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Regional Brand and High-quality Development of Fruits in Ethnic Areas of the Yangtze River Economic Belt under the Greater Food Approach
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作者 Li GAO Jianjun ZHANG +2 位作者 Yuanpeng SUN Zhiyang LIU Zhiguo SUN 《Asian Agricultural Research》 2024年第3期1-7,共7页
Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.T... Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.This paper introduces the characteristics of fruit industry in 16 autonomous prefectures and 47 autonomous counties under the jurisdiction of the Yangtze River Economic Belt.It studies the intellectual property resources of brand marks from the aspects of geographical indications,collective trademarks,certification trademarks,well-known trademarks in China and national design patents,and analyzes the main problems of brand and high-quality development of fruit industry in these ethnic autonomous areas.Finally,it puts forward some strategies,such as improving the protection of intellectual property rights of geographical indications,using intellectual property rights of brand signs,building modern seed industry upgrading project,drawing lessons from the experience of thousand villages demonstration project,ensuring that large-scale poverty does not occur,and building a diversified food supply system. 展开更多
关键词 GREATER FOOD APPROACH Fruit industry regional brand The yangtze river Economic Belt ETHNIC areas
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Regional accessibility of land traffic network in the Yangtze River Delta 被引量:9
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作者 ZHANG Li LU Yuqi 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期351-364,共14页
In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to ca... In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to calculate and analyze regional accessibility according to the shortest travel time, generating thus a mark diffusing figure. Based on land traffic network, this paper assesses the present and the future regional accessibilities of sixteen major cities in the Yangtze River Delta. The result shows that the regional accessibility of the Yangtze River Delta presents a fan with Shanghai as its core. The top two most accessible cities are Shanghai and Jiaxing, and the bottom two ones are Taizhou (Zhejiang province) and Nantong With the construction of Sutong Bridge, Hangzhouwan Bridge and Zhoushan Bridge, the regional internal accessibility of all cities will be improved. Especially for Shaoxing, Ningbo and Taizhou (Jiangsu province), the regional internal accessibility will be decreased by one hour, and other cities will be shortened by about 25 minutes averagely. As the construction of Yangkou Harbor in Nantong, the regional external accessibility of the harbor cities in Jiangsu province will be speeded up by about one hour. 展开更多
关键词 regional accessibility land traffic network yangtze river Delta GIS
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Eco-environment range in the source regions of the Yangtze and Yellow rivers 被引量:18
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作者 DING Yongjian,YANG Jianping,LIU Shiyin,CHEN Rensheng,WANG Genxu,SHEN Yongping,WANG Jian,XIE Changwei,ZHANG Shiqing(Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Lanzhou 730000, China) 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期172-180,共9页
Based on geographical and hydrological extents delimited, four principles are identified, as the bases for delineating the ranges of the source regions of the Yangtze and Yellow rivers in the paper.... Based on geographical and hydrological extents delimited, four principles are identified, as the bases for delineating the ranges of the source regions of the Yangtze and Yellow rivers in the paper. According to the comprehensive analysis of topographical characteristics, climate conditions, vegetation distribution and hydrological features, the source region ranges for eco-environmental study are defined. The eastern boundary point is Dari hydrological station in the upper reach of the Yellow River. The watershed above Dari hydrological station is the source region of the Yellow River which drains an area of 4.49×10 4 km 2 . Natural environment is characterized by the major topographical types of plateau lakes and marshland, gentle landforms, alpine cold semi-arid climate, and steppe and meadow vegetation in the source region of the Yellow River. The eastern boundary point is the convergent site of the Nieqiaqu and the Tongtian River in the upstream of the Yangtze River. The watershed above the convergent site is the source region of the Yangtze River, with a watershed area of 12.24×10 4 km 2 . Hills and alpine plain topography, gentle terrain, alpine cold arid and semi-arid climate, and alpine cold grassland and meadow are natural conditions in the source region of the Yangtze River. 展开更多
关键词 the source regions of the yangtze and Yellow rivers eco-environmental range CLC number:X171.1
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Role of permafrost in resilience of social-ecological system and its spatio-temporal dynamics in the source regions of Yangtze and Yellow Rivers 被引量:2
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作者 FANG Yi-ping ZHU Fu-biao +2 位作者 YI Shu-hua QIU Xiao-ping DING Yong-jian 《Journal of Mountain Science》 SCIE CSCD 2019年第1期179-194,共16页
Permafrost is one of the key components of terrestrial ecosystem in cold regions. In the context of climate change, few studies have investigated resilience of social ecological system(SER) from the perspective of per... Permafrost is one of the key components of terrestrial ecosystem in cold regions. In the context of climate change, few studies have investigated resilience of social ecological system(SER) from the perspective of permafrost that restricts the hydrothermal condition of alpine grassland ecosystem. In this paper, based on the structural dynamics, we developed the numerical model for the SER in the permafrost regions of the source of Yangtze and Yellow Rivers, analyzed the spatial-temporal characteristics and sensitivity of the SER, and estimated the effect of permafrost change on the SER. The results indicate that: 1) the SER has an increasing trend, especially after 1997, which is the joint effect of precipitation, temperature, NPP and ecological conservation projects; 2) the SER shows the spatial feature of high in southeast and low in northwest,which is consistent with the variation trends of high southeast and low northwest for the precipitation, temperature and NPP, and low southeast and high northwest for the altitude; 3) the high sensitive regions of SER to the permafrost change have gradually transited from the island distribution to zonal and planar distribution since 1980, moreover, the sensitive degree has gradually reduced; relatively, the sensitivity has high value in the north and south, and low value in the south and east; 4) the thickness of permafrost active layer shows a highly negative correlation with the SER. The contribution rate of permafrost change to the SER is-4.3%, that is, once the thickness of permafrost active layer increases 1 unit, the SER would decrease 0.04 units. 展开更多
关键词 RESILIENCE of social ECOLOGICAL system PERMAFROST PERMAFROST active layer thickness Structural dynamic equation Source regions of yangtze and YELLOW riverS
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Arsenic distribution and source in groundwater of Yangtze River Delta economic region, China 被引量:2
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作者 ZHOU Xun 《Journal of Groundwater Science and Engineering》 2017年第4期343-353,共11页
This thesis focuses Arsenic(As) distribution and occurrence in groundwater of Yangtze River Delta economic region, East China. 2019 groundwater samples were collected to analyze 26 chemical compositions, including As.... This thesis focuses Arsenic(As) distribution and occurrence in groundwater of Yangtze River Delta economic region, East China. 2019 groundwater samples were collected to analyze 26 chemical compositions, including As. The Principal Component Analysis(PCA) was used to find out As source in groundwater. The results show that average As concentration in groundwater of this study is 9.33 μg/l, and maximum As concentration is up to 510 μg/l. The variation coefficient is 314.34%. High arsenic phreatic water(>10 μg/l) distributes along the Yangtze River and its estuary. Weak hydrodynamic conditions, wide p H value variation range and deteriorating environment are dominating factors, especially in Yangtze River Delta. The PCA suggests that arsenic in phreatic water is mainly of natural origin. Part of arsenic may directly originate from sediment organics and be related to organics decomposition. 展开更多
关键词 GROUNDWATER ARSENIC DISTRIBUTION SOURCE yangtze river DELTA economic region
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Changes in stress within grassland ecosystems in the three counties of the source regions of the Yangtze and Yellow Rivers 被引量:2
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作者 Fang, YiPing Qin, DaHe Ding, YongJian 《Journal of Arid Land》 SCIE 2010年第2期116-122,共7页
Based on a database of more than 40 years of second production process and energy flow records for Maduo,Qumalai and Yushu counties,a dynamic model of the stress within grassland ecosys-tems was established using a no... Based on a database of more than 40 years of second production process and energy flow records for Maduo,Qumalai and Yushu counties,a dynamic model of the stress within grassland ecosys-tems was established using a nonlinear regression method for this source regions of the Yangtze and Yel-low Rivers.The results show that dynamic curves of stress within grassland ecosystems in the three coun-ties were in the shape of an inverted 'U' during the period 1965-2007.It also revealed that the variation in actual amount of livestock inventories reflected the general trends of the stress within the grassland eco-systems in the source regions,although there were many other factors for the increase or reduction in grassland ecosystem stress. 展开更多
关键词 the source regions of yangtze and Yellow rivers the stress within grassland ecosystems inverted 'U' model Driver
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Impacts of climate change on glacial water resources and hydrological cycles in the Yangtze River source region,the Qinghai-Tibetan Plateau,China:A Progress Report 被引量:2
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作者 YongPing Shen GuoYa Wang +2 位作者 GenXu Wang JianChen Pu Xin Wang 《Research in Cold and Arid Regions》 2009年第6期475-495,共21页
The Yangtze River Source Region has an area of 137,704 km2.Its mean annual runoff of 12.52 billion m3,which was recorded by the Chumda Hydrological Station in 1961–2000,accounts for only 0.13 percent of the Yangtze R... The Yangtze River Source Region has an area of 137,704 km2.Its mean annual runoff of 12.52 billion m3,which was recorded by the Chumda Hydrological Station in 1961–2000,accounts for only 0.13 percent of the Yangtze River's total annual streamflow.The extensive rivers,lakes,wetlands,glaciers,snow fields,and permafrost of the Yangtze River Source Region,as well as the region's vast alpine grasslands,play a critical role in storing and regulating the flow of water not only in the upper Yangtze River watershed of Qinghai,Sichuan,the Tibet Autonomous Region (TAR) (Tibet) and Yunnan,but also throughout the entire lower Yangtze River basin.Climate change has been the dominant factor in recent fluctuation in the volume of the Yangtze River Source Region's glacier resources.The Chumda Hydrological Station on the lower Tongtian River has registered a mean annual glacial meltwater of 1.13 billion m3 for the period 1961–2000,makes up 9 percent of the total annual runoff.Glacial meltwater makes up a significant percentage of streamflow in the Yangtze River Source Region,the major rivers of the upper Yangtze River Source Region:the Togto,Dam Chu,Garchu,and Bi Chu (Bu Chu) rivers all originate at large glaciers along the Tanggula Range.Glaciers in the Yangtze River Source Region are typical continental-type glaciers with most glacial meltwater flow occurring June–August;the close correlation between June–August river flows and temperature illustrates the important role of glacial meltwater in feeding rivers.Glaciers in the source region have undergone a long period of rapid ablation beginning in 1993.Examination of flow and temperature data for the 1961–2000 period shows that the annual melting period for glacial ice,snow,and frozen ground in the Yangtze River Source Region now begins earlier because of increasing spring temperatures,resulting in the reduction of summer flood season peak runoffs;meanwhile,increased rates of glacier ablation have resulted in more uneven annual distribution of runoff in the source region.The annual glacial meltwater runoff in the Yangtze River Source Region is projected to increase by 28.5 percent by 2050 over its 1970 value with the projected temperature increase of 2℃ and a precipitation increase of 29 mm.As a critical source of surface water for agriculture on the eastern Qinghai-Tibet Plateau and beyond,the mass retreat of glaciers in the Yangtze River Source Region will have enormous negative impacts on farming and livestock-raising ac-tivities in upper Yangtze River watershed,as well as on the viability of present ecosystems and even socioeconomic development in the upper Yangtze River Basin. 展开更多
关键词 climate change glacial water resources hydrological cycles the yangtze river Source region
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The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas 被引量:1
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作者 Ma Zhendong and Shan Guangxiang Geochemistry Institute, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第2期158-170,共13页
The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of diff... The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits. 展开更多
关键词 background of regional lead isotopic compositions tracing action lower and middle reaches of the yangtze river and neighbouring areas
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Exploring Regional Innovation Growth Through A Network Approach:A Case Study of the Yangtze River Delta Region,China 被引量:1
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作者 ZHANG Yiqun ZHANG Jingxiang 《Chinese Geographical Science》 SCIE CSCD 2022年第1期16-30,共15页
As the leading urban agglomeration in China,the Yangtze River Delta(YRD)is experiencing a factor-driven to innovationdriven transition.However,the dynamics of regional innovation growth are not yet fully understood.Th... As the leading urban agglomeration in China,the Yangtze River Delta(YRD)is experiencing a factor-driven to innovationdriven transition.However,the dynamics of regional innovation growth are not yet fully understood.This paper combines the complex network methodology with spatial econometrics to disentangle the contributions of innovation endowments,innovation network flows,and innovation network positions to regional innovation growth,as well as their spatial spillover effects.The primary findings suggest that regional innovation growth results from the networked agglomeration economies,which is shaped by the interactions between agglomeration factors and network factors.Specifically,agglomeration factors play a fundamental role in regional innovation growth.In contrast,network factors,such as the network flows and network positions,may contribute to new path creation by promoting access to external innovation resources.Additionally,the institutional factors show multiplexity in fostering regional innovation patterns.Such findings indicate that the YRD region should shift the innovation growth pattern from competitive involution to mutually beneficial cooperation to reduce regional disparities.In this regard,the institutional capacity of organizing network flows and fostering reciprocal inter-city partnerships has become increasingly critical for promoting sustainable innovation and regional development. 展开更多
关键词 network positions innovation network regional growth yangtze river Delta(YRD) China
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Adaptation Management of Mountain Tourism Service: The Case of the Source Regions of the Yangtze and Yellow River 被引量:6
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作者 FANG Yiping QIN Dahe +1 位作者 DING Yongjian YANG Jianping 《Journal of Mountain Science》 SCIE CSCD 2009年第3期299-310,共12页
Mountain areas are often rich in ecological diversity and recreational opportunities. Mountain tourism is thought to be an effective and important means for maintaining and expanding rural economies and, thus, improvi... Mountain areas are often rich in ecological diversity and recreational opportunities. Mountain tourism is thought to be an effective and important means for maintaining and expanding rural economies and, thus, improving the living conditions of rural societies. As mountain tourism service research is a professional field with several disciplines involved, a multi-disciplinary management platform is needed and it facilitates participation in sustainable mountain development by diverse stakeholders. With the source regions of the Yangtze and the Yellow River as a case study, this paper presents a conceptual framework for an adaptation management of mountain tourism services according to technical, policy, social and economic dimensions. The framework is based on a vulnerability assessment of mountain ecosystems, and can serve as a reference for the development of tourism service in other mountain areas. 展开更多
关键词 旅游管理 黄河源区 旅游服务 长江 山区发展 山地 农村经济 概念框架
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Variation Trends of Hydrology and Water Resources in Yangtze River Delta Region,China and Its Responses to Climate Change 被引量:3
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作者 XU Nai-zheng LIU Hong-ying WEI Feng 《Meteorological and Environmental Research》 2012年第6期13-16,共4页
Global warming has become one of important environmental issues, and will alter the spatial distribution of hydrology and water re- sources through accelerating atmospheric and hydrological cycles. Yangtze River Delta... Global warming has become one of important environmental issues, and will alter the spatial distribution of hydrology and water re- sources through accelerating atmospheric and hydrological cycles. Yangtze River Delta region, an economic center in China, has experienced a re- gional temperature increase since the 1960s, forming a heat island, and the warming rate has improved since the 1990s. The characteristics of hy- drology and water resources changed under regional climate warming. Here, the impacts of climate change on hydrology and water resources were discussed from the aspects of precipitation change, sea level rise, seawater invasion and water pollution in Yangtze River Delta region, China. 展开更多
关键词 Climate change Hydrology and water resources yangtze river Delta region China China
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Vegetation Index Reconstruction and Linkage with Drought for the Source Region of the Yangtze River Based on Tree-ring Data 被引量:1
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作者 LI Jinjian WANG Shu +2 位作者 QIN Ningsheng LIU Xisheng JIN Liya 《Chinese Geographical Science》 SCIE CSCD 2021年第4期684-695,共12页
Variations in vegetation are closely related to climate change, but understanding of their characteristics and causes remains limited. As a typical semi-humid and semi-arid cold plateau region, it is important to unde... Variations in vegetation are closely related to climate change, but understanding of their characteristics and causes remains limited. As a typical semi-humid and semi-arid cold plateau region, it is important to understand the knowledge of long term Normalized Difference Vegetation Index(NDVI) variations and find the potential causes in the source region of the Yangtze River. Based on four tree-ring width chronologies, the regional mean NDVI for July and August spanning the period 1665–2013 was reconstructed using a regression model, and it explained 43.9% of the total variance during the period 1981–2013. In decadal, the reconstructed NDVI showed eight growth stages(1754–1764, 1766–1783, 1794–1811, 1828–1838, 1843–1855, 1862–1873, 1897–1909, and 1932–1945)and four degradation stages(1679–1698, 1726–1753, 1910–1923, and 1988–2000). And based on wavelet analysis, significant cycles of2–3 yr and 3–8 yr were identified. In additional, there was a significant positive correlation between the NDVI and the Palmer Drought Severity Index(PDSI) during the past 349 yr, and they were mainly in phase. However, according to the results of correlation analysis between different grades of drought/wet and NDVI, there was significant asymmetry in extreme drought years and extreme wet years. In extreme drought years, NDVI was positively correlated with PDSI, and in extreme wet years they were negatively correlated. 展开更多
关键词 Normalized Difference Vegetation Index(NDVI) RECONSTRUCTION dendrochronology tree ring Source region of the yangtze river
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The Impacts of Permafrost Change on NPP and Implications:A Case of the Source Regions of Yangtze and Yellow Rivers 被引量:9
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作者 FANG Yiping QIN Dahe +2 位作者 DING Yongjian YANG Jianping XU Keyan 《Journal of Mountain Science》 SCIE CSCD 2011年第3期437-447,共11页
This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolatin... This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression methods.The source regions of the Yangtze and Yellow Rivers were selected as the research areas.Results illustrate that:(1) There is significant non-linear relationship between NPP and GT in various typical years;(2) The maximum value of NPP is 6.17,5.87,7.73,and 5.41 DM·t·hm-2 ·a-1 respectively,and the corresponding GT is 7.1,10.0,21.2,and 8.9 o C respectively in 1980,1990,2000 and 2007;(3) In 1980,the sensitivity of NPP to GT is higher than in 1990,2000 and 2007.This tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1980~2007,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 11%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important research for increasing the adaptation capacity and balancing protection and development. 展开更多
关键词 黄河源区 NPP 长江 冻土变化 三次样条插值函数 净初级生产力 多年冻土地区 线性回归方法
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Climate observation of the Three Gorges Region of the Yangtze River in 2019 被引量:4
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作者 Xianyan Chen Xukai Zou +2 位作者 Qiang Zhang Hongling Zeng Tong Cui 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第3期7-11,共5页
2019年,长江三峡地区年平均气温17.5℃,较常年偏高0.3℃;冬季偏冷,春,夏,秋三季气温均偏高;年高温日数偏多.2019年三峡地区年降水量1035.1毫米,较常年偏少13%;四季降水均偏少;年暴雨日数偏少.2019年,长江三峡地区年平均风速较常年偏大;... 2019年,长江三峡地区年平均气温17.5℃,较常年偏高0.3℃;冬季偏冷,春,夏,秋三季气温均偏高;年高温日数偏多.2019年三峡地区年降水量1035.1毫米,较常年偏少13%;四季降水均偏少;年暴雨日数偏少.2019年,长江三峡地区年平均风速较常年偏大;年平均相对湿度接近常年;酸雨强度弱,为1999年以来的最弱年,近十余年酸雨强度呈现明显的减弱趋势.2019年,长江三峡地区高温过程多,持续时间长;三峡中东部地区出现伏秋连旱;华西秋雨开始早,三峡中西部雨量多. 展开更多
关键词 三峡地区 长江 气候概况 天气和气候事件
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State of the climate over the Three Gorges Region of the Yangtze River in 2018 被引量:6
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作者 ZOU Xukai CHEN Xianyan +2 位作者 ZENG Hongling CUI Tong ZHANG Qiang 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第1期48-54,共7页
2018年长江三峡地区气温较常年偏高,降水量接近常年,暴雨日数少,风速偏大,相对湿度接近常年,酸雨弱。年内高温出现早,持续时间长,强度大;夏季出现阶段性伏旱;暴雨和强降水引发城市内涝。
关键词 长江三峡 气候总结 天气气候事件
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State of the climate in the Three Gorges Region of the Yangtze River basin in 2020 被引量:2
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作者 Tong Cui Xianyan Chen +3 位作者 Xukai Zou Qiang Zhang Shuai Li Hongling Zeng 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第2期7-12,共6页
2020年,长江三峡地区年平均气温17.2℃,接近常年;年平均降水量1530.8毫米,偏多29%,为1961年以来第二多,仅次于1998年.6月,7月降水量及年平均暴雨日数均为1961年以来第二多.平均风速较常年偏大;相对湿度略偏高;各月均无酸雨出现,近十余... 2020年,长江三峡地区年平均气温17.2℃,接近常年;年平均降水量1530.8毫米,偏多29%,为1961年以来第二多,仅次于1998年.6月,7月降水量及年平均暴雨日数均为1961年以来第二多.平均风速较常年偏大;相对湿度略偏高;各月均无酸雨出现,近十余年酸雨强度呈现明显减弱趋势.2020年,三峡地区夏季暴雨洪涝灾害重.分析表明,冷空气频繁南下与西南暖湿水汽丰沛是造成三峡地区6–7月降水异常偏多的直接原因.2020年春季以来,印度洋海温持续偏暖导致西北太平洋副热带高压持续偏强偏南可能是造成6–7月长江流域气候异常的重要原因. 展开更多
关键词 三峡地区 长江 气候状况 天气和气候事件 气象灾害
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Efficiency Pattern and Spatial Strategy of Ports in Yangtze River Delta Region 被引量:2
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作者 JIANG Ziran ZHU Huayou CAO Youhui 《Chinese Geographical Science》 SCIE CSCD 2017年第2期298-310,共13页
This paper measures the efficiency of ports in the Yangtze River Delta Region(YRDR) in 2008 and 2013 using port berth quantity, quay length, and human resources as input indicators, using cargo and container throughpu... This paper measures the efficiency of ports in the Yangtze River Delta Region(YRDR) in 2008 and 2013 using port berth quantity, quay length, and human resources as input indicators, using cargo and container throughput as output indicators, and considering traditional(foreign trade dependence and industrialization level) and modern environmental factors(traffic line density, financial development level, and informatization level). To achieve such aim, this study constructs a multi-stage data envelopment analysis model(DEA) that identifies effective port decision-making units(DMUs) and generates a highly accurate conclusion by eliminating the interference from the exogenous environment and random errors. First, the external environment significantly affects port efficiency, with the traditional environmental factors showing huge fluctuations and the modern environmental factors producing great benefits. Second, the efficiency of ports in YRDR has increased from 2008 to 2013 primarily because of their pure technical efficiency. Third, the weighted standard deviation ellipse(SDE) analysis results reveal that the efficiency pattern of ports significantly deviates from their throughput pattern, while the center of SDE of port efficiency moves from the eastern coastal regions to the northwest regions. Based on these findings, this paper proposes spatial development strategies for YRDR, such as creating an unblocked environment where spatial elements can freely circulate, intensifying port-city joint development, implementing differentiated policies, and focusing on the spatial collaboration of port efficiency. 展开更多
关键词 长江三角洲区域(YRDR ) 移植效率 数据包封分析(DEA ) 模型 随机的边疆分析(SFA ) 超级效率分析
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Evaluation on the High Yielding, Stability and Comprehensive Performances of Check Cultivars in National Cotton Regional Trials in the Yangtze River Valley 被引量:1
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作者 Shiqiao JIN Naiyin XU 《Agricultural Science & Technology》 CAS 2014年第11期1942-1945,1952,共5页
[Objective] This study was to analyze the high yielding, stability, adaptability and main characteristics of check cultivars in national cotton regional trials in the Yangtze River Valley in 2000-2013, with the aim to... [Objective] This study was to analyze the high yielding, stability, adaptability and main characteristics of check cultivars in national cotton regional trials in the Yangtze River Valley in 2000-2013, with the aim to provide theoretical basis for the reasonable selection of check cultivars for cotton regional trials. [Method] GGE biplot analysis method was used to carry out the intensive analysis and comprehensive comparisons on the performances and differences of the 9 major characters of check cultivars, namely, lint cotton yield, stability, and other main traits including boll weight, boll number, lint percentage, fiber length, fiber strength, micronaire value, plant height and seed index. [Result] Ezamian 10 was suitable in the majority of cotton planting regions in the Yangtze River Valley, with the best high yielding ability and perfect yield stability. The yielding ability of Xiangzamian 8 ranked the second, but its stability was the poorest. Xiangzamian 8 was of the specific adaptive cultivar with relatively good performance in high yielding but the poorest stability.The suitable planting areas of Xiangzamian 8 were limited to the cotton planting region around Dongting Lake in Hunan province, Poyang Lake in Jiangxi Province,the Coastal region in Jiangsu Province and Wuhan district in Hubei Province. Xiangzamian 2 performanced poorer in both yielding and stability, while Simian 3ranked first in stability but the last in yielding ability. The dominant character of Xiangzamian 8 and Xiangzamian 2 were high cotton plants and big bolls. Simian 3performanced super in lint percentage and fiber length. Ezamian 10 was strong in cotton boll formation ability, lint cotton yielding, fiber strength and seed size, as well as high micronaire value. [Conclusion] The outstanding performance of Ezamian 10 in high and stable yield in the Yangtze River Valley in recent years has effectively promoted the high yielding ability of candidate varieties in cotton regional trials in the area. 展开更多
关键词 棉花种植 区域试验 长江流域 稳定性 品种 检查 性能 评价
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Variation and relationship between soil moisture and environmental factors in the source region of the Yangtze River from 2005 to 2016
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作者 LingLing Song ZongJie Li +6 位作者 Qing Tian LieFu Wang Jing He RuiFeng Yuan Juan Gui BaiJuan Zhang YueMin Lv 《Research in Cold and Arid Regions》 CSCD 2019年第3期184-193,共10页
This study analyzed soil moisture,soil erosion,and vegetation in the source region of the Yangtze River from 2005 to 2016.We found that soil moisture showed an increasing trend from 2005 to 2009 but decreased from 200... This study analyzed soil moisture,soil erosion,and vegetation in the source region of the Yangtze River from 2005 to 2016.We found that soil moisture showed an increasing trend from 2005 to 2009 but decreased from 2009 to 2016.The surface soil moisture was severely affected by seasonal changes in the source region of the Yangtze River,especially in the soil from 0 to 40 cm.However,seasonal variation of soil moisture deeper than 40 cm was different from that in the upper layer.Soil moisture below 40 cm wasn't affected by the seasonal variation.Soil moisture from 0 to 50 cm and the average thickness of wind deposition showed a positive correlation in the study area from 2005 to 2016.For environmental protection in the source region of the Yangtze River,wind deposition played a role in water retention.Similarly,a positive correlation also existed between the average thickness of wind erosion and soil moisture.Deep-soil moisture was the key factor for vegetation structure on the Qinghai?Tibet Plateau.The results are also helpful for further understanding the variation of soil moisture on the Tibetan Plateau and providing a scientific basis for effectively protecting and controlling the ecological environment in the future. 展开更多
关键词 SOIL moisture SOIL EROSION VEGETATION source region of the yangtze river
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Studies on eco-environmental change in source regions of the Yangtze and Yellow Rivers of China:present and future
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作者 JianPing Yang 《Research in Cold and Arid Regions》 CSCD 2019年第3期173-183,共11页
The source regions of the Yangtze and Yellow Rivers are important in the field of eco-environmental change research in China because of its distinct alpine ecosystem and cryosphere environment. At present, there are t... The source regions of the Yangtze and Yellow Rivers are important in the field of eco-environmental change research in China because of its distinct alpine ecosystem and cryosphere environment. At present, there are three different concepts on the extent of source areas of the Yangtze and Yellow Rivers: hydrological, geographical, and eco-environmental. Over the past decades, annual average air temperature has warmed significantly;moreover, the temperature rise rate increases notably with increase of time of the data series. Annual precipitation has no obvious increase or decrease trend, and the climate has become warm and dry in the source regions. As a result, the cryosphere in the regions has shrunk significantly since 1960 s. A warm and dry climate and changing cryosphere together induced a substantial declination of alpine wetlands, marked decrease in river runoff, significant degradation of alpine grassland, and a reduction of engineering stability.The ecological environment, however, has a tendency for restoration in the regions because the climate has become gradually warm and wet since 2000. Thus, studies on eco-environmental change is transforming from a single element to multidisciplinary integration. Climate change-cryopshere change-physical and socioeconomic impacts/risk-adaptation constitute a chain of multidisciplinary integration research. 展开更多
关键词 CRYOSPHERE CHANGE hydrological system alpine grassland the source regions of the yangtze and Yellow rivers PRESENT and FUTURE
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