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Incorporation of GIS Based Program into Hydraulic Model for Water Level Modeling on River Basin 被引量:5
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作者 Ali Haghizadeh Lee Teang Shui +1 位作者 Majid Mirzaei Hadi Memarian 《Journal of Water Resource and Protection》 2012年第1期25-31,共7页
Water resources management usually requires that hydraulic, ecological, and hydrological models be linked. The Hy- drologic Engineering Center River Analysis System (HEC-RAS) hydraulic model and the Hydrologic Enginee... Water resources management usually requires that hydraulic, ecological, and hydrological models be linked. The Hy- drologic Engineering Center River Analysis System (HEC-RAS) hydraulic model and the Hydrologic Engineering Center Geospatial River Analysis System (HEC-GEORAS), imitates flow and water profiles in the Neka river basin’s downstream flood plain. Hydrograph phases studied during the flood seasons of 1986-1999 and from 2002-2004 were used to calibrate and verify the hydraulic model respectively. Simulations of peak flood stages and hydrographs’ evaluations are congruent with studies and observations, with the former showing mean square errors between 4.8 - 10 cm. HECRAS calculations and forecast flood water levels. Nash-Sutcliffe effectiveness (CR3) is more than 0.92 along with elevated levels of water which were created with some effectiveness (CR5) of 0.94 for the validation period. The coupled two models show good performance in the water level modeling. 展开更多
关键词 HEC-RAS HEC-GEORAS Nash-Sutcliffe Neka river Water level MODELING
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Estimation of Peak Water Level in Pearl River Estuary under the Background of Sea Level Rise
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作者 KONG Lan CHEN Xiao-hong +1 位作者 ZHUANG Cheng-bin CHEN Dong-wei 《Meteorological and Environmental Research》 CAS 2012年第11期44-46,共3页
[Objective] The study aimed to predict the peak water level in Pearl River Estuary under the background of sea level rise. [Method] The changing trends of peak water level at Denglongshan station and Hengmen station w... [Objective] The study aimed to predict the peak water level in Pearl River Estuary under the background of sea level rise. [Method] The changing trends of peak water level at Denglongshan station and Hengmen station were analyzed firstly on the basis of regression models, and then sea level rise in Pearl River Estuary in 2050 was predicted to estimate the 1-in-50-year peak water level in the same year. [Result] Regression analyses showed that the increasing rate of peak water level over past years was 6.3 mm/a at Denglongshan station and 5.8 mm/a at Hengmen station. In addition, if sea level will rise by 20, 30 and 60 cm respectively in 2050, it was predicted that the 1-in-50-year peak water level will reach 3.04, 3.14 and 3.44 m at Denglongshan station, and 3.19, 3.29 and 3.59 m at Hengmen station separately. [Conclusion] The estimation of peak water level in Pearl River Estuary could provide theoretical references for water resources planning. 展开更多
关键词 Sea level rise Pearl river Estuary Peak water level China
