水分变化对若尔盖高寒湿地木里薹草（Carex muliensis）枯落物分解及CO2排放的影响  

Effects of Water Change on Decomposition and CO2 Emission of Litter of Carex muliensis in Zoige Alpine Wetland

作　　者：丁艳[1] 张晓雅[1] 高俊琴[1] 李谦维 乐艺 蒋丽华 DING Yan;ZHANG Xiao-ya;GAO Jun-qin;LI Qian-wei;YUE Yi;JIANG Li-hua(School of Nature Conservation,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学自然保护区学院

出　　处：《生态与农村环境学报》2019年第8期1027-1033,共7页Journal of Ecology and Rural Environment

基　　金：国家自然科学基金(41571084,41871077)

摘　　要：枯落物分解是湿地生态系统物质循环和能量流动的重要环节,是调控全球碳平衡的关键过程之一。深入探究枯落物分解对水分变化的响应,对于了解湿地生态系统碳动态及其对气候变化的反馈至关重要。以若尔盖高寒湿地优势植物种木里薹草(Carex muliensis)枯落物为研究对象,设置不同水量和频率的干湿交替变化试验,测定枯落物失重率以及CO2排放量,研究枯落物分解对于水分变化的响应。结果表明,培养期间水分变化对木里薹草枯落物失重率没有显著影响。不同干湿交替处理下枯落物失重率的变化范围为31.64%~34.26%。水量、频率及两者交互作用对枯落物CO2排放均有显著影响(P<0.05)。与低水量相比,高水量处理增加了木里薹草枯落物CO2排放量。在高水量处理下,降低降水频率可显著增加CO2排放(P<0.05),高、低频率下CO2排放量分别为(5.28±0.24)和(10.77±0.64)g·kg^-1。因此,未来降水格局变化(包括降水量和降水频率变化)将对若尔盖高寒湿地木里薹草枯落物分解过程中的CO2排放产生重要影响。Litter decomposition is an important part of material circulation and energy flowing in wetland ecosystem and one of the key processes to regulate global carbon balance. The litters of Carex muliensis in Zoige alpine wetland were collected, and the weightlessness rate and the CO2 emission with different water volumes and watering frequencies were measured to explore the response of litter decomposition to water change. The results show that there was no significant effect of water change on the litter weightlessness rate. The litter weightlessness rate under different drying-rewetting cycle was between 31.64%-34.26%. The water volumes, watering frequency and their interaction significantly affected the CO2 emission during the litter decomposition (P<0.05). The CO2 cumulative emission was higher under the high water volumes than the low water volumes treatment. Under the high water volumes, the decrease of watering frequency significantly promoted the CO2 cumulative emission(P<0.05). The CO2 emission was (5.28±0.24) and (10.77±0.64) g·kg^-1 under the high and the low watering frequency treatment, respectively. Therefore, changes of precipitation patterns in future, including altered precipitation volumes and frequency, will have an important impact on the litter decomposition and the CO2 emission of Zoige alpine wetland.

关 键 词：干湿交替 木里薹草 枯落物分解 CO2排放 若尔盖湿地 

分 类 号：X82[环境科学与工程—环境工程] Q948.1[生物学—植物学]