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关于长江九江段"河长制"工作的思考 预览
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作者 张心月 黄琴 简洋洋 《环境与发展》 2019年第10期254-254,256共2页
近年来,江西坚持走生态优先的发展之路,着力打造“美丽中国的‘江西样板’”[1]。河网密布的江西,在河流治理方面成效显著,但仍存在不足之处。本文从长江九江段河长制工作的实践出发,简要介绍了九江河长制的发展现状,对其治理成效、突... 近年来,江西坚持走生态优先的发展之路,着力打造“美丽中国的‘江西样板’”[1]。河网密布的江西,在河流治理方面成效显著,但仍存在不足之处。本文从长江九江段河长制工作的实践出发,简要介绍了九江河长制的发展现状,对其治理成效、突出点以及目前河长制发展存在的困境进行了总结,并从治理方案、配套机制设置的角度提出了进一步发展的思考。 展开更多
关键词 长江 九江 河长制 河流管理
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深水航道对江苏港口的推动作用及港口发展策略分析 预览
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作者 许麟 马轶玮 +1 位作者 谭志国 应翰海 《水运工程》 北大核心 2019年第10期9-13,25共6页
长江南京以下12.5m深水航道工程的实施,有力地提升了长江干线江苏段的航道通过能力。针对江苏沿江港口如何依托深水航道推动自身发展的问题,在分析深水航道对到港船舶大型化提升、航运成本下降、运输组织优化、沿江产业转型升级等方面... 长江南京以下12.5m深水航道工程的实施,有力地提升了长江干线江苏段的航道通过能力。针对江苏沿江港口如何依托深水航道推动自身发展的问题,在分析深水航道对到港船舶大型化提升、航运成本下降、运输组织优化、沿江产业转型升级等方面的促进作用的基础上,提出完善和畅洲水道航道条件、整合港口资源和优化布局、加强港口基础设施建设、优化临港产业布局、改善口岸通关政策等建议。 展开更多
关键词 长江 深水航道 江苏沿江港口 发展策略
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Structural characteristics of river networks and their relations to basin factors in the Yangtze and Yellow River basins
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作者 CHEN XiaBin WANG YiChu NI JinRen 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第11期1885-1895,共11页
The integration of rivers and basins highly implies the possible existence of certain relationships between hierarchical characteristics of river networks and primary basin factors.Here we investigated river networks ... The integration of rivers and basins highly implies the possible existence of certain relationships between hierarchical characteristics of river networks and primary basin factors.Here we investigated river networks in two large basins,the Yangtze River and the Yellow River,characterized with basic factors such as annual precipitation,slope,soil erodibility and vegetation.Hierarchical analysis demonstrated a fair self-similarity of river networks at the stream-order 1-5 in both rivers,described by the structural parameters including bifurcation ratio,side-branching ratio,drainage density,and length of headwater-river.Besides precipitation,basin slope was essential in shaping river networks in both basins,showing a significant positive correlation(R^2=0.39-0.85)to bifurcation ratio,side-branching ratio,and drainage density.Given the same basin slope(5°-15°),the higher soil erodibility and sparse vegetation would promote greater side-branching ratio and drainage density in the Yellow River,which were estimated 11.97%and 63.70%larger,respectively than those in the Yangtze River.This study highlights the importance to formulate basin-specific strategies for water and soil conservation in terms of different structures of river networks. 展开更多
关键词 river network structural characteristics basin factor Yangtze River Yellow River
基于生态河湖理念的水利工程运行管理研究 预览
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作者 孙超君 邵园园 姚旺 《中国水利》 2019年第20期33-35,共3页
基于生态河湖理念,研究近年秦淮新河水利工程运行管理情况,对新环境新形势新要求下运行管理中存在的问题及原因进行了分析,就进一步改善和提高工程管理提出合理对策、建议,对提升水利工程管理水平具有一定的借鉴意义。
关键词 生态河湖 秦淮河流域 长江 秦淮新河 水质
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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
The barrier river reach identification and classification in the Middle Yangtze River
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作者 Jinwu TANG Chunyan HU +4 位作者 Xingying YOU Yunping YANG Xiaofeng ZHANG Jinyun DENG Meng CHEN 《地球科学前沿:英文版》 CSCD 2019年第3期596-613,共18页
