Generality of Hydrologic Transport Limitation of Watershed Organic Carbon Flux Across Ecoregions of the United States
Generality of Hydrologic Transport Limitation of Watershed Organic Carbon Flux Across Ecoregions of the United States
复制标题
DOI：
10.1029/2018gl080005
复制
发表时间：
2018-11
影响因子：
5.2
通讯作者：
J. Zarnetske;M. Bouda;Benjamin W. Abbott;J. Saiers;P. Raymond
中科院分区：
文献类型：
--
作者：
J. Zarnetske;M. Bouda;Benjamin W. Abbott;J. Saiers;P. Raymond
尽管通过淡水的溶解有机碳（DOC）通量几乎相当于所有陆地生态系统的净碳吸收量，但源过程（碳生产和位置）和运输过程（水文连通性和路线）如何相互作用以确定跨流动条件和生态区的 DOC 通量仍然存在不确定性。这限制了我们预测河流碳通量对气候和土地利用变化的响应的能力。我们使用 DOC 浓度和排放模式以及集合建模技术来量化跨越不同气候和土地覆盖条件的 1,006 个美国流域的 DOC 通量行为。我们发现 80% 的流域中 DOC 通量受到运输限制（浓度随排放量增加），并且这种通量行为跨越生态区和流域大小。传输限制的普遍性表明，如何将排放模型与广泛可用的流域特性相结合，可以使 DOC 通量有效地集成到景观和地球系统模型中。
Although the flux of dissolved organic carbon (DOC) through freshwaters is nearly equivalent to the net carbon uptake of all terrestrial ecosystems, uncertainty remains about how source processes (carbon production and location) and transport processes (hydrologic connectivity and routing) interact to determine DOC flux across flow conditions and ecoregions. This limits our ability to predict the fluvial carbon flux responses to changes in climate and land use. We used DOC concentration and discharge patterns with ensemble modeling techniques to quantify DOC flux behavior for 1,006 U.S. watersheds spanning diverse climate and land cover conditions. We found that DOC flux was transport‐limited (concentration increased with discharge) in 80% of watersheds and that this flux behavior spanned ecoregions and watershed sizes. The generality of transport limitation demonstrates how coupling discharge models with widely available watershed properties could allow DOC flux to be efficiently integrated into landscape and Earth system models.