School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, PR China; School of Energy and Environmental Science, Yunnan Normal University, 768 Juxian Street, Kunming, 650500, PR China.
School of Energy and Environmental Science, Yunnan Normal University, 768 Juxian Street, Kunming, 650500, PR China.
Environ Pollut. 2020 Nov;266(Pt 3):115259. doi: 10.1016/j.envpol.2020.115259. Epub 2020 Jul 23.
Heavy metal pollution is widespread, and has an increasing trend in some countries and regions. It can be easily accumulated in plants, leading to plant species loss and affecting plant community composition. Artificial restoration can conserve plant diversity in contaminated soils and accelerate the recovery of polluted ecosystems. The application of nitrogen (N) and phosphorus (P) is inexpensive and convenient, which can increase the resistance of plants to adversity and promote the growth of plants in heavy metal polluted soils. In order to examine the effect of N and P nutrition on the conservation of plant community, we conducted a comparison experiment in greenhouse using soil with low N and P concentration, and set five treatments: C (soil with no heavy metals and fertilizer addition), H (soil with heavy metals addition but with no fertilizer), HN (soil with heavy metals and N addition), HP treatment(soil with heavy metals and P addition), HNP treatment (soil with heavy metals, N and P addition). Our results showed that heavy metal pollution reduced plant species by 300%, and significantly decreased plant diversity (P < 0.05). N addition increased the richness of plant species and increased the dominance of Euphorbia peplus, but had no significant effect on plant diversity and community structure, while reduced the evenness of plant species. P addition of HP and HNP treatments restored plant species richness and increased plant diversity under heavy metal pollution. The plant community structures of these two treatments were more similar to that of group C. Compared with N addition, P addition had a better performance to restoring the species composition and relative dominance of plant communities. Our results provided a guidance for the restoration of plant communities and the conservation of plant species in low N and P concentration soils with the context of heavy metal pollution.
重金属污染广泛存在，并在一些国家和地区呈上升趋势。它容易在植物中积累，导致植物物种丧失，并影响植物群落组成。人工修复可以在污染土壤中保护植物多样性，并加速污染生态系统的恢复。氮（N）和磷（P）的应用既便宜又方便，可以提高植物对逆境的抵抗力，并促进重金属污染土壤中植物的生长。为了检验 N 和 P 营养对植物群落保护的影响，我们在温室中使用低 N 和 P 浓度的土壤进行了对比实验，设置了五个处理：C（无重金属和肥料添加的土壤）、H（添加重金属但无肥料添加的土壤）、HN（添加重金属和 N 的土壤）、HP 处理（添加重金属和 P 的土壤）、HNP 处理（添加重金属、N 和 P 的土壤）。我们的结果表明，重金属污染使植物物种减少了 300%，并显著降低了植物多样性（P<0.05）。N 添加增加了植物物种的丰富度，并增加了 Euphorbia peplus 的优势度，但对植物多样性和群落结构没有显著影响，同时降低了植物物种的均匀度。HP 和 HNP 处理的 P 添加在重金属污染下恢复了植物物种丰富度并增加了植物多样性。这两种处理的植物群落结构与 C 组更为相似。与 N 添加相比，P 添加在恢复植物群落的物种组成和相对优势度方面表现更好。我们的结果为重金属污染背景下低 N 和 P 浓度土壤中植物群落的恢复和植物物种的保护提供了指导。
