鄱阳湖苔草湿地非淹水期CO_2释放特征  

Characteristics of CO_2 emission from Carex-dominated wetland in Poyang Lake in non-flooded period

作　　者：胡启武[1,2] 幸瑞新[1] 朱丽丽[1] 吴琴[1] 尧波[1] 刘影[1] 胡斌华 

机构地区：[1]江西师范大学地理与环境学院,南昌330022 [2]鄱阳湖湿地与流域研究教育部重点实验室,南昌330022 [3]鄱阳湖南矶湿地国家级自然保护区,南昌330127

出　　处：《应用生态学报》2011年第6期1431-1436,共6页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(40803022);江西省教育厅青年科学基金项目(GJJ10094)资助

摘　　要：2009年9月至2010年4月非淹水期,在鄱阳湖南矶湿地国家级自然保护区,选择以灰化苔草为建群种的洲滩湿地,设置土壤-植物系统（TC）、剪除植物地上部分（TJ）2个试验处理（分别代表生态系统和土壤呼吸）,利用密闭箱-气相色谱法测定了非淹水期鄱阳湖苔草湿地CO2释放通量.结果表明：苔草湿地生态系统呼吸与土壤呼吸均具有明显的季节变化模式,释放速率变化范围分别为89.57~1243.99和75.30~960.94 mg CO2.m-2.h-1,土壤呼吸占生态系统呼吸的比例为64%（39%~84%）;土壤温度是苔草湿地CO2通量的主要控制因子,可以解释呼吸速率80%以上的变异;生态系统呼吸与土壤呼吸的温度敏感性指数（Q10）分别为3.31和2.75,且冬季的Q10值明显高于春秋季节;土壤水分与CO2释放速率之间未达到显著相关;非淹水期,鄱阳湖苔草湿地是大气CO2的汇,其强度为1717.72 g C.m-2.By using static chamber/gas chromatography,the CO2 fluxes in a Carex cinerascen-dominated wetland in the Poyang Lake Nanji Wetland National Nature Reserve were measured in non-flooded period（from September 2009 to April 2010）.Two treatments were installed,i.e.,soil-plant system（TC） and aboveground plant removal（TJ）,representing ecosystem respiration and soil respiration,respectively.There was an obvious seasonal variation in the ecosystem respiration and soil respiration.The respiration rate in treatment TC ranged from 89.57 to 1243.99 mg CO2·m-2·h-1,and that in TJ was from 75.30 to 960.94 mg CO2·m-2·h-1.Soil respiration accounted for 39%-84% of ecosystem respiration,with an average of 64%.Soil temperature was the main factor controlling the ecosystem respiration and soil respiration,explaining more than 80% of the respiration variance.The temperature coefficient（Q10）,an index of temperature sensitivity for respiration,was 3.31 for ecosystem respiration and 2.75 for soil respiration.The Q10 value was higher in winter than in autumn and spring.No significant correlation was observed between soil moisture and CO2 fluxes.In non-flooded period,the C.cinerascens-dominated wetland acted as a carbon sink of atmospheric CO2,with a carbon uptake of 1717.72 g C·m-2.

关 键 词：鄱阳湖 湿地 生态系统呼吸 土壤呼吸 Q10 

分 类 号：Q149[生物学—生态学]