Repairation Of Five Species Of Herbaceous Plants To Lead (Pb)Pollution In Mining Soil

Since1990s, with the development of the global economy, thecourse of industrialization and urbanization had accelerated, thescale of Mineral mining and Metal smelting had enlarged, pollutantsof heavy metal had passed different way to soil, made the degree ofheavy-metal-polluted soils increasingly serious, caused a seriousthreat to the survival of humans and other biological environment.According to the first national pollution census bulletin showed,heavy-metal-polluted soils was one of the most prominentenvironmental problem in China, and the position was still seriously.Therefore, five species of herbaceous plants includingTaraxacum mongolicum, Poa annua., Lagopsis supine, Xanthiumsibiricum, Chenopodium glaucum were selected from Shanxiprovince to building a small simulation of heavy-metal-lead-pollutedsoils environment with different concentration of lead by artificial.To study the different concentrations of lead treatment on theinfluence of different plant biomass and root morphology and The fivekinds of plants in which plants to lead a better absorption ofenrichment, screened out hyperaccumulation plants of lead andadapt to repair local lead pollution soil plant, given the basistheoretical to pollution soil repair. The results as follows:(1) During the experiment: five species plants were grown normal, survival rate was very high, only a few plants survival ratewas80%, indicated the five species plants had better patience toheavy metal lead. The plant biomass of processing group were higherthan the control group, biomass of Poa annua. were the largest ineach processing group, and part of Poa annua. had been heading inthe end of the experiment. The root-top ratio of five species plantswere falling with the increase of concentration of lead, finally hadflat-lined, indicated that the absorption of root had been inhibited bylead(2)The influence of five species plants root morphology underdifferent lead processing: The total length, diameter, surface area andvolume of five species plants root all offered upgrade firstly thandescending latter tendency, and there was significant differencesamong the five species plants（P﹤0.05）in each processing group; thetotal length of Lagopsis supine was the shortest, the diameter,surface area and volume of Xanthium sibiricum was the smallest,Lagopsis supine followed, but the concentration of lead processingthat Lagopsis supine inhibited was higher than other four plants, itshowed the tolerance of Lagopsis supine root with heavy metal leadwas the strongest and more suitable for growth at lead pollution areathan other four plants.(3) The characteristics of five species plants for uptake,bioaccumulation and translocation under different lead processing:The content of Pb in above-ground biomass of each plants were allover1000mgkg-1at20000mgkg-1pocesssing group, particularly inLagopsis supine, it illustrated the highest content and reached to 5447.25mgkg-1. In the under-ground biomass, it showed the similartrend as the above-ground biomass that is the content of Pb were alsoreached1000mgkg-1at20000mgkg-1processsing group, themaximum content was13448.5mgkg-1in the Xanthium sibiricum. Thebiological concentration factor and translocation factor of Lagopsissupine were all the highest, so the results suggested that theLagopsis supine was a Pb hyperaccumulation plants, showed theLagopsis supine had strong ability of uptake, bioaccumulation andtranslocation to Pb. the others four plants have strong ability of Pbuptake, but the ability of bioaccumulation and translocation wereworse, hard to harvest, easy to secondary pollution, so don’t as thefirst choice plant to repair the soil of lead pollution.(4) To sum up, there were significant differences (P0.05) amongthe five species plants in the influence of root morphology, survivalrate and biomass. Lagopsis supine had strong ability of uptake,bioaccumulation, translocation and tolerance to Pb, Taraxacummongolicum, Poa annua., Xanthium sibiricum, Chenopodium glaucumwere relatively poorly, so Lagopsis supine as the repair plant of firstchoice for mining area of heavy metal lead pollution soil.