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Changjiang River sediment delivering into the sea in response to water storage of Sanxia Reservoir in 2003 被引量:6
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作者 CHU Zhongxin ZHAI Shikui CHEN Xiufa 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第2期71-79,共9页
The Sanxia Reservoir on the Changjiang River stored water from 1 to 10 June and from 25 October to 5 November in 2003, elevating the water level to 135 and 139 m above mean sea level at the dam, respectively. A monthl... The Sanxia Reservoir on the Changjiang River stored water from 1 to 10 June and from 25 October to 5 November in 2003, elevating the water level to 135 and 139 m above mean sea level at the dam, respectively. A monthly dataset of water discharge, suspended sediment concentration (SSC) and sediment load of the Changjiang River from 1953 to 2003 measured at the Datong Hydrological Gauging Station of the downstreammost Changjiang River was mainly used to examine the Changjiang River sediment delivering into the sea in 2003 in response to the Sanxia Reservoir water storages in the same year. The results show that (1) compared with those in 2002, 2001, and the multi-yearly (1953-2000) average, both annual SSC and sediment load at Datong in 2003 were markedly reduced, and they were even smaller than the multi-yearly (1953-2000) minimum, although the annual runoff in 2003 did not change largely; and (2) compared with those in the corresponding months in 2002, 2001 and the multi-monthly average from 1953 to 2000, monthly SSC and sediment load at Datong both in June and November of 2003 were also markedly reduced, and those in June 2003 were even smaller than the multi-monthly minimum from 1953 to 2000. These may indicate that sediment sedimentation in the Sanxia Reservoir resulting from the Sanxia Reservoir water storage should be the main cause of the decreased annual and monthly SSC and sediment load of the Changjiang River into the sea in 2003. Besides, it seems that the Sanxia Reservoir water storage in the early June (flood season) of 2003 had more impacts on the decreased monthly SSC into the sea than that in the late October and early November (approximately non-flood season) of 2003. 展开更多
关键词 changjiang (Yangtze) river Sanxia Reservoir water storage SEDIMENT
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Water discharge changes of the Changjiang River downstream Datong during dry season 被引量:2
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作者 ZHANG Erfeng,CHEN Xiqing,WANG Xiaoli(State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China) 《Journal of Geographical Sciences》 SCIE CSCD 2003年第3期355-362,共8页
Based on hydrometric data and extensive investigations on water-extracting projects, this paper presents a preliminary study on water discharge changes between Datong and Xuliujing during dry season. The... Based on hydrometric data and extensive investigations on water-extracting projects, this paper presents a preliminary study on water discharge changes between Datong and Xuliujing during dry season. The natural hydrological processes and human factors that influence the water discharge are analyzed with the help of GIS method. The investigations indicate that the water-extracting projects downstream from Datong to Xuliujing had amounted to 64 in number by the end of 2000, with a water-extracting capacity up to 4,626 m 3 /s averaged in a tidal cycle. The water extraction from the Changjiang River has become the most important factor influencing the water discharge downstream Datong during dry season. The potential magnitude in water discharge changes are estimated based on historical records of water extraction and a water balance model. The computational results were calibrated with the actual data. The future trend in changes of water discharge into the sea during dry season was discussed by taking into consideration of newly built hydro-engineering projects. The water extraction downstream Datong in dry season before 2000 had a great influence on discharges into the sea in the extremely dry year like 1978-1979. It produced a net decrease of more than 490 m 3 /s in monthly mean discharges from the Changjiang into the sea. It is expected that the water extraction will continually increase in the coming decades, especially in dry years, when the net decrease in monthly mean water discharge will increase to more than 1000 m 3 /s and will give a far-reaching effect on the changes of water discharge from the Changjiang into the sea. 展开更多
