Nakdong River Environment Research Center, National Institute of Environmental Research, 24-11, Gukgasandan-daero 52, Daegu, 43008, South Korea.
University of Texas-Permian Basin, 4901 E. University Blvd., Odessa, TX, 79762, USA.
Environ Sci Pollut Res Int. 2021 Sep;28(33):45676-45692. doi: 10.1007/s11356-021-12976-w. Epub 2021 Apr 20.
Identifying critical source areas (CSAs) is the first step to effectively managing nonpoint source (NPS) pollution. Increasing variability in climate can affect identification of CSAs. In this study, we identified present and future CSAs of NPS pollution in the Nakdong River watershed and examined how climate change will influence the identification of CSAs. Nine NPS pollution-related factors affecting the watershed environment and water quality were considered. These factors were rescaled through a min-max normalization to propose an index system that ranks basins based on the sensitivity of basins to climate change on identifying CSAs. For analyses, past rainfall was replaced with future rainfall under two RCP scenarios, RCP 2.6 and RCP 8.5. Results showed insignificant differences in the spatial distribution of CSAs between the present and the future and between the future scenarios. Basins that are on or adjacent to the Nakdong River mainstream were mainly identified as CSAs, in addition to many basins of the Geumho and Nam rivers. Highly ranked CSAs including the level 1 CSAs, were mainly distributed in the mid- and downstream areas of the Nakdong River, indicating high need of NPS pollution management. This study can provide a foundation for the effective management of NPS pollution in the present and the future.
识别关键源区（CSAs）是有效管理非点源（NPS）污染的第一步。气候的变化幅度增加可能会影响 CSA 的识别。在这项研究中，我们确定了在南江流域现在和未来的 NPS 污染 CSA，并研究了气候变化将如何影响 CSA 的识别。考虑了 9 个与流域环境和水质有关的 NPS 污染相关因素。这些因素通过最小-最大归一化进行了重新缩放，提出了一个基于流域对 CSA 识别的气候变化敏感性对流域进行排名的指数系统。在分析中，过去的降雨量被未来的降雨量（在 RCP2.6 和 RCP8.5 两种情景下）所取代。结果表明，CSA 在现在和未来之间以及未来情景之间的空间分布没有显著差异。主要识别到处于南江干流或其附近的流域为 CSA，此外还有 Geumho 和 Nam 河的许多流域。排名较高的 CSA，包括一级 CSA，主要分布在南江中下游地区，表明需要对 NPS 污染进行高度管理。本研究可为当前和未来 NPS 污染的有效管理提供基础。
