Department of Geography, McGill University, Montreal, QC H3A 0B9, Canada; Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331, USA.
School of Physical and Geographical Sciences, Keele University, Staffordshire ST5 5BG, UK.
Sci Total Environ. 2015 Apr 1;511:381-92. doi: 10.1016/j.scitotenv.2014.12.065. Epub 2014 Dec 30.
The inundation of boreal forests and peatlands through the construction of hydroelectric reservoirs can increase carbon dioxide (CO2) and methane (CH4) emission. To establish controls on emission rates, we incubated samples of forest and peat soils, spruce litter, forest litter and peatland litter collected from boreal ecosystems in northern Quebec for 16 weeks and measured CO2 and CH4 production rates under flooded or non-flooded conditions and varying oxygen concentration and temperature. CO2 production under flooded conditions was less than under non-flooded conditions (5-71 vs. 5-85 mg Cg(-1) C), but CH4 production under flooded conditions was larger than under non-flooded conditions (1-8158 vs. 0-86 μg Cg(-1) C). The average CO2 and CH4 production rate factor for flooded:non-flooded conditions was 0.76 and 1.32, respectively. Under flooded conditions, high oxygen concentrations increased CO2 production in peat soils but decreased CH4 production in forest and peat soils and spruce litter. Warmer temperatures (from 4 to 22°C) raised both CO2 production in peat soils and peatland litter, and CH4 production in peat soils and spruce litter. This study shows that the direction and/or strength of CO2 and CH4 fluxes change once boreal forests and peatlands are inundated.
水力发电水库的建设会导致北方森林和泥炭地被淹没，从而增加二氧化碳（CO2）和甲烷（CH4）的排放。为了控制排放速率，我们对从魁北克北部北方森林和泥炭地生态系统收集的森林和泥炭土壤、云杉凋落物、森林凋落物和泥炭地凋落物样本进行了 16 周的培养实验，在水淹和非水淹条件下以及不同氧气浓度和温度下测量了 CO2 和 CH4 的产生速率。水淹条件下的 CO2 产生量小于非水淹条件下的 CO2 产生量（5-71 与 5-85mg Cg(-1) C），但水淹条件下的 CH4 产生量大于非水淹条件下的 CH4 产生量（1-8158 与 0-86μg Cg(-1) C）。水淹：非水淹条件下的 CO2 和 CH4 产生率因子分别为 0.76 和 1.32。在水淹条件下，高氧浓度增加了泥炭土中的 CO2 产生量，但减少了森林和泥炭土以及云杉凋落物中的 CH4 产生量。较高的温度（4-22°C）提高了泥炭土和泥炭地凋落物中的 CO2 产生量，以及泥炭土和云杉凋落物中的 CH4 产生量。本研究表明，一旦北方森林和泥炭地被淹没，CO2 和 CH4 通量的方向和/或强度就会发生变化。
