학술논문
1960年以来赣江流域生态径流变异机制及生态效应研究 / Study on variation mechanism and ecological effect of eco-flows in the Ganjiang River Basin since 1960
Document Type
Academic Journal
Author
段红鑫; 孔志岗; 叶许春; 袁燕萍; 刘婷婷; 李相虎; 张增信; DUAN Hongxin; KONG Zhigang; YE Xuchun; YUAN Yanping; LIU Tingting; LI Xianghu; ZHANG Zengxin
Source
水利水电技术(中英文) / Water Resources and Hydropower Engineering. 54(12):178-188
Subject
Language
Chinese
ISSN
1000-0860
Abstract
[目的]在全球变化背景下,科学理解流域生态径流变异机制,对优化水资源调控方案和提高抗旱减灾效果至关重要.[方法]基于赣江流域上、中、下游3个水文站1960-2018年时间序列不等的逐日径流量,结合流量过程线计算的生态赤字与生态剩余指标,研究分析了赣江流域的生态径流的变异特征.在此基础上,通过计算标准化降水蒸发系数(SPEI)与生物多样性指数(SI)及其与生态径流指标的拟合关系,探讨了赣江流域生态径流变化的驱动机制和生态响应.[结果]研究显示:(1)赣江流域上、中、下游之间生态适宜流量差异显著,同一站点在不同月份间的生态适宜流量也极为悬殊.(2)从上游到下游生态赤字变异程度逐渐减小,生态剩余略有增大;各站点生态赤字在较低水平上呈现"高-低-高"的年代际波动特征,生态剩余的整体变化规律则相反.(3)生态剩余与SPEI呈正相关关系,而生态赤字与SPEI呈负相关关系;万安水库修建前后,枯水期与丰水期的赣江中下游生态剩余指标有所提升,平水期生态剩余出现下降.(4)SI与河流生态剩余之间以线性正相关关系为主,而SI与河流生态赤字之间表现为指数负相关关系;各站点SI 在 1985年之前呈现小波动下降趋势,之后波动幅度明显增大.[结论]结果表明:赣江流域近60 a生态径流变化受气候与人类活动影响,气候干湿状况是引起河流生态剩余和生态赤字变化的关键因素,干流水库建设对提升下游河道生态剩余作用明显,河流生物多样性与生态径流变化关系密切.研究结果可为提升赣江流域生态径流变异机制认识、水资源调控措施和水生态建设理论提供科学依据.
[Objective]In the context of global change,scientific understanding of the change mechanism of catchment eco-flows is crucial to local water resources optimization and drought mitigation.[Methods]Based on the daily runoff of the upper,middle and downstream hydro-stations of the Ganjiang River Basin from 1960 to 2018,adaptive range of the eco-flow of the Ganjiang River and the eco-deficit and eco-surplus were calculated according to discharge hydrograph,and the variation characteristics of the eco-flows in the Ganjiang River Basin were quantitatively analyzed.On this basis,the standardized precipitation evaporation index(SPEI)and Shannon index(SI)and their fitting connections with eco-flow indices were calculated,and the driving mech-anism and ecological impact of eco-flows change in the Ganjiang River Basin were further explored.[Results](1)adaptive range of eco-flows varies significantly among the upper,middle and downstream of the Ganjiang River Basin,and the ecological suitable flow at the same station also varies greatly in different months.(2)The degree of eco-deficit variance steadily decreases from upstream to downstream,whereas the degree of eco-surplus variation slightly increases.The eco-deficit of each site showed the characteristics of"high-low-high"interdecadal fluctuation at a low level,while the change pattern of eco-surplus was oppo-site.(3)Eco-surplus shows a positive correlation with SPEI,while negative correlation was observed for eco-deficit.The eco-surplus of the middle-lower stream of the Ganjiang River increased during dry and wet periods before and after the construction of Wan'an Reservoir,while it decreased during the normal water period.(4)The relationship between SI and the eco-surplus main-ly shows a linear positive correlation,while the relationship between SI and eco-deficit is better represented by an exponential negative correlation.The SI of each station showed a slight downward fluctuation before 1985,and the fluctuation amplitude in-creased significantly thereafter.[Conclusion]The eco-flow changes of in the Ganjiang River Basin in the past 60 years were af-fected by climate and human activities.The dry/wet climate conditions are the key factors causing changes in river eco-flows.The construction of main stream reservoirs have a significant impact on enhancing the eco-surplus of downstream rivers.The biodiversity of rivers is closely correlated to the change of eco-flows.The research result provide a scientific basis for the improved understanding of eco-flows variation mechanism,water resource optimization,and water ecological construction theory in the Ganjiang River Basin.
[Objective]In the context of global change,scientific understanding of the change mechanism of catchment eco-flows is crucial to local water resources optimization and drought mitigation.[Methods]Based on the daily runoff of the upper,middle and downstream hydro-stations of the Ganjiang River Basin from 1960 to 2018,adaptive range of the eco-flow of the Ganjiang River and the eco-deficit and eco-surplus were calculated according to discharge hydrograph,and the variation characteristics of the eco-flows in the Ganjiang River Basin were quantitatively analyzed.On this basis,the standardized precipitation evaporation index(SPEI)and Shannon index(SI)and their fitting connections with eco-flow indices were calculated,and the driving mech-anism and ecological impact of eco-flows change in the Ganjiang River Basin were further explored.[Results](1)adaptive range of eco-flows varies significantly among the upper,middle and downstream of the Ganjiang River Basin,and the ecological suitable flow at the same station also varies greatly in different months.(2)The degree of eco-deficit variance steadily decreases from upstream to downstream,whereas the degree of eco-surplus variation slightly increases.The eco-deficit of each site showed the characteristics of"high-low-high"interdecadal fluctuation at a low level,while the change pattern of eco-surplus was oppo-site.(3)Eco-surplus shows a positive correlation with SPEI,while negative correlation was observed for eco-deficit.The eco-surplus of the middle-lower stream of the Ganjiang River increased during dry and wet periods before and after the construction of Wan'an Reservoir,while it decreased during the normal water period.(4)The relationship between SI and the eco-surplus main-ly shows a linear positive correlation,while the relationship between SI and eco-deficit is better represented by an exponential negative correlation.The SI of each station showed a slight downward fluctuation before 1985,and the fluctuation amplitude in-creased significantly thereafter.[Conclusion]The eco-flow changes of in the Ganjiang River Basin in the past 60 years were af-fected by climate and human activities.The dry/wet climate conditions are the key factors causing changes in river eco-flows.The construction of main stream reservoirs have a significant impact on enhancing the eco-surplus of downstream rivers.The biodiversity of rivers is closely correlated to the change of eco-flows.The research result provide a scientific basis for the improved understanding of eco-flows variation mechanism,water resource optimization,and water ecological construction theory in the Ganjiang River Basin.