{"title":"Purification Efficiency of Two Ecotypes of Wetland Plants on Subtropical Eutrophic Lakes in China","authors":"Yingmo Zhu, Kangning Shu, Ke Yang, Zhe Chen","doi":"10.1007/s13157-024-01787-7","DOIUrl":null,"url":null,"abstract":"<p>The accelerated eutrophication rate of (sub)tropical lakes is a major environmental problem. Constructed wetlands are considered as an effective method to purify water bodies. However, the removal rate of nitrogen (N), phosphorus (P) and other nutrients by wetland vegetation is quite different, and the continuous observation of plants and water ecosystems is required. In this study, the growth curves of two subtropical wetland plants, <i>Phragmites australis</i> and <i>Zizania caduciflora</i>, and their absorption effects on N and P in constructed wetlands were studied. The results showed that the growth curves of the two wetland plants were similar, reaching the biomass peak in July to August, and the cumulative absorption of N and P by plants had the same trend with the change of biomass. The N and P concentration of plants reached the peak in March to April, with higher concentration in <i>Phragmites australis</i> than that of <i>Zizania caduciflora</i>. At the end of the growing season, i.e. around October 20, the accumulated absorption of N and P by plants reached the maximum, which was the optimal time for harvest of subtropical wetland plants. Thereafter, the residues of plant litter entered the water, causing the recovery of N and P concentration in the water body, therefore affected the purification function of wetland. There is a strong correlation between the water purification efficiency and plant growth. With the increase of biomass, N and P accumulation in <i>Phragmites australis</i> and <i>Zizania caduciflora</i>, the N, P content and chemical oxygen demand (COD) in the water of wetland showed a significant decreasing trend. The removal rates of N, P, COD and suspended substance (SS) in the constructed wetlands with <i>Phragmites australis</i> and <i>Zizania caduciflora</i> as the main plants were 95%, 96%, 82% and 86%, respectively. In general, the purification capacity of <i>Phragmites australis</i> is slightly higher than that of <i>Zizania caduciflora</i> and precipitation had positive effects on the pollutants concentration of wetland water. The results provide scientific basis for plant selection and management of subtropical constructed wetlands.</p>","PeriodicalId":23640,"journal":{"name":"Wetlands","volume":"258 1","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2024-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Wetlands","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1007/s13157-024-01787-7","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The accelerated eutrophication rate of (sub)tropical lakes is a major environmental problem. Constructed wetlands are considered as an effective method to purify water bodies. However, the removal rate of nitrogen (N), phosphorus (P) and other nutrients by wetland vegetation is quite different, and the continuous observation of plants and water ecosystems is required. In this study, the growth curves of two subtropical wetland plants, Phragmites australis and Zizania caduciflora, and their absorption effects on N and P in constructed wetlands were studied. The results showed that the growth curves of the two wetland plants were similar, reaching the biomass peak in July to August, and the cumulative absorption of N and P by plants had the same trend with the change of biomass. The N and P concentration of plants reached the peak in March to April, with higher concentration in Phragmites australis than that of Zizania caduciflora. At the end of the growing season, i.e. around October 20, the accumulated absorption of N and P by plants reached the maximum, which was the optimal time for harvest of subtropical wetland plants. Thereafter, the residues of plant litter entered the water, causing the recovery of N and P concentration in the water body, therefore affected the purification function of wetland. There is a strong correlation between the water purification efficiency and plant growth. With the increase of biomass, N and P accumulation in Phragmites australis and Zizania caduciflora, the N, P content and chemical oxygen demand (COD) in the water of wetland showed a significant decreasing trend. The removal rates of N, P, COD and suspended substance (SS) in the constructed wetlands with Phragmites australis and Zizania caduciflora as the main plants were 95%, 96%, 82% and 86%, respectively. In general, the purification capacity of Phragmites australis is slightly higher than that of Zizania caduciflora and precipitation had positive effects on the pollutants concentration of wetland water. The results provide scientific basis for plant selection and management of subtropical constructed wetlands.
期刊介绍:
Wetlands is an international journal concerned with all aspects of wetlands biology, ecology, hydrology, water chemistry, soil and sediment characteristics, management, and laws and regulations. The journal is published 6 times per year, with the goal of centralizing the publication of pioneering wetlands work that has otherwise been spread among a myriad of journals. Since wetlands research usually requires an interdisciplinary approach, the journal in not limited to specific disciplines but seeks manuscripts reporting research results from all relevant disciplines. Manuscripts focusing on management topics and regulatory considerations relevant to wetlands are also suitable. Submissions may be in the form of articles or short notes. Timely review articles will also be considered, but the subject and content should be discussed with the Editor-in-Chief (NDSU.wetlands.editor@ndsu.edu) prior to submission. All papers published in Wetlands are reviewed by two qualified peers, an Associate Editor, and the Editor-in-Chief prior to acceptance and publication. All papers must present new information, must be factual and original, and must not have been published elsewhere.