摘要
在传统潜流人工湿地中,因氧气扩散过低,导致DO长期处于较低水平.当湿地植物长期处于缺氧甚至厌氧环境时,可造成膜脂质过氧化及蛋白质和DNA损伤.由于生物炭投加至人工湿地利于空气扩散进入湿地床体,改善湿地内部环境,为此,本试验在温室内构建5组潜流人工湿地,研究生物炭对湿地植物菖蒲(Acorus calamus L.,AC)的影响特征和机制.结果表明,生物炭能够显著增加湿地中AC体内光合色素含量,光合作用被激励,利于植物体内可溶性蛋白(SP)的积累和植物生物量的增加,同时生物炭能加强谷氨酰胺合酶(GS)的活力,增强植物体内氨氮(NH_4^+-N)的代谢,进而增强AC的比吸收速率,利于AC吸收去除NH_4^+-N.AC是一类对缺氧条件具有显著抵抗能力的湿地植物,但湿地长期缺氧或厌氧能对AC体内造成膜脂被氧化的不良影响,但生物炭添加能够缓解AC体内超氧化物和过氧化物的积累,显著降低AC体内丙二醛(MDA)的含量.
Constructed wetlands（CWs） have high potential for wastewater treatment in developing countries because of their operational convenience and low maintenance costs.However,rapid accumulation of macrophytes in these wetlands,as a result of plant litter recycling,can lead to lower removal efficiencies.Periodic harvesting is consider to be the effective measure to maintain the wastewater treatment performance,and so a lot of harvested plant waste needs to be properly disposed of.However,in China,plant waste is usually used for agricultural burning and the greenhouse gas emissions bring adverse effects on the atmospheric environment.In the traditional subsurface flow CW,the dissolved oxygen（DO） concentration is low,resulting in long-term anoxic or anaerobic conditions,which will bring damages to plant body,such as membrane lipid peroxidation and protein and DNA damage.Generally,the addition of biochar to CWs is beneficial for aeration,and improves the internal environment of wetlands.Hence,the effects of plant biochar on the pollutant purification efficiencies in CWs were studied,and the role of biochar in macrophyte growth and antioxidative response was investigated.Based on the results of biochar application in agricultural fields,the harvested wetland plant straw was pyrolyzed to biochar at 500 ℃ under a dynamic high-purity nitrogen atmosphere.The wetland plant Acorus calamus L.（AC） was chosen for this study.The impact characteristics of biochar on AC were studied in five independent CWs built in a greenhouse,by combining the analyses of growth and antioxidative responses of plants.Results showed that the removals of ammonium（NH_4＋-N） and total nitrogen（TN） were significantly enhanced when biochar was added to CWs and that higher long-term nitrogen removal rates were achieved when the biochar application rate was increased.The photosynthetic pigment content in AC increased significantly with increasing biochar application rate.This stimulated photosynthesis and increased the soluble protein�
作者
黄磊
陈玉成
赵亚琦
肖广全
杨志敏
HUANG Lei;CHEN Yu-cheng;ZHAO Ya-qi;XIAO Guang-quan;YANG Zhi-min(College of Resources and Environment, Southwest University, Chongqing 400715, China;Chongqing Engineering Research Center of Rural Cleaning, Chongqing 400716, China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2018年第6期2904-2910,共7页
Environmental Science
基金
国家自然科学基金项目(51408493)
关键词
生物炭
潜流人工湿地
菖蒲
植物生长
氧化应激响应
biochar
subsurface flow constructed wetland
Acorus calamus L.
plant growth
antioxidative response
