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Two-thousand years of debates and practices of Yellow River training strategies 预览
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作者 Zhaoyin Wang Cheng Liu 《国际泥沙研究:英文版》 SCIE 2019年第1期73-83,共11页
Throughout the history of China,the Yellow River has been associated with flood disasters and changes in the course of its lower reaches because of sedimentation.From 602 B.C.to 1949 the river experienced 1593 levee b... Throughout the history of China,the Yellow River has been associated with flood disasters and changes in the course of its lower reaches because of sedimentation.From 602 B.C.to 1949 the river experienced 1593 levee bursts,flooding vast areas,and claiming millions of human lives.The river shifted its main course by avulsion 26 times with the apex around Zhengzhou,resulting in devastating calamities and numerous old channels.Training of the Yellow River has a history of more than 3000 yr.Levee construction has been the major strategy for flood control.Two extremely different strategies has been proposed and practiced in the past 2000 yr,i.e.the“wide river and depositing sediment”strategy and the“narrow river and scouring sediment”strategy.This paper analyzes the levee breaches and flood disasters in the past 2000 yr and compares the results of the two extremely different strategies.The“narrow river and scouring sediment”strategy has only short term effects on levee breach control and flood mitigation.The“wide river and depositing sediment”strategy can essentially mitigate flood disasters and reduce levee breaches for a long term period of time.The“wide river and depositing sediment”strategy has been used and no levee breach has occurred in the past 67 yr,which has been the only periods of more than 50 yr with no levee breaches in the history of the Yellow River since 700 A.D.Modern flood and sedimentation management methods have also been introduced,and the strategy of applying the“widen the river and enhance the levees”approach for the upper and lower reaches management is proposed. 展开更多
关键词 Yellow RIVER LEVEE breaches AVULSION Wide RIVER and depositing SEDIMENT STRATEGY Narrow RIVER and SCOURING SEDIMENT STRATEGY
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Hydrological Simulation Using TRMM and CHIRPS Precipitation Estimates in the Lower Lancang-Mekong River Basin 预览
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作者 LUO Xian WU Wenqi +2 位作者 HE Daming LI Yungang JI Xuan 《中国地理科学:英文版》 SCIE CSCD 2019年第1期13-25,共13页
Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall station... Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall stations are sparse and unevenly distributed, and the transboundary characteristic makes the collection of precipitation data more difficult, which has restricted hydrological processes simulation. In this study, daily precipitation data from four datasets(gauge observations, inverse distance weighted(IDW) data, Tropical Rainfall Measuring Mission(TRMM) estimates, and Climate Hazards Group InfraRed Precipitation with Stations(CHIRPS) estimates), were applied to drive the Soil and Water Assessment Tool(SWAT) model, and then their capability for hydrological simulation in the Lower Lancang-Mekong River Basin were examined. TRMM and CHIRPS data showed good performances on precipitation estimation in the Lower Lancang-Mekong River Basin, with the better performance for TRMM product. The Nash-Sutcliffe efficiency(NSE) values of gauge, IDW, TRMM, and CHIRPS simulations during the calibration period were 0.87, 0.86, 0.95, and 0.93 for monthly flow, respectively, and those for daily flow were 0.75, 0.77, 0.86, and 0.84, respectively. TRMM and CHIRPS data were superior to rain gauge and IDW data for driving the hydrological model, and TRMM data produced the best simulation performance. Satellite-based precipitation estimates could be suitable data sources when simulating hydrological processes for large data-poor or ungauged watersheds, especially in international river basins for which precipitation observations are difficult to collect. CHIRPS data provide long precipitation time series from 1981 to near present and thus could be used as an alternative precipitation input for hydrological simulation, especially for the period without TRMM data. For satellite-based precipitation products, the differences in the occurrence frequencies and amounts of precipitation with different intensities would affect simulation re 展开更多
