Xu Zhelun, Zhong Shanshan, Yu Youli, Li Yue, Li Chuang, Xu Zhongyi, Liu Jun, Wang Congyan, Du Daolin
School of Emergency Management, Jiangsu University, Zhenjiang 212013, China.
School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
Plants (Basel). 2023 Jul 1;12(13):2523. doi: 10.3390/plants12132523.
Invasive and native plants can coexist in the same habitat; however, the decomposition process may be altered by the mixing of invasive and native leaves. Heavy metal contamination may further alter the co-decomposition of both leaf types. This study evaluated the effects of two concentrations (35 mg·L and 70 mg·L) and three types (Pb, Cu, and combined Pb + Cu) of heavy metal contamination on the co-decomposition of leaves of the invasive tree L. and the native tree Laxm, as well as the mixed effect intensity of the co-decomposition of the mixed leaves. A polyethylene litterbag experiment was performed over six months. The decomposition coefficient of the two trees, mixed effect intensity of the co-decomposition, soil pH and enzymatic activities, soil bacterial alpha diversity, and soil bacterial community structure were determined. A high concentration of Pb and combined Pb + Cu significantly reduced the decomposition rate of leaves. A high concentration of Pb or Cu significantly reduced the decomposition rate of the mixed leaves. In general, leaves decomposed faster than leaves did. There were synergistic effects observed for the co-decomposition of the mixed leaves treated with combined Pb + Cu, regardless of concentration, but there were antagonistic effects observed for the co-decomposition of the mixed leaves treated with either Pb or Cu, regardless of concentration. A high concentration of Pb or Cu may increase antagonistic effects regarding the co-decomposition of mixed-leaf groups. Thus, heavy metal contamination can significantly affect the intensity of the mixed effect on the co-decomposition of heterogeneous groups of leaves.
入侵植物和本地植物可以在同一栖息地共存；然而，入侵叶片和本地叶片的混合可能会改变分解过程。重金属污染可能会进一步改变两种叶片类型的共同分解。本研究评估了两种浓度（35毫克·升和70毫克·升）以及三种类型（铅、铜和铅+铜组合）的重金属污染对入侵树种L.和本地树种Laxm叶片共同分解的影响，以及混合叶片共同分解的混合效应强度。进行了为期六个月的聚乙烯垃圾袋实验。测定了两种树木的分解系数、共同分解的混合效应强度、土壤pH值和酶活性、土壤细菌α多样性以及土壤细菌群落结构。高浓度的铅和铅+铜组合显著降低了L.叶片的分解速率。高浓度的铅或铜显著降低了混合叶片的分解速率。总体而言，L.叶片比Laxm叶片分解得更快。无论浓度如何，铅+铜组合处理的混合叶片在共同分解时都观察到协同效应，但无论浓度如何，铅或铜处理的混合叶片在共同分解时都观察到拮抗效应。高浓度的铅或铜可能会增加混合叶组共同分解的拮抗效应。因此，重金属污染会显著影响异质叶片组共同分解的混合效应强度。
