摘要
为查明不同水生植物吸收地表水中氮磷能力的差异及其机理,采用模拟沟渠试验和盆栽试验,研究了8种水生植物地表水中氮磷吸收能力的差异,并选择氮磷吸收能力差异较大的水生植物品种,进一步探讨了根系生理特性及底泥微生物量变化。结果表明:种植水生植物后沟渠水中氮磷浓度明显减少,供试8种水生植物中以海寿花、狐尾藻、珍珠梅、茭白、再力花的生物量大,养分吸收量多,沟渠水中养分减少也相对明显;种植水生植物后相对于不种植物的沟渠水中养分残留减少比例分别为,总氮22.4%~44.0%、铵态氮24.5%~36.8%、硝态氮13.6%~51.6%、总磷15.6%~34.6%、水溶性磷26.3%~41.3%;氮磷吸收能力强的水生植物与其具有更强的根系活力、更多伤流量以及更高的伤流液养分浓度有关,但并不是某一种植物的以上指标均有优势,茭白的根系活力强、伤流量多,狐尾藻、海寿花、珍珠梅的伤流液中氮磷浓度较高;沟渠水中氮磷减少比例较大的水生植物底泥中微生物总数、硝化细菌和反硝化细菌数、微生物量碳氮磷较高,反之则较低。
In order to find out the difference in absorbability of different aquatic plants on nitrogen（N）and phosphorus（P）existing in surface water,and even to explore its mechanism,the simulated ditch experiment and pot experiment were conducted using 8 different aquatic plants.And the plants with great difference on absorbing N and P were selected to make further exploration on root physiological characteristics and microbiological changes of sediment.The results showed that the concentrations of N and P in ditch water decreased significantly after planting aquatic plants,among 8 aquatic plants,the greater biomass was observed in Pontederia cordata,watermifoil,Sorbaria sorbifolia,Zizaniaand thalia dealbata,which could absorb more nutrients,resulting in consequently,the decreased nutrients in ditch water.Compared with the treatment of no aquatic plants,nutrient residual in ditch water decreased significantly,total N decreased by22.4%~44.0%,ammonium nitrate decreased by 24.5%~36.8%,nitrate decreased by 13.6%~51.6%,total P decreased by 15.6% ~34.6% and water-soluble P decreased by 26.3% ~41.3%,respectively.Aquatic plants could absorb more nutrients was due to their stronger root activity,more xylem sap or higher SAP nutrient concentration.But these advantages could not exist in one specific aquatic plant,for example,Zizania had the stronger root activity,while the N and P concentrations in xylem sap were higher in watermifoil,Pontederia cordata and Sorbaria sorbifolia.In the ditch water planted aquatic plants,where the decreased proportions of N and P were larger,the total number of microorganisms,nitrobacteria and denitrifying bacteria,even the microbial biomass C,N and P were also higher,and vice versa.
作者
李旭霞
荣湘民
谢桂先
张玉平
严红星
宋海星
LI Xuxia, RONG Xiangmin, XIE Guixian, ZHANG Yuping, YAN Hongxing, SONG Haixing(College of Resources and Environmental Sciences, Hunan Agricultural University, Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, National Engineering Laboratory of Soil and Fertilizer Resources Efficient Utilization, Hunan Provincial Key Laboratory of Farmland Pollution Control and Agricultural Resources Use, Hunan Provincial Key Laboratory of Plant Nutrition in Common University, Chanszsha 41012)
出处
《水土保持学报》
CSCD
北大核心
2018年第1期259-263,共5页
Journal of Soil and Water Conservation
基金
湖南省重点研发计划项目(2016JC2030)
国家科技支撑计划项目(2014BAC09B01-01)
关键词
水生植物
生态拦截
微生物量
根系生理特性
aquatic plants
ecological interception
microbial biomass
root physiological characteristics