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Late Quaternary diatom and sea level changes in estuarine plain of the Jiulong River 被引量:3
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作者 Chen Wenrui, (State Pilot Laboratory of Coast and Island Exploitation, Naning University, Naning 210093, China)Lan Dongzhao and Chen Chenghui (Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1998年第4期509-518,共10页
Four units and twenty-four zones of diatom have been discerned in the Borehole ZK5 in the estuarine plain of the Jiulong River, Fujian Province. Comprehensive analysis of these, together with microbiological assemblag... Four units and twenty-four zones of diatom have been discerned in the Borehole ZK5 in the estuarine plain of the Jiulong River, Fujian Province. Comprehensive analysis of these, together with microbiological assemblages and age determinations in some other boreholes, shows that during the Late Wurm Glacial, sea level of the study area rose and fell frequently, but had principally been in the environments of estuary-bay. This mainly resulted from the tectonic subouction. In this period 3 low sea levels occurred. at 18, 16 and 12 kaBP respectively. During Holocene, sea weter intruded massively and the sea level over the transgnaion maximum had been 5-10 m higher than that of the present. 展开更多
关键词 Late Quaternary DIATOM sea level change estuarine plain the Jiulong river
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Projection of the Zhujiang(Pearl) River Delta's potential submerged area due to sea level rise during the 21st century based on CMIP5 simulations 被引量:4
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作者 XIA Jiangjiang YAN Zhongwei +6 位作者 ZHOU Wen FONG Soi Kun LEONG Ka Cheng TANG Iu Man CHANG S W LEONG W K JIN Shaofei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第9期78-84,共7页
Projections of potential submerged area due to sea level rise are helpful for improving understanding of the influence of ongoing global warming on coastal areas. The Ensemble Empirical Mode Decomposition method is us... Projections of potential submerged area due to sea level rise are helpful for improving understanding of the influence of ongoing global warming on coastal areas. The Ensemble Empirical Mode Decomposition method is used to adaptively decompose the sea level time series in order to extract the secular trend component. Then the linear relationship between the global mean sea level (GMSL) change and the Zhujiang (Pearl) River Delta (PRD) sea level change is calculated: an increase of 1.0 m in the GMSL corresponds to a 1.3 m (uncertainty interval from 1.25 to 1.46 m) increase in the PRD. Based on this relationship and the GMSL rise projected by the Coupled Model Intercomparison Project Phase 5 under three greenhouse gas emission scenarios (representative concentration pathways, or RCPs, from low to high emission scenarios RCP2.6, RCP4.5, and RCP8.5), the PRD sea level is calculated and projected for the period 2006-2100. By around the year 2050, the PRD sea level will rise 0.29 (0.21 to 0.40) m under RCP2.6, 0.31 (0.22 to 0.42) m under RCP4.5, and 0.34 (0.25 to 0.46) m under RCP8.5, respectively. By 2100, it will rise 0.59 (0.36 to 0.88) m, 0.71 (0.47 to 1.02) m, and 1.0 (0.68 to 1.41) m, respectively. In addition, considering the extreme value of relative sea level due to land subsidence (i.e., 0.20 m) and that obtained from intermonthly variability (i.e., 0.33 m), the PRD sea level will rise 1.94 m by the year 2100 under the RCP8.5 scenario with the upper uncertainty level (i.e., 1.41 m). Accordingly, the potential submerged area is 8.57x103 km2 for the PRD, about 1.3 times its present area. 展开更多
