CO_2浓度升高对三江平原湿地小叶章碳氮含量的影响  

Effects of Elevated CO_2 on Carbon and Nitrogen Contents of Calamagrostis Angustifolia in Wetland of Sanjiang Plain

作　　者：赵光影[1,2] 刘景双[1] 张雪萍[2] 王洋[1] 

机构地区：[1]中国科学院东北地理与农业生态研究所湿地生态与环境重点实验室,吉林长春130012 [2]黑龙江省普通高等学校地理资源与环境遥感重点实验室哈尔滨师范大学,黑龙江哈尔滨150025

出　　处：《水土保持通报》2013年第1期87-91,共5页Bulletin of Soil and Water Conservation

基　　金：中国科学院湿地生态与环境重点实验室开放基金"三江平原湿地枯落物混合分解特征研究"(WELF-2009-B-002);黑龙江省教育厅科学技术研究项目"CO2浓度升高对三江平原湿地典型植物的影响研究"(12511165);中国科学院知识创新工程重要方向项目"典型湿地物质循环过程及其环境效应研究"(KZCX2-YW-309);黑龙江省自然科学基金资助项目"集成空间数据挖掘技术的点轴开发空间结构与生态环境演变关系研究(C201022)";哈尔滨师范大学科技发展国家预研项目"寒区森林沼泽湿地DOC动态研究"(12XQG-02)

摘　　要：利用开顶箱薰气室(open-top chamber),设置正常大气CO2浓度和高CO2浓度(700μmol/mol)2个水平和不施氮(NN,0g/m2)、常氮(MN,5g/m2)和高氮(HN,15g/m2)3个氮素水平,研究CO2浓度升高对三江平原草甸小叶章碳氮积累的影响。结果表明,CO2浓度升高条件下小叶章植株总固碳量增加,不同氮水平下小叶章总固碳量分别增加19.3%(NN),24.4%(MN)和24.6%(HN),且根固定碳量占植株总体碳库比例均有不同程度的提高。CO2浓度升高降低了小叶章各器官氮含量,其中叶、茎氮含量以抽穗期降幅最大(14.4%和19.5%),根氮含量以腊熟期降幅最大(17.4%)。小叶章各器官N含量的降低是由于CO2浓度升高条件下植株生长加快引起的稀释效应所致。An experiment with treatments differing in nitrogen supply（0, 5 and 15 g/m^2） and CO2 level（360 and 700μmol/mol） with OTC（open top chamber） equipment was carried out to investigate the effects of ele- vated CO2 concentration on the carbon and nitrogen accumulation of Calarnagrostis angustifolia in freshwa- ter marsh of the Sanjiang Plain. Results showed that elevated COe concentration increased carbon fixation of plant by 19.3%, 24.4% and 24.6% under the NN, MN and HN treatments, respectively. Elevated CO2 concentration also had a great impact on the carbon allocation in different parts of Calarnagrostis angustifo- lia, as the carbon distribution in root increased to different degrees under all the nitrogen treatments. Elevat- ed CO2 concentration reduced the nitrogen content of Calamagrostis angustifolia apparatus. The largest de- crease in leaf and stem both appeared in heading period（14.4% and 19.5%）, while the decrease in root ap- peared in dough period （17.4%）. The decrease of nitrogen content in apparatus was due to diluting effect by plant speeding growth under elevated CO2 concentration.

关 键 词：CO2浓度 湿地 小叶章 碳氮积累 

分 类 号：X144[环境科学与工程—环境科学]