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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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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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Regional Geochemical Characteristics and Influence Factors of Soil Elements in the Pearl River Delta Economic Zone, China 被引量:2
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作者 Lei Dou Tingting Li 《International Journal of Geosciences》 2015年第6期593-604,共12页
Soil heavy metal pollution is one of the main environmental problems in Pearl River Delta Economic?Zone of China. Based on multi-purpose regional geochemical survey, regional eco-geochemical assessment, local eco-geoc... Soil heavy metal pollution is one of the main environmental problems in Pearl River Delta Economic?Zone of China. Based on multi-purpose regional geochemical survey, regional eco-geochemical assessment, local eco-geochemical assessment and comprehensive appraisal, the eco-geochemical survey and assessment in Pearl River Delta Economic Zone of 41,698 km2?were completed. Samples from soils were collected in accordance with the two-layer grid method. Totally 54 elements and indicators for soils were determined. Compared to deep soils, the sampled surface soils are enriched in OrgC, N, P, Cd, S,Hg, Ag, B, Au, S and poor with As, Ni, I, Co, Cr, V, MgO, Sc, Al2O3, Fe2O3?etc. The characteristics of geochemical reference value of element in soil that inherited soil parent material and regional elements combined features reflected that the elements enriched in the soil was interrelated with acid rock, sandstone and shale. The spatial distribution characteristics of element regional geochemistry were conditional by regional environmental geological conditions,and effected by human activities. The Pearl River Delta plain is a typical geochemical landscape area with regional anomaly of multiple-elements. The north, western and eastern parts of the Pearl River Delta Economic Zone are quite different in geochemical features due to regional geological background, soil parent materials, geomorphic characteristics and human activities. Environment quality evaluation results show that the grade I and grade II soil accounted for 19.9% and 57.3% of the total area. Many samples that widely distributed in the economic developed of Pearl River Delta Plain area reached the third-grade of national soil environment standard. The soil enriched in Cd, Hg, As, and the area ratio accounting for 22.8% of the total area. It is mainly controlled by the geochemical background, the Pearl River Delta formation evolution process, especially the marine transgression process lead to Cd, Cu, Zn and Pb enrichment in Pearl River Delta plain. At the same time, under the influence of higher pressure of human activities, all kinds of exogenous input material carrying heavy metal pollutants on soil environmental quality also could not to ignore. 展开更多
关键词 regional GEOCHEMICAL Characteristic Soil ELEMENTS Source of ANOMALOUS ELEMENTS influence Factors PEARL river delta Economic Zone China
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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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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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THE REGIONAL DEVELOPMENT IN THE PEARL RIVER DELTA IN NEW TERM
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作者 LU La-chang(Department of Geography,Guangzhou University,Guangzhou 510405,P.R.China) 《Chinese Geographical Science》 SCIE CSCD 2002年第4期309-314,共6页
Since China opening to outside world,the economy in the Pearl(Zhujiang)River Delta(PRD)has been dou-ble digit growth.It has been known as one of mature fast growth areas in the world and become the model and hope of C... Since China opening to outside world,the economy in the Pearl(Zhujiang)River Delta(PRD)has been dou-ble digit growth.It has been known as one of mature fast growth areas in the world and become the model and hope of Chi-nese reformand opening to outside wo rld.The regional development in PRD is the outcome of polarization effects .The polar-ization effects actually are extension of international regional divis ion and a combination of Hongkong’s i nfluence and re-form and open-door policies on the ma inland.Since the 1990s,driven by knowledge-based economy,the PRD has f urther adjusted the industrial structure a nd achieved good progress in upgradi ng industrial structure.Its high te chnology industry has developed quickly and the econom ic internationalization has deepen ed,meanwhile,the region is going th rough transforma-tion and some new trends have begun to appear,which include:university t owns springing up,industrial globalization and the construction of Hi-tech develop ment zones.The paper suggests that w ith the economic growth changing fro m relying on the low level production elements to relying on high level production ele ments,the regional policies in Guan gdong Province should develop correspondingly:1)make a plan to prohibite the blind con struction in innovative spatial con struc-tions;2)make measures to attract the overseas talents to establish a pool of talen t;3)work out the favorable policies for absorbing larger capital;4)formulate the policy of attracting a cluster of industries to speed up the upgrade of industrial development. 展开更多
关键词 区域发展 珠江三角洲 两极分化 中国 政策 产业结构
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The Influence of the Urban-Rural Income Disparity on the Industrial Structure—Taking the Yangtze River Delta Region as an Example
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作者 Yan Chen Yuanyuan Sun Wanbin Li 《Open Journal of Statistics》 2022年第3期303-323,共21页