Adjustments of upstream river regimes are one of the main factors affecting downstream fluvial processes. However, not all adjustments of river regimes will propagate downstream. There are some distinctive river reach... Adjustments of upstream river regimes are one of the main factors affecting downstream fluvial processes. However, not all adjustments of river regimes will propagate downstream. There are some distinctive river reaches where upstream and downstream adjustments have no relevance. However, the irrelevance is neither caused by different river types nor by the different conditions of water and sediment;but rather, the channel boundaries and riverbed morphologies block the propagation effect. These are referred to here as the barrier river reach phenomena. The migration of the thalweg line is the essential reason for causing the propagation effect. Numerous influencing factors for thalweg migration exist, including 1) the average flow rate above the critical bankfull discharge, the average flow rate below the critical bankfull discharge, and their ratio, 2) the ratio of the duration of the aforementioned two periods, 3) the thalweg displacement at the entrance of the river reach, 4) the deflecting flow intensity of the node, 5) the ratio of the river width to water depth, 6) the relative width of the floodplain, and 7) the Shields number. In this study, the correlativity between the measured distances and the restricting indicators of thalweg migration in the Middle Yangtze River over the years was established. The barrier degree of 27 singlethread river reaches was subsequently assessed. These reaches included 4 barrier river reaches;5 transitional reaches transforming from barrier to non-barrier;10 transitional reaches transforming from non-barrier to barrier;and 8 non-barrier river reaches. Barrier river reaches were found to be important for maintaining the stability of the river regime and the transverse equilibrium of sediment transport in the downstream reaches. To some extent, the barrier river reaches may protect the natural dynamical properties from being destroyed by artificial river regulation works. Thus, they are of great significance for river management. 展开更多
关键词 the BARRIER RIVER REACH YANGTZE RIVER channel adjustment THALWEG migration IDENTIFICATION and classification
变化环境下天生港水道规划治理调整方案效果研究 预览
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作者 闻云呈 罗龙洪 +1 位作者 杜德军 夏云峰 《水道港口》 2019年第3期293-298,共6页
天生港水道位于澄通河段,是一条分流比仅占1%~2%、涨潮流占优的支汊。为稳定河势、促进地方经济发展,水利部门对天生港水道整治进行了规划。此后随着上游来水来沙条件变化,周边深水航道、桥梁及沿岸港口码头等诸工程的建设,河床地形发... 天生港水道位于澄通河段,是一条分流比仅占1%~2%、涨潮流占优的支汊。为稳定河势、促进地方经济发展,水利部门对天生港水道整治进行了规划。此后随着上游来水来沙条件变化,周边深水航道、桥梁及沿岸港口码头等诸工程的建设,河床地形发生调整,特别是华泰重工等企业位于规划切滩范围内,为适应新的水沙和工程环境,降低规划工程实施的难度,文章通过数模计算和物模试验,对原规划方案进行了深化研究。调整方案减小了天生港水道进口的切滩宽度,增加疏浚范围及深度。研究表明,调整方案实施后的效果与原方案基本一致,对促进地方经济发展有着重要的意义。 展开更多
关键词 长江 澄通河段 天生港水道 横港沙 整治规划 深化研究
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长江洪水对鄱阳湖倒灌影响及微模型研究进展综述 被引量:1
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作者 王志寰 范红霞 +1 位作者 朱立俊 刘贝贝 《泥沙研究》 CSCD 北大核心 2019年第1期59-66,共8页
长江洪水对鄱阳湖的倒灌现象是江湖关系的研究内容之一。倒灌过程对江湖水沙交换及流域水环境保护、水生态安全维护和水资源配置等具有重要影响。分析了江湖倒灌现象及其特有的水文、泥沙性质,阐述了长江对鄱阳湖倒灌的作用机理和发生条... 长江洪水对鄱阳湖的倒灌现象是江湖关系的研究内容之一。倒灌过程对江湖水沙交换及流域水环境保护、水生态安全维护和水资源配置等具有重要影响。分析了江湖倒灌现象及其特有的水文、泥沙性质,阐述了长江对鄱阳湖倒灌的作用机理和发生条件,并从旱涝灾害、水沙交换和水环境生态三个方面系统总结了倒灌产生的江湖效应研究成果。在归纳以往江湖倒灌研究方法和成果的基础上,从相似理论、相似条件和微模型倒灌研究关键技术等方面,探讨了未来可采用微型河工模型试验新技术,开展长江和鄱阳湖这类大范围江湖作用关系研究的可能性。 展开更多
关键词 长江 鄱阳湖 倒灌 江湖关系 微模型试验
GRACE observed mass loss in the middle and lower Yangtze basin
