Nature – Qi et al. (2025): Carbonate weathering enhances nitrogen assimilatory uptake in rivers globally
Hongkai Qi, Yi Liu, Haoran Wang, Xingxing Kuang, Aditya Nugraha Putra, Jiu Jimmy Jiao & Jianping Gan, IN: Nature Geoscience, https://doi.org/10.1038/s41561-025-01680-w
Bedrock composition, in particular the proportion of carbonate, can influence the dissolved inorganic carbon concentration and also the carbonate chemistry of rivers, but its effects on the nitrogen cycle in rivers are usually overlooked. Here the authors present geochemical composition measurements of rivers across the Pearl River Basin in China that show that dissolved organic nitrogen (DON) is positively correlated with dissolved inorganic nitrogen and follows the variation in solar radiation in the carbonate-dominated region during the wet season, but not in the non-carbonate-dominated region.