Center for Ecological Research, Northeast Forestry University, Harbin 150040, China.
Jilin Province Baihe Forestry Bureau, Yanbian 133613, Jilin, China.
Ying Yong Sheng Tai Xue Bao. 2023 Sep;34(9):2363-2373. doi: 10.13287/j.1001-9332.202309.006.
Lacustrine wetlands have long-term carbon storage capacity and contribute significantly to regional carbon cycle, but it is unclear how its carbon sinks respond to climate change. We measured soil heterotrophic respiration carbon emissions (CO and CH), vegetation carbon sequestration, and related environmental factors (temperature, water level, .) of five kinds of natural swamps ( marsh-L, marsh-C, swamp-D, swamp-H, swamp-LT)by using static chamber gas chromatography and relative growth equation methods, along the water environmental gradients from lakeside to highlands in Yuanchi of Changbai Mountains. We quantified the carbon source/sink function (CSS) and global warming potential (GWP) of various swamp types by estimating ecosystem net carbon balance, and revealed the variation patterns and formation mechanisms of CSS and GWP along the environmental gradients, aiming to explore the response of carbon source/sink of lakeside wetland in high altitude area to climate change. The results showed that marshes (L and C) were weak sources (-1.018 and -0.090 t C·hm·a) at the lower habitats of the water environment gradient, shrub swamps (D and H) were strong or weak sinks (1.956 and 0.239 t C·hm·a) at the middle habitats, forest swamp (LT) was strong source (-3.214 t C·hm·a) at the upper habitat. The spatial changes were promoted by water level and suppressed by soil temperature. For GWP, strong thermal radiation for marshes (from 44.682 to 59.282 t CO·hm·a), cold radiation for shrub swamps (from -0.920 to -7.008 t CO·hm·a), and weak thermal radiation for forest swamp (11.668 t CO·hm·a), and their GWP was only promoted by soil temperature. Under current climate change background, marshes and forest swamp at both ends of the water environment gradient from lakeside to highlands played a positive feedback effect due to the increases of CH or CO emissions, while the middle shrub swamp still maintained a negative feedback effect in Yuanchi located the high-altitude area of the temperate Changbai Mountains.
湖泊湿地具有长期的碳储存能力，对区域碳循环有重要贡献，但湿地碳汇对气候变化的响应机制尚不清楚。本研究沿长白山天池湖滨到高山的水环境梯度，采用静态箱-气相色谱法和相对生长方程法，对 5 种自然沼泽（沼泽 L、沼泽 C、沼泽 D、沼泽 H、林下水生沼泽 LT）的土壤异养呼吸碳排放量（CO 和 CH）、植被碳固存及其相关环境因子（温度、水位、……）进行了测定。通过估算生态系统净碳平衡，量化了不同沼泽类型的碳源/汇功能（CSS）和全球变暖潜势（GWP），揭示了 CSS 和 GWP 沿环境梯度的变化规律和形成机制，旨在探讨高寒山区湖滨湿地碳源/汇对气候变化的响应。结果表明，在水环境梯度的低海拔生境中，沼泽（L 和 C）为弱碳源（-1.018 和-0.090 t C·hm·a），灌木沼泽（D 和 H）为中强或弱碳汇（1.956 和 0.239 t C·hm·a），森林沼泽（LT）为强碳源（-3.214 t C·hm·a）。空间变化受水位促进，受土壤温度抑制。就 GWP 而言，对沼泽（44.682 到 59.282 t CO·hm·a）有强热辐射，对灌木沼泽（-0.920 到-7.008 t CO·hm·a）有冷辐射，对森林沼泽（11.668 t CO·hm·a）有弱热辐射，GWP 仅受土壤温度的促进。在当前气候变化背景下，长白山天池湖滨到高山的水环境梯度两端的沼泽和森林沼泽由于 CH 或 CO 排放量的增加而产生正反馈效应，而处于中海拔的中间灌木沼泽仍保持负反馈效应。