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作者 Jiangjun Ran Natthachet Tangdamrongsub +3 位作者 Junchao Shi Changqing Wang Lihui Wang Xiaoyun Wan 《大地测量与地球动力学:英文版》 2019年第2期157-162,共6页
Anthropogenic architectures have a significant impact to the environment. The Three Gorges Dam(TGD),as the largest dam in the world, is a typical example, and has influenced the mass anomalies transported by the flow ... Anthropogenic architectures have a significant impact to the environment. The Three Gorges Dam(TGD),as the largest dam in the world, is a typical example, and has influenced the mass anomalies transported by the flow downstream in the Yangtze River since June 2003. However, the evidence of TGD influence on downstream mass transportation is not documented. In this study, we analyze the monthly gravity solutions from GRACE to investigate the downstream mass variations of Yangtze River. From our results,the considerable mass loss is detected in the downstream of TGD. By comparing our estimations with the in situ water level data of TGD, we find that the mass variations derived from GRACE at Datong station decreases shortly after the impoundment of TGD. This confirms a strong connection between them.Furthermore, by comparing with the in situ sediment load and river discharge at Yichang and Datong gauging stations, we find that the sediment load data shows a similar mass loss signature while the river discharge of both stations has stay at a relative stable level. This indicates that further study is still needed to understand the mechanism better. 展开更多
关键词 GRACE Mass loss The YANGTZE RIVER BASIN Sediment load RIVER discharge
Comparison of detrital mineral compositions between stream sediments of the Yangtze River (Changjiang) and the Yellow River (Huanghe) and their provenance implication 预览
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作者 Zhong-bo Wang Ri-hui Li +4 位作者 Shou-ye Yang Feng-long Bai Xi Mei Jian Zhang Kai Lu 《中国地质(英文)》 2019年第2期169-178,共10页
A comparative comparative study on the detrital mineral composition of stream sediments of the Yangtze River (Changjiang) and Yellow River (Huanghe) shows that, light minerals of the Yangtze River basin were mainly qu... A comparative comparative study on the detrital mineral composition of stream sediments of the Yangtze River (Changjiang) and Yellow River (Huanghe) shows that, light minerals of the Yangtze River basin were mainly quartz, feldspar, and detritus, the compositional characteristics of light minerals differed among tributaries, the main stream had a generally higher maturity index than tributaries;heavy mineral content tended to decrease progressively from the upper stream to lower stream of the Yangtze River, the primary assemblage was magnetite-hornblende-augite-garnet-epidote, and diagnostic minerals of different river basins were capable of indicating the nature and distribution of the source rock. Detrital mineral assemblages in sediments of tributaries and the main stream of the Yellow River were basically similar, Primary heavy mineral assemblage was opaque mineral-garnet-epidote-carbonate mineral and alteration mineral. Variations in the contents of garnet, opaque mineral, and hornblende mainly reflected the degree of sedimentary differentiation in suspended sediment and the hydrodynamic intensity of a drainage system. The heavy mineral differentiation index F revealed sedimentary differentiation of diagnostic detrital mineral composition due to changes in regional hydrodynamic intensity and can serve as an indicator for studying the dynamic