Multi-scale temporal variation in methane emission from an alpine peatland on the Eastern Qinghai-Tibetan Plateau and associated environmental controls
Multi-scale temporal variation in methane emission from an alpine peatland on the Eastern Qinghai-Tibetan Plateau and associated environmental controls
复制标题
青藏高原东部高山泥炭地甲烷排放的多尺度时间变化及相关环境控制
DOI：
10.1016/j.agrformet.2019.107616
复制
发表时间：
2019-10
影响因子：
6.2
通讯作者：
Linggui Yuan
中科院分区：
文献类型：
--
作者：
Haijun Peng;Qain Guo;Hanwei Ding;Bing Hong;Yongxuan Zhu;Yetang Hong;Cheng Cai;Yu Wang;Linggui Yuan
以往大多数关于泥炭地甲烷（CH 4）排放的研究都集中在北方、亚北极和热带地区。青藏高原东部高寒泥炭地广泛分布，对气候变化和人为干扰敏感，其CH 4排放量研究较少。为了研究该地区CH 4通量的日变化和季节变化，并识别影响CH 4通量的环境因子，在红原泥炭地建立了一个配有LI-7700开路式CH 4分析仪的涡度相关（EC）塔。2014年全年CH 4排放总量为46.8 g CH 4 m-2，其中非生长季排放量占全年排放总量的25%。2014年5月至9月，CH 4排放量日变化较大，通量变化范围为0.15 - 0.25 μmol m-2s-1。相比之下，在2014年的所有其他时期，没有观察到日变化，CH 4通量变化小于0.05 μmol m-2s-1。在土壤解冻和冻结季节，CH 4交换有明显的季节变化，CH 4排放量出现小的波动。利用小波分析方法对连续的CH 4通量时间序列进行分析，探讨了生长季生态系统CH 4交换的时间变化规律。在日尺度上，CH 4通量的变化与气温变化同步，并受摩擦速度和水汽压差（VPD）的影响。在周到月的时间尺度上，土壤温度可以解释CH 4交换的大部分变化。CH 4排放通量与地下水位无明显相关性，但与整个生长季接近地下水位的-25 cm土壤温度显著相关（R2= 0.86），表明地下水位和土壤温度对CH 4排放具有协同效应。这项研究强调了需要连续涡度相关测量和时间序列分析方法，以充分描述生态系统CH 4交换的时间变化。
Most previous studies on methane (CH4) emissions from peatlands have focused on the boreal, subarctic, and tropical regions. Little is known about CH4emissions from the alpine peatlands that are widely distributed in the eastern Qinghai-Tibetan Plateau (QTP), which are sensitive to climate change and human disturbance. To assess the magnitudes of daily and seasonal variations in CH4flux in this area, and to identify the influential environmental factors, an eddy covariance (EC) tower with a LI-7700 open-path CH4analyzer was established on Hongyuan Peatland. Total annual CH4emission was 46.8 g CH4m-2in 2014, with emissions in the non-growing season accounting for 25% of the annual total. From May to September 2014, diurnal variation in CH4emissions was observed, with CH4fluxes varying between 0.15 and 0.25 μmol m-2s-1. In contrast, during all other periods of 2014, no diurnal variation was observed, and CH4flux varied below 0.05 μmol m-2s-1. A clear seasonal pattern in CH4exchange with small surges in CH4emission appeared in soil thawing and freezing seasons. Wavelet analysis was applied to the continuous CH4flux time series to explore temporal variation in ecosystem CH4exchange during the growing season. On daily timescales, changes in CH4flux are in phase with changes in air temperature, and influenced by friction velocity and vapor pressure deficit (VPD). On weekly-to-monthly timescales, soil temperature can explain most of the variation in CH4exchange. Though CH4fluxes had no apparent correlation with water table level, fluxes were significantly (R2= 0.86) correlated with soil temperature measured at -25 cm depth, close to the water table level throughout the growing season, suggesting a synergistic effect of water table level and soil temperature on methane emission. This study highlights the need for continuous eddy covariance measurements and time series analysis approaches to adequately describe temporal variability in ecosystem CH4exchange.
登录
查看更多内容
影响因子：
9.4
作者：
Vargas, Rodrigo;Allen, Michael F.
通讯作者：
Allen, Michael F.
影响因子：
6.2
作者：
K. Tseng;Jeng-Lin Tsai;A. Alagesan;B. Tsuang;M. Yao;Pei-Hsuan Kuo
通讯作者：
K. Tseng;Jeng-Lin Tsai;A. Alagesan;B. Tsuang;M. Yao;Pei-Hsuan Kuo
中国东北连续多年冻土带北方泥炭地生长季甲烷排放：活动层深度和植被的影响
影响因子：
4.9
作者：
Y. Miao;C. Song;L. Sun;X. Wang;H. Meng;R. Mao
通讯作者：
R. Mao
影响因子：
4.4
作者：
FUNG, I;JOHN, J;FRASER, PJ
通讯作者：
FRASER, PJ
影响因子：
6.2
作者：
Detto, Matteo;Verfaillie, Joseph;Baldocchi, Dennis
通讯作者：
Baldocchi, Dennis