Landscape geomorphic characteristic impacts on greenhouse gas fluxes in exposed stream and riparian sediments.
Landscape geomorphic characteristic impacts on greenhouse gas fluxes in exposed stream and riparian sediments.
复制标题
景观地貌特征对裸露河流和河岸沉积物中温室气体通量的影响。
DOI：
--
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
S. Serchan
中科院分区：
文献类型：
--
作者：
P. Vidon;S. Serchan
虽然由于燃烧化石燃料而向大气中过量排放温室气体（GHG：N2O、CO2、CH4）仍然令人担忧，但我们还需要更好地量化自然系统的温室气体排放。本研究调查了从源头河段到低地湿地河段的一系列地貌位置的 7 个河段（河岸带 + 暴露的河床沉积物）土壤-大气界面的温室气体通量。当夏季基流条件下将河岸通量 (RZ) 与河内位置 (IS) 的通量进行比较时，RZ 位置的总二氧化碳当量 (CO2eq) 排放量大约比 IS 位置高 5 倍，其中大多数 CO2eq 是由潮湿条件占主导地位的 RZ 位置（源头湿地、低地湿地）的 CH4 生产驱动的。在逐个气体的基础上，无论位置如何（水源与低地河段），RZ 和 IS 位置之间的 N2O 通量没有观察到明显差异，而 RZ 位置的 CO2 通量明显大于 IS 位置。 RZ 和 IS 地点受湿地影响的河段的甲烷通量明显高于其他河段。然而，GHG 通量与 DOC、DO、NO3(-)、NH4(+) 或水温并不一致，这凸显了使用水质参数来预测洪泛区规模的 GHG 排放的局限性，至少在夏季基流条件下是这样。随着制定进一步限制整个流域温室气体排放的策略，我们提出将景观地貌特征与土壤-大气界面的温室气体通量联系起来的方法为成功预测流域尺度洪泛区的温室气体排放提供了一条有前途的途径。
While excessive releases of greenhouse gases (GHG: N2O, CO2, CH4) to the atmosphere due to the burning of fossil fuel remains a concern, we also need to better quantify GHG emissions from natural systems. This study investigates GHG fluxes at the soil-atmosphere interface in a series of 7 stream reaches (riparian zones + exposed streambed sediment) across a range of geomorphic locations from headwaters reaches to lowland wetland reaches. When riparian fluxes (RZ) are compared to fluxes from in-stream locations (IS) under summer baseflow conditions, total CO2-equivalent (CO2eq) emissions are approximately 5 times higher at RZ locations than at IS locations, with most CO2eq driven by CH4 production at RZ locations where wet conditions dominate (headwater wetlands, lowland wetlands). On a gas-by-gas basis, no clear differences in N2O fluxes between RZ and IS locations were observed regardless of locations (headwater vs. lowland reaches), while CO2 fluxes were significantly larger at RZ locations than IS locations. Methane fluxes were significantly higher in wetland-influenced reaches than other reaches for both RZ and IS locations. However, GHG fluxes were not consistently correlated to DOC, DO, NO3(-), NH4(+), or water temperature, stressing the limitations of using water quality parameters to predict GHG emissions at the floodplain scale, at least during summer baseflow conditions. As strategies are developed to further constrain GHG emission for whole watersheds, we propose that approaches linking landscape geomorphic characteristics to GHG fluxes at the soil-atmosphere interface offer a promising avenue to successfully predict GHG emissions in floodplains at the watershed scale.
影响因子：
11.6
作者：
M. Turetsky;A. Kotowska;J. Bubier;N. Dise;P. Crill;E. Hornibrook;K. Minkkinen;T. Moore;I. Myers-Smith
通讯作者：
M. Turetsky;A. Kotowska;J. Bubier;N. Dise;P. Crill;E. Hornibrook;K. Minkkinen;T. Moore;I. Myers-Smith