| 摘要: |
| 固城湖是长江下游受闸站调控的重要通江湖泊，在水量调蓄、城乡供水、农业灌溉、水产养殖以及维系生态平衡方面具有重要作用。本研究分析了固城湖2014~2020年水文情势和湖泊水质变化特征，探讨了水文情势对固城湖水质变化的影响。研究结果表明：（1）固城湖水文情势受水阳江入流、降水以及闸站调控、临时驾设泵站补水等共同作用，相比于多年平均水位，近年来冬春湖泊水位抬高近2m，全年最低水位出现时期由冬春推迟到初夏，湖泊天然水文情势受到改变。（2）固城湖总氮、总磷、氨氮、高锰酸盐指数浓度多年平均值分别为0.90 mg/L、0.04 mg/L、0.16 mg/L和4.00 mg/L，叶绿素a浓度0.01 mg/L；季节性Kendall变化趋势检验表明，水体氮磷营养盐浓度和高锰酸盐指数呈下降趋势，叶绿素a浓度和营养指数呈上升趋势，湖泊由中营养向富营养状态过渡。（3）入湖水量与透明度呈极显著负相关关系，和总磷浓度、叶绿素a、营养指数呈显著正相关关系；月平均水位和高锰酸盐指数、氨氮浓度、总磷浓度呈显著正相关关系。受闸站控制的水文情势变化是固城湖水质变化重要的驱动因子。建议进一步提高固城湖水资源调控能力，保障枯水期和极端干旱条件下生产、生活和生态用水需求；加强流域水体污染防治，提升入湖河流水体水质。 |
| 关键词: 固城湖 通江湖泊 水文情势 水质 水资源调控 |
| DOI： |
| 分类号:TV213.4 |
| 基金项目:江苏省水利科技项目(2019033)；中央级公益性科研院所基本科研业务费项目(Y520001和Y521023) |
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| Temporal variation of hydrological regime and water quality status between 2014~2020 in Gucheng Lake |
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Lu Hai-ming1, Lu Xiao-ping2, Liu Wei-ting1, Wang Kai3, Yao Ya-qin4
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1.State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Resources Institute;2.Management Division of Qinhuai River Hydraulic Engineering of Jiangsu Province;3.: State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Resources Institute;4.Water Bureau of Gaochun District
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| Abstract: |
| As an essential Yangtze river-connected lake regulated by the sluice and pump station, Gucheng Lake played a vital role in water resources regulation, drinking water supply, irrigation, aquaculture, and ecosystem balance maintenance. Temporal variation of hydrology regime and water quality between 2014 and 2020 in Gucheng Lake were investigated, and the effects of hydrological regime on water quality were also explored. Results showed that: (1) The hydrological regime of Gucheng Lake was affected by inflow from Shuiyang River, local precipitation, sluice regulation and artificial replenishment. Compared with multi-years mean water stage, water stage in winter and spring increased about 2m. The period of annual lowest water stage was postponed from winter and spring to early summer. Natural hydrological regime has been changed. (2) Multi-annual mean of TN, TP, NH3-N and CODMn concentrations were 0.90 mg/L, 0.04 mg/L, 0.16 mg/L and 4.00 mg/L respectively. Concentrations of Chlorophyll a fluctuated around 0.01 mg/L. Seasonal Kendall trend test showed that nitrogen and phosphorus nutrients and CODMn witnessed a remarkable decreasing trend, while Chlorophyll a and nutrient index increased. Nutrient index shifted from mesotrophic status to eutrophication. (3) The water inflow of Gucheng Lake was significantly negatively correlated with transparency, and significantly positively correlated with TP, chlorophyll a and nutritional index. Monthly average water level was significantly positively correlated with CODMn, NH3-N and TP. Hydrological regime was the main driving force for the variation of water quality in Gucheng Lake. The capacity of water resources control and regulation was suggested to enhance furtherly to meet water use for daily life, production and ecology during the nonrainy season and extremely drought condition. Strengthening watershed water pollution control and prevention was suggested to improve water quality in the rivers entering Gucheng Lake. |
| Key words: Gucheng Lake Yangtze river-connected lake hydrological regime water quality water resources regulation |
