| 摘要: |
| 利用海水人工湿地系统处理海水养殖外排水，分析了人工湿地对不同形态氮的净化效果，探讨了人工湿地表层基质酶活性变化及其对系统脱氮效果的影响。选取互花米草作为人工湿地植物，煤渣、珊瑚石和细砂作为人工湿地基质，实验期间连续进水，系统运行稳定。研究结果表明：海水人工湿地系统对氨氮（NH4-N）、亚硝态氮（NO2-N）、硝态氮（NO3-N）、总氮（TN）和可溶性有机氮（DON）去除效果显著，去除率分别为（99.6±0.7）%、（99.9±0.0）%、（98.2±2.0）%、（92.6±1.5）%和（86.1±4.8）%。人工湿地表层基质下行池脱氢酶、硝酸还原酶和脲酶的酶活性均高于上行池，下行池对污染物的去除效果更好。脱氢酶活性与海水人工湿地系统氨氮的去除有关；硝酸还原酶活性影响着海水人工湿地硝态氮的去除；脲酶活性与人工湿地总氮和硝态氮的去除存在明显相关趋势。下行池硝酸还原酶和脲酶的酶活性间具有显著相关性（r=0.76，P<0.05）。人工湿地微生物种类丰富，下行池微生物多样性高于上行池，植物根部微生物多样性最高，提高了系统脱氮的效率。上述研究结果将有助于阐明海水人工湿地系统中不同形态氮的迁移转化机理。 |
| 关键词: 人工湿地 海水养殖外排水 氮去除 酶活性 |
| DOI：10.11759/hykx20190121002 |
| 分类号:X55 |
| 基金项目:中国水产科学研究院基本科研业务费专项课题（2019CY0102）；国家自然科学基金项目（31101906）；国家科技支撑计划课题（2011BAD13B04）；山东省博士后创新项目专项资金（201703050） |
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| Enzyme activity in constructed marine wetlands |
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WU Jun-ze1,2,3, WANG Yan-yan2,3, LI Yue-yue2,3, ZHU Jia-xuan2,3, QU Ke-ming4,2,3, CUI Zheng-guo4,2,3
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1.College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China;2.Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs;3.Shandong Provincial Key Laboratory of Fishery Resources and Eco-Environment, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China;4.Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology(Qingdao), Qingdao 266071, China
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| Abstract: |
| Herein, a constructed marine wetland system was used to treat mariculture wastewater. The removal rates of different forms of nitrogen and substrate enzyme activity in the constructed wetland were explored. Spartina alterniflora was selected as the plant of the constructed wetland. The substrates were filled with cinder, coral rock, and fine sand. In four continuous experimental periods, the correlation trend between substrate enzyme activity and denitrification effects was investigated. Results showed that the removal rates of NH4+-N, NO2--N, NO3--N, TN, and DON were (99.6 ±0.7)%, (99.9 ±0)%, (98.2 ±2)%, (92.6 ±1.5)%, and (86.1 ±4.8)%, respectively. Nitrogen concentration decreased, and nitrogen removal rates significantly increased. Surface substrate activities of dehydrogenase, nitrate reductase (NR), and urease (UE) in the downstream pool were higher than those in the upstream pool. Nitrogen removal effects in the downstream were better than those in the downstream pool. Dehydrogenase activity was related to the removal of ammonia nitrogen in the constructed marine wetland. NR activity affected nitrate removal in the constructed wetland. Urease activity was significantly correlated with the removal of total nitrogen and nitrate in the constructed wetland. A significant correlation was observed between the activities of NR and UE in the downstream pool (r=0.76; P<0.05). Rich species of microorganisms were present in the constructed wetland. Microbial diversity was higher in the downstream pool than that in the upstream pool, and it was highest in plant roots, thereby improving nitrogen removal efficiency. These study results are expected to contribute to the research on the migration mechanism of different forms of nitrogen in constructed marine wetlands. |
| Key words: constructed wetland mariculture wastewater nitrogen removal enzyme activity |
