评估农业流域的水质趋势,优先实施管理实践
James Webber1, Jeffrey Chanat1, John Clune2
1U.S. Geological Survey, Virginia and West Virginia Water Science Center, Richmond, Virginia, USA.
概括
农业流域的管理实践 (MP) 并没有持续减少营养和沉积物负载. 增加的营养应用可能会抵消MP的益处,强调需要长期监测以评估有效性.
科学领域:
- 环境科学 环境科学
- 农业科学 农业科学
- 水资源管理 水资源管理
背景情况:
- 农业流域经常使用自愿管理实践 (MP) 来减轻非点源污染.
- 这些管理实践对水质的实际影响仍然不确定.
- 切萨皮克湾的流域优先考虑MP的实施,以改善水质.
研究的目的:
- 评估管理实践 (MP) 在三个农业切萨皮克湾流域对水质的影响.
- 确定影响营养和沉积物负载的因素,包括MP,气候,土地利用和营养投入.
- 评估国会议员在改善水质方面的长期表现.
主要方法:
- 解释了1985-2020年史密斯溪 (VA),上切斯特河 (MD) 和Conewago溪 (PA) 的水质数据.
- 综合了有关国会议员,气候,土地利用和营养投入的数据.
- 利用史密斯溪的36年时间序列模型来分析流量正常化总负荷.
主要成果:
- 自2010年代初以来,MP的增加并不总是导致营养和沉积物负载的减少.
- 史密斯溪和上切斯特河显示营养和沉积物负载增加或稳定.
- 康涅瓦戈溪的沉积物负载和一些营养负载有所下降.
- 在史密斯溪,肥料应用时间的变化与改变的总负荷相关.
结论:
- 在改善水质方面,国会议员的有效性并不能始终被确定.
- 增加营养物质的应用可能会抵消管理实践的积极影响.
- 减少肥和肥料的应用可能是实现营养负载改善的关键.
- 长期监测研究对于评估管理实践的表现至关重要.
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