Integrating Aquatic Metabolism and Net Ecosystem CO2 Balance in Short- and Long-Hydroperiod Subtropical Freshwater Wetlands
Integrating Aquatic Metabolism and Net Ecosystem CO2 Balance in Short- and Long-Hydroperiod Subtropical Freshwater Wetlands
复制标题
DOI：
10.1007/s10021-021-00672-2
复制
发表时间：
2021-07
期刊：
影响因子：
3.7
通讯作者：
S. Malone;Junbin Zhao;J. Kominoski;G. Starr;C. Staudhammer;P. Olivas;Justin C. Cummings;S. Oberbauer
中科院分区：
文献类型：
--
作者：
S. Malone;Junbin Zhao;J. Kominoski;G. Starr;C. Staudhammer;P. Olivas;Justin C. Cummings;S. Oberbauer
水生初级生产力如何影响湿地固碳能力尚不确定。我们评估了水生碳动态的幅度和变化，并将其与大沼泽地国家公园石灰质淡水湿地内的净生态系统CO2交换（NEE）和生态系统呼吸（Reco）速率进行了比较。我们连续记录30分钟的溶解氧（DO），水位，水温（Twater），光合有效辐射（PAR）的测量。这些测量结果与5年（2012-2016年）的生态系统CO2通量相结合，分别在长水文周期的富含泥炭的淡水沼泽和短水文周期的淡水泥灰岩草原中进行。每日净水生初级生产力（NAPP）率表明，这两个湿地一般净异养。水生初级生产力（GAPP）为0至− 6.3 g C m−2day− 1，水生呼吸（RAq）为0至6.13 g C m−2day−1。水位、Twater、GAPP和RAq之间的非线性相互作用导致NAPP的高度变异性，从而导致NEE。净水生初级生产力占4-5%的偏差解释NEE率。关于通量大小，每日NAPP是一个更大的比例，每日NEE在长水文周期的网站（平均值= 95%）相比，短水文周期的网站（平均值= 64%）。虽然我们已经证实了NAPP NEE在长和短水文周期淡水湿地的显着贡献，水生和生态系统通量的脱钩可能在很大程度上取决于新兴植被，碳酸盐循环，和横向C通量。
How aquatic primary productivity influences the carbon (C) sequestering capacity of wetlands is uncertain. We evaluated the magnitude and variability in aquatic C dynamics and compared them to net ecosystem CO2exchange (NEE) and ecosystem respiration (Reco) rates within calcareous freshwater wetlands in Everglades National Park. We continuously recorded 30-min measurements of dissolved oxygen (DO), water level, water temperature (Twater), and photosynthetically active radiation (PAR). These measurements were coupled with ecosystem CO2fluxes over 5 years (2012–2016) in a long-hydroperiod peat-rich, freshwater marsh and a short-hydroperiod, freshwater marl prairie. Daily net aquatic primary productivity (NAPP) rates indicated both wetlands were generally net heterotrophic. Gross aquatic primary productivity (GAPP) ranged from 0 to − 6.3 g C m−2day−1and aquatic respiration (RAq) from 0 to 6.13 g C m−2day−1. Nonlinear interactions between water level,Twater, and GAPP andRAqresulted in high variability in NAPP that contributed to NEE. Net aquatic primary productivity accounted for 4–5% of the deviance explained in NEE rates. With respect to the flux magnitude, daily NAPP was a greater proportion of daily NEE at the long-hydroperiod site (mean = 95%) compared to the short-hydroperiod site (mean = 64%). Although we have confirmed the significant contribution of NAPP to NEE in both long- and short-hydroperiod freshwater wetlands, the decoupling of the aquatic and ecosystem fluxes could largely depend on emergent vegetation, the carbonate cycle, and the lateral C flux.