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水电梯级开发真的破坏下游河段营养盐情势吗?

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Science Bulletin 2024年第5期69卷 661-670页

作者：陈求稳陈宇琛林育青张建云倪晋仁夏军肖琳冯韬马宏海 State Key Laboratory of Hydrology-Water Resources&Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China Center for Eco-Environment Research Nanjing Hydraulic Research InstituteNanjing 210029China Yangtze Institute for Conservation and Green Development Nanjing 210024China School of the Environment Nanjing UniversityNanjing 210008China The Key Laboratory of Water and Sediment Sciences Ministry of EducationPeking UniversityBeijing 100091China State Key Laboratory of Water Resources and Hydropower Engineering Sciences Wuhan UniversityWuhan 430072China

river damming is believed to largely intercept nutrients,particularly retain more phosphorus(P)than nitrogen(N),and thus harm primary productivity,fishery catches,and food security downstream,which seriously constrain global hydropower development and poverty relief in undeveloped regions and can drive geo-political disputes between nations along trans-boundary *** this study,we investigated whether reservoirs can instead improve nutrient regimes *** measured different species of N and P as well as microbial functions in water and sediment of cascade reservoirs in the upper Mekong river over 5 years and modelled the influx and outflux of N and P species in each *** partially retaining total N and total P,reservoirs increased the downstream flux of ammonium and soluble reactive phosphorus(SRP).The increase in ammonium and SRP between outflux and influx showed positive linear relationships with the hydraulic residence time of the cascade reservoirs;and the ratio of SRP to dissolved inorganic nitrogen increased along the reservoir *** lentic environment of reservoirs stimulated algae-mediated conversion of nitrate into ammonium in surface water;the hypoxic condition and the priming effect of algae-induced organic matter enhanced release of ammonium from sediment;the synergy of microbial phosphorylation,reductive condition and sediment geochemical properties increased release of *** study is the first to provide solid evidence that hydropower reservoirs improve downstream nutrient bioavailability and N-P balance through a process of retention-transformation-transport,which may benefit primary *** findings could advance our understanding of the eco-environmental impacts of river damming.

关键词： river damming Biogeochemical cycle Nitrogen Phosphorus Ecological impacts

damming effects on dissolved inorganic carbon in different kinds of reservoirs in Jialing river,Southwest China

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Acta Geochimica 2017年第4期36卷 581-597页

作者： Gaoyang Cui Xiaodong Li Qinkai Li Jun Huang Yuele Tao Siqi Li Jun Zhang State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081People's Republic of China University of Chinese Academy of Sciences Beijing 100049People's Republic of China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072People's Republic of China

To assess the effects of river damming on dissolved inorganic carbon in the Jialing river, a total of 40 water samples, including inflow, outflow, and stratified water in four cascade reservoirs(Tingzikou, Xinzheng,Dongxiguan, Caojie) were collected in January and July,2016. The major cations, anions, and δ^(13)C_(DIC) values were analyzed. It was found that the dissolved compositions are dominated by carbonate weathering, while sulfuric acids may play a relatively important role during carbonate weathering and increasing DIC concentration. Different reservoirs had variable characteristics of water physiochemical stratification. The DIC concentrations of reservoir water were lower in summer than those in winter due to the dilute effects and intensive aquatic photosynthesis, as well as imported tributaries. The δ^(13)C_(DIC) values in Tingzikou Reservoir were higher during summer than those in winter,which indicated that intensive photosynthesis increased the δ^(13)C_(DIC) values in residual water, but a similar trend was not obvious in other reservoirs. Except for in Xinzheng Reservoir, the δ^(13)C_(DIC) values in inflow and outflow reservoir water were lower than those in the surface water of stratified sampling in summer. For stratified sampling, it could be found that, in summer, the Tingzikou Reservoir δ^(13)C_(DIC) values significantly decreased with water depthdue to the anaerobic breakdown of organic matter. The significant correlation(priver exhibited natural river features rather than typical lake features due to

关键词： river damming Water chemistry Reservoir types Dissolved inorganic carbon isotope composition DIC concentration

Inducing Flow Velocities to Manage Fish Reproduction in Regulated rivers

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Engineering 2021年第2期7卷 178-186页

作者： Qiuwen Chen Jianyun Zhang Yuchen Chen Kangle Mo Jun Wang Lei Tang Yuqing Lin Lei Chen Yong Gao Wei Jiang Yuxin Zhang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China Center for Eco-Environmental Research Nanjing Hydraulic Research InstituteNanjing 210029China Yangtze Institute for Conservation and Green Development Nanjing 210029China Chinese Sturgeon Research Institute China Three Gorges CorporationYichang 443000China Chongqing Jiaotong University Chongqing 400074China

Conservation of endangered or economic fish and control of invasive fish is a great challenge of hydraulic engineering *** velocity has been recognized to affect the spawning of fishes delivering drifting eggs in ***,solid scientific supports and associated mechanisms to establish quantitative relations between flow velocity and fish reproduction,taking into account spawning,fertilizing,hatching,as well as surviving,are *** this paper,we quantified the relationship between flow velocity and reproduction of Chinese carps through both lab and field *** results showed that a minimum velocity was required to trigger Hypophthalmichthys molitrix(***)releasing eggs,and a velocity range was preferred to sustain spawning ***,the embryo incubation and larvae development of *** were found to be inhibited with the increase in flow *** the requirements of spawning and hatching,as well as larvae surviving,an optimized flow velocity processes was identified for the reproduction of *** in *** findings were of great significance to the adaptive operation of reservoirs to create reasonable and precise ecological flows for managing fish reproduction,as shown by the promising results in the engineering application to the Three Gorges Reservoir.

关键词： river damming Chinese carps Population management Ecological flow Yangtze river