关键词 hydrological simulation satellite-based PRECIPITATION ESTIMATES spatial distribution of PRECIPITATION international RIVER the LOWER Lancang-Mekong RIVER Basin
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Water Cooperation Priorities in the Lancang-Mekong River Basin Based on Cooperative Events Since the Mekong River Commission Establishment 预览
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作者 FENG Yan WANG Wenling +2 位作者 SUMAN Daniel YU Shiwei HE Daming 《中国地理科学:英文版》 SCIE CSCD 2019年第1期58-69,共12页
The Lancang-Mekong River has attracted much attention from researchers, but the cooperation on water issues in this river basin has been limited, even after the establishment of the Mekong River Commission(MRC). Coope... The Lancang-Mekong River has attracted much attention from researchers, but the cooperation on water issues in this river basin has been limited, even after the establishment of the Mekong River Commission(MRC). Cooperation on water resources has been determined as one of the key priority areas in the Lancang-Mekong Cooperation Mechanism, but there are no details of targets. In order to establish the priorities of water cooperation under the mechanism, we adopted nine categories to classify the objectives of 87 water cooperation events based on the ‘Lancang-Mekong Water Cooperative Events Database’ from 1995 to 2015. Based on the occurrence of cooperative events, cooperative objectives, cooperative scales, and approaches to cooperation, we conducted statistical, correlation, and text analyses. Our analyses indicated the following results: under the impact of economic conditions inside and outside the river basin, full cooperation appeared more difficult than bilateral and multilateral cooperation. Each of the partners adopted different preferences for cooperation targets. Cooperation with more definite objectives was easier to establish than cooperation with broader and more complex objectives. The potential objectives for water cooperation were navigation, hydropower, joint management, data sharing, flood control and water use. Because hydropower development is controversial, and because water cooperation is avoided by most existing regional cooperation mechanisms due to its complexity, we suggest the following priority areas for water cooperation in the Lancang-Mekong River Basin. 1) Navigation and flood control/drought relief are attractive objectives for all the riparian countries across the whole watershed. 2) Data sharing should be a priority for cooperation in the watershed due to its laying the foundation for the equitable and reasonable utilization of transboundary waters. 3) Hydropower is an objective best implemented mainly through bilateral cooperation, and on tributaries. 展开更多
关键词 water COOPERATION objective COOPERATIVE scale the Lancang-Mekong RIVER riparian country MEKONG RIVER COMMISSION
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ENERGIZING CAMBODIA'S ECONOMIC DEVELOPMENT 预览
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作者 Zhao Yipu 《中国东盟报道》 2019年第2期52-55,共4页
The winding Mekong River flows from north to south into Cambodia. In Stung Treng Province in the northeastern region of the country, a hundreds-of-kilometers-long tributary is known locally as the Sesan River.“Stung ... The winding Mekong River flows from north to south into Cambodia. In Stung Treng Province in the northeastern region of the country, a hundreds-of-kilometers-long tributary is known locally as the Sesan River.“Stung Treng Province enjoys an advantageous geographical position, so if Cambodia can develop and utilize such good resources, the province will develop impressively,” declared our driver as our car crossed the Sesan River along Highway No. 7. 展开更多
关键词 MEKONG RIVER Cambodia Sesan RIVER
