Ministry of Agriculture and Rural Affairs Danzhou Scientific Observing and Experimental Station of Agro-Environment, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Haikou, 571101, China; Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
Ministry of Agriculture and Rural Affairs Danzhou Scientific Observing and Experimental Station of Agro-Environment, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Haikou, 571101, China.
Chemosphere. 2020 Feb;241:125059. doi: 10.1016/j.chemosphere.2019.125059. Epub 2019 Oct 4.
The climate-driven flooding poses a challenge for phytoremediation of contaminated soil, and the willow (Salix spp.) is a promising candidate coping with climate change and environmental pollution. In this study, uptake and accumulation of copper (Cu), zinc (Zn) and their bioavailability in the rhizosphere across the Salix clones under flooded versus non-flooded (control) conditions were investigated using a pot experiment. The tested Salix clones grew well without showing any toxic symptoms under non-flooded soil condition; in contrast, the clones showed 100% survival for long-term flooding with the development of hypertrophied lenticels and adventitious roots. There were wide clonal variations in biomass production and accumulation of Cu and Zn under flooded and non-flooded conditions. Flooded treatments dramatically decreased aboveground biomass across the Salix clones to different extents compared to the control. The non-flooded clones exhibited relatively high accumulation capacities of Cu and Zn in aerial parts. However, the flooded clones resulted in more substantial reductions in Cu and Zn accumulation in aerial parts, and most of Cu and Zn were limited in roots. EDTA-extractable Cu and Zn predicted well bioavailability of Cu and Zn to the Salix clones under the current condition. It was concluded that the Salix clones exhibited Cu and Zn phytoextraction traits (non-flooding) or phytostabilization traits (flooding), which provides a valuable insight into phytomanagement of contaminated soils by willows subjected to flooding stress.
受气候驱动的洪水对污染土壤的植物修复构成了挑战，柳树（Salix spp.）是应对气候变化和环境污染的有前途的候选物种。在这项研究中，使用盆栽实验研究了柳树无性系在水淹和非水淹（对照）条件下对铜（Cu）、锌（Zn）的吸收和积累及其根际生物有效性。在非水淹土壤条件下，测试的柳树无性系生长良好，没有表现出任何毒性症状；相比之下，在长期水淹条件下，无性系表现出 100%的存活率，伴随着肥大的皮孔和不定根的发育。在水淹和非水淹条件下，生物量生产和 Cu、Zn 的积累存在广泛的无性系变异。与对照相比，水淹处理极大地降低了柳树无性系的地上生物量。非水淹无性系在地上部分表现出相对较高的 Cu 和 Zn 积累能力。然而，水淹无性系导致 Cu 和 Zn 在地上部分的积累量大幅减少，大部分 Cu 和 Zn 局限在根部。EDTA 可提取的 Cu 和 Zn 很好地预测了当前条件下 Cu 和 Zn 对柳树无性系的生物有效性。结论是，柳树无性系表现出 Cu 和 Zn 的植物提取特性（非水淹）或植物稳定特性（水淹），这为柳树受水淹胁迫的污染土壤的植物管理提供了有价值的见解。