关键词 sea level Zhujiang (Pearl) river Delta (PRD) representative concentration pathways (RCPs) CMIP5 submerged area Ensemble Empirical Mode Decomposition (EEMD)
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SEA LEVEL RISE OF THE ZHUJIANG RIVER DELTA AND NEOTECTONICS
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作者 曾昭璇 刘南威 +6 位作者 胡男 丘世钧 黄山 李平日 方国祥 黄光庆 祝功武 《Chinese Geographical Science》 SCIE CSCD 1993年第1期46-52,共7页
A linear regression analysis of 28 selected tide-gauge stations of the Zhujiang Estuary shows that there has been a tendency of local sea level rise at a rate of 2.028 mm per year. The origin of the variation is signi... A linear regression analysis of 28 selected tide-gauge stations of the Zhujiang Estuary shows that there has been a tendency of local sea level rise at a rate of 2.028 mm per year. The origin of the variation is significantly attributed to the local tectonic movement of discrepant fault-block. Based on this, four types of relative local sea level changes are classified. According to calculation, half of the fertile land, or 800 km2 of the delta plain will have been submerged by sea water by about 2040. This will yield a significant influence on the economic construction and human activities. 展开更多
关键词 SEA level RISE the Zhujiang river DELTA NEOTECTONICS
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Using River Altitude Determined from a SRTM DEM to Estimate Groundwater Levels of the Tokwe and Mutirikwi Watersheds in Zimbabwe
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作者 David Chikodzi Godfrey Mutowo 《Journal of Geographic Information System》 2016年第1期65-72,共8页
Groundwater resources provide most of the domestic water supply in rural Zimbabwe and support poverty reduction through irrigation facilities. Most agricultural and environmental plans need water table depth analysis ... Groundwater resources provide most of the domestic water supply in rural Zimbabwe and support poverty reduction through irrigation facilities. Most agricultural and environmental plans need water table depth analysis as an input in designing best management strategies. There are limited direct measurements of groundwater levels in Zimbabwe due to high costs and the limited human expertise. The study is aimed at coming up with a proof of concept that altitude of rivers as determined by an SRTM digital elevation model can be used to estimate the levels of groundwater in parts of Mutirikwi and Runde sub catchments of southern Zimbabwe. The study also maps the groundwater levels of the area as determined by river altitude from the digital elevation model. Firstly, the groundwater levels for nine boreholes are measured. Secondly, the altitude of a river bed nearest to each borehole site is extracted from a digital elevation model. Finally, the