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Hydrological and water cycle processes of inland river basins in the arid region of Northwest China
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作者 CHEN Yaning LI Baofu +2 位作者 FAN Yuting SUN Congjian FANG Gonghuan 《干旱区科学:英文版》 SCIE CSCD 2019年第2期161-179,共19页
The increasing shortage in water resources is a key factor affecting sustainable socio-economic development in the arid region of Northwest China(ARNC). Water shortages also affect the stability of the region’s oasis... The increasing shortage in water resources is a key factor affecting sustainable socio-economic development in the arid region of Northwest China(ARNC). Water shortages also affect the stability of the region’s oasis ecosystem. This paper summarizes the hydrological processes and water cycle of inland river basins in the ARNC, focusing on the following aspects: the spatial-temporal features of water resources(including air water vapor resources, runoff, and glacial meltwater) and their driving forces;the characteristics of streamflow composition in the inland river basins;the characteristics and main controlling factors of baseflow in the inland rivers;and anticipated future changes in hydrological processes and water resources. The results indicate that:(1) although the runoff in most inland rivers in the ARNC showed a significant increasing trend, both the glaciated area and glacial ice reserves have been reduced in the mountains;(2) snow melt and glacier melt are extremely important hydrological processes in the ARNC, especially in the Kunlun and Tianshan mountains;(3) baseflow in the inland rivers of the ARNC is the result of climate change and human activities, with the main driving factors being the reduction in forest area and the over-exploitation and utilization of groundwater in the river basins;and(4) the contradictions among water resources, ecology and economy will further increase in the future. The findings of this study might also help strengthen the ecological, economic and social sustainable development in the study region. 展开更多
关键词 water resources climate change RIVER RUNOFF BASEFLOW streamflow composition INLAND RIVER basin ARID region of Northwest China
Zhu Xianmo -- The Man Who Harnessed the Power of China’s Mother River 预览
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作者 DANG XIAOFEI 《今日中国:英文版》 2019年第5期48-49,共2页
THE Yellow River is the second longest river in China and called the cradle of Chinese civilization. With a drainage area totaling 750,000 square kilometers, it runs 5,464 kilometers through nine provinces and autonom... THE Yellow River is the second longest river in China and called the cradle of Chinese civilization. With a drainage area totaling 750,000 square kilometers, it runs 5,464 kilometers through nine provinces and autonomous regions before emptying into the Bohai Sea. 展开更多
关键词 China’s MOTHER RIVER YELLOW RIVER
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Quantitative analysis of planation surfaces of the upper Yangtze River in the Sichuan-Yunnan Region, Southwest China
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作者 Fenliang LIU Hongshan GAO +2 位作者 Baotian PAN Zongmeng LI Huai SU 《地球科学前沿:英文版》 SCIE CAS CSCD 2019年第1期55-74,共20页
Identification of the planation surfaces (PSs)is key for utilizing them as a reference in studying the long- term geomorphological evolution of the Upper Yangtze River Basin in the Sichuan-Yurman region,Southwest Chin... Identification of the planation surfaces (PSs)is key for utilizing them as a reference in studying the long- term geomorphological evolution of the Upper Yangtze River Basin in the Sichuan-Yurman region,Southwest China.Using a combined method of DEM-based fuzzy logic and topographic and fiver profiles analysis and based on a comprehensive analysis of four morphometfic parameters:slope,curvature,terrain raggedness index, and relative height,we established the relevant fuzzy membership functions,and then calculated the membership degree (MD)of the study area.Results show that patches with a MD>80% and an area>0.4 km^2 correspond well to the results of Google Earth and field investigation,representing the PS remnants.They