长白山园池湖岸湿地生态系统碳氮储量沿环境梯度空间分异规律  

Spatial differentiation law of carbon and nitrogen storage along the environmental gradient of Yuanchi lakeshore wetland ecosystems in Changbai Mountain of northeastern China

作　　者：孙梓淇 牟长城[1] 王婷[1] 李美霖 王文婧 Sun Ziqi;Mu Changcheng;Wang Ting;Li Meilin;Wang Wenjing(Center for Ecological Research,Northeast Forestry University,Harbin 150040,Heilongjiang,China)

机构地区：[1]东北林业大学生态研究中心,黑龙江哈尔滨150040

出　　处：《北京林业大学学报》2024年第8期34-46,共13页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(31370461)。

摘　　要：【目的】探究湖泊沿岸湿地生态系统碳氮储量沿湖岸至高地的空间分异规律及形成机制,将有助于减少湿地碳储量估算的不确定性。【方法】采用相对生长方程、碳/氮分析仪,同步测定长白山园池沿湖岸至高地环境梯度依次分布的6种沼泽类型(芦苇沼泽L、草丛沼泽C、杜香沼泽D、落叶松泥炭藓沼泽LN、落叶松藓类沼泽LX、落叶松苔草沼泽LT)的生态系统碳、氮储量(植被和土壤)及其相关环境因子(水位、水位波动幅度、土壤有机质、全氮和全磷等),揭示其空间分异规律及其形成机制。【结果】(1)植被碳、氮储量(2.17~69.98 t/hm^(2)和0.058~0.940 t/hm^(2))沿湖岸至高地环境梯度均呈递增规律(LT≈LX>LN>D>C>L),且均以优势植被层占主体地位(73.72%~93.37%和71.57%~85.24%);(2)土壤碳、氮储量(67.45~243.21 t/hm^(2)和2.44~13.53 t/hm^(2))沿该环境梯度呈阶梯式递减规律(L>C>D≈LN>LX≈LT)且其碳储量垂直空间分异存在先恒定后递减(L)、先增后降(C、D和LN)和递减(LX和LT)3种类型,其氮储量垂直空间分异与碳储量基本一致(仅C和LX略有不同);(3)生态系统碳、氮储量(122.20~245.38 t/hm^(2)和3.31~13.58 t/hm^(2))沿该环境梯度分别呈先降低后恒定型或阶梯式递减型变化规律,且其土壤碳、氮储量占比呈递减趋势(50.27%~99.11%和73.48%~99.57%),而植被碳、氮储量占比却呈递增趋势(0.89%~49.73%和0.43%~26.52%);(4)生态系统碳储量在湖岸至高地水分环境梯度的下、中、上部生境地段依次受水位促进、水位抑制和水位波动幅度抑制,而氮储量在相应生境地段上依次受水位促进、水位波动幅度抑制和土壤全氮促进。【结论】园池沿岸湿地生态系统碳氮储量沿湖岸至高地水分环境梯度存在明显的空间分异规律,且其形成机制为微地形引起的水位梯度和植被类型分布决定着各沼泽类型的碳氮储存能力,故准确测定湖岸带各沼泽类型碳氮储�[Objective]Exploring the spatial differentiation and formation mechanism of carbon and nitrogen storage in wetland ecosystem along the lakeshore to the highlands will help to reduce the uncertainty of wetland carbon storage estimation.[Method]The ecosystem carbon and nitrogen storage(vegetation and soil),and related environmental factors(water level,water level fluctuation amplitude,soil organic matter,total nitrogen and total phosphorus,etc.)of six plant communities(L-Phragmites australis swamp,C-tussock swamp,D-Ledum palustre swamp,LN-Larix olgensis-Sphagnum magellanicum swamp,LX-Larix olgensis-moss swamp and LT-Larix olgensis-Carex schmidtii swamp)distributing along the lakeshore to the highland environmental gradient were simultaneously determined by relative growth equation and carbon/nitrogen analyzer method,to reveal its spatial differentiation law and its formation mechanism.[Result](1)The carbon and nitrogen storage(2.17-69.98 t/ha and 0.058-0.940 t/ha)of the vegetation increased progressively along the environmental gradient from lakeshore to upland(LT≈LX>LN>D>C>L),in which the dominant vegetation layer accounted for main position(73.72%-93.37%and 71.57%-85.24%).(2)The soil carbon and nitrogen storage(67.45-243.21 t/ha and 2.44-13.53 t/ha)decreased along the environmental gradient in a step-by-step manner(L>C>D≈LN>LX≈LT),there were three types of vertical spatial differentiation of carbon stock:first constant and then decreasing(L),first increasing and then decreasing(C,D and LN),and decreasing(LX and LT),and those of nitrogen storage were basically the same as that of carbon stock(only C and LX were slightly different).(3)The carbon and nitrogen storage(122.20-245.38 t/ha and 3.31-13.58 t/ha)of the ecosystem decreased first and then steadily or decreased in a step-by-step manner along the environmental gradient,respectively,the proportion of carbon and nitrogen in soil decreased(50.27%-99.11%and 73.48%-99.57%),but that of vegetation increased(0.89%-49.73%and 0.43%-26.52%).(4)The carbon storage of

关 键 词：生态系统 湖泊湿地 碳氮储量 环境梯度 空间分异规律 

分 类 号：S718.51[农业科学—林学] X143[环境科学与工程—环境科学]