Spearman’s correlation coefficient is used to determine the nature and strength of the relationship between the two variables. Linear regression analysis was also used to obtain the predictive equation of the relationship and its coefficient of determination. After the relationship between groundwater and river altitude is established, 9 new random points of river altitude are generated across the study area interpolated using kriging interpolation to give the estimated altitude of river altitude. The altitude of groundwater is then determined by running the predictive equation Y = 0.8736 * X + 0.852 obtained from regression analysis. The depth to groundwater level of area is obtained by subtracting the determined groundwater altitude from the SRTM DEM. The results show strong positive and statistically significant (ρ = 0.000, α = 0.01) correlation coefficient of 0.971 between measured groundwater levels and altitude of rivers. The regression model shows a coefficient of determination (r2) of 0.975. The research therefore determines that altitude of rivers and use of geostatistics can produce physically plausible estimates of groundwater levels in the study area. 展开更多
关键词 SRTM DEM Groundwater level Kriging Interpolation river Altitude
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Non-stationary water-level fluctuation in China's Poyang Lake and its interactions with Yangtze River 被引量:20
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作者 DAI Xue WAN Rongrong YANG Guishan 《Journal of Geographical Sciences》 SCIE CSCD 2015年第3期274-288,共15页
Seasonal water-level fluctuations (WLF) play a dominate role in lacustrine ecosys- tems. River-lake interaction is a direct factor in changes of seasonal lake WLF, especially for those lakes naturally connected to u... Seasonal water-level fluctuations (WLF) play a dominate role in lacustrine ecosys- tems. River-lake interaction is a direct factor in changes of seasonal lake WLF, especially for those lakes naturally connected to upstream and downstream rivers. During the past decade, the modification of WLF in the Poyang Lake (the largest freshwater lake in China) has caused intensified flood and irrigation crises, reduced water availability, compromised water quality and extensive degradation of the lake ecosystem. There has been a conjecture as to whether the modification was caused by its interactions with Yangtze River. In this study, we investi- gated the variations of seasonal WLF in China's Poyang Lake by comparing the water levels during the four distinct seasons (the dry season, the rising season, the flood season, and the retreating season) before and after 2003 when the Three Gorge Dam operated. The Water Surface Slope (WSS) was used as a representative parameter to measure the changes in river-lake interaction and its impacts on seasonal WLF. The results showed that the magni- tude of seasonal WLF has changed considerably since 2003; the seasonal WLF of the Poy- ang Lake have been significantly altered by the fact that the water levels both rise and retreat earlier in the season and lowered water levels in general. The fluctuations of river-lake in- teractions, in particular the changes during the retreating season, are mainly responsible for these variations in magnitude of seasonal WLF. This study demonstrates that WSS is a rep- resentative parameter to denote river-lake interactions, and the results indicate that more emphasis should be placed on the decrease of the Poyang Lake caused by the lowered water levels of the Yangtze River, especially in the retreating season. 展开更多