关键词 the changjiang river dry season water discharge into the sea human impacts
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Water discharge variability of Changjiang(Yangtze) and Huanghe(Yellow) Rivers and its response to climatic changes 被引量:2
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作者 张喜林 范德江 +1 位作者 王厚杰 杨作升 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第6期1392-1405,共14页
Influences of large-scale climatic phenomena,such as the El Nino/La Nina-Southern Oscillation(ENSO) and the Pacific Decadal Oscillation(PDO),on the temporal variations of the annual water discharge at the Lijin statio... Influences of large-scale climatic phenomena,such as the El Nino/La Nina-Southern Oscillation(ENSO) and the Pacific Decadal Oscillation(PDO),on the temporal variations of the annual water discharge at the Lijin station in the Huanghe(Yellow) River and at the Datong station in the Changjiang(Yangtze)River were examined.Using the empirical mode decomposition-maximum entropy spectral analysis(EMDMES A) method,the 2- to 3-year,8- to 14-year,and 23-year cyclical variations of the annual water discharge at the two stations were discovered.Based on the analysis results,the hydrological time series on the interannual to interdecadal scales were constructed.The results indicate that from 1950 to 2011,a significant downward trend occurred in the natural annual water discharge in Huanghe River.However,the changes in water discharge in Changjiang River basin exhibited a slightly upward trend.It indicated that the changes in the river discharge in the Huanghe basin were driven primarily by precipitation.Other factors,such as the precipitation over the Changjiang River tributaries,ice melt and evaporation contributed much more to the increase in the Changjiang River basin.Especially,the impacts of the inter-annual and inter-decadal climate oscillations such as ENSO and PDO could change the long-term patterns of precipitation over the basins of the two major rivers.Generally,low amounts of basin-wide precipitation on interannual to interdecadal scales over the two rivers corresponded to most of the warm ENSO events and the warm phases of the PDO,and vice versa.The positive phases of the PDO and ENSO could lead to reduced precipitation and consequently affect the long-term scale water discharges at the two rivers. 展开更多
关键词 长江流域 污水排放 黄河流域 气候变化 流量变化 ENSO事件 太平洋十年涛动 流域降水
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Source apportionment of river water pollution in a typical agricultural city of Anhui Province, eastern China using multivariate statistical techniques with APCS– MLR 被引量:1
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作者 Kai Chen Qi-meng Liu +2 位作者 Wei-hua Peng Yu Liu Zi-tao Wang 《Water Science and Engineering》 EI CAS CSCD 2023年第2期165-174,共10页
The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential po... The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential pollution sources. In this study, 99 water samples were collected from a river in a typical agricultural city of Anhui Province in eastern China, and these samples were analyzed in terms of pH, electrical conductivity, and the concentrations of F-, Cl-, SO42-, Na+, K+, Mg2+, Ca2+, As, Cr, Cu, Zn, and Pb. Cluster analysis, co-occurrence network analysis, and principal component analysis/factor analysis were conducted to qualitatively identify the potential sources of river water pollution in the study area. An absolute principal component score-multiple linear regression receptor model was used to quantitatively evaluate the contribution of each source to water quality parameters. The results showed that all observed water quality indices met the quality criteria specified in the Chinese drinking water standards, except for pH, ρ(F-), ρ(SO42-), and ρ(As). The heat map showed that the frequent recharge of pollutants from the tributaries during the wet season was the main reason for the deterioration of water quality. Five sources of river water pollution were identified, and their contribution ratios in a descending order were as follows: the geogenic process (24%) > agricultural activities (21%) > poultry farming sources (17%) > domestic pollution (9%) > transportation pollution (5%). Therefore, controlling pollution from agricultural activities, strengthening the regulation of livestock farming, and improving the sewage network are the recommended strategies for improving the quality of surface water resources in this area. 展开更多
关键词 Surface water water quality Source apportionment APCS-MLR model huaihe river basin
