基质改良对河岸带芦苇区冬季脱氮效果及土壤-植物化学计量特征的影响  

Effects of substrate improvement on nitrogen removal in winter and soil-plant stoichiometric characteristics in reed(Phragmites australis)area of a riparian zone

作　　者：付子轼[1,2] 刘福兴 王俊力[1,2] 乔红霞 毕玉翠[1,2] FU Zishi;LIU Fuxing;WANG Junli;QIAO Hongxia;BI Yucui(Shanghai Academy of Agricultural Science,Shanghai 201403,China;Shanghai Engineering Research Centre of Low-Carbon Agriculture,Shanghai 201415,China)

机构地区：[1]上海市农业科学院,上海201403 [2]上海低碳农业工程技术研究中心,上海201415

出　　处：《农业环境科学学报》2023年第1期166-176,共11页Journal of Agro-Environment Science

基　　金：上海市科委长三角科技创新共同体领域项目(21002410300);国家自然科学基金项目(41807397);上海市青年科技启明星计划项目(19QC1400700)。

摘　　要：为探究基质改良对亚热带地区河岸带芦苇区冬季脱氮效果和土壤-植物化学计量特征的影响,以河岸带土壤基质为对照,通过芦苇湿地模拟实验,系统探讨不同基质(砾石、砾石+生物炭、陶粒+生物炭、改性陶粒+生物炭)添加条件下,芦苇湿地的冬季脱氮效果,以及土壤和植物各器官中C、N、P含量及其化学计量比。结果表明:基质改良能够提高芦苇湿地冬季脱氮效果,添加砾石处理使NH_(4)^(+)-N去除率提高8.3个百分点(P<0.05),添加砾石+生物炭处理使TN和NH_(4)^(+)-N去除率均提高8.9个百分点(P<0.05)。基质改良能够增加土壤TC、TN和TP含量,其中,添加砾石+生物炭处理使三者含量均显著增加(P<0.05)。添加生物炭的3个处理均有利于根C固定和植物N吸收,添加陶粒+生物炭和改性陶粒+生物炭处理对植物生长具有促进作用。土壤-植物化学计量特征存在一定的相关性,且土壤与植物茎和根之间的关系更大;与植物相比,基质改良使芦苇湿地冬季脱氮效果更易受到土壤化学计量特征的影响。研究表明,适当的基质改良能够提高亚热带地区河岸带芦苇区冬季脱氮效果,增加土壤养分,促进植物生长。We explored the effects of substrate improvement on nitrogen removal in winter and soil-plant stoichiometric characteristics in the reed(Phragmites australis)area of a subtropical riparian zone in a reed wetland simulation experiment using the riparian soil substrate as the control.Wetland N removal in winter,C,N and P contents,and their stoichiometric ratio in soil and plant organs were determined following addition of different substrates(gravel,gravel+biochar,ceramsite+biochar and modified ceramsite+biochar).Substrate improvement enhanced N removal from the reed wetland in winter.Gravel addition increased NH_(4)^(+)-N removal efficiency by 8.3 percentage points(P<0.05).Gravel+biochar addition increased both TN and NH_(4)^(+)-N removal efficiencies by 8.9 percentage points(P<0.05).Substrate improvement increased soil TC,TN and TP.These increase were significant with gravel+biochar addition(P<0.05).The three treatments involving biochar addition were conducive to root C fixation and plant N absorption.Ceramsite+biochar and modified ceramsite+biochar addition promoted plant growth.There was a certain correlation between soil and plant stoichiometric characteristics,and the relationship between soil with stems and roots was greater.Compared with the effect of plant characteristics,N removal by reed wetlands in winter was more easily affected by soil stoichiometric characteristics under different substrate additions.These results conclude that proper substrate improvement can enhance N removal in winter,increase soil nutrients and promote plant growth in the riparian reed area of a subtropical zone.

关 键 词：基质 河岸带 芦苇湿地 氮 化学计量特征 

分 类 号：X173[环境科学与工程—环境科学] S154.4[农业科学—土壤学]