sedimentary environment of a single-provenance river and the degree of sedimentary differentiation of its detrital minerals. Changes in detrital mineral content of the Yellow River was not completely controlled by provenance but reflected gravity sorting of the detrital mineral due to variations in the ephemeral river hydrodynamic intensity and sedimentary environment, however the index changing of Yangtze River were mainly influenced by the complex sediment sources. Therefore caution must be exercised in using the detrital mineral composition of marginal sea to determine the contribution of the Yangtze River and Yellow River. 展开更多
关键词 Yangtze RIVER Yellow RIVER Sediment DETRITAL mineral PROVENANCE IMPLICATION
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分汊河道平衡水深方法 预览 被引量:1
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作者 孙志林 高运 许丹 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2019年第1期61-66,共6页
为了研究分汊河道的河床演变与航道水深,本文基于水力几何形态关系,得到分汊河道平衡水深计算方法。该方法对于不同断面形态的分汊河道均具有适用性,汊道与单一河道过水断面面积之比为分流比的6/7次方。应用于长江南京以下12.5m深水航... 为了研究分汊河道的河床演变与航道水深,本文基于水力几何形态关系,得到分汊河道平衡水深计算方法。该方法对于不同断面形态的分汊河道均具有适用性,汊道与单一河道过水断面面积之比为分流比的6/7次方。应用于长江南京以下12.5m深水航道二期工程,计算得出的落成洲分汊河段断面的平均水深与多年平均水深基本一致,表明了平衡水深理论的可靠性。对福姜沙和世业洲分汊河段工程前的最大通航水深计算,亦与实际情况较为吻合;工程后的预测结果显示工程整治效果明显,世业洲和福姜沙左汊河段均能满足12.5m通航水深的要求,但福北水道仍无法达到12.5m通航水深。平衡水深方法提供了一种除数学模型和物理模型外预测河床演变趋势,计算出航道能维持的平衡水深,丰富了航道整治理论的同时,也为二期工程的实施提供科学依据与理论指导。 展开更多
关键词 水力几何形态 平衡水深 分汊河道 河床演变 长江 航道整治 最大通航水深 汊道选择
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长江流域禁捕渔业生态补偿框架和测算模型 预览
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作者 陈廷贵 兰利 +1 位作者 杨怀宇 唐议 《中国渔业经济》 2019年第4期6-12,共7页
随着长江资源环境保护与经济发展矛盾的日益加剧,渔业资源保护与渔民民生的矛盾也日益突出。渔业生态补偿是遏制长江流域渔业水生生态系统继续恶化的客观需求及重要制度安排。借鉴草原退捕生态补偿和征地补偿测算框架,基于经济学理论和... 随着长江资源环境保护与经济发展矛盾的日益加剧,渔业资源保护与渔民民生的矛盾也日益突出。渔业生态补偿是遏制长江流域渔业水生生态系统继续恶化的客观需求及重要制度安排。借鉴草原退捕生态补偿和征地补偿测算框架,基于经济学理论和物权法,运用机会成本法,得出长江流域禁捕渔业生态补偿标准测算应包含:捕捞收益补偿(捕捞许可证回购)、社会保障补偿(失业、养老和医疗补助)、专用生产设备报废补偿(渔船和网具)三大部分,进而提出每个部分的测算模型,最终得出退捕渔民生态补偿总公式,为长江流域生态保护政策的实施提供有益参考。 展开更多
关键词 长江 禁捕 生态补偿 补偿标准
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Unexpected sedimentation patterns upstream and downstream of the Three Gorges Reservoir: Future risks 预览
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作者 Yifan Huang Jinsheng Wang Mei Yang 《国际泥沙研究:英文版》 SCIE 2019年第2期108-117,共10页
This paper summarizes the latest developments, future prospects, and proposed countermeasures of reservoir sedimentation and channel scour downstream of the Three Gorges Reservoir (TGR) on the Yangtze River in China. ... This paper summarizes the latest developments, future prospects, and proposed countermeasures of reservoir sedimentation and channel scour downstream of the Three Gorges Reservoir (TGR) on the Yangtze River in China. Three key results have been found.(1) The incoming sediment load to the TGR has been significantly lower than expected.(2) The accumulated volume of sediment deposition in the TGR is smaller than expected because the overall sediment delivery ratio is relatively low, and the deposition in the near-dam area of the TGR is still developing.(3) River bed scour in the river reaches downstream of the Gezhouba Dam is still occurring and channel scour has extended to reaches as far downstream as the Hukou reach. Significantly, sedimentation of the TGR is less problematic than expected since the start of operation of the TGR on the one hand;on the other hand, the possible increases in sediment risks from dependence on upstream sediment control, deposition in the reservoir, and scour along middle Yangtze River should be paid more attention.