Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, PR China.
Jiangsu Environmental Engineering and Technology Co., Ltd., Jiangsu Environmental Protection Group Co., Ltd., Nanjing, 210036, China.
Environ Pollut. 2022 Jan 1;292(Pt A):118276. doi: 10.1016/j.envpol.2021.118276. Epub 2021 Oct 1.
Limnologists and governments have long had an interest in whether nitrogen (N) and/or phosphorous (P) limit algal productivity in lakes. However, the types and importance of anthropogenic and biogeochemical processes of N and P differ with lake trophic status. Here, a global lake dataset (annual average data from 831 lakes) demonstrates that total nitrogen (TN): total phosphorous (TP) ratios declined significantly as lakes become more eutrophic. From oligotrophic to hypereutrophic lakes, the probability of N and P co-limitation significantly increases from 15.0 to 67.0%, while P-only limitation decreases from 77.0 to 22.3%. Furthermore, TN:TP ratios are mainly affected by concentrations of TP (r = -0.699) rather than TN (r = -0.147). These results reveal that lake eutrophication mainly occurs with increasing P rather than N, which shifts lake ecosystems from stoichiometric P limitation toward a higher probability of N and P co-limitation. This study suggests that low N:P stoichiometry and a high probability of N and P co-limitation tend to occur in eutrophic systems.
长期以来，湖沼学家和政府一直关注氮（N）和/或磷（P）是否限制湖泊中藻类的生产力。然而，N 和 P 的人为和生物地球化学过程的类型和重要性因湖泊营养状态而异。在这里，一个全球湖泊数据集（来自 831 个湖泊的年平均数据）表明，随着湖泊富营养化程度的增加，总氮（TN）与总磷（TP）的比值显著下降。从贫营养到富营养湖泊，N 和 P 共同限制的可能性从 15.0%显著增加到 67.0%，而 P 限制的可能性从 77.0%下降到 22.3%。此外，TN:TP 比值主要受 TP 浓度的影响（r = -0.699），而不是 TN（r = -0.147）。这些结果表明，湖泊富营养化主要是由于 P 的增加而不是 N 的增加，这使得湖泊生态系统从化学计量 P 限制转向更高的 N 和 P 共同限制的可能性。本研究表明，低 N:P 化学计量和高 N 和 P 共同限制的可能性往往出现在富营养化系统中。
