Limnology/Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden.
Estonian Marine Institute, University of Tartu, Tallinn, Estonia.
Sci Rep. 2020 May 21;10(1):8471. doi: 10.1038/s41598-020-65010-3.
The pool of dissolved organic carbon (DOC), is one of the main regulators of the ecology and biogeochemistry of inland water ecosystems, and an important loss term in the carbon budgets of land ecosystems. We used a novel machine learning technique and global databases to test if and how different environmental factors contribute to the variability of in situ DOC concentrations in lakes. In order to estimate DOC in lakes globally we predicted DOC in each lake with a surface area larger than 0.1 km. Catchment properties and meteorological and hydrological features explained most of the variability of the lake DOC concentration, whereas lake morphometry played only a marginal role. The predicted average of the global DOC concentration in lake water was 3.88 mg L. The global predicted pool of DOC in lake water was 729 Tg from which 421 Tg was the share of the Caspian Sea. The results provide global-scale evidence for ecological, climate and carbon cycle models of lake ecosystems and related future prognoses.
溶解有机碳（DOC）库是内陆水生态系统生态和生物地球化学的主要调节因子之一，也是陆地生态系统碳预算中的一个重要损失项。我们使用一种新颖的机器学习技术和全球数据库，测试了不同环境因素是否以及如何影响湖泊中原位 DOC 浓度的变异性。为了估算全球湖泊中的 DOC，我们对每个面积大于 0.1km²的湖泊进行了 DOC 预测。流域特性以及气象和水文特征解释了湖泊 DOC 浓度变化的大部分原因，而湖泊形态学仅起次要作用。预测的全球湖泊水中平均 DOC 浓度为 3.88mg/L。全球湖泊水中预测的 DOC 库为 729Tg，其中里海占 421Tg。研究结果为湖泊生态系统的生态、气候和碳循环模型以及相关的未来预测提供了全球尺度的证据。