consist of 1764 patches with an altitude,area,mean slope,and relief of mostly 2000-2500 m above sea level (asl),0-10 km^2,4°-9°,0-500 m,respectively,covering 9.2% of the study area's landscape,dipping to southeast,decreasing progressively from northwest to southeast in altitude,and with no clear relation between each patch's altitude and slope,or relief.All these results indicate that they are remnants of once regionally continuous PSs which were deformed by both the lower crust flow and the faults in upper crust,and dissected by the network of Upper Yangtze River.Additionally,topographic and river profiles analysis show that three PSs (PS1-PS3)well developed along the main valleys in the Yongren-Huili region, indicating several phases of uplift then planation during the Late Cenozoic era.Based on the incision amount deduced from projection of relict river profiles on PSs, together with erosion rates,breakup times of the PS 1,PS2,and PS3 were estimated to be 3.47 Ma,2.19 Ma,and 1.45 Ma,respectively,indicating appearance of modem Upper Yangtze River valley started between the Pliocene to early Pleistocene. 展开更多
关键词 planation surface fuzzy logic topographic ANALYSIS RIVER profile ANALYSIS Upper YANGTZE RIVER SOUTHWEST China
Evaluating Suitability of Multiple Precipitation Products for the Lancang River Basin 预览
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作者 TANG Xiongpeng ZHANG Jianyun +7 位作者 WANG Guoqing YANG Qinli YANG Yanqing GUAN Tiesheng LIU Cuishan JIN Junliang LIU Yanli BAO Zhenxin 《中国地理科学:英文版》 SCIE CSCD 2019年第1期37-57,共21页
Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sour... Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sources are suitable for all regions or perform the same way in hydrological modeling, so it is essential to test the suitability of precipitation products before applying them. In this study, five widely used global high-resolution precipitation products-Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources(APHRODITE), National Centers for Environmental Prediction Climate Forecast System Reanalysis(NCEP-CFSR), Climate Hazards Group InfraRed Precipitation with Station Data(CHIRPS), China Gauge-based Daily Precipitation Analysis developed by China Meteorological Administration(CMA) and Agricultural Model Intercomparison and Improvement Project based on the NASA Modern-Era Retrospective Analysis for Research and Applications(AgMERRA)-were evaluated using statistical methods and a hydrological approach for their suitability for the Lancang River Basin. The results indicated that APHRODITE, CMA, AgMERRA and CHIRPS were more accurate precipitation indicators than NCEP-CFSR in terms of the multiyear average and seasonal spatial distribution pattern, all of the CHIRPS, Ag MERRA and APHRODITE perform better than CMA and NCEP-CFSR at the small, medium and high precipitation intensities ranges in subbasin11 and sunbabsin46. All five products performed better in subbasin46(a low-altitude region) than in subbasin11(a high-altitude region) on the daily and monthly scales. In addition to NCEP-CFSR, the other four products all presented encouraging potential for streamflow simulation at daily(Yunjinghong) and monthly(Yunjinghong, Jiuzhou and Gajiu) scale. Hydrological simulations forced with APHRODITE were the best of the five for the Yunjinghong station in capturing daily and monthly measured streamflow. Except for NCEP-CFSR, all products were very good for hydrologic 展开更多
关键词 MULTIPLE PRECIPITATION PRODUCTS SUITABILITY evaluation the Lancang River BASIN
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Implementing of the JPWSPC method in RIV1H for unsteady flow modeling in general river networks 预览
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作者 Dejun Zhu Yongcan Chen 《国际泥沙研究:英文版》 SCIE 2019年第4期379-386,共8页