In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. ... In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. However, this paper is from another perspective, based on the social background of high-quality development, the main study is the impact mechanism of urban and rural income gap on the industrial structure, taking the Yangtze River Delta as the main research object, and specifically selecting 22 central cities in the Yangtze River Delta region, which is also one of the highlights of this study. The regression model is constructed by using the intermediary effect, and the four intermediary variables of fiscal expenditure (M<sub>1</sub>), fixed asset investment (M<sub>2</sub>), number of patent applications (M<sub>3</sub>), and total import and export (M<sub>4</sub>) are selected, which represent the role of the government, fixed asset investment, scientific and technological level and opening-up level, and study and analyze the inherent influence mechanism between each variable. Before doing specific research, I consulted the papers and literature of many other outstanding scholars, among which Cheng Yuhong and Cheng Chi’s “The Influence Mechanism of industrial structure of urban and rural income gap” [1] has great reference value for this paper. According to the research results, under the background of high-quality development in the Yangtze River Delta region, the expansion of the income gap between urban and rural areas will inhibit the upgrading of the industrial structure, so it is necessary to focus on building a new type of urbanization, accelerating the construction of an urban innovation system, optimizing the rural employment structure to narrow the income gap between urban and rural areas, and providing impetus for the continuous upgrading of the industrial structure. 展开更多
关键词 income Gap Between Urban and Rural Areas industrial Structure Upgrading High-Quality Development Normalization of the Epidemic yangtze river delta region Mediation Effect Model SPSS
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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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Spatial and Temporal Variations of Pneumoconiosis in the Pearl River Delta Region in 2006–2015 被引量:4
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作者 LI Xu Dong TU Hong Wei +4 位作者 LIU Yi Ming WEN Xian Zhong YU Hong Wei QU Hong Ying CHEN Qing 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第3期191-195,共5页
Pneumoconiosis is a restrictive lung disease mostly caused by occupational exposure to dust,including silica dust,asbestos,and other fibers.Inhalable particles smaller than 10μm can enter the bronchioles,injure lung ... Pneumoconiosis is a restrictive lung disease mostly caused by occupational exposure to dust,including silica dust,asbestos,and other fibers.Inhalable particles smaller than 10μm can enter the bronchioles,injure lung cells,and induce lung fibrosis.This hard-to-cure disease places a substantial burden on patients and society[1]. 展开更多
关键词 Spatial and Temporal VARIATIONS of PNEUMOCONIOSIS in the PEARL river delta region in 2006 delta
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Legislation on protection of drinking water sources and local management practices in the Pearl River Delta region of China 被引量:6
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作者 Zhigang Wang Yang Liu +2 位作者 Yingzhi Li Peng Zhao Jiangyu Yu 《Chinese Journal of Population,Resources and Environment》 2016年第2期144-152,共9页
The protection of drinking water sources is vital to urban development and public health.In this study,the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region w... The protection of drinking water sources is vital to urban development and public health.In this study,the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region was investigated using a method combining Google Earth with the field survey.The gaps between management practices and legislation requirements were analyzed.Finally,several countermeasures for water resource protection were proposed as follows:to promote delineation in a more scientific way,to safeguard the sanctity of the law,to make better plan on water saving,and to encourage public participation in supervision and management. 展开更多
关键词 Pearl river delta region drinking water source protection area for drinking water source COUNTERMEASURES
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Large-scale Migration of Fluids toward Foreland Basins during Collisional Orogeny: Evidence from Triassic Anhydrock Sequences and Regional Alteration in the Middle-Lower Yangtze Area 被引量:3
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作者 HOUZengqian YANGZhusen LIYinqing ZENGPusheng MENGYifeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期203-220,共18页
The middle-lower Yangtze area underwent a series of complex tectonic evolution, such as Hercynian extensional rifting, Indosinian foreland basining, and Yanshanian transpression-transtension, resulting in a large dist... The middle-lower Yangtze area underwent a series of complex tectonic evolution, such as Hercynian extensional rifting, Indosinian foreland basining, and Yanshanian transpression-transtension, resulting in a large distinctive Cu-Fe-Au metallogenic belt. In the tectonic evolution, large-scale migration and convergence of fluids toward foreland basins induced during the collisional orogeny of the Yangtze and North China continental blocks were of vital importance for the formation of the metallogenic belt. Through geological surveys of the middle-lower Yangtze area, three lines of evidence of large-scale fluid migration are proposed: (1) The extensive dolomitic and silicic alteration penetrating Cambrian-Triassic strata generally occurs in a region sandwiched between the metallogenic belt along the Yangtze River and the Dabie orogenic belt, and in the alteration domain alternately strong and weak alteration zones extend in a NW direction and are controlled by the fault system of the Dabie orogenic belt; it might record the locus of the activities of long-distance migrating fluids. (2) The textures and structures of very thick Middle-Lower Triassic anhydrock sequences in restricted basins along the river reveal the important contribution of the convergence of regional hot brine in restricted basins and the chemical deposition or their formation. (3) Early-Middle Triassic syndepositional iron carbonate sequences and Fe-Cu-Pb-Zn massive sulfide deposits alternate with anhydrock sequences or are separated from the latter, but all of them occur in the same stratigraphic horizon and are intimately associated with each other, being the product of syndeposition of high-salinity hot brine. According to the geological surveys, combined with previous data, the authors propose a conceptual model of fluid migration-convergence and mineralization during the Dabie collisional orogeny. 展开更多
