摘要
溶解碳随森林溪流水体流动的过程是生态系统碳源汇过程的重要内容。为了解溪流水体溶解碳输出的潜在能力,以青藏高原东缘典型高山森林为研究对象,于2015年7月溪流径流量最大的降雨季节,在集水区4.31 km^2的范围内,调查所有15条溪流水体中溶解碳的输出特征。结果表明,单位集水区面积溶解碳的最大年输出速率为12.99×103kg·km^(-2)。高山森林溪流水体中全碳、无机碳和有机碳的单位集水区面积的输出速率分别为3.56×10^(-2)、2.12×10^(-2)和1.43×10^(-2)g·m^(-2)·d^(-1);全碳、无机碳和有机碳的单位溪流面积的输出速率分别为2.01×103、1.20×103和0.81×103kg·m^(-2)·d^(-1)。长度大于30 m的溪流,全碳和无机碳的浓度表现为源头>入河口,而有机碳的浓度则相反;长度小于30 m的溪流,全碳、无机碳和有机碳的浓度均表现为入河口>源头。这些结果表明,降雨季节高山森林生态系统溪流水体流动导致大量溶解碳的流失。本研究为深入认识气候变化情景下高山森林陆地系统与水体间的生态联系提供了新思路。
Dissolved carbon flow from water in the alpine forest headwater streams is one of the essential components of carbon flux. A study on dissolved carbon output with water flow in the alpine headwater streams was carried out in a typical alpine forest in the eastern Qinghai-Tibet Plateau in July 2015. The output characteristics of dissolved carbon with water flow were investigated in the catchment covering an area of 4.31 km2. The results are given as follows. The maximum annual output rate of dissolved carbon in unit area catchment was 12. 99 ·103 kg.km-2. The output rates of the unit area of catchment were 3.56 × 10-2 g,m-2 .d-1 for total carbon, 2. 12 × 10-2 gom-2 .d-1 for inorganic carbon, and 1.43 × 10-2 g.m-2 .d-1 for organic carbon in the alpine forest headwater streams. In contrast, the output rates of the unit area of stream were 2.01 × 10^3 kg. m-2 ·d-1 for total carbon, 1.20×10^3 kg.m-2 .d-1 or inorganic carbon, and 0. 81 ×10^3 kg-m-2 .d-1 for organic carbon. For streams with length greater than 30 m, total carbon and inorganic carbon concentrations were higher in stream source than at stream end, but organic carbon concentration showed the opposite. Contrarily, for streams with length less than 30 m, the concentrations of total carbon, inorganic carbon, and organic carbon had larger values at stream end than in stream source. These results suggest that the water flow in the alpine forest headwater streams leads to a large amount loss of dissolved carbon. This study provides a new idea for further studies on the ecological linkage between the land system and water body under the climate change.
作者
张钰
杨万勤
谭波
梁子逸
吴福忠
ZHANG Yu YANG Wanqin TAN Bo LIANG Ziyi WU Fuzhong(Sichnan Province Key Laboratory of Ecological Forestry Engineering, Institute of Forestry ＆ Ecology, Siehuan Agricultural University, Chengdu 611130, China Research Station of Alpine Forest Ecosystem, Institute of Forestry ＆ Ecology, Sichuan Agricultural University, Chengdu 611130, China)
出处
《中国科学院大学学报（中英文）》
CSCD
北大核心
2017年第4期515-520,共6页
Journal of University of Chinese Academy of Sciences
基金
国家自然科学基金(31270498
31570445
31500358)
高等学校博士学科点专项(20135103110002)资助
关键词
高山森林溪流
溶解碳流失
集水区
碳源汇
forest headwater streams
dissolved carbon loss
catchment
carbon source and sink