RIV1H is the stand-alone hydraulic program of CE-QUAL-RIV1, a longitudinal hydraulic and water quality model developed by U.S. Army Corps of Engineers Waterways Experiment Station. RIV1H solves the Saint-Venant equati... RIV1H is the stand-alone hydraulic program of CE-QUAL-RIV1, a longitudinal hydraulic and water quality model developed by U.S. Army Corps of Engineers Waterways Experiment Station. RIV1H solves the Saint-Venant equations using the widely accepted four-point implicit Preissmann scheme, and the resulting nonlinear equations are solved using the Newton-Raphson method. RIV1H is capable of simulating multiple branches, and in-stream hydraulic control structures. It treats tributary networks using a double sweep algorithm based on upstream ordering of the branches. It treats the control structures following a downstream solution order, which also is based on the upstream ordering of the branches. Since an upstream ordering cannot be achieved for looped networks, RIV1H is only applicable to non-looped tributary networks. In the current study, the junction-point water stage prediction and correction (JPWSPC) method is extended to take into account the control structures and the method is used to improve the RIV1H model, enabling it to be applied to both non-looped and looped networks with in-stream hydraulic control structures. The JPWSPC method makes the linear equation system for each segment complete while maintaining the banded property, thus the system can be independently and efficiently solved. It has the advantages to be efficient, robust, and very suitable for parallel computing. The improved RIV1H model was tested using two idealized networks and the results demonstrated the success of the improvement. 展开更多
关键词 RIV1H Numerical hydraulic model RIVER network Control structure Junction-point water STAGE prediction and CORRECTION
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基于河流生态系统健康的生态修复技术研究进展
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作者 刘欢 杨少荣 王小明 《水生态学杂志》 CSCD 北大核心 2019年第2期1-6,共6页
随着人类对河流大规模开发利用,河流生态系统遭受严重破坏。近年来,生态修复引起了社会广泛关注,也取得了显著的进步。本文从河流生态系统特性和所受胁迫出发,介绍了河流健康概念和评价方法,回顾了国内外河流生态修复相关研究发展历程,... 随着人类对河流大规模开发利用,河流生态系统遭受严重破坏。近年来,生态修复引起了社会广泛关注,也取得了显著的进步。本文从河流生态系统特性和所受胁迫出发,介绍了河流健康概念和评价方法,回顾了国内外河流生态修复相关研究发展历程,归纳了河流生态修复的理念,并以河流健康因素为基础,总结了水量、连通性、水质、水生生物4个方面的生态修复技术及其实践案例,最后根据当前研究的不足,提出了河流生态修复的3个研究方向,以期为未来的修复实践提供参考和指导。 展开更多
关键词 河流 生态系统 生态修复 修复技术
Distribution and Susceptibility Assessment of Collapses and Landslides in the Riparian Zone of the Xiaowan Reservoir 预览
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作者 ZHONG Ronghua HE Daming +3 位作者 HU Jinming DUAN Xingwu HUANG Jiangcheng CHENG Xupeng 《中国地理科学:英文版》 SCIE CSCD 2019年第1期70-85,共16页
The southwest alpine gorge region is the major state base of hydropower energy development in China and hence planned many cascading hydropower stations. After the reservoir impoundment, the intense water level fluctu... The southwest alpine gorge region is the major state base of hydropower energy development in China and hence planned many cascading hydropower stations. After the reservoir impoundment, the intense water level fluctuations under the interaction of cascade dams operating and the mountainous flooding, usually cause bank collapse, landslide and debris flow hazards. The Xiaowan reservoir(XWR), for example, as the ‘dragon head’ meg reservoir located in the middle mainstream of Lancang River, have resulted in a series of geohazards during its building and operating. In this study, we investigated the number and surface area of collapses and landslides(CLs) occurred in the water level fluctuations zone(WLFZ) of XWR using remote sensing images of Gaofen-1 and Google Earth;evaluated the CLs susceptibility using information value method. The results presented that the total WLFZ area of 87.03 km2 and 804 CLs masses with a total area of 1.98 km2 were identified in the riparian zone of XWR. CLs mainly occurred at an elevation of 1190–1240 m, and the CLs density increased with an increase in altitude. The WLFZ with a slope gradient of 25°– 45° is the main CLs distribution area that accounts for more than half of the total CLs area. The susceptibility assessment revealed that high and very high susceptibility zones are generally distributed along zones with an elevation of 1210–1240 m, a slope degree of 25°–45° and a slope aspect perpendicular to the direction of Lancang River. Furthermore, these susceptible zones are close in distance to the dam site and tend to be in the riparian zones with the formation lithology of Silurian strata. These results provide a valuable contribution to prevent and control geohazards in the XWR area. Moreover, this study offers a constructive sample of geohazards assessment in the riparian zone of large reservoirs throughout the mountains of southwest China. 展开更多
