| 摘要: |
| 为探讨极端干旱气候条件下湖库型水源地水生态环境特征及调水工程对其产生的影响,以太湖流域湖西丘陵山区典型湖库型水源地——沙河水库为例,基于统计方法和机理模型,探讨水质水生态对干旱气候和调水输入的响应特征。研究结果表明：受2022~2023年流域严重干旱事件影响,沙河水库水位下降对透明度和总氮指标影响较为显著,水库基本达到了中营养到轻度营养化状态,其中叶绿素a、水温、高锰酸盐指数、总磷对藻密度影响最大；沙河水库藻类群落时空分布差异显著,且不同藻类与特定环境因子相关性差异明显,底栖动物群落构成全年均以昆虫纲生物量占据优势,不同监测点位的优势物种也有差异。底栖生物总量与物理参数和光照条件呈正相关,而底栖生物多样性则与营养负荷呈正相关；现状补水前后水库水质高锰酸盐指数和总氮浓度短期有一定升高,逐渐趋于稳定状态。基于PCLake+模型模拟显示,不同类别水质输入影响下,叶绿素a相较于总氮、总磷受到外界扰动的响应相对迟缓,且影响随着补水结束和自我调节逐渐减弱。 |
| 关键词: 湖库型水源地 干旱影响 调水输入 水质 水生态 PCLake+模型 |
| DOI： |
| 分类号:X524 |
| 基金项目:江苏省水利科技项目（2023025）、国家重点研发计划项目（2023YFC3006601）、国家自然科学基金项目（52309030）、浙江省水利厅科技计划项目（RA2201） |
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| Characteristics of Hydro-ecological Environment and Impact of Water Transfer Input in Lake-Reservoir Type Water Source Areas under Drought Background |
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Wenqi Wang1, Zongzhi Wang1, Ying Bai1, Lang Tan1, Xinyu Chen2, Fuhe Yu2, Zuxing Di2
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1.Hydrology and Water Resources Department,Nanjing Hydraulic Research Institute,Jiangsu,Nanjing;2.Water Resources Bureau of Liyang,Jiangsu,Liyang
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| Abstract: |
| In order to explore the characteristics of hydro-ecological environment of lake-reservoir type water source area under extreme drought conditions and the impact of water transfer project on it, Shahe Reservoir, a typical lake-reservoir type water source area in the western hilly and mountainous area of the Taihu Lake Basin, was taken as an example to explore the response characteristics of water quality and water ecology to drought condition and water transfer input, based on statistical method and mechanism model. The results indicate that: due to the severe drought events in the basin from 2022 to 2023, the decrease in water level in Shahe Reservoir has a significant impact on transparency and TN indicators. The reservoir has basically reached a state of moderate to mild eutrophication, with chlorophyll-a, water temperature, permanganate index, and total phosphorus having the greatest impact on algal density; there are significant differences in the spatiotemporal distribution of algal communities in Shahe Reservoir, and the correlation between different algae and specific environmental factors varies significantly. The composition of benthic animal communities is dominated by insect biomass throughout the year, and the dominant species at different monitoring points also differ. The total amount of benthic organisms is positively correlated with physical parameters and lighting conditions, while benthic biodiversity is positively correlated with nutrient load; the permanganate index and total nitrogen concentration of the reservoir have increased in the short term before and after the current water supplement project, gradually stabilizing. Based on the PCLake+ model simulation, it is shown that under the influence of different types of water quality inputs, chlorophyll-a responds relatively slowly to external disturbances compared to total nitrogen and total phosphorus, and the effect gradually weakens with the end of water replenishment and self-regulation of the reservoir. |
| Key words: drinking water sources in lake reservoirs drought impact water supplement water quality aquatic ecosystem PCLake+ |
