Study on Plant Species Composition for Revegetatation at Zinc and Indium Mining Area

Silvicultural experiments including 10 species composition of 12 tested plant species were conducted in Zinc and indium mine waste accumulation site located in Dulong of Maguan county of Yunnan province from 2010 to 2013.Twelve tested plant species were Cupressus lusitanica,Alnus nepalensis,A.cremastogyne cv.yanshan,Ficus microcarpa var.pusillifolia,Celtis kunmingensis,Pinus elliottii,Buxus sinica,Ligustrum quihoui,Cajanus cajan,Neyraudia reynaudiana,Festuca arundinacea and Lolium perenne.Three years after field planting,the growth increments of 10 designed species composition were measured,and the soil nutritional status were analyzed as well.By considering the ecological status,site characteristics and the objectives of revegetation,four plant species with promising adaptability,afforestation survival rate and preserving rate were screened out,they were A.cremastogyne cv.yanshan,Cajanus cajan,A.nepalensis and Neyraudia reynaudiana.Combining A.cremastogyne cv.yanshan with Neyraudia reynaudiana or Cajanus cajan with Neyraudia reynaudiana,could speed up the positive succession,and form multilayer stand structure,with the survival rate over 95 % and preserving rate over 87 %.The average tree height and DBH of three years A.cremastogyne cv.yanshan were 4.79 m and 4.5 cm respectively,the average tree height and DBH of three years Cajanus cajan were 2.16 m and 2.8 cm respectively,the average height of Neyraudia reynaudiana was 2.18 m.The experimental results also indicated that at the initial stage of revegetation,choosing proper plant species and combining the species scientifically,the biodiversity could be maintained effectively,and the ideal community structure could be achieved,which therefore quite promising for the improve the soil fertility of the site.