School of Life Science, Nanjing University, Nanjing, 210093, People's Republic of China.
Environ Sci Pollut Res Int. 2021 Nov;28(44):62235-62245. doi: 10.1007/s11356-021-15036-5. Epub 2021 Jun 29.
To identify the effect of influent salinity on substrate selection, a study was conducted in pilot-scale surface flow constructed wetlands (SFCWs). Compared with gravel and sand SFCWs, soil SFCWs performed similarly or worse at low salinities, while at high salinities, soil SFCWs performed similarly or better in removal efficiency (RE) of salt, total nitrogen (TN), total phosphorous (TP), and chemical oxygen demand (COD). Soil generally increased macrophyte growth (especially at high salinity) in terms of biomass, leaf chlorophyll concentration, root activity, and root catalase and superoxide dismutase activities. A general decrease in bacterial α-diversity in the rhizosphere was observed at high salinity, while compared with gravel or sand, soil improved rhizosphere bacterial community stability at varying salinities. At high salinity, compared with that of gravel or sand, the soil support of macrophytes and rhizosphere microorganisms increased pollutant RE in SFCWs. This finding highlights the necessity of varying substrate selection in SFCWs with influent salinities for both increasing pollutant RE and reducing input cost, with soil recommended at high influent salinity.
为了确定进水盐度对基质选择的影响，在中试规模的表面流人工湿地（SFCWs）中进行了一项研究。与砾石和砂 SFCWs 相比，土壤 SFCWs 在低盐度下表现相似或更差，而在高盐度下，土壤 SFCWs 在去除盐度、总氮（TN）、总磷（TP）和化学需氧量（COD）方面的去除效率（RE）相似或更好。土壤通常会增加盐度（尤其是在高盐度下）条件下大型植物的生长（生物量、叶片叶绿素浓度、根系活力、根过氧化氢酶和超氧化物歧化酶活性）。在高盐度条件下，根际细菌的α多样性普遍下降，而与砾石或砂相比，土壤在不同盐度下提高了根际细菌群落的稳定性。在高盐度条件下，与砾石或砂相比，土壤对大型植物和根际微生物的支持增加了 SFCWs 中的污染物去除效率。这一发现强调了在 SFCWs 中根据进水盐度变化选择不同基质的必要性，以提高污染物去除效率并降低投入成本，建议在高进水盐度下使用土壤。