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MIXING OF SALT WATER AND FRESH WATER IN THE CHANGJIANG RIVER ESTUARY AND ITS EFFECTS ON SUSPENDED SEDIMENT 被引量:5
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作者 沈焕庭 张重乐 《Chinese Geographical Science》 SCIE CSCD 1992年第4期83-91,共9页
Using field hydrological data, the relationship between the mixing of salt water and fresh water and the tidal range/ high tidal level in the Changjiang (Yangtze) River estuary is discussed, and the transporting and c... Using field hydrological data, the relationship between the mixing of salt water and fresh water and the tidal range/ high tidal level in the Changjiang (Yangtze) River estuary is discussed, and the transporting and concentrating of suspended sediment in the estuary were also analysed in respect to the circulation, flocculation and stratified interface resulting from mixing.The calculation results by two-dimentional box model have confirmed the effects of the circulation on the concentrating of suspended sediment in the estuary. The conclusions derived from this work have deepened the understanding on the mixing in the Changjiang River estuary and are of significance in bo’th theory and practice. 展开更多
关键词 MIXING of salt water and FRESH water suspended sediment circulation FLOCCULATION the changjiang river ESTUARY
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A numerical study of summertime expansion pattern of Changjiang (Yangtze) River diluted water 被引量:6
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作者 SHAN Feng QIAO Fangli XIA Changshui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第3期11-16,共6页
Observations show that during summer especially in August, the northward expansion of the Changjiang(Yangtze) River diluted water (CRDW) is blocked in the vicinity of the Changjiang Estuary. To explain this phenom... Observations show that during summer especially in August, the northward expansion of the Changjiang(Yangtze) River diluted water (CRDW) is blocked in the vicinity of the Changjiang Estuary. To explain this phenomenon, Princeton ocean model (POM) is applied to simulate the summertime expansion pattern of CRDW. Numerical experiments show that to the north of the Changjiang Estuary, a tide-induced temperature front of a cold water centered at (34°N, I22.5°E) plays the key role in determining the expansion pattern of CRDW. This front splits the CRDW into two parts: the main part expands northeastward, and the other small part expands northwestward off the coast of Jiangsu Province, China. 展开更多
关键词 changjiang river diluted water Princeton ocean model expansion dynamics
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AN ANALYSIS OF THREE ELEMENTS OF WATER BALANCE IN THE CHANGJIANG RIVER BASIN 被引量:1
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作者 杨远东 《Chinese Geographical Science》 SCIE CSCD 1991年第3期3-17,共15页
The general trend of three elements (precipitation, runoff and evaporation) of the water balance of the Changjiang River Basin is discussed from the regional distribution of the mean annual values of view, i.e. isogra... The general trend of three elements (precipitation, runoff and evaporation) of the water balance of the Changjiang River Basin is discussed from the regional distribution of the mean annual values of view, i.e. isogram. The distribution of precipitation is non-uniform. The distribution of runoff mainly supplied from precipitation is more uniform than that of precipitation. The distribution of the evaporation from land is much more uniform than that of precipitation and runoff. Time distribution of these three elements shows the characteristics of comparatively distinct yearly variation and few variation between years. The relationship between precipitation and runoff, and between precipitation and evaporation in the humid region in the Changjiang River is analyzed. The slopes of their straight line correlation are nearly equal. The internal relationship between variables should be paid attention to, otherwise, a pseudo correlation may be resulted in. The paper provides the method of quantitative 展开更多
关键词 precipitation RUNOFF EVAPORATION the changjiang river BASIN water BALANCE
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IMPACTS OF FUTURE SEA LEVEL RISE ON SALT WATER INTRUSION IN THE CHANGJIANG RIVER ESTUARY 被引量:1
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1992年第1期31-42,共12页