(1) Sediment trapped by dams built along the upper Yangtze River and billion tons of loose materials on unstable slopes produced by the Wenchuan Earthquake could be new sediment sources for the upper Yangtze River. More seriously, possible release of this sediment into the upper Yangtze River due to new earthquakes or extreme climate events could overwhelm the river system, and produce catastrophic consequences.(2) Increasing sediment deposition in the TGR is harmful to the safety and efficiency of project operation and navigation.(3) The drastic scour along the middle Yangtze River has intensified the down-cutting of the riverbed and erosion of revetment, it has already led to increasing risk to flood control structures and ecological safety. It is suggested to continue the Field Observation Program, to initiate research programs and to focus on risks of sedimentation. 展开更多
关键词 YANGTZE River Three Gorges RESERVOIR SEDIMENTATION Risk
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Spatio-temporal analysis of phenology in Yangtze River Delta based on MODIS NDVI time series from 2001 to 2015
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作者 Yongfeng WANG Zhaohui XUE +1 位作者 Jun CHEN Guangzhou CHEN 《地球科学前沿:英文版》 SCIE CAS CSCD 2019年第1期92-110,共19页
Phenology has become a good indicator for illustrating the long-term changes in the natural resources of the Yangtze River Delta.However,two issues can be observed from previous studies.On the one hand,existing time-s... Phenology has become a good indicator for illustrating the long-term changes in the natural resources of the Yangtze River Delta.However,two issues can be observed from previous studies.On the one hand,existing time-series classification methods mainly using a single classifier,the discrimination power,can become deteriorated due to fluctuations characterizing the time series.On the other hand,previous work on the Yangtze River Delta was limited in the spatial domain (usually to 16 cities)and in the temporal domain (usually 2000-2010).To address these issues,this study attempts to analyze the spatiotemporal variation in phenology in the Yangtze River Delta (with 26 cities,enlarged by the state council in June 2016), facilitated by classifying the land cover types and extracting the phenological metrics based on Moderate Resolution Imaging Spectrometer (MODIS)Normalized Difference Vegetation Index (NDVI)time series collected from 2001 to 2015.First,ensemble learning (EL)-based classifiers are used for land cover classification,where the training samples (a total of 201,597)derived from visual interpretation based on GlobelLand30 are further screened using vertex component analysis (VCA),resulting in 600 samples for training and the remainder for validating. Then,eleven phenological metrics are extracted by TIMESAT (a package name)based on the time series, where a seasonal-trend decomposition procedure based on loess (STL-decomposition)is used to remove spikes and a Savitzky-Golay filter is used for filtering.Finally,the spatio-temporal phenology variation is analyzed by considering the classification maps and the phenological metrics.The experimental results indicate that:1)random forest (R.F)obtains the most accurate classification map (with an overall accuracy higher than 96%);2)different land cover types illustrate the various seasonalities;3)the Yangtze River Delta has two obvious regions,i.e.,the north and the south parts,resulting from different rainfall, temperature,and ecosystem conditions;4)the phenology 展开更多
