College of Life Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, PR China.
College of Life Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, PR China; School of History, Geography and Tourism, Shangrao Normal University, 401 Zhiming Road, Shangrao, 334001, PR China.
J Environ Manage. 2020 Jul 15;266:110607. doi: 10.1016/j.jenvman.2020.110607. Epub 2020 Apr 17.
The major targets of constructed wetlands (CWs) during wastewater treatment include achieving high-quality effluent and maintaining stable effluent quality. Plant species diversity can increase nitrogen (N) removal efficiency and improve effluent quality by decreasing the effluent N concentrations, including nitrate (NO-N), ammonium (NH-N) and total inorganic nitrogen (TIN) concentrations in CWs. However, the effect of plant diversity on the stability of effluent quality in response to perturbation in the form of an increased NH/NO ratio in influent has not been studied. This study conducted a microcosm experiment and assembled four plant species richness levels (1, 2, 3 and 4) and 15 species compositions by using 90 simulated CW microcosms to investigate the effect of plant diversity on the effluent N concentrations and their stability with an increase in the influent NH/NO ratio from 0:100 to 33:67 in the later stage of the experiment. The results showed that (1) plant species richness maintained a positive effect on effluent quality under an increased influent NH/NO ratio; (2) high species richness enhanced the stability of effluent water quality; (3) the presence of Phragmites australis in the community decreased the effluent TIN concentration and improved its stability under perturbation; and (4) the presence of Typha latifolia had a positive effect on N removal efficiency under perturbation. The establishment of communities with high plant species richness and proper species (such as P. australis) could simultaneously improve the effluent quality and stability in CWs for treating wastewater with increased NH/NO ratio.
人工湿地（CWs）在废水处理过程中的主要目标包括实现高质量的出水和维持稳定的出水质量。植物物种多样性可以通过降低出水中的氮（N）浓度，包括硝酸盐（NO-N）、铵（NH-N）和总无机氮（TIN）浓度，来提高氮去除效率并改善出水质量。然而，植物多样性对以进水 NH/NO 比增加形式的扰动下出水质量稳定性的影响尚未得到研究。本研究通过使用 90 个模拟 CW 微宇宙组装了四个植物丰富度水平（1、2、3 和 4）和 15 种组成，进行了微宇宙实验，以调查植物多样性对出水中 N 浓度及其稳定性的影响随着实验后期进水 NH/NO 比从 0:100 增加到 33:67。结果表明：（1）植物丰富度在增加的进水 NH/NO 比下对出水质量保持正效应；（2）高物种丰富度增强了出水水质的稳定性；（3）群落中存在芦苇（Phragmites australis）可降低扰动下的出水中 TIN 浓度并提高其稳定性；（4）在扰动下，香蒲（Typha latifolia）对 N 去除效率有积极影响。建立具有高植物物种丰富度和适当物种（如 P. australis）的群落可以同时提高处理 NH/NO 比增加的废水的 CWs 的出水质量和稳定性。
