Biological cycling of Koelreuteria paniculata plantation microelements in Xiangtan Manganese Mine wasteland
Plants have been used to mitigate pollutant concentrations in contaminated soils.In order to understand and evaluate the possibility of Koelreuteria paniculata species in Phytoremediation,a study was conducted in an abandon manganese mine wasteland in Xiangtan to examine the characteristics of concentration,accumulation,spatial distribution and biological cycling of 8 microelements (Fe,Mn,Cu,Zn,Pb,Co,Ni,Cd) in a 5-year old Koelreuteria paniculata plantation,.The results showed that the concentration of 8 microelements in the plantation soils was in an order Fe＞Mn＞Zn ＞Pb＞Ni＞Cu＞Co＞Cd,and the concentration of Fe,Mn,Co and Cd were increased with soil depth.On the litterfall layer,the concentrations of all microelements were enriched except the elements of Mn and Co.The concentration of Mn and Co was decreased in both semi-decomposed and complete-decomposed litterfall parts.The concentration of microelements in different organs of Koelreuteria paniculata species was ranked as:Leaves＞Branch＞Fine root＞Bark＞coarse root＞Large root＞ Stump＞Stem and the concentration of 8 microelements were in the order of Mn＞Fe＞Zn＞Pb＞Cu＞Cd＞Ni＞Co.The total storage of 8 microelements in the plantation was 15.27kg/hm2,the storage of the microelements was the highest in branch and stem,which accounted for 54.2％ of the total storage of the microelements.The storage of microelements in organs was ranked as:Branch＞Stem＞Leave＞ Bark＞Stump＞Large root＞Coarse root＞Fine root.The annual absorption、annual retention and annual return amount of microelements were 5.26kg· hm-2· a-1,2.50kg· hm-2· a-1,and 2.75kg· hm-2· a-1 in the studied plantation,respectively.The utilization coefficient,cycling coefficient and recycling period were 2.39,3.14 and 11.20a,respectively.Our study indicated that Koelreuteria paniculata plantation had a high ability to absorb and enrich Mn,The plantations had high requirements of Mn for maintaining growth,a high intensity of cycle,and short turnover time.In addition,Koelreuteria paniculata plantation had a relative high ability to stabilize the nutrient contents and to adapt the changed environment,which provides benefit for maintaining forest productivity.The results suggested that Koelreuteria paniculata tree species could be selected as a prioritize tree species in phytoremediation in abandon manganese mine regions.
国家科技期刊平台
NSTL
万方数据
维普