关键词 seasonal water-level fluctuations in lakes slope of water surface river-lake interactions Poyang Lake
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Statistical Modeling and Trend Detection of Extreme Sea Level Records in the Pearl River Estuary 被引量:1
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作者 Weiwen WANG Wen ZHOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第3期383-396,共14页
Sea level rise has become an important issue in global climate change studies. This study investigates trends in sea level records, particularly extreme records, in the Pearl River Estuary, using measurements from two... Sea level rise has become an important issue in global climate change studies. This study investigates trends in sea level records, particularly extreme records, in the Pearl River Estuary, using measurements from two tide gauge stations in Macao and Hong Kong. Extremes in the original sea level records (daily higher high water heights) and in tidal residuals with and without the 18.6-year nodal modulation are investigated separately. Thresholds for defining extreme sea levels are calibrated based on extreme value theory. Extreme events are then modeled by peaks-over-threshold models. The model applied to extremes in original sea level records does not include modeling of their durations, while a geometric distribution is added to model the duration of extremes in tidal residuals. Realistic modeling results are recommended in all stationary models. Parametric trends of extreme sea level records are then introduced to nonstationary models through a generalized linear model framework. The result shows that, in recent decades, since the 1960s, no significant trends can be found in any type of extreme at any station, which may be related to a reduction in the influence of tropical cyclones in the region. For the longer-term record since the 1920s at Macao, a regime shift of tidal amplitudes around the 1970s may partially explain the diverse trend of extremes in original sea level records and tidal residuals. 展开更多
关键词 sea level rise extreme climate change extreme value theory Pearl river Estuary
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Water level updating model for flow calculation of river networks
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作者 Xiao-ling WU Xiao-hua XIANG +1 位作者 Li LI Chuan-hai WANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期60-69,共10页
Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up base... Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up based on a three-step method at key nodes, and model correction values were collected from gauge stations. To improve the accuracy of water level and discharge forecasts for the entire network, the discrete coefficients of the Saint-Venant equations for river sections were regarded as the media carrying the correction values from observation locations to other cross-sections of the river network system. To examine the applicability, the updating model was applied to flow calculation of an ideal river network and the Chengtong section of the Yangtze River. Comparison of the forecast results with the observed data demonstrates that this updating model can improve the forecast accuracy in both ideal and real river networks. 展开更多
关键词 plain river network cyclic looped channel network water level updating model hydrodynamic model error correction
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Assessment of Water Scarcity Levels in the Srepok River Basin
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作者 Le Van Linh Tu Anh Nguyen +5 位作者 Nguyen Anh Duc Tran Van Tra Nguyen Thanh Long Dang Dinh Duc Tran Duc Thinh Nguyen Thi Bich 《Open Journal of Modern Hydrology》 CAS 2024年第4期231-249,共19页
Water scarcity has become a pressing global issue, worsening food security, hindering economic development, compromising environmental quality, and threatening human health and other fundamental societal needs. Viet N... Water scarcity has become a pressing global issue, worsening food security, hindering economic development, compromising environmental quality, and threatening human health and other fundamental societal needs. Viet Nam is among the countries severely affected by water scarcity. This study comprehensively assesses the extent and scale of water scarcity in the Srepok River Basin, considering the impacts of water resource allocation, balance, and environmental flows. The areas heavily affected by water scarcity include Ea Hleo, Ea Krong Ana, and several Srepok River branches, with water scarcity periods mainly concentrated in February, March, and April. The influence of climate change has increased the extent and level of water scarcity in the river, affecting an estimated 1.4 million people for at least one month and about 1 million for at least three months. The agricultural sector is significantly affected by water scarcity, with water shortages of 50% according to the baseline scenario and over 60% according to climate change scenarios. 展开更多
关键词 Water Scarcity level Water Balance Climate Change RCP 4.5 Srepok river Basin
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西南高山峡谷区金沙江流域河网结构特征
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作者 关昊哲 冶运涛 +3 位作者 顾晶晶 周政 曹引 蒋云钟 《河海大学学报(自然科学版)》 北大核心 2026年第2期9-17,共9页
为研究金沙江流域河网结构特征,基于ASTER GDEMV3数据与河网密度法提取河网,采用Horton-Stahler分级法结合盒维数、分支比、河长比、侧枝比等指标,分析了金沙江流域的自相似性规律与结构特征及干流形态特征。结果表明:金沙江流域1~6级... 为研究金沙江流域河网结构特征,基于ASTER GDEMV3数据与河网密度法提取河网,采用Horton-Stahler分级法结合盒维数、分支比、河长比、侧枝比等指标,分析了金沙江流域的自相似性规律与结构特征及干流形态特征。结果表明:金沙江流域1~6级河流在结构与拓扑上符合自相似性,而7~8级河流自相似性不明显;盒维数与河网密度在流域尺度上满足自相似性,且上游地区盒维数较小、河网密度较大,下游地区相反,地形因素较气候因素在影响西南高山峡谷型流域(金沙江流域)盒维数与河网密度方面起着主要作用;高山高原区流域河网整体表现出分支比、河长比较大而侧枝比较小的特性;金沙江干流上游坡度缓、弯曲半径较大,中游坡度陡、河道顺直,下游坡度缓、弯曲半径较小,且随着研究河段长度的增大,平均弯曲度、弯曲度极差以及数据离散程度都相应增大,河段弯曲度与河段比降整体上存在反比关系。 展开更多
关键词 西南高山峡谷区 金沙江流域 河网 河流级别 自相似性 弯曲度
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数字孪生长江建设顶层设计与实施保障
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作者 廖志伟 王威 徐照明 《人民长江》 北大核心 2026年第2期1-6,共6页
