Xia Biqing, Li Sisi, Mei Zhigang, Shen Wangzheng, Mi Menghan, Qiang Ziqi, Zhang Liang
Hubei Provincial Engineering Research Center of Non-Point Source Pollution Control, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430077, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Key Laboratory for Environment and Disaster Monitoring and Evaluation of Hubei, Jianghan Plain-Honghu Lake Station for Wetland Ecosystem Research, Wuhan, 430077, China.
Hubei Provincial Engineering Research Center of Non-Point Source Pollution Control, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430077, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Key Laboratory for Environment and Disaster Monitoring and Evaluation of Hubei, Jianghan Plain-Honghu Lake Station for Wetland Ecosystem Research, Wuhan, 430077, China.
J Environ Manage. 2025 Mar;376:124555. doi: 10.1016/j.jenvman.2025.124555. Epub 2025 Feb 17.
Riparian zones, which are critical interfaces between terrestrial and aquatic ecosystems, are essential for biodiversity, water quality, and landscape stability but are increasingly threatened by anthropogenic activities. The Yangtze River is the longest river in Asia, the riparian zones of which are highly affected by humans, however, they are less studied in terms of pollution change and distribution, which hinders efficient eco-environmental management. This study explored land use and nitrogen and phosphorus non-point source pollution variations in the middle and lower Yangtze River riparian zones from 1995 to 2015 and identified critical risky segments as management priorities. The results revealed great human interventions: Agricultural and constructed lands accounted for 55.2% and 10.2% of the riparian zones, respectively, in 2015, whereas wetlands declined by 2.5% per decade. Using a modified export coefficient model considering terrestrial, climatic, and socioeconomic variations, we found that the nitrogen and phosphorus loads from the riparian zones exhibited a general decline over the two decades, but increased in certain segments due to urbanization. Approximately 10% of the segments contributed over 40% of the nutrient loads. In addition, some river segments with high nutrient loads coincided with ecologically sensitive zones with higher water-quality requirements. Hence, we identified critical riparian zones with higher pollution reduction requirements and management priorities, primarily in the middle reaches of the Yangtze River. This study integrates pollution-load mapping with water-quality target consideration, guiding resource allocation for pollution-control measures, and thus promoting the sustainable management of a key eco-environmental system in Asia.
河岸带是陆地和水生生态系统之间的关键界面，对生物多样性、水质和景观稳定性至关重要，但日益受到人为活动的威胁。长江是亚洲最长的河流，其河岸带受人类影响很大，然而，在污染变化和分布方面的研究较少，这阻碍了有效的生态环境管理。本研究探讨了1995年至2015年长江中下游河岸带的土地利用以及氮磷非点源污染变化，并确定关键风险段作为管理重点。结果显示人类干预程度很大：2015年，农业用地和建设用地分别占河岸带的55.2%和10.2%，而湿地每十年减少2.5%。使用考虑陆地、气候和社会经济变化的修正输出系数模型，我们发现河岸带的氮磷负荷在二十年间总体呈下降趋势，但由于城市化，某些地段有所增加。约10%的地段贡献了超过40%的养分负荷。此外，一些养分负荷高的河段与水质要求较高的生态敏感区重合。因此，我们确定了污染减排要求较高的关键河岸带和管理重点，主要位于长江中游。本研究将污染负荷制图与水质目标考虑相结合，指导污染控制措施的资源分配，从而促进亚洲关键生态环境系统的可持续管理。