关键词 YANGTZE River Delta MODIS NDVI ENSEMBLE learning land cover classification SPATIO-TEMPORAL PHENOLOGY
长江中下游湖泊生态空间演变过程及影响因素 预览
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作者 张运林 张毅博 +1 位作者 秦伯强 朱广伟 《环境与可持续发展》 2019年第5期33-36,共4页
本文通过对长江中下游湖泊生态空间进行回顾研究,系统地总结了长江中下游湖泊生态空间演变过程和潜在的影响因素。近40年来,长江中下游湖泊面积萎缩严重,生态空间容量锐减,湖泊富营养化久治不愈、蓝藻水华频繁暴发、水生植被严重退化,... 本文通过对长江中下游湖泊生态空间进行回顾研究,系统地总结了长江中下游湖泊生态空间演变过程和潜在的影响因素。近40年来,长江中下游湖泊面积萎缩严重,生态空间容量锐减,湖泊富营养化久治不愈、蓝藻水华频繁暴发、水生植被严重退化,生态空间质量急剧下降。归纳起来,其原因主要来自以下三个方面:(1)历史上长期的围湖造田和围网养殖损害湖泊生态空间容量和质量;(2)长江干支流水库群建设和运行对中下游通江湖泊生态空间产生负面影响;(3)社会经济快速发展和气候变化加剧湖泊生态空间质量退化。建议未来加强长江中下游湖群江湖关系演变的研究,科学确定湖泊生态空间容量的恢复目标及区域;统筹流域发展,布局重点生态工程,扩增湖泊生态空间;加强长江干支流水库群优化调度,保障中下游湖泊生态需水量。 展开更多
关键词 长江 湖泊 生态空间 富营养化
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江苏省长江岸线管控分区与措施研析 预览
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作者 江慧 陈惟肖 《环境影响评价》 2019年第4期16-19,共4页
江苏省地处长江下游,拥有丰富的长江岸线资源。为加强江苏长江岸线资源的科学开发与利用,基于岸线利用遥感调查和GIS分析,对江苏省长江岸线开发利用开展相关研究,主要分析江苏省岸线开发利用现状,总结岸线开发利用实践和岸线管理存在的... 江苏省地处长江下游,拥有丰富的长江岸线资源。为加强江苏长江岸线资源的科学开发与利用,基于岸线利用遥感调查和GIS分析,对江苏省长江岸线开发利用开展相关研究,主要分析江苏省岸线开发利用现状,总结岸线开发利用实践和岸线管理存在的主要问题,对岸线进行综合评价与功能分区,将岸线划分为岸线优先保护区、岸线重点管控区、岸线一般管控区三类空间管控区,并提出对岸线实施分级分区管控,为补充完善江苏省“三线一单”划定提供技术支撑。 展开更多
关键词 “三线一单”划定 岸线管控分区划定 岸线管控措施 江苏 长江
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High-resolution 3D crustal S-wave velocity structure of the MiddleLower Yangtze River Metallogenic Belt and implications for its deep geodynamic setting
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作者 Song LUO Huajian YAO +4 位作者 Qiusheng LI Weitao WANG Kesong WAN Yafeng MENG Bin LIU 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第9期1361-1378,共18页
The Middle-Lower Yangtze River Metallogenic Belt(MLYMB) is an important mineral resource region in China.High-resolution crustal models can provide crucial constraints to understand the ore-forming processes and geody... The Middle-Lower Yangtze River Metallogenic Belt(MLYMB) is an important mineral resource region in China.High-resolution crustal models can provide crucial constraints to understand the ore-forming processes and geodynamic setting in this region. Using ambient seismic noise from 107 permanent and 82 portable stations in the MLYMB and the adjacent area,we present a new high-resolution 3D S-wave velocity model of this region. We first extract 5–50 s Rayleigh wave phase velocity dispersion data by calculating ambient noise cross-correlation functions(CFs) and then use the surface wave direct inversion method to invert the mixed path travel times for the 3D S-wave velocity structure. Checkerboard tests show that the horizontal resolution of the 3D S-wave velocity model is approximately 0.5°–1.0° and that the vertical resolution decreases with increasing noise and depth. Our high-resolution 3D S-wave velocity model reveals:(1) AV-shaped high-velocity zone(HVZ) is located in the lower crust and the uppermost mantle in the study region. The western branch of the HVZ passes through the Jianghan Basin,the Qinling-Dabie orogenic belt and the Nanxiang Basin. The eastern branch, which almost completely covers the main body of the MLYMB, is located near the Tanlu Fault. The low-velocity anomalies between the western and eastern branches are located in the area of the Qinling-Dabie orogenic belt.(2) High-velocity uplifts(HVUs) are common in the crust of the MLYMB,especially in the areas near the Tanlu Fault, the Changjiang Fault and the Yangxin-Changzhou Fault. The intensities of the HVUs gradually weaken from west to east. The V-shaped HVZ in the lower crust and uppermost mantle and the HVUs in the middle and lower crust likely represent cooled mantle intrusive rocks. During the Yanshanian period, fault systems formed in the MLYMB due to the convergence between the South China Plate and the North China Plate, the multiple-direction drifting of the PaleoPacific Plate and its subduction beneath the Eurasian Plate. The deh 展开更多