数字孪生技术作为驱动新阶段水利高质量发展的核心引擎,对提升长江流域治理现代化水平具有战略意义。通过分析数字孪生长江建设的基础,基于当前从试点示范迈向体系化构建的关键阶段,研究提出夯实基础设施、构建孪生平台、深化业务应用... 数字孪生技术作为驱动新阶段水利高质量发展的核心引擎,对提升长江流域治理现代化水平具有战略意义。通过分析数字孪生长江建设的基础,基于当前从试点示范迈向体系化构建的关键阶段,研究提出夯实基础设施、构建孪生平台、深化业务应用、健全支撑保障的系统性顶层设计框架,明确至2027年夯基提能建成数字孪生长江1.0,至2030年迭代优化建成数字孪生长江2.0的“两步走”建设目标,并进一步从项目统筹、任务分工、标准规范、组织保障4个维度提出实施保障策略。研究成果可指导推动数字孪生长江从顶层设计转向落地实施。 展开更多
关键词 数字孪生长江 顶层设计 实施路径 长江流域治理现代化
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沿黄九省(区)科技创新现状及创新效率评价研究
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作者 张爱宁 柴丽霞 李建伟 《甘肃科技纵横》 2026年第1期32-43,共12页
科技创新成为推动经济高质量发展的重要引擎,如何创新驱动黄河流域高质量发展成为重要问题。文章在分析沿黄九省(区)科技创新现状的基础上,运用三阶段DEA方法,测算分析2012—2022年沿黄九省(区)创新效率变动规律。研究表明:(1)沿黄九省(... 科技创新成为推动经济高质量发展的重要引擎,如何创新驱动黄河流域高质量发展成为重要问题。文章在分析沿黄九省(区)科技创新现状的基础上,运用三阶段DEA方法,测算分析2012—2022年沿黄九省(区)创新效率变动规律。研究表明:(1)沿黄九省(区)科技创新投入持续增长但体量较小;(2)沿黄九省(区)科技创新效率总体不高且区域发展不均衡;(3)规模无效率是制约沿黄九省(区)创新效率提升的主要原因;(4)除陕西外,环境因素对其他省(区)创新效率影响显著;(5)R&D经费投入强度对黄河上游地区创新效率具有显著的负向影响。 展开更多
关键词 沿黄九省(区) 创新效率 三阶段DEA 异质性分析
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基于强化学习算法的闸控河网工程水位控制方法
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作者 陈珠亮 孔令仲 +4 位作者 肖洋 张涛涛 冯仲恺 王晓颖 刘子涵 《南水北调与水利科技(中英文)》 北大核心 2026年第1期31-41,共11页
为保障河道网络工程景观功能发挥与供水安全、实现水位稳定控制,传统水位控制方法中基于经验的手动调节和比例-积分(proportional-integral,PI)自动控制算法存在明显局限性,易导致水位调节精度不足、动态过程中振荡现象明显等问题,难以... 为保障河道网络工程景观功能发挥与供水安全、实现水位稳定控制,传统水位控制方法中基于经验的手动调节和比例-积分(proportional-integral,PI)自动控制算法存在明显局限性,易导致水位调节精度不足、动态过程中振荡现象明显等问题,难以满足工程对水位稳定的核心需求。通过构建河道水闸群强化学习训练框架,采用软演员评论家(soft actor-critic,SAC)算法训练水闸控制智能体,以实现水闸群实时高效联合调控。结果表明:经充分训练收敛后,该智能体水力控制性能优异,随机流量扰动引发水位波动时,可快速将水位精准调控至目标值(偏差严格控制在±0.2 m内),调控误差范围较传统PI算法缩小48.8%。相较于PI算法,其核心优势为:水位稳定速度显著提升,动态调节收敛速度加快40%;水闸操作次数大幅减少,闸门动作频次降低32%;环境适应性更强,可在不同水流条件下稳定维持期望水位(PI算法对部分渠池如闸4的水位调控偏差达0.332 m,超出目标范围)。研究证实,基于SAC的强化学习方法为河道网络水位稳定调控提供了创新解决方案,能有效应对随机流量扰动,提升水位调节稳定性与精准度,为河网智能化管理控制提供重要技术支撑,在工程中应用前景广阔。 展开更多
关键词 河网 水位控制 强化学习 SAC算法 闸门调控
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基于稳定同位素技术的新疆伊犁河上游水库鱼类营养结构研究
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作者 万朝阳 彭亮 +5 位作者 张文敏 张燕 张辉 陶玲 代梨梨 李谷 《生态科学》 北大核心 2026年第1期98-105,共8页
为探究新疆高山冰雪融水水源水库鱼类群落营养结构特征,以新疆伊犁河上游恰甫其海和温泉水电站水库为研究对象,于2021年开展鱼类资源调查,并利用稳定同位素技术对鱼类群落的δ^(13)C和δ^(15)N值特征及营养结构进行分析。结果显示:恰甫... 为探究新疆高山冰雪融水水源水库鱼类群落营养结构特征,以新疆伊犁河上游恰甫其海和温泉水电站水库为研究对象,于2021年开展鱼类资源调查,并利用稳定同位素技术对鱼类群落的δ^(13)C和δ^(15)N值特征及营养结构进行分析。结果显示:恰甫其海共采集到12种鱼类,其δ^(13)C值范围为-28.24‰—-22.78‰,δ^(15)N值范围为7.49‰—12.37‰;温泉水电站水库共采集到^(13)种鱼类,其δ^(13)C值范围为-27.19‰—-22.26‰,δ^(15)N值范围为7.53‰—12.93‰。营养生态位分析显示,恰甫其海鱼类营养级范围为1.70—3.10,温泉水电站水库营养级范围为1.83—3.17,相较于内陆湖库,两座水库鱼类整体营养层级较低,且食物链较短。两座水库鱼类群落营养结构指标(氮值范围NR、碳值范围CR、生态位总空间TA、平均离心距离CD、平均最邻近距离MNND、最邻近距离标准差SDNND)显示,恰甫其海与温泉水电站水库的群落营养多样性程度接近,但温泉水电站水库生态系统稳定性更高。研究分析了两座水库的鱼类群落营养结构,丰富了新疆伊犁河流域山谷型水库鱼类群落基础数据,可为该地区未来湖库渔业科学管理和可持续发展提供基础资料。 展开更多
关键词 稳定同位素 鱼类营养结构 营养级 伊犁河上游 水库
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先进制造业集聚对新质生产力发展的影响——基于长江经济带的实证分析
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作者 周立新 何美萱 《工业技术经济》 北大核心 2026年第2期153-163,共11页
先进制造业集聚为培育新质生产力注入了核心动能。本文基于长江经济带2013~2023年59个地级及以上城市面板数据,实证分析先进制造业集聚对新质生产力发展的影响及机制。研究表明:先进制造业集聚能显著促进新质生产力发展,这一结果经一系... 先进制造业集聚为培育新质生产力注入了核心动能。本文基于长江经济带2013~2023年59个地级及以上城市面板数据,实证分析先进制造业集聚对新质生产力发展的影响及机制。研究表明:先进制造业集聚能显著促进新质生产力发展,这一结果经一系列稳健性检验后依然成立;同时,先进制造业集聚对新质生产力发展的促进作用在长江下游地区、高金融科技水平地区和高知识产权保护地区更明显;此外,先进制造业集聚通过促进产业结构高级化和提升创新活跃度驱动新质生产力发展。本文研究结果为长江经济带依托先进制造业集聚培育新质生产力提供理论支撑与实践路径。 展开更多