关键词 SUSCEPTIBILITY assessment collapses and LANDSLIDES water level FLUCTUATIONS Xiaowan RESERVOIR Lancang-Mekong River
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International Freight Forwarding Services Network in the Yangtze River Delta, 2005–2015: Patterns and Mechanisms 预览
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作者 LIANG Shuangbo CAO Youhui +3 位作者 WU Wei GAO Jinlong LIU Weichen ZHANG Weiyang 《中国地理科学:英文版》 SCIE CSCD 2019年第1期112-126,共15页
This study examined the spatio-temporal trajectories of the international freight forwarding service(IFFS) in the Yangtze River Delta(YRD) and explored the driving mechanisms of the service. Based on a bipartite netwo... This study examined the spatio-temporal trajectories of the international freight forwarding service(IFFS) in the Yangtze River Delta(YRD) and explored the driving mechanisms of the service. Based on a bipartite network projection from an IFFS firm-city data source, we mapped three IFFS networks in the YRD in 2005, 2010, and 2015. A range of statistical indicators were used to explore changes in the spatial patterns of the three networks. The underlying influence of marketization, globalization, decentralization, and integration was then explored. It was found that the connections between Shanghai and other nodal cities formed the backbones of these networks. The effects of a city’s administrative level and provincial administrative borders were generally obvious. We found several specific spatial patterns associated with IFFS. For example, the four non-administrative centers of Ningbo, Suzhou, Lianyungang, and Nantong were the most connected cities and played the role of gateway cities. Furthermore, remarkable regional equalities were found regarding a city’s IFFS network provision, with notable examples in the weakly connected areas of northern Jiangsu and southwestern Zhejiang. Finally, an analysis of the driving mechanisms demonstrated that IFFS network changes were highly sensitive to the influences of marketization and globalization, while regional integration played a lesser role in driving changes in IFFS networks. 展开更多
关键词 international FREIGHT FORWARDING service NETWORK pattern mechanism headquarters-branch method YANGTZE River DELTA
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河湖库塘清淤效益评估研究 预览
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作者 王开放 曾甄 《浙江水利科技》 2019年第1期6-9,共4页
为客观地科学评估河湖库塘清淤项目效果,从浙江省河湖库塘清淤现状出发,总结全省清淤、淤泥处理与处置的技术,分析清淤所带来的效益,采取替代法建立评价指标,提出一种定量分析河湖库塘清淤效益的评估方法,并举例论证。
关键词 河湖库塘 清淤效益 定量分析 评估方法
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Sedimentary Facies, Sequence Stratigraphic Patterns in Pre-Cenozoic Inland Compressional Basin: Example from Early Yanshanian Succession of Eastern Yihezhuang Salient, Jiyang Depression, Bohai Bay Basin, China
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作者 Guangzeng Song Hua Wang +2 位作者 Meng Xu Jinda Xu Guoqing Sang 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第1期194-205,共12页
To improve the success rate of locating hydrocarbon reservoirs in pre-Cenozoic inland compressional basins, taking the Early Yanshanian succession of eastern Yihezhuang salient as an example, this paper studied the se... To improve the success rate of locating hydrocarbon reservoirs in pre-Cenozoic inland compressional basins, taking the Early Yanshanian succession of eastern Yihezhuang salient as an example, this paper studied the sedimentary facies and sequence stratigraphic patterns. First, through seismic profiles, well logs, cores and outcrops, the sequence framework was established and internal sedimentary facies were identified. Further, according to analysis of single-wells and connecting-wells, the vertical evolution and horizontal distribution of sedimentation inside the sequence frameworks were discussed. The following