Nakdong River Environment Research Center, National Institute of Environmental Research, Goryeong 40103, Korea.
Geum River Environment Research Center, National Institute of Environmental Research, Okcheon 29027, Korea.
Int J Environ Res Public Health. 2018 Oct 24;15(11):2348. doi: 10.3390/ijerph15112348.
Flow regulation is one of the most common anthropogenic factors affecting rivers worldwide. In Korea, 16 weirs were constructed along four major rivers from 2009 to 2012. This study aimed to elucidate initial changes in physical, chemical, and biological variables after the construction of consecutive weirs on the Nakdong River, a major large river system. Water quality variables and phytoplankton cell densities were investigated at eight representative sites and compared with the data recorded before the weir construction. There were spatial and temporal changes in the hydraulic retention time (HRT), total phosphorus (TP), and chlorophyll concentrations among the eight weir sections. HRT increased after the weir construction, while TP and chlorophyll tended to decrease from the middle to lower section of the Nakdong River. Furthermore, differences were observed in the phytoplankton community composition between 2006⁻2007 and 2013. There was a marginal decrease in the duration of centric diatom () blooms after weir construction. However, proliferated more extensively during summer and autumn than it did before the weir construction. Our results suggest that changes in hydrological factors, in response to consecutive weir construction, may contribute to greater physical, chemical, and ecological variability.
水流调节是影响全球河流的最常见人为因素之一。在韩国，2009 年至 2012 年期间，在四条主要河流上建造了 16 座水坝。本研究旨在阐明在韩国主要大河系统——纳克鲁德河（Nakdong River）上连续建造水坝后，物理、化学和生物变量的初始变化。在八个具有代表性的地点调查了水质变量和浮游植物细胞密度，并将其与水坝建设前记录的数据进行了比较。在八个水坝段之间，水力停留时间（HRT）、总磷（TP）和叶绿素浓度存在时空变化。水坝建设后，HRT 增加，而 TP 和叶绿素则从纳克鲁德河的中游到下游呈下降趋势。此外，2006-2007 年和 2013 年之间浮游植物群落组成也存在差异。水坝建设后，有壳硅藻类（）的繁殖期略有缩短。然而，比水坝建设前更广泛地在夏季和秋季繁殖。我们的结果表明，连续建造水坝导致的水文因素变化可能导致更大的物理、化学和生态变异性。