关键词 Middle-Lower Yangtze River METALLOGENIC Belt AMBIENT noise Surface wave CRUSTAL structure Mineralization dynamics
长江经济带设备制造业效率三重分解及比较研究
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作者 王波 周江 《宏观经济研究》 CSSCI 北大核心 2019年第4期84-97,共14页
本文运用超越对数型随机前沿模型,使用2006年到2016年的投入一产出数据,对长江经济带中的10个省市设备制造业、专用设备制造业和交通运输设备制造业的生产效率展开分解分析。研究表明,技术效率变化对专用设备制造业全要素生产率增长起... 本文运用超越对数型随机前沿模型,使用2006年到2016年的投入一产出数据,对长江经济带中的10个省市设备制造业、专用设备制造业和交通运输设备制造业的生产效率展开分解分析。研究表明,技术效率变化对专用设备制造业全要素生产率增长起阻碍作用,对设备制造业和交通运输设备制造业全要素生产率起促进作用,技术进步变化对三类制造业的全要素生产率增长的促进作用减弱,规模变化作用停滞。长江下游区域的产业全要素生产率有小幅下降,长江中上游区域则小幅增加。多数区域产业出现技术进步偏向劳动转变。产业增长正在由投资驱动向创新驱动转变。 展开更多
关键词 全要素生产率 随机前沿分析 长江经济带 制造业
Water level variation characteristics under the impacts of extreme drought and the operation of the Three Gorges Dam
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作者 Yuanfang CHAI Yitian LI +4 位作者 Yunping YANG Sixuan LI Wei ZHANG Jinqiu REN Haibin XIONG 《地球科学前沿:英文版》 CSCD 2019年第3期510-522,共13页
Under the influence of a climate of extreme drought and the Three Gorges Dam (TGD) operation, the water levels in the middle and lower reaches of the Yangtze River in 2006 and 2011 changed significantly compared with ... Under the influence of a climate of extreme drought and the Three Gorges Dam (TGD) operation, the water levels in the middle and lower reaches of the Yangtze River in 2006 and 2011 changed significantly compared with those in the extreme drought years of 1978 and 1986. To quantitatively analyze the characteristics of water level variations in 2006 and 2011, a new calculation method was proposed, and the daily water level and discharge from 1955-2016 were collected in this study. The findings are as follows: in 2006 and 2011, the water level in the dry season significantly increased, but that in the flood season obviously decreased compared with the levels in 1978 and 1986. Here, we described this phenomenon as “no low-water-level in dry season, no high-water-level in flood season”. Based on the calculation method, the contributions of climate variability and the Three Gorges Dam operation to water level variations in the middle and lower reaches of the Yangtze River were calculated, and the contributions indicated that climate variability was the main reason for the phenomenon of “no low-water-level in diy season, no high-water-level in flood season” instead of flood peak reduction in the flood season and drought runoff implementation in the dry season, which are both induced by TGD. 展开更多
关键词 water level EXTREME DROUGHT CLIMATE the Three Gorges DAM the YANGTZE River BASIN
长江(镇江段)水体和水生生物中汞的污染现状与生态风险评价研究 预览
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作者 王晨希 黄晶 朱君 《环境科学与管理》 CAS 2019年第8期191-194,共4页
采用原子荧光光谱法对长江镇江段水体及水生生物中的汞含量进行测定,分析了长江镇江段水体和水生生物中汞污染现状以及汞的含量分布状况,并采用单项污染指数法对其生态风险进行评价。结果表明:长江镇江段8个采样点的水体中汞含量的平均... 采用原子荧光光谱法对长江镇江段水体及水生生物中的汞含量进行测定,分析了长江镇江段水体和水生生物中汞污染现状以及汞的含量分布状况,并采用单项污染指数法对其生态风险进行评价。结果表明:长江镇江段8个采样点的水体中汞含量的平均值为0.014μg/L,均低于《地表水环境质量标准》第Ⅱ类标准(≤0.05μg/L),表明水体均未受到明显的汞污染;水生生物样品(螺蛳、河蚌和鲫鱼)的汞含量均低于中国《农产品安全质量无公害水产品安全要求》(≤300μg/kg)。 展开更多
关键词 长江水 单项污染指数 水生生物 生态风险评价
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