摘要
铅锌尾矿是一类重金属含量极高 ,对植物生长产生毒害的生境。盆栽实验的结果显示 ,香根草和百喜草在纯尾矿或由尾矿和垃圾组成的混合基质上都能生长 ,但植物的长势随基质中重金属含量的增加而减弱 ,其中香根草的生物量所受的影响比百喜草的更大 ,即百喜草有比香根草更强的重金属抗性。 2种植物体内的重金属含量高低均为 Zn>Pb>Cu,但二者对它们的富集能力大小分别是 ,香根草为 Zn>Cu>Pb,百喜草则为 Cu>Zn>Pb。香根草和百喜草的根系对 3种重金属都有较强的滞留效应 ,滞留率均在 50 %以上 ;其中香根草对重金属的滞留率又明显高于百喜草 ;而且 ,同一植物对不同的重金属的滞留率也明显不同 ,香根草对 Pb的滞留率最高 ,而百喜草对 Cu的滞留率显著高过对 Zn和 Pb。由于香根草的生物量明显大于百喜草 ,结果香根草对 Pb、Zn的吸收量比百喜草高。当用 2 5%的垃圾改良金属尾矿时 ,百喜草对重金属的吸收量即达最大 ;而香根草则在尾矿和垃圾各占 50 %的基质中吸收最多的重金属 ;因此 ,添加一定量的垃圾( 2 5%～ 50 %左右 )用于尾矿改良时 ,不仅能使尾矿得到更快的植被恢复与更高的植物修复效果 ,而且能使垃圾资源得到充分合理的利用。总之 ,当开展对金属尾矿的植被恢复时 ,可选择种植抗性强、覆盖快的百喜草 ,但如果?
Mine tailings are usually hostile to plant colonization,and also toxic to animals and man through the food chain.It has long been a highlight in the field of restoration ecology how to substantially mitigate the toxicity of adverse factors(e.g.heavy metals,infertility,acidity,etc.)and then to make plant colonization successfully in mine tailings.A greenhouse experiment was implemented for the purposes of evaluating:1)the phyto toxicity of lead/zinc mine tailings located in northern Guangdong Province,China,2)the growing performance of vetiver grass ( Vetiveria zizanioides Nash)and bahia grass( Paspalum notatum Flugge)in the mine tailings,and 3)the heavy metals uptake of both grasses from substrates of the mine tailings with different concentrations of heavy metals.The experiment was conducted with a method of pot cultivation undertaken in a glasshouse,which was ventilated and pervious to light.There were five treatments with foure duplicates for each treatment and they were arranged as follows:100%(w/w)mine tailings,75% tailings+25% domestic refuse,50% tailings+50% refuse,25% tailings +75% refuse,and 100% refuse.The most distinct characteristics of the mine tailings and the domestic refuse were high concentrations of heavy metals(including Pb,Zn and Cu)and organic matter,respectively.Seedlings of vetiver or bahia were planted into the pots treated with the above treatmentsthree tillers of same species for each pot and 20 pots(5 treatments×4 duplicates)for each species.Before plants were put into pots,the shoots and roots of vetiver were pruned to 30 cm and 3 cm,respectively,and one half of the leaves of bahia were removed and its roots also trimmed to 3 cm.After cultivation for 130 days,the height and tiller numbers of vetiver were measured,and then all plants were harvested and prepared for chemical analysis,including the respective contents of Pb,Zn,and Cu in roots and shoots of the two species. The following results were obtained:1) Both vetiver and bahia could survive in lead/zinc mine tailings,ref
出处
《生态学报》
CAS
CSCD
北大核心
2001年第7期1121-1129,共9页
Acta Ecologica Sinica
基金
国家自然科学基金( No:39870 1 55)
广东省自然科学基金( No:980 4 79
990 2 59)资助项目
关键词
香根草
百喜草
铅锌尾矿
生活垃圾
重金属
植物毒性
植被重建
vetiver grass( Vetiveria zizanioides Nash)
bahia grass ( Paspalum notatum Flugge)
lead/zinc mine tailings
domestic refuse
phyto toxicity of heavy metal
phytoremediation
revegetation
