Dataset for: Phosphorus accumulates faster than nitrogen globally in freshwater ecosystems under anthropogenic impacts

Combined effects of cumulative nutrient inputs and biogeochemical processes that occur in freshwater under anthropogenic eutrophication could lead to myriad shifts in nitrogen (N):phosphorus (P) stoichiometry in global freshwater ecosystems, but this is not yet well-assessed. Here we evaluated the characteristics of N and P stoichiometries in bodies of freshwater and their herbaceous macrophytes across human-impact levels, regions and periods. Freshwater and its macrophytes had higher N and P concentrations and lower N:P ratios in heavily than lightly human-impacted environments, further evidenced by spatiotemporal comparisons across eutrophication gradients. N and P concentrations in freshwater ecosystems were positively correlated and N:P was negatively correlated with population density in China. These results indicate a faster accumulation of P than N in human-impacted freshwater ecosystems, which could have large effects on the trophic webs and biogeochemical cycles of estuaries and coastal areas by freshwater loadings, and reinforce the importance of rehabilitating these ecosystems.

人为富营养化（anthropogenic eutrophication）作用下，淡水生态系统中累积性营养盐输入与生物地球化学过程（biogeochemical processes）的联合效应，可引发全球淡水生态系统内氮（N）磷（P）化学计量比（stoichiometry）的诸多变化，但目前对此尚未开展充分评估。本研究针对不同人类干扰强度、区域与时间尺度下的淡水水体及其草本大型水生植物（herbaceous macrophytes），系统解析了其氮磷化学计量比特征。相较于低人类干扰环境，高人类干扰环境中的淡水水体与大型水生植物的氮、磷浓度更高，氮磷比更低；富营养化梯度下的时空比对进一步验证了该结论。在中国区域内，淡水生态系统的氮、磷浓度与人口密度呈显著正相关，而氮磷比则与人口密度呈显著负相关。本研究结果显示，受人类活动干扰的淡水生态系统中，磷的积累速率快于氮；通过淡水径流输入，该现象可能对河口与近岸海域的食物网及生物地球化学循环造成显著影响，同时也进一步凸显了修复此类淡水生态系统的必要性与重要性。