长柔毛委陵菜两个种群对重金属富集和热值的影响

测定了生长在云南省金顶铅锌矿的北厂和跑马坪矿段的Zn超富集植物长柔毛委陵菜野外植株的Zn、Pb、Cd等重金属含量和热值特征,并分析了重金属和热值之间的相关性。结果表明,北厂种群的叶片、叶柄和根中Zn的含量分别达到6217.05、7679.86 mg.kg-1和4455.44 mg.kg-1,分别是跑马坪种群的3.2、2.4倍和2.2倍;北厂种群叶片、叶柄和根的Cd含量分别为170.17、242.51 mg.kg-1和244.45 mg.kg-1,分别是跑马坪种群的3.0、2.2倍和1.9倍;而跑马坪种群叶片、叶柄和根的Pb含量分别达到1042.49、829.27 mg.kg-1和2621.39 mg.kg-1,分别是北厂种群的1.2、1.0倍和1.2倍;土壤中重金属含量的不同是造成两个种群富集Zn、Pb和Cd差异的原因。长柔毛委陵菜两个种群对相同重金属的转运和生物富集能力无显著差异,其中对重金属的转运能力呈现ZnCdPb的关系。同时,两个种群的叶片、叶柄和根中的灰分含量和去灰分热值都没有显著差异,其中根部的灰分含量最低,都小于6%;北厂和跑马坪种群的所有部位的热值以叶片最高,其中去灰分热值分别达到19.03kJ.g-1和19.57kJ.g-1。Fe和Mn对长柔毛委陵菜的热值累积有促进作用。

Heavy metal accumulation and caloric value characteristics in two populations of Potentilla griffithii var. velutina

Concentrations of heavy metals and caloric values as well as their correlation relationship in two populations of Zn hyperaccumulator Potentilla griffithii var. velutina grown in two different sites, Beichang and Paomaping which located in Jinding Pb/Zn mining area, Yunnan Province, were analyzed. The results showed that in Beichang population, Zn concentration (mg kg-1 of dry weight) reached 6217.05 in leaves, 7679.86 in leafstalks and 4455.44 in roots and it was 3.2, 2.4 and 2.2 times of Paomaping population, respectively; Similarly, Cd concentration in Beichang population was 170.17, 242.51 and 244.45 mg kg-1 in leaves, leafstalks and roots, respectively, which was 3.0, 2.2 and 1.9 folds as much as those in Paomaping population, respectively. However, Pb concentration (mg kg-1, DW) in Paomaping population which got 1042.49 in leaves, 829.27 in leafstalks and 2621.39 in roots were a little higher than those in Beichang population. Data showed that the concentration of Zn, Pb and Cd in both Beichang and Paomaping population was related to the concentration of heavy metals in soil. There was no significant difference in capacity of heavy metal translocation and bioaccumulation between these two populations. Both of them showed the same heavy metals translocation capacities which followed by the order of Zn>Cd>Pb. These two populations had no significant difference in ash content and ash-free caloric values in plant tissues. Ash content in roots accounted for smallest part in whole plant, which was less than 6%. Whereas leaves showed the highest caloric values in whole plant, which ash-free caloric value was up to 19.03 and 19.57 kJ g-1 in Beichang and Paomaping population, respectively. In addition, energy storage of P. griffithii var. velutina was facilitated by iron and manganese.