文献类型：期刊文献

中文题名：不同退化程度高寒草甸生态系统碳通量

英文题名：Dynamics of carbon flux of alpine meadows along a degradation gradient

作者：徐干君[1] 柴永煜[1] 颜亮[2,3] 吴胜义[1] 李勇[2,3] 康恩泽[2,3] 汪晓东[2,3] 杨澳[2,3] 康晓明[2,3] 张骁栋[2,3]

第一作者：徐干君

机构：[1]国家林业和草原局西北调查规划院,陕西西安710048;[2]湿地生态功能与恢复北京市重点实验室/中国林业科学研究院生态保护与修复研究所,北京100091;[3]四川若尔盖高寒湿地生态系统定位观测研究站,四川阿坝624500

年份：2022

卷号：39

期号：9

起止页码：1733-1742

中文期刊名：草业科学

外文期刊名：Pratacultural Science

收录：CSTPCD;;北大核心:【北大核心2020】；CSCD:【CSCD2021_2022】；

基金：国家林业和草原局西北调查规划院科技创新项目(GLXD-2021-QT-20);国家自然科学基金(31770511)。

语种：中文

中文关键词：草地退化;生态系统净交换;生态系统呼吸;总生态系统生产力;二氧化碳通量;甲烷通量;青藏高原

外文关键词：grassland degradation;net ecosystem exchange;ecosystem respiration;gross ecosystem productivity;CO2 flux;CH4 flux;Qinghai-Tibet Plateau

分类号：S812

摘要：高寒草甸是青藏高原的主要植被类型之一。受气候变化和人类活动的影响,高寒草甸面临不同程度的退化,生态系统碳通量也随之改变。当前,高寒草甸退化过程中的碳通量组分变化特征仍不明晰,对于深入理解高寒草甸碳源汇格局对全球变化的响应产生阻碍。本研究以4个退化梯度(对照样地、轻度退化、中度退化和重度退化)的高寒草甸为研究对象,利用静态箱法测定了夏季不同退化程度的高寒草甸生态系统净交换(NEE)、生态系统呼吸(ER)、总生态系统生产力(GEP)和甲烷(CH)通量以及相关环境因子。结果表明:1)夏季不同退化程度的高寒草甸为显著的CO汇,NEE范围为-1 437.55~-98.45 mg·(m^(2)·h)(CO),NEE、ER和GEP随着高寒草甸退化而显著减弱(P <0.05);同时高寒草甸呈微弱的CH汇,平均吸收速率为0.029 mg·(m^(2)·h)(CH),CH通量随退化加剧无显著变化(P>0.05)。2)土壤有机碳含量和植被盖度是影响NEE、GEP和ER的主要环境因素。本研究发现高寒草甸碳汇从轻度退化到中度退化急剧减弱了约55%,说明加强预防高寒草甸从轻度到中度退化的演替,将有效维持高寒草甸的碳汇功能。
Alpine meadow is one of the main vegetation types in the Qinghai-Tibet Plateau. Alpine meadows are variably degraded under the influence of climate change and human activities. The carbon flux in alpine meadows changes with the degradation. However, the characteristics of carbon flux components during degradation in alpine meadows are still unclear,hindering our understanding of the transition between carbon sink and source in responding to global changes. In this study,four degradation degrees of alpine meadows, including enclosure as control check, lightly degraded, moderately degraded,and severely degraded meadows were studied. The net ecosystem exchange(NEE), ecosystem respiration(ER), gross ecosystem productivity(GEP), methane(CH) fluxes, and related environmental factors were measured during the growing season by the static chamber method. Results showed that: 1) Alpine meadows with different degrees of degradation in summer were significant COsinks, with NEE ranging from-1 437.55 to-98.45 mg·(m^(2)·h)(CO);NEE, ER, and GEP decreased significantly with the degradation of alpine meado(CH)w(P < 0.05). The alpine meadow presented a weak CHsink with a mean rate of 0.029 mg·(m^(2)·h)(CH), showing no significant difference among degradation degrees(P > 0.05).2) Soil organic carbon content and vegetation coverage were the two main environmental factors that affected NEE, GEP,and ER. Our study found that the capacity of carbon sequestration of alpine meadows decreased by 55% from lightly degraded to moderately degraded in the growing season, indicating that more attention should be paid to the succession of alpine meadows from light to moderate degradation, which is crucial to maintaining the carbon sequestration function of alpine meadow.