Sea level rise could increase the salinity of an estuary by altering the balance between fresh water and salt water. The implications of sea level rise for increasing salinity have been examined in the Changjiang (Yan... Sea level rise could increase the salinity of an estuary by altering the balance between fresh water and salt water. The implications of sea level rise for increasing salinity have been examined in the Changjiang (Yangtze) River estuary. By correlative analysis of chlorinity, discharge and tidal level and calculation of two-dimensional chlorinity, distribution of the Changjiang River estuary, the changes of the intensity and lasting hours of salt water intrusion at Wusong Station and the changes of chlorinity distribution in the South Branch of the Changjiang River estuary have been estimated when future sea level rises 50-100 cm. The intensity of salt water intrusion in the future will be far more serious than current trend. 展开更多
关键词 sea level RISE SALT water INTRUSION chlonnity the changjiang river ESTUARY
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THE CHANGE OF THE GENERAL FORM AND THE TRANSPORT OF THE WATER, LOAD AND SALT ABOUT THE NORTH-BRANCH OF THE CHANGJIANG RIVER MOUTH 被引量:1
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作者 陈宝冲 《Chinese Geographical Science》 SCIE CSCD 1994年第3期242-251,共10页
陈宝冲THECHANGEOFTHEGENERALFORMANDTHETRANSPORTOFTHEWATER,LOADANDSALTABOUTTHENORTH-BRANCHOFTHECHANGJIANGRIVERMOU... 陈宝冲THECHANGEOFTHEGENERALFORMANDTHETRANSPORTOFTHEWATER,LOADANDSALTABOUTTHENORTH-BRANCHOFTHECHANGJIANGRIVERMOUTH¥ChenBaochong(N... 展开更多
关键词 north-branch of the changjiang river MOUTH change of river form transport of water load and SALT
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Turning mechanism problems of the Changjiang River diluted water 被引量:1
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作者 Zhao Baoren Institute of Oceanology, Academia Sinica, Qingdao 266071, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第3期317-329,共13页
Some main ideas about the turning of the Changjiang River diluted water (CDW) and their deficiencies are reviewed in this paper. According to a large number of observation data it is pointed out that the turning pheno... Some main ideas about the turning of the Changjiang River diluted water (CDW) and their deficiencies are reviewed in this paper. According to a large number of observation data it is pointed out that the turning phenomena of the CDW are related not only to the discharge of the Changjiang River but also to the sea surface slope and wind stress curl in the southeast coast of China. Exsistence of the sea surface slope reflects essentially the effect of the Taiwan Warm Currc (TWC) on the turning of the CDW. 展开更多
关键词 In area WANG Turning mechanism problems of the changjiang river diluted water
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An Observational Analysis of the Relationship Between Wind and the Expansion of the Changjiang River Diluted Water during Summer 被引量:2
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作者 LIU Bao-Chao FENG Li-Cheng 《Atmospheric and Oceanic Science Letters》 2012年第5期384-388,共5页
This paper presents an analysis of the impact of wind on the transport of the Changjiang River Diluted Water (CRDW) in August by using the salinity data collected on two zonal sections near Cheju-do. Based on the clim... This paper presents an analysis of the impact of wind on the transport of the Changjiang River Diluted Water (CRDW) in August by using the salinity data collected on two zonal sections near Cheju-do. Based on the climatological mean conditions and four extreme events, the analysis indicates that wind-induced Ekman transport plays an important role in the extension of the CRDW. The strong northeastward Ekman transport induced by southeasterly wind in 1996, 2003, 2004, and 2006 pushes the core of the CRDW to the sea adjacent to Cheju-do. A comparison of the wind variation before observation among these four extreme events indicates that the expansion pattern of the CRDW is primarily changed by synoptic variation with timescales of days to weeks, such as during a typhoon. The weak eastward extension of the CRDW in 2004, accompanied with a relatively strong southerly wind, implies that the oceanographic state (e.g., the depth of halocline) may strongly affect the impact of wind on the extension of the CRDW. 展开更多
关键词 水稀释 夏季风 长江 极端事件 长三角地区 数据收集 东南风 盐跃层
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SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER
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作者 XIA Xing-hui1, CHEN Jing-sheng2, CAI Xu-yi3(1. Institute of Environmental Sciences, Beijing Normal University / State Key Joint Laboratory of EnvironmentalSimulation and Pollution Control, Beijing 100875, P. R. China 2. Department of U 《Chinese Geographical Science》 SCIE CSCD 2001年第4期29-34,共6页
