水文变化和人类活动如何控制密西西比河流域上部河流出口的时空变化?
Qianyu Zhao1,2, Bin Peng1,3,4,5, Zewei Ma1,2,4
1Agroecosystem Sustainability Center, Institute for Sustainability, Energy, and Environment, University of Illinois Urbana-Champaign, Urbana, Illinois 61820, United States.
Environmental science & technology
|December 20, 2025
概括
来自农业的污染在密西西比河上流盆地 (UMRB) 正在恶化. 人类活动和降雨模式的变化都增加了酸盐出口,影响了水质.
科学领域:
- 环境科学 环境科学
- 水文学的水文学
- 农业科学 农业科学
背景情况:
- 从农业流域过度出口气是一个主要的水质问题.
- 上密西西比河流域 (UMRB) 显著促进下游的高和低氧.
- 了解营养动态对于有效的水资源管理至关重要.
研究的目的:
- 为了研究河流酸盐加上酸盐 (NO3- + NO2--N) 在UMRB.出口的时空动态.
- 量化人类活动和水文变量的对NO3- + NO2--N出口变化的影响.
- 确定出口驱动因素的区域模式.
主要方法:
- 在12位数的水文单位代码 (HUC12) 下水域区规模上分析河流NO3+NO2出口.
- 两个时期的出口比较:2001-2005年和2016-2020年.
- 解开人类活动和水文变异性对观测变化的贡献.
主要成果:
- 酸盐加酸盐 (NO3- + NO2--N) 产量在2001-2005年至2016-2020年期间在UMRB中平均增加9.7公斤/公/年.
- 人类活动贡献了4.8公斤/公/年,而水文变化贡献了4.9公斤/公/年.
- 观察到不同的区域模式,北部和西部的UMRB受两个因素的影响,东部和中部地区主要受到水文的影响.
- 农业来源占NO3- + NO2--N负载的80%以上.
结论:
- 在UMRB中存在出口增加的热点,由人类活动和水文变化的结合驱动.
- 农业实践仍然是负荷的主要来源.
- 这些发现为制定有针对性的流域管理战略提供了关键的见解,以减轻营养损失和改善水质.
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