results were acquired:(1) meandering river characterized by dual structures superposing each other was developed, and the dual structures can be further divided into three kinds;(2) the entire Early Yanshanian succession was interpreted as one first-order sequence, composed of three third-order sequences, including SQ-Fz1, SQ-Fz2 and SQ-St from bottom to top. Each third-order sequence can be further divided into three system tracts;(3) in different system tracts, different types of dual structures developed separately, and sedimentary bodies showed different horizontal distribution scales and vertical superposition patterns. Finally, the model of sequence stratigraphic patterns was established. This study enhanced the use of sequence stratigraphy to inland tectonically active basins, and would be helpful to predict reservoirs in pre-Cenozoic residual basins. 展开更多
关键词 Early YANSHANIAN SUCCESSION SEQUENCE STRATIGRAPHIC PATTERNS INLAND compressional basin meandering river dual structure
Source attribution for mercury deposition with an updated atmospheric mercury emission inventory in the Pearl River Delta Region, China
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作者 Jiajun Liu Long Wang +7 位作者 Yun Zhu Che-Jen Lin Carey Jang Shuxiao Wang Jia Xing Bin Yu Hui Xu Yuzhou Pan 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期39-52,共14页
We used CMAQ-Hg to simulate mercury pollution and identify main sources in the Pearl River Delta (PR.D) with updated local emission inventory and latest regional and global emissions. The total anthropogenic mercury e... We used CMAQ-Hg to simulate mercury pollution and identify main sources in the Pearl River Delta (PR.D) with updated local emission inventory and latest regional and global emissions. The total anthropogenic mercury emissions in the PRD for 2014 were 11,939.6 kg. Power plants and industrial boilers were dominant sectors, responsible for 29.4 and 22.7%. We first compared model predictions and observations and the results showed a good performance. Then five scenarios with power plants (PP), municipal solid waste incineration (MSWI), industrial point sources (IP), natural sources (NAT), and boundary conditions (BCs) zeroed out separately were simulated and compared with the base case. BCs was responsible for over 30% of annual average mercury concentration and total deposition while NAT contributed around 15%. Among the anthropogenic sources, IP (22.9%) was dominant with a contribution over 20.0% and PP (18.9%) and MSWI (11.2%) ranked second and third. Results also showed that power plants were the most important emission sources in the central PRD, where the ultra-low emission for thermal power units need to be strengthened. In the northern and western PRD, cement and metal productions were priorities for mercury control. The fast growth of municipal solid waste incineration were also a key factor in the core areas. In addition, a coordinated regional mercury emission control was important for effectively controlling pollution. In the future, mercury emissions will decrease as control measures are strengthened, more attention should be paid to mercury deposition around the large point sources as high levels of pollution are observed. 展开更多
关键词 Emission INVENTORY MERCURY deposition PEARL River Delta (PRD) Source ATTRIBUTION Control strategy
整体提高苏州市古城区河道淤泥固化泥饼含固率的研究与实践 预览
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作者 魏本精 严研 季化猛 《水资源开发与管理》 2019年第1期68-72,78共6页
为提高苏州市古城区河道淤泥固化泥饼含固率的整体水平,确保淤泥固化质量和工期,QC小组针对淤泥固化泥饼含水率高、含固率低的问题进行了原因分析和要因确认,并据此提出了相应的解决对策。对策实施后,苏州市古城区河道淤泥固化的合格率... 为提高苏州市古城区河道淤泥固化泥饼含固率的整体水平,确保淤泥固化质量和工期,QC小组针对淤泥固化泥饼含水率高、含固率低的问题进行了原因分析和要因确认,并据此提出了相应的解决对策。对策实施后,苏州市古城区河道淤泥固化的合格率大幅度提高,有利于下一步进行固化泥饼的处置和利用。 展开更多
关键词 河道 淤泥 固化 含固率
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Different Flooding Behaviors Due to Varied Urbanization Levels within River Basin: A Case Study from the Xiang River Basin,China
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作者 Juan Du Linlin Cheng +2 位作者 Qiang Zhang Yumeng Yang Wei Xu 《国际灾害风险科学学报:英文版》 CSCD 2019年第1期89-102,共14页