ABSTRACT: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang( Yangtze) River, etc. The fluctuations of Ca2 +, Mg2+ ... ABSTRACT: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang( Yangtze) River, etc. The fluctuations of Ca2 +, Mg2+ and HCO3-concentrations in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation(QBO). Na + Cl- SO2-4 have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn’t exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river discharge fluctuation accounts for 43. 9% , 45.1%, 54.3%, 33.9%, 30.3% and 42. 7% of the variance of Ca2 +, Mg2+ HC03-, Na+ Cl-, SO2-4, respectively, at Wuhan from 1962 to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data. 展开更多
关键词 MAJOR IONS spectrum characteristic of water QUALITY water QUALITY change the changjiang river
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FORECAST OF IMPACTS OF SEA-LEVEL RISE ON THELOW COLONIZED ISLANDS AND THEIR SURROUNDING WATERS IN THE CHANGJIANG RIVER MOUTH
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作者 YANG Shi-lun ZHAO Qing-ying +1 位作者 XIE Wen-hui WANG Xing-fang(State Key Laboratory of Estuarine & Coastal Research, East China Normal University, Shanghai 200062, P R. China) 《Chinese Geographical Science》 SCIE CSCD 2000年第2期113-118,共6页
As a worldwide authoritative, IPCC forecasted in 1990 that the world- s sea level would most probably rise by 0. 66 m by the end of the 21 st century. Combined with the local depression caused by the sink of the earth... As a worldwide authoritative, IPCC forecasted in 1990 that the world- s sea level would most probably rise by 0. 66 m by the end of the 21 st century. Combined with the local depression caused by the sink of the earth’s crust and the human activity, the relative sea level in the Chanaiiang River mouth will rise by about 1. 0 m during the same peried. Based on this figure, the article forecasted the impacts of sea-level rise on the safety coefficient of coastal structures and civil facilities, loss of wetlands, flood hazard as well as water intrusion. The results show that: 1 ) 40% as large as the present engil1eering mass should be added to the coastal structures in order to maintain the safety coefficient; 2 ) a dynamic loss of 60 km2 of wetlands, as much as 15% of the present total area, would be caused; 3) to hinder the increase inflood hazard dy11amic capacity to drain water must increase by at least 34 times as large as the present; 4) to maintain the present navigation conditions, about 100 million yuan (RMB) is needed to reconstruct over 30(X) bridges and 30 sluices;and 5 ) the disastrous salt water intrusion caused by the sea-level rise could be encountered by the increase in water discharge from the Three Gorge Reservoir in the dry season. 展开更多
关键词 SEA-LEVEL rise flood hazard loss of wetland salt water INTRUSION changjiang river MOUTH
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Observational characteristics and dynamic mechanism of low-salinity water lens for the offshore detachment of the Changjiang River diluted water in August 2006
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作者 Zhenyu Liu Wenjing Zhang +1 位作者 Xuejun Xiong Shouxian Zhu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第3期34-45,共12页
The Changjiang River diluted water(CDW)spreads into the East China Sea(ECS)primarily in a plume pattern,although in some years,low-salinity water lenses(LSWLs)detach from the main body of the CDW.In-situ observations ... The Changjiang River diluted water(CDW)spreads into the East China Sea(ECS)primarily in a plume pattern,although in some years,low-salinity water lenses(LSWLs)detach from the main body of the CDW.In-situ observations indicate that in August 2006,a LSWL detached from the main body of the CDW near the river mouth.In this paper,the effects of winds,tides,baroclinity and upwelling on LSWLs are explored with a threedimensional model.The results show that:(1)winds play a crucial role in these detachment events because windinduced northerly Eulerian residual currents impose an uneven force on the CDW and cut it off,thus forming a LSWL;(2)upwelling carries high-salinity water from the lower layer to the upper layer,truncating the low-salinity water tongue vertically,which is conducive to the detachment and maintenance of LSWLs;and(3)upwelling during the evolution of a LSWL is caused by the combined effects of winds and tides.The influences of windinduced upwelling are mainly near the shore,whereas the upwelling along the 30 m isobath is predominantly affected by tides,with the effect increasing from neap tide to spring tide. 展开更多