关键词 先进制造业集聚 产业结构高级化 创新活跃度 新质生产力 长江经济带 金融科技 知识产权保护 制造业集群
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金沙江下游梯级水库运行期设计洪水对比研究
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作者 钟斯睿 郭生练 +3 位作者 孙博凯 郭乐 梁志明 王何予 《人民长江》 北大核心 2026年第3期70-76,共7页
上游水库的联合调度已改变了金沙江下游梯级水库的天然来水来沙条件,原设计洪水和汛限水位无法适应新时期水旱灾害防治和水资源高效利用的需求。考虑上游水库群的调蓄影响,基于Vine Copula推求其最可能和最不利洪水地区组成,计算金沙江... 上游水库的联合调度已改变了金沙江下游梯级水库的天然来水来沙条件,原设计洪水和汛限水位无法适应新时期水旱灾害防治和水资源高效利用的需求。考虑上游水库群的调蓄影响,基于Vine Copula推求其最可能和最不利洪水地区组成,计算金沙江下游梯级水库运行期设计洪水,并与非一致性洪水频率分析方法进行对比,比选汛期控制水位方案。研究成果表明:①上游梯级水库调蓄作用显著削减了下游水库断面的洪水量级,根据最不利地区洪水组成结果,向家坝水库运行期1000 a一遇设计洪峰、3 d、7 d、15 d和30 d洪量相较天然设计成果削减约40.7%,37.8%,33.9%,24.4%和13.2%。②维持原防洪标准不变,乌东德、白鹤滩、溪洛渡和向家坝的汛期控制水位可抬升至958.56,794.67,568.75 m和373.42 m,6~9月共计可增发电量24.3亿kW·h。③最可能/最不利地区组成法计算结果与非一致性频率分析计算结果无显著差异,但能详细反映各级水库防洪调度过程。研究成果可为金沙江下游梯级水库运行调度提供理论和技术支撑,实现洪水资源化利用。 展开更多
关键词 梯级水库 设计洪水 洪水地区组成 汛控水位 金沙江下游
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三峡运行后长江中游砂卵石河段滩槽演变及通航水动力特征
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作者 杨云平 郑金海 +1 位作者 李明 朱玲玲 《水科学进展》 北大核心 2026年第1期147-160,共14页
流域梯级水库群联合运行后,枢纽下游河床冲刷已引起同流量-枯水位、水面比降和流速等适应性调整,这些要素变化叠加形成的“坡陡流急”会影响船舶通航安全。本文以长江中游砂卵石河段为对象,通过2002—2024年水文泥沙与河床地形等实测数... 流域梯级水库群联合运行后,枢纽下游河床冲刷已引起同流量-枯水位、水面比降和流速等适应性调整,这些要素变化叠加形成的“坡陡流急”会影响船舶通航安全。本文以长江中游砂卵石河段为对象,通过2002—2024年水文泥沙与河床地形等实测数据分析,解析河床冲淤强度与滩槽形态、同流量-枯水位、水面比降及最大流速等变化特征。研究表明:宜昌—大埠街河段枯水河槽、平滩河槽发生了累积性冲刷与深泓下切,洲滩面积先减小后逐渐稳定,深槽面积为增大态势;砂卵石河段同流量-枯水位为累积性下降态势,宜昌—枝城段枯水期水面比降较稳定,枝城—大埠街河段水面比降增大且发生天数增多使得“坡陡”现象增强;沙质河段河床冲刷及同流量-枯水位下降已引起砂卵石过渡段溯源冲刷作用增强,芦家河河段枯水期表层最大流速表征的“流急”特性增强;在无大型人类活动作用下,砂卵石河段的河床仍维持小幅冲刷,随着下游沙质河床段的持续强冲刷,引起砂卵石过渡段“坡陡流急”特性存在增强态势。 展开更多
关键词 滩槽形态 坡陡流急 水位变化 砂卵石河床 长江中游
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连云港市乌龙河生态水位确定及保障措施研究
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作者 徐欣宜 余鑫 +2 位作者 刘炜伟 周佳华 谢晓艳 《全面腐蚀控制》 2026年第1期326-328,共3页
为落实最严格水资源管理制度、推动河湖生态保护和高质量发展,本文以江苏省连云港市乌龙河为例,通过结合湿周法、最小生物空间法、排频法等综合分析确定了乌龙河控制断面的生态水位值为0.59m,并在此基础上构建起了“目标明确、责任清晰... 为落实最严格水资源管理制度、推动河湖生态保护和高质量发展,本文以江苏省连云港市乌龙河为例,通过结合湿周法、最小生物空间法、排频法等综合分析确定了乌龙河控制断面的生态水位值为0.59m,并在此基础上构建起了“目标明确、责任清晰、监测到位、调度有序”的生态水位保障体系,为平原河网地区生态水位确定技术方法增添了新鲜血液,所构建的保障体系也针对性强、可操作性强,能够为我国其他类似地区开展河湖生态水位管理及生态保护修复工作提供相应的技术参考和实践借鉴。 展开更多
关键词 生态水位 乌龙河 保障措施 湿周法 最小生物空间法
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河流-地下水交互带全氟和多氟烷基化合物迁移与滞留数值模拟研究
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作者 许诗滢 谢月清 +3 位作者 强郁城 孙媛媛 付融冰 吴吉春 《水文地质工程地质》 北大核心 2026年第2期223-234,共12页
全氟和多氟烷基化合物(perfluoroalkyl and polyfluoroalkyl substances,PFAS)作为新污染物,因其环境持久性与生物毒性对水环境构成严重威胁。而河流-地下水交互带中PFAS迁移与滞留特性尚不明确,需要揭示河水水位波动条件下PFAS在交互... 全氟和多氟烷基化合物(perfluoroalkyl and polyfluoroalkyl substances,PFAS)作为新污染物,因其环境持久性与生物毒性对水环境构成严重威胁。而河流-地下水交互带中PFAS迁移与滞留特性尚不明确,需要揭示河水水位波动条件下PFAS在交互带中的迁移与滞留机制,厘清PFAS迁移与滞留的关键控制参数。以全氟辛酸(perfluorooctanoic acid,PFOA)为典型污染物,首先基于土柱试验构建一维PFOA迁移模型,验证模型可靠性并反演吸附系数;继而构建二维河流-地下水断面模型,模拟PFOA在交互带中的运移过程及其对不同参数(波高、波长、吸附系数、渗透系数、入渗补给系数、孔隙度)的响应。研究表明:河水水位变化驱动的交互带蓄水效应显著延长了PFOA在交互带中的滞留时间,呈现“易进难出”的非对称迁移特征;与保守溶质相比,PFOA因吸附作用滞留更久;吸附系数、波高、波长和渗透系数是影响PFOA迁移与滞留的关键参数;吸附系数增大显著降低峰值浓度但同时大幅延长滞留时间,波高增大促使峰值升高与滞留时间延长,波长增加会延迟峰值到达时间并延长滞留时间,渗透系数提高可提升PFOA迁移速率并缩短滞留时间。相关成果可为季节性水位波动区域PFAS污染的风险评估与治理提供理论依据。 展开更多
关键词 全氟辛酸 河流 地下水 交互带 数值模拟 水位波动
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