青海湖流域不同高寒湿地温室气体通量对降水变化的响应  

Response of greenhouse gas fluxes of different alpine wetlands in Qinghai Lake Basin to changes in precipitation

作　　者：蒋莉莉 陈克龙[1,2] 周华坤 谢宝华[4] 朱锦福 左弟召[2] JIANG Lili;CHEN Kelong;ZHOU Huakun;XIE Baohua;ZHU Jinfu;ZUO Dizhao(College of Life Science,Qinghai Normal University,Xining 810008,China;Qinghai Province Key Laboratory of Physical Geography and Environmental Process,Xining 810008,China;Northwest Institute of Plateau Biology,Chinese Academy of Sciences,Qinghai Province Key Laboratory of Restoration Ecology,Xining 810008,China;Yantai Coastal Zone Research Institute,Chinese Academy of Sciences,Yantai 264003,China)

机构地区：[1]青海师范大学生命科学学院,青海西宁810008 [2]青海省自然地理与环境过程重点实验室,青海西宁810008 [3]中国科学院西北高原生物研究所,青海省寒区恢复生态学重点实验室,青海西宁810008 [4]中国科学院烟台海岸带研究所,山东烟台264003

出　　处：《生态科学》2024年第6期31-42,共12页Ecological Science

基　　金：国家重点研发项目(2017YFC0403601);青海省科技厅项目(2018-ZJ-T09);青海省科技厅项目(2019-ZJ-7068)。

摘　　要：随着全球气候变化,降水量和降水强度的变化成为热点议题。以青海湖流域瓦颜山和鸟岛湿地为研究对象,设降水梯度为减雨50%(P_(-))、自然对照(P_(0))、增雨50%(P_(+)),采用静态箱—气相色谱法研究不同降水对两种湿地CO_(2)、CH_(4)、N_(2)O通量的影响,并分析其作用因子。结果表明:1)生长季两种湿地均为CO_(2)和N_(2)O排放源,其月均排放量瓦颜山为132.82 mg·m^(-2)·h^(-1)和0.38μg·m^(-2)·h^(-1),鸟岛为90.79 mg·m^(-2)·h^(-1)和0.79μg·m^(-2)·h^(-1),瓦颜山为CH_(4)的吸收汇,其吸收量为3.21μg·m^(-2)·h^(-1),鸟岛为CH_(4)的排放源,其排放量为1.84μg·m^(-2)·h^(-1);2)不同降水处理对两种湿地的CO_(2)和N_(2)O排放均无显著影响,对CH_(4)交换量影响显著(P<0.05),瓦颜山CH_(4)吸收量为:8月>9月>5>月6月>7月,P_(-)较P_(0)减少41.34%,P_(-)促进CH_(4)排放,P_(+)较P_(0)减少85.91%,P_(+)促进CH_(4)吸收,鸟岛生长季CH_(4)排放通量:9月>8月>7>月6月>5月,P_(-)较P_(0)减少57.40%,P_(+)较P_(0)增加72.51%。3)不同降水处理对两种湿地的生物量影响均不显著(P>0.05)且呈现一致的影响结果,增雨会增加地上、地下生物量,同时会减少凋落物含量,减雨处理反之。4)不同降水处理对两种湿地的土壤因子的影响均不显著(P>0.05),表现在:增雨会增加土壤湿度,较小尺度降低土壤温度,减雨处理反之;增减雨处理均会降低土壤的全氮、全碳含量;生长季两种湿地净氨化速率均为正值,即铵态氮含量在生长季节呈现增加的趋势,而净硝化速率为负值,则硝态氮含量呈减少趋势。5)高寒湿地温室气体交换的影响因子和交换机理因湿地类型而异。Along with the global climate change,precipitation and precipitation intensity have become hot topics.In this study,the wetland at the source of the Wayanshan in the Qinghai Lake Basin,the Bird Island Wetland between Buha Estuary Wetland and Lakeside Wetland were used as research objects from May to September 2019.The precipitation gradient was set to 50%rain reduction(P_(-)),natural control(P_(0)),50%rain increase(P_(+)),and static box-gas chromatography was used to study the CO_(2),CH_(4),and N_(2)O fluxes of two types of wetlands with different precipitation and their contributing factors.The results showed that:1)Both types of wetlands in the growing season were emission sources of CO_(2) and N_(2)O,the average monthly emission in Wayanshan was 132.82 mg·m^(-2)·h^(-1) and 0.38μg·m^(-2)·h^(-1),the Bird Island was 90.79 mg·m^(-2)·h^(-1) and 0.79μg·m^(-2)·h^(-1),the Wayanshan was an absorption sink for CH_(4),and its absorption was 3.21μg·m^(-2)·h^(-1).The Bird Island was the source of CH_(4) emissions with value of 1.84μg·m^(-2)·h^(-1).2)Different precipitation treatments had no significant impact on emission of CO_(2) and N_(2)O in the two wetlands,but significantly affected the amount of CH_(4) exchange(P<0.05).The amount of CH_(4) absorbed in Wayanshan was:August>September>May>June>July.P_(-)was 41.34%lower than that of P_(0),and Ppromoted emission of CH_(4).P_(+)was 85.91%lower than that of P_(0),and P_(+)promoted absorption of CH_(4).Emission flux of CH_(4) in the Bird Island during the growing season was as follows:September>August>July>June>May.P_(-)was 57.40%lower than that of P_(0),and P_(+)was 72.51%higher than that of P_(0).3)The effects of different precipitation treatments on the biomass of the two wetlands were not significant(P>0.05)and showed consistent results.Increased rain would increase aboveground and underground biomass.At the same time,it would reduce the litter content,and the rain reduction treatment was reversed.4)The effects of different precipitation treatments on the

关 键 词：青海湖 高寒湿地 模拟降水 温室气体 

分 类 号：S157.2[农业科学—土壤学]