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Coordination Mechanism and Empirical Research on Marine Science Technology Innovation and Marine Eco-civilization:A Case Study of Coastal Areas of China
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作者 CHEN Xiaolong LIANG Chenlu DI Qianbin 《Chinese Geographical Science》 SCIE CSCD 2024年第3期468-486,共19页
Marine science technology innovation provides power and guarantees for marine eco-civilization construction,which provides direction and material support for marine science technology innovation.Therefore,the coordina... Marine science technology innovation provides power and guarantees for marine eco-civilization construction,which provides direction and material support for marine science technology innovation.Therefore,the coordinated development of the two is of great significance to the marine economy sustainable development in China’s coastal areas.On the basis of clarifying the connotations of marine science technology innovation and marine eco-civilization in China’s coastal areas from 2006 to 2019,the mechanism for their coordinated development was analysed.A comprehensive indicator system based on the connotation of the two was constructed,and the coordinated development relationship was empirically tested using the coupled coordination model and the panel vector autoregressive(PVAR)model.The results show that:1)the level of China’s coastal marine science technology innovation continues to improve,gradually forming the core of the development of marine science technology innovation in the north,east and south of Shandong,Shanghai and Guangdong;the level of marine eco-civilization development fluctuating upward trend,showing obvious spatial differentiation characteristics.2)The degree of coordination of marine science technology innovation and marine eco-civilization is growing over time.There is no causal relationship between marine science technology innovation and marine eco-civilization in the northern marine economic circle,but there is a two-way causal relationship between the two in the eastern and southern marine economic circles.3)Marine eco-civilization shows a significant positive and continuous impact on marine science technology innovation,and marine science technology innovation shows a long-term,continuous,fluctuating,and lagging impact on marine eco-civilization.The overall role of marine eco-civilization on marine science technology innovation is dominant,and there are significant differences in the impact effects of the two major marine economic circles. 展开更多
关键词 marine science technology innovation marine eco-civilization coordinated development coastal areas of china
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Relationship Between Agriculture and Ecological Deterioration,Restoration and Reconstruction in Loess Plateau Areas of Northwest China 被引量:2
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作者 CHENG Xu( China Agricultural University, Beijing 100094) 《Agricultural Sciences in China》 CAS CSCD 2002年第1期114-120,共7页
A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inte... A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inter-disciplinary approach of ecology, agro-geohistory, and agronomy. It was concluded that the fundamental causes responsible for the ecological deterioration, signed by the poor agro-productivity and serious soil erosion, had been the extensive cropping system by ever-increasing reclamation on semi-drought slope land, where initiated a natural vegetation of brushy grasses with sparse trees, thus suitable only for animal husbandry. Based on an identification of specific actual status of China, several countermeasures of correctly dealing with the relationship between agricultural development and the ecological restoration and reconstruction were proposed, including to get breakthrough first in the transection area by means of the rational use of resources and the raising of agro-system productivity, to promoting 'water conservancy-type ecological agriculture' through the radical shift of traditional production pattern, and the adoption of a policy of proper degree of grain self-reliance, as well as to construct livestock industry base in Northwest China. 展开更多
关键词 Loess Plateau Area of northwest china Agricultural ecology
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Countermeasures and Investigation of Land Circulation in Less Developed Agricultural Area of Henan Province,China 被引量:5
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作者 LI Cong-guo College of Environment and Planning,Henan University,Kaifeng 475004,China 《Asian Agricultural Research》 2010年第4期61-64,共4页
Some places in Henan Province are investigated by using sample surveys and interviews. Result shows that land circulation in less developed agricultural area of Henan Province has the characteristics of small scale,si... Some places in Henan Province are investigated by using sample surveys and interviews. Result shows that land circulation in less developed agricultural area of Henan Province has the characteristics of small scale,single form,short period,and circulation land in economic core region. Problems in land circulation are as follows:slow transfer of rural surplus labor force,hard implementation of fundamental land circulation,complicated mentality towards rural land circulation,many misgivings about land circulation,the unformed social service system of land circulation,and imperfect agricultural risk prevention mechanism for circulated land use. Based on the characteristics of land circulation,suggestions for promoting the land circulation of less developed agricultural areas are put forward in order to solve the problems in land circulation and to lay the foundation for effective implementation of land circulation,such as speeding up the development of urbanization,developing the circulation of collective land,effectively implementing the laws and regulations of rural collective land circulation,transferring land according to law,establishing market mechanism of agricultural land circulation,promoting the agricultural industrialization,establishing market mechanism of agricultural land circulation,promoting the agricultural industrialization,energetically readjusting rural industrial structure,and developing economy with local characteristics. 展开更多
关键词 less developed area LAND CIRCULATION PRESENT situa
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Temporal and spatial variation of annual mean air temperature in arid and semiarid region in northwest China over a recent 46 year period 被引量:24
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作者 Chen, ShaoYong Shi, YuanYuan +1 位作者 Guo, YuZhen Zheng, YanXiang 《Journal of Arid Land》 SCIE 2010年第2期87-97,共11页
We analyzed the 1961-2006 mean surface air temperature data of 138 stations in China’s northwest arid and semi-arid areas(CNASA),to measure climate change in terms