Cr pollution. Ailanthus altissima is used as abetter tree to tolerate to Cr pollution. Periploca sepium Bung. is a better tree to tolerate Mn, Zn and Cr pollution. Lespedeza bicolor Turcz. is used as a better tree to tolerate to Cd, Ni and Cu pollution. Accordingto the comprehensive transfer and accumulation coefficient, Robinia pseudoacacia L., Ulmus pumila L. andHippophae rhamnoides Linn. are pollution-resistant dominant tree species for Phytoremediation.