Abstract:

The nutrient exports including nitrogen (N) and phosphorus (P) within Jiulong River-Xiamen Bay continuum were preliminarily estimated during 2011—2020. The factors which might have a negative impact on the water quality were identified after analyzing the spatial-temporal pattern of nutrient exports. The results showed that the exports of N and P from Jiulong River might decrease recent years while the nutrient exports were still too high to reduce eutrophication within Jiulong River-Xiamen Bay continuum. Anthropogenic activities including livestock breeding and fertilizers application might be the major factors that influence nutrient exports in this area. Specifically, the N export in the North River was the highest and P export in the West River was the highest while the nutrient exports in the South River were always low within the Jiulong River Watershed in the year 2018. The nutrient exports might be controlled by the runoff of the river reach as well as the different pattern of anthropogenic activities. This study proposed a method to estimate and control of nutrient exports in the Jiulong River-Xiamen Bay continuum, providing significant insights into water management for local government.