Booming urbanization due to a fast-growing population results in more impervious areas, less infiltration,and hence greater flood peak and runoff. Clear understanding of flood responses in regions with different level... Booming urbanization due to a fast-growing population results in more impervious areas, less infiltration,and hence greater flood peak and runoff. Clear understanding of flood responses in regions with different levels and expansions of urbanization is of great importance for regional urban planning. In this study, comparison of flooding responses to urbanization processes in terms of flood peak and runoff volume in the upper, middle,and lower Xiang River Basin(XRB), China, was carried out using the Hydrologic Engineering Center-Hydrologic Modeling System(HEC-HMS) model. From 2005 to 2015, urbanization level and intensity were higher in the lower XRB compared to the upper and middle XRB, and the overall expansion rate of urban areas was 112.8%.Modeling results by the HEC-HMS model indicate elevated flood peak discharges and volumes due to fast urbanization in the XRB from the 1980 s to 2015. This rapid increase is particularly the case in the lower XRB. The study also revealed different hydrological responses of flood regimes—urbanization tends to have larger impacts on peak flood flow rather than on flood volume in the lowerXRB, which further corroborated urbanization-induced intensifying flood processes in terms of peak flood flow.Urbanization has increasing impacts on flood volume from the upper to the lower XRB, which can be attributed to accumulated runoff down the river system. This study provides a reference for basin-wide land use and urban planning as well as flood hazard mitigation. 展开更多
关键词 FLOOD volume FLOODING processes HECHMS PEAK FLOOD flow URBANIZATION level Xiang River Basin China
雅鲁藏布江河水中CH4和N2O气体浓度及释放特征
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作者 叶润成 吴起鑫 +3 位作者 赵志琦 胡健 崔丽峰 丁虎 《生态学杂志》 CAS CSCD 北大核心 2019年第3期791-798,共8页
河流向大气释放大量温室气体,是陆地生态系统物质循环和能量流动的重要环节。山地河流是温室气体排放的热点区域,但迄今山地河流CH4和N2O释放方面的研究较少。为探究高原中大型河流CH4和N2O浓度的时空分布特征及其影响因素,对雅鲁藏布江... 河流向大气释放大量温室气体,是陆地生态系统物质循环和能量流动的重要环节。山地河流是温室气体排放的热点区域,但迄今山地河流CH4和N2O释放方面的研究较少。为探究高原中大型河流CH4和N2O浓度的时空分布特征及其影响因素,对雅鲁藏布江(雅江)干流和主要支流河水中CH4和N2O气体进行了季节性采样分析。结果表明,雅江河水中CH4含量为2.3~864.9 nmol·L-1,N2O含量为8.2~23.7 nmol·L-1,枯水期CH4含量和丰水期无显著差异(P=0.112),但枯水期N2O含量显著高于丰水期(P=0.017),流量和水温可能分别是影响CH4和N2O变化的主要因子。雅江河水CH4和N2O的释放速率分别为4.3~11.1 mg C·m-2·d-1和0.16~0.37 mg N·m-2·d-1,排放量分别为1.88~4.59Gg C·a-1和0.07~0.16 Gg N·a-1,分别约占全球河流CH4和N2O释放量的1.25‰~3.06‰和2.17‰~4.96‰。山地河流CH4和N2O的排放需要引起重视,全球河流温室气体释放可能需要进行重新评估。 展开更多
关键词 河流 甲烷(CH4) 氧化亚氮(N2O) 气体通量 影响因素
No Time to Waste
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作者 Xia Yuanyuan 《中国与非洲:英文版》 2019年第5期28-29,共2页
Located some 80 km from Ethiopia's capital Addis Ababa, the Modjo River is an important water source for the country s many inhabitants. Para doxically, it is also one of the most polluted rivers in the country. A... Located some 80 km from Ethiopia's capital Addis Ababa, the Modjo River is an important water source for the country s many inhabitants. Para doxically, it is also one of the most polluted rivers in the country. A major pollutant in the river is industiial waste, containing high levels of chromium emanating from leather manufacturing companies found in the ai ea. 展开更多
关键词 CAPITAL RIVER
河流水动力条件对大型底栖动物分布影响研究进展 预览
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作者 陈含墨 渠晓东 王芳 《环境科学研究》 EI CAS CSCD 北大核心 2019年第5期758-765,共8页
大型底栖无脊椎动物(简称"底栖动物")是河流生态系统重要的生物类群,其组成与分布受河流水动力条件影响显著.对世界范围内不同气候带的7条大型河流的研究发现,底栖动物在河流纵向上展现出了明显的分布特征:①山区树线以上,粗... 大型底栖无脊椎动物(简称"底栖动物")是河流生态系统重要的生物类群,其组成与分布受河流水动力条件影响显著.对世界范围内不同气候带的7条大型河流的研究发现,底栖动物在河流纵向上展现出了明显的分布特征:①山区树线以上,粗颗粒有机物有限,直接收集者占绝对优势,其中流速大的河段以适应流水的摇蚊幼虫为主,流速低的河段以寡毛类为主.②树线以下的上游河段,充足的凋落物进入河流,流速大的河段以抗冲刷能力强的水生昆虫(如蜉蝣目)为主,流速低的河段以寡毛类和摇蚊幼虫为主.③中下游河段以及河口地区,河流比降小、水深大、流速小、底质较细,受一定程度的人类活动影响,寡毛类、摇蚊幼虫和软体动物等较为常见,其中寡毛类和软体动物主要栖息在淤泥底质中,摇蚊幼虫在沙质河中更为常见.底栖动物的物种数量及组成与底质的稳定性、河流含沙量、降水量等因素相关.水动力条件中的底质、含沙量及流速对底栖动物的影响最为显著:①底栖动物物种数随着底质粒径和稳定性的降低而减少,在卵石底质中达到最大值.②含沙量增加导致底栖动物的物种数和密度显著下降.③汛期水动力条件的改变直接导致底栖动物密度和优势种变化,汛期过后则优势种恢复,密度达到年内最大值.研究推测气候通过影响底栖动物食物网来影响其密度,而不是种类.建议今后增强气候变化对底栖动物食物网及密度综合影响的研究. 展开更多
关键词 河流 底栖动物 水动力 底质
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