College of Landscape Architecture and Arts, Northwest A&F University, Yangling, 712100, People's Republic of China.
Environ Sci Pollut Res Int. 2019 Sep;26(26):26733-26747. doi: 10.1007/s11356-019-05827-2. Epub 2019 Jul 11.
Rainwater heavy metal contamination is a growing problem worldwide, which damages the environment and human health. A primary challenge of sponge city designers is selecting suitable plants capable of surviving the toxic metals present in city rainwater. The concept of a sponge city to tackle urban surface-rainwater flooding and related urban rainwater management issues was established by People's Republic of China in 2014. Therefore, we studied the ability of sponge city plants to accumulate heavy metals from rainwater. Ophiopogon japonicus (Linn. f.) Ker-Gawl., Carex heterostachya Bge., Cornus officinalis Sieb. et Zucc., Sedum spectabile Boreau., Typha orientalis Presl., Lythrum salicaria L., Fatsia japonica (Thunb.) Decne. et Planch., Ilex chinensis Sims., Rosa chinensis Jacq., and Buxus bodinieri Levl. were selected as test plants, and their ability to accumulate four heavy metals (lead [Pb], cadmium [Cd], copper [Cu], and zinc [Zn]) was compared. Growth response and heavy metal accumulation across different species were compared over a 28-day enrichment cycle. The results showed that (1) Plant growth responses to heavy metals were significantly different. The most tolerant to heavy metals was Lythrum salicaria and the least tolerant was Rosa chinensis. (2) Concentrations of the heavy metals differed among sponge city plant species. In general, the concentration of Zn was highest, followed by Cu, Cd, and Pb. (3) The accumulation content of the same metal in different test species was related to the bioconcentration factor of the metal and the plant biomass. At the end of the enrichment cycle, Ophiopogon japonicus had the largest accumulation content for Pb, Cu, and Zn, and Lythrum salicaria had the highest accumulation content for Cd. (4) Considering the growth responses of plants and their final accumulation of heavy metals after the enrichment cycle, we concluded that Lythrum salicaria, Typha orientalis, and Ophiopogon japonicus are suitable for use in sponge cities to restore heavy metal-contaminated rainwater.
雨水重金属污染是一个全球性的日益严重的问题，它破坏了环境和人类健康。海绵城市设计师面临的主要挑战之一是选择能够在城市雨水中存活的具有耐毒性的合适植物。2014 年，中华人民共和国提出了海绵城市的概念，以解决城市地表雨水洪泛和相关的城市雨水管理问题。因此，我们研究了海绵城市植物从雨水中积累重金属的能力。选取麦冬（Ophiopogon japonicus（Linn. f.）Ker-Gawl.）、异穗苔草（Carex heterostachya Bge.）、山茱萸（Cornus officinalis Sieb. et Zucc.）、八宝景天（Sedum spectabile Boreau.）、东方香蒲（Typha orientalis Presl.）、千屈菜（Lythrum salicaria L.）、八角金盘（Fatsia japonica（Thunb.）Decne. et Planch.）、枸骨（Ilex chinensis Sims.）、月季花（Rosa chinensis Jacq.）和黄杨（Buxus bodinieri Levl.）作为测试植物，比较了它们对四种重金属（铅[Pb]、镉[Cd]、铜[Cu]和锌[Zn]）的积累能力。在 28 天的富集中，比较了不同物种的生长反应和重金属积累。结果表明：（1）植物对重金属的生长反应差异显著。对重金属耐受性最强的是千屈菜，耐受性最差的是月季花。（2）海绵城市植物物种间重金属浓度存在差异。一般来说，锌的浓度最高，其次是铜、镉和铅。（3）不同测试物种对同一金属的积累含量与金属的生物浓缩系数和植物生物量有关。在富集中，麦冬对 Pb、Cu 和 Zn 的积累量最大，千屈菜对 Cd 的积累量最大。（4）考虑到植物的生长反应及其在富集中的最终重金属积累，我们得出结论，千屈菜、东方香蒲和麦冬适合用于海绵城市来修复重金属污染的雨水。
