引用本文: | 徐闯,刘广州,陈晓宏.珠江流域东江(东莞段)溶解氧时空变化及其影响因素.湖泊科学,2022,34(5):1540-1549. DOI:10.18307/2022.0510 |
| Xu Chuang,Liu Guangzhou,Chen Xiaohong.Spatiotemporal variations and influencing factors of river dissolved oxygen in Dongguan section of Dongjiang River, Pearl River Basin. J. Lake Sci.2022,34(5):1540-1549. DOI:10.18307/2022.0510 |
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摘要: |
溶解氧是水生生态系统健康程度的重要度量指标,研究溶解氧时空变化及其影响因素对揭示河流溶解氧动态过程和理解水体生物地球化学循环具有重要意义. 当前,许多河流均存在溶解氧偏低问题,严重影响河流水质. 基于此,收集了珠江流域东江(东莞段)上游桥头、中游樟村和下游沙田泗盛3个水质监测站的实测资料,采用折线图和箱型图分析溶解氧在月、季节和年际时间尺度下的变化规律及其空间差异; 采用最大信息系数、交叉小波转换和多元线性回归3种方法解析溶解氧时空变化的影响因素. 结果表明:空间分布上,溶解氧浓度从上游到下游逐渐降低,低值区分布在入海口处的沙田泗盛站,多年平均溶解氧浓度仅为3.11 mg/L. 时间变化上,2011—2019年溶解氧主要在11.64个月的周期下循环变化. 溶解氧展现出明显的季节性. 3个站点丰水期溶解氧浓度比枯水期分别降低1.68、2.03和1.77 mg/L. 驱动因素上,溶解氧的时空变化受到多个因素的综合作用. 桥头站和樟村站水质较好,水温是这两个站点溶解氧时空变化的主要影响因素. 其主要在8~16个月的周期上调控溶解氧变化,在两个站点分别可以解释溶解氧整体变化的70%和57%. 沙田泗盛站受多条支流汇入的影响,水体中硝化和氧化作用耗氧增强,加之悬浮物遮光效应,使得该处的溶解氧浓度降低. |
关键词: 溶解氧 时空变化 调控因素 东江(东莞段) 珠江流域 |
DOI:10.18307/2022.0510 |
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基金项目:国家重点研发计划项目(2017YFC0405900)和国家自然科学基金项目(51861125203, U1911204)联合资助 |
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Spatiotemporal variations and influencing factors of river dissolved oxygen in Dongguan section of Dongjiang River, Pearl River Basin |
Xu Chuang1, Liu Guangzhou2, Chen Xiaohong1
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1.School of Civil Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China;2.Institute of Water Environment, Hubei Academy of Ecological Environment Sciences, Wuhan 430072, P. R. China
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Abstract: |
Dissolved oxygen (DO) is a vital metric indicating aquatic ecosystem health. Exploring the spatiotemporal variations and influencing factors of DO is of great significance to reveal the river DO dynamics and to understand the river biogeochemical cycle. Presently many rivers have a problem of low DO, which seriously affects the river water quality. This study collected data of three water quality monitoring stations in the upper reaches of Qiaotou, the middle reaches of Zhangcun and the lower reaches of Shatiansisheng in Dongguan section of Dongjiang River, Pearl River Basin. The DO variations on monthly, seasonal and inter-annual timescales and corresponding spatial heterogeneity were analyzed using broken line and box diagrams. Influencing factors of DO variations were explored by three approaches including maximum information coefficient, cross wavelet transform and multiple linear regression. The results showed that DO concentration gradually decreased from upstream to downstream. The low DO values (3.11 mg/L) appeared in the Shatiansisheng station near the estuary. Temporally, DO changed in a cycle of 11.64 months from 2011 to 2019, exhibiting obvious seasonality. In wet seasons DO concentrations at three stations were 1.68, 2.03 and 1.77 mg/L lower than those in dry seasons, respectively. The water qualities of Qiaotou and Zhangcun stations were better. Water temperature was the main factor affecting the spatiotemporal variations of DO in these two stations. Water temperature regulated DO changes in a cycle of 8-16 months and accounted for 70% and 57% of the total DO changes at these two stations, respectively. Impacted by multiple tributaries inflows, nitrification and oxidation processes, oxygen demands were strengthened in Shatiansisheng station, coupled with the shading effect of suspended solids, resulting in a low DO concentration. |
Key words: Dissolved oxygen spatiotemporal variation influencing factors Dongguan section of Dongjiang River Pearl River Basin |