氨态氮浓度和收割频率对绿狐尾藻根系泌氧特性的影响  

Effects of ammonia nitrogen concentration and harvesting frequency on radial oxygen loss characteristics of Myriophyllum aquaticum

作　　者：黄鑫星 蒋家陆 罗沛 李红芳[1,2] 张树楠 刘锋[1] 何铁光[4] 肖润林 吴金水[1,2] HUANG Xin-xing;JIANG Jia-lu;LUO Pei;LI Hong-fang;ZHANG Shu-nan;LIU Feng;HE Tie-guang;XIAO Run-Lin;WU Jin-shui(Institute of Subtropical Agriculture,Chinese Academy of Sciences,Key Laboratory of Agro-ecological Processes in Subtropical Region,Changsha Research Station for Agricultural&Environmental Monitoring,Changsha 410125,China;University of Chinese Academy of Sciences,Beijing 100049,China;College of Resources and Environment,Huazhong Agricultural University,Wuhan 430070;Agricultural Resources and Environment Research Institute,Guangxi Academy of Agricultural Sciences,Nanning 530007,China)

机构地区：[1]中国科学院亚热带农业生态研究所,亚热带农业生态过程重点实验室,长沙农业环境观测研究站,湖南长沙410125 [2]中国科学院大学,北京100049 [3]华中农业大学资源与环境学院,湖北武汉430070 [4]广西壮族自治区农业科学院农业资源与环境研究所,广西南宁530007

出　　处：《江苏农业学报》2020年第5期1112-1118,共7页Jiangsu Journal of Agricultural Sciences

基　　金：国家自然科学基金项目(41701566);湖南省自然科学基金项目(2019JJ50705);中国科学院前沿科学重点研究项目(QYZDJ-SSW-DQC041)。

摘　　要：植物根系泌氧特性对人工湿地微环境的状态以及污染物去除至关重要。本研究采用室内培养试验,分析0~200 mg/L氨态氮和2种收割频率下的绿狐尾藻根系泌氧特性,并探究植物株高、单株生物量、根孔隙度等对根系泌氧特性的影响。结果表明,经过29 d的培养,在0 mg/L、50 mg/L、100 mg/L和200 mg/L氨态氮处理下绿狐尾藻根系泌氧速率分别为8.6μmol/(h·g)、14.1μmol/(h·g)、14.6μmol/(h·g)和7.7μmol/(h·g)。除培养第15 d外,50 mg/L和100 mg/L氨态氮处理的绿狐尾藻根系泌氧速率随培养时间的增加而逐渐增加。收割处理会降低绿狐尾藻根系泌氧速率,根系泌氧速率表现为:未收割对照>14 d收割一次处理>7 d收割一次处理,收割频率高的绿狐尾藻根系泌氧速率较低。适宜的氨态氮质量浓度及收割频率有利于植物生长和恢复,过高的氨态氮质量浓度或收割频率会降低植物根孔隙度和株高,从而减少根系泌氧速率。相关性分析结果表明,绿狐尾藻根系泌氧速率与其根孔隙度、株高和单株生物量显著正相关(P<0.01),说明根系泌氧速率取决于作物自身生长状态和根系特征。在湿地运行管理中,适当调节进水氮负荷和植物收割频率有利于优化植物生长状况和根系泌氧特性,从而改善湿地环境。The root radial oxygen loss characteristics of plants are important for the state of microenvironment and pollutant removal in constructed wetlands.In this study,an indoor incubation experiment was used to explore the radial oxygen loss characteristics of Myriophyllum aquaticum under the treatments of 0-200 mg/L ammonia nitrogen and two harvesting frequencies,and the effects of plant height,biomass of single plant and root porosity on the radial oxygen loss characteristics were analyzed.The results showed that after 29-day incubation,the radial oxygen loss rates of M.aquaticum treated with 0 mg/L,50 mg/L,100 mg/L and 200 mg/L ammonia nitrogen were 8.6μmol/(h·g),14.1μmol/(h·g),14.6μmol/(h·g)and 7.7μmol/(h·g),respectively.Expect for the 15th day of cultivation,the radial oxygen loss rate of M.aquaticum under 50 mg/L and 100 mg/L ammonia nitrogen treatments gradually increased with the increase of culture time.The rate of radial oxygen loss of M.aquaticum was decreased under harvesting treatment,and the radial oxygen loss rate followed the order of the non-harvesting>harvesting once every 14 days>harvesting once every seven days.The lower radial oxygen loss rate was observed in the higher harvesting frequency treatment.These results indicated that proper ammonia nitrogen concentration and harvesting frequency were conducive for plant growth and recovery.Too high ammonia nitrogen concentration or harvesting frequency could reduce the root porosity and plant height,thus reducing the rate of radial oxygen loss.Correlation analysis results indicated that the radial oxygen loss rate of M.aquaticum had a significantly positive correlation with root porosity,plant height and biomass of single plant(P<0.01),showing that the rate of radial oxygen loss depended on plant growth condition and root characteristics.Adjusting the influent nitrogen load and plant harvesting frequency is beneficial to optimize the plant growth status and radial oxygen loss characteristics and improve the wetland environment during the operat

关 键 词：根系泌氧 氨态氮 收割频率 绿狐尾藻 

分 类 号：X171[环境科学与工程—环境科学] X52