关键词 changjiang river diluted water low-salinity water lens numerical simulation observational characteristics dynamic mechanism upwelling
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Degeneration and countermeasures of water resources system of the Changjiang River Delta
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作者 Dong WANG Yunliang SHI +1 位作者 Lachun WANG Jichun WU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期169-169,共1页
关键词 长江三角洲 水资源 退化 排水
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Study on Water Pollution Control of Huaihe River and Countermeasures
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作者 Ni Tianhua Sun Ping Xu Jiangang Diao Weiping 《China Standardization》 2010年第6期8-16,共9页
Huaihe 河是有一张大人口的中国的三条主要的河之一并且开发经济。由 1970 年代, Huaihe 河的水质量每天并且非常正在败坏水质量的 100 个严肃的污染事故发生了并且沿着河并且可怕地在居民的生产,生活和健康引起了无法估计的损失损坏... Huaihe 河是有一张大人口的中国的三条主要的河之一并且开发经济。由 1970 年代, Huaihe 河的水质量每天并且非常正在败坏水质量的 100 个严肃的污染事故发生了并且沿着河并且可怕地在居民的生产,生活和健康引起了无法估计的损失损坏了河的生态的系统。通过为超过 10 年的连续大规模处理, Huaihe 河里的水质量的恶化基本上被禁止了。不过, Huaihe 河里的水污染是总体上,为许多原因仍然很严肃包括特殊气候的条件,为河的水资源,过时的工业结构和腐烂的管理系统的可怕的缺乏,等等。这篇散文深深地分析 Huaihe 河的水污染是“长期”的并且提出为怎么连续地改进河的水质量的相应反措施的原因。最后,就算每项措施顺利被实现并且严格地,清洗实际上做 Huaihe 河的水并且逐渐地恢复它的正常生态、环境的功能,这篇散文主张它仍然花 30-50 年或甚至一个更长的时期。 展开更多
关键词 淮河流域 流域水质 污染控制对策 生态系统 水质恶化 水资源缺乏 流域水污染 事故发生
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Buoyancy leads to high productivity of the Changjiang diluted water:a note 被引量:1
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作者 CHEN Chen-Tung Arthur 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第6期133-140,共8页
Being the mightiest river emptying into the East China Sea (ECS) and the Pacific Ocean, compounded with the large increase of nitrogen and phosphorus input due to anthropogenic activities, the Changjiang River (Yan... Being the mightiest river emptying into the East China Sea (ECS) and the Pacific Ocean, compounded with the large increase of nitrogen and phosphorus input due to anthropogenic activities, the Changjiang River (Yangtze River) has become a dominating source of these nutrients to the estuary. The high nutrient concentrations notwithstanding, however, outside of the estuary the high biological productivity of the Changjiang diluted water (CDW) are most probably fueled mainly by nutrient-rich subsurface waters originating from the upwelled Kuroshio waters. This is because while the buoyancy of the CDW spreads it out on the ECS continen- tal shelf, the CDW entrains subsurface waters along with the nutrients. Nutrients thus supplied are several times more than those supplied by the Changjiang River. 展开更多
关键词 changjiang river changjiang diluted water NUTRIENTS Three Gorges Dam PRODUCTIVITY BUOYANCY
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A decade of variation of COD in the Changjiang River (Yangtze River) and its variation trend analysis 被引量:1
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作者 WANG Fushun WANG Yuchun ZHANG Jing 《Chinese Journal Of Geochemistry》 EI CAS 2007年第4期366-373,共8页
The average annual value of COD (chemical oxygen demand) fluxes of the Changjiang River (Yangtze River) and its main tributaries in the past decade (i.e., 1991–2000), has been evaluated. Based on the data from the Da... The average annual value of COD (chemical oxygen demand) fluxes of the Changjiang River (Yangtze River) and its main tributaries in the past decade (i.e., 1991–2000), has been evaluated. Based on the data from the Datong Hydrological Station (DHS), it was found that the Dongting Lake drainage basin contributed the greatest water discharge (35.8%) and COD flux (48.3%) among the main tributary drainage basins, followed by the Poyang Lake drainage basin with the contributions of 15.4% and 19.3%,respectively. By the end of the year of 2000, COD flux in the Changjiang River rose by almost 45% relative to that in the year of 1991, reaching about 1941000 ton/a at DHS. Statistical analysis revealed that industrial wastewater discharge, as well as COD in it, was found decreasing in the same period, due to the gradual reinforcement of environmental management. Moreover, correlation analysis indicated that non-point pollution from agriculture and increasing discharge of domestic sewages caused by rapid growth of population along the Changjiang River drainage valley should be responsible for the high COD. Furthermore, with the current trend of population growth and agricultural development in this basin, water quality of the Changjiang River, in terms of COD level, is going to deteriorate in the near future. Thus, the rational applications of fertilizers and pesticides in agriculture and the proper treatment of domestic sewages before they are discharged would be the most concerned controlling parameters. 展开更多
关键词 长江 排水盆地 水质量 种群
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Analysis of Micro Organic Compound Pollution in Major City River Reaches of the Main Stem of the Changjiang River
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作者 WANG Che-huaSenior Engineer, Changjiang River Water Environmental Monitoring Center, Wuhan 430051, China PENG BiaoSenior Engineer, Changjiang River Water Environmental Monitoring Center, Wuhan 430051, China 《人民长江》 北大核心 2002年第S1期63-68,共6页
It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was pe... It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was performed on micro organic compounds in the water, bottom material and fish bodies which were sampled from major city river reaches of the Changjiang River. Based on the test result, researchers described and analyzed the sorts, concentration level and distribution features of micro organic compounds. A comprehensive evaluation was conducted by adopting the method of MEG (Multimedia Environmental Goals). The study indicated that ① the water body of major city river reaches of the Changjiang River has been generally polluted. In the test, totally 12 types with 308 kinds of organic compounds were detected. The main pollutants were paraffins, PAHs and lipids; and ② micro organic pollutant content in fish bodies was generally higher than that in bottom material which is in turn higher than that in water; and ③ pollution is relatively severe in the river reaches of mid-to-large comprehensive industrial cities with fairly great TAS (Total Ambient Severity) of public health and ecological system. 展开更多
关键词 MICRO organic compounds content level distribution features water POLLUTION situation MAJOR CITY river reaches main stem of the changjiang river
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A numerical study on water diversion ratio of the Changjiang(Yangtze)estuary in dry season 被引量:18
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作者 李路 朱建荣 +1 位作者 吴辉 王彪 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期700-712,共13页
We studied the flood, ebb and tidal averaged along (net) water diversion ratio (WDR) during dry season in the Changjiang (Yangtze) estuary, China, along with the effects of northerly wind, river discharge, tide and th... We studied the flood, ebb and tidal averaged along (net) water diversion ratio (WDR) during dry season in the Changjiang (Yangtze) estuary, China, along with the effects of northerly wind, river discharge, tide and their interactions on WDR using the improved version of three-dimensional numerical model ECOM. Using data for annual mean wind speed and river discharge during January, we determined that the flood, ebb, net WDR values in the North Branch of the estuary were 3.48%, 1.68%,-4.06% during spring tide, and 4.82%, 2.34%,-2.79% during neap tide, respectively. Negative net WDR values denote the transport of water from the North Branch into the South Branch. Using the same data, the corresponding ratios were 50.09%, 50.92%, 54.97%, and 52.33%, 50.15%, 43.86% in the North Channel and 38.56%, 44.78%, 103.96%, and 36.92%, 43.17%, 60.97% in the North Passage, respectively. When northerly wind speed increased, landward Ekman transport was enhanced in the North Branch, increasing the flood WDR, while the ebb WDR declined and the net WDR exhibited a significant decrease. Similarly, in the North Channel, the flood WDR is increased, the ebb WDR reduced, and the net WDR showed a marked decrease. In the North Passage, the flood WDR also increased while the ebb and net WDR declined. As the river discharge increased, the flood and ebb WDR of the North Branch increased slightly and the net WDR increased markedly. In the North Channel the flood and ebb WDR changed very slightly, while the net WDR declined during spring tides and increased during neap tides. The WDR in the North Passage changed slightly during flood and ebb tides while the net WDR showed a marked increase. The WDR values of different bifurcations and the responses to northerly wind, river discharge, and tide are discussed in comparison with variations in river topography, horizontal wind-induced circulation, and tidal-induced residual current. 展开更多
关键词 数值研究 分流比 长江 旱季
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