关键词 large-scale migration of fluids collisional orogeny anhydrock sequence regional alteration middle-lower yangtze river
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Remote Monitoring of Expansion of Aquaculture Ponds Along Coastal Region of the Yellow River Delta from 1983 to 2015 被引量:18
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作者 REN Chunying WANG Zongming +4 位作者 ZHANG Bai LI Lin CHEN Lin SONG Kaishan JIA Mingming 《Chinese Geographical Science》 SCIE CSCD 2018年第3期430-442,共13页
Aquaculture ponds are one of the fastest-growing land use types in valuable and fertile coastal areas and have caused serious environmental problems. Quantitative assessment of the extent, spatial distribution, and dy... Aquaculture ponds are one of the fastest-growing land use types in valuable and fertile coastal areas and have caused serious environmental problems. Quantitative assessment of the extent, spatial distribution, and dynamics of aquaculture ponds is of utmost importance for sustainable economic development and scientific management of land and water resources in the coastal area. An object-oriented classification approach was applied to Landsat images acquired over three decades to investigate the long-term change of aquaculture ponds in the coastal region of the Yellow River Delta. The results indicated that the aquaculture ponds in the study area undergone a sharp expansion from 40.38 km^2 in 1983 to 1406.89 km^2 in 2015, and the fast expansion occurred during the period of 2010–2015 and 1990–2000. Natural wetlands, especially mudflat, and cropland were main land use types contributing to the increase of aquaculture ponds. The patches of aquaculture ponds were consequently prevalence in the north of the Yellow River Estuary and landscape metrics indicated an increase of the aquaculture ponds of the study area in the quantity and complexity. The expansion of aquaculture ponds inevitably had negative effects on the coastal environment, including loss of natural wetlands, water pollution and land subsidence, etc. The results from this study provide baseline data and valuable information for efficiently planning and managing aquaculture practices and for effectively implementing adequate regulations and protection measures. 展开更多
关键词 黄河三角洲 水产业 沿海 LANDSAT 环境问题 科学管理 经济开发 区域调查
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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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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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Aerosol Optical Properties and Radiative Impacts in the Pearl River Delta Region of China during the Dry Season 被引量:1
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作者 Boru MAI Xuejiao DENG +7 位作者 Zhanqing LI Jianjun LIU Xiang'ao XIA Huizheng CHE Xia LIU Fei LI Yu ZOU Maureen CRIBB 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第2期195-208,共14页
Aerosol optical properties and direct radiative effects on surface irradiance were examined using seven years (2006-2012) of Cimel sunphotometer data collected at Panyu--the main atmospheric composition monitoring s... Aerosol optical properties and direct radiative effects on surface irradiance were examined using seven years (2006-2012) of Cimel sunphotometer data collected at Panyu--the main atmospheric composition monitoring station in the Pearl River Delta (PRD) region of China. During the dry season (October to February), mean values of the aerosol optical depth (AOD) at 550 nm, the Angstrom exponent, and the single scattering albedo at 440 nm (SSA) were 0.54, 1.33 and 0.87, respectively. About 90% of aerosols were dominated by fine-mode strongly absorbing particles. The size distribution was bimodal, with fine-mode particles dominating. The fine mode showed a peak at a radius of 0.12 μm in February and October (- 0.10 μm3 μm-2). The mean diurnal shortwave direct radiative forcing at the surface, inside the atmosphere (FATM), and at the top of the atmosphere, was -33.4± 7.0, 26.1 ± 5.6 and -7.3 ±2.7 W m-2, respectively. The corresponding mean values of aerosol direct shortwave radiative forcing per AOD were -60.0 ±7.8, 47.3 ± 8.3 and -12.8 ±3.1 W m-2, respectively. Moreover, during the study period, FATM showed a significant decreasing trend (p 〈 0.01) and SSA increased from 0.87 in 2006 to 0.91 in 2012, suggesting a decreasing trend of absorbing particles being released into the atmosphere. Optical properties and radiative impacts of the absorbing particles can be used to improve the accuracy of inversion algorithms for satellite-based aerosol retrievals in the PRD region and to better constrain the climate effect of aerosols in climate models. 展开更多
关键词 aerosol properties radiative forcing Pearl river delta region dry season
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Arsenic distribution and source in groundwater of Yangtze River Delta economic region, China 被引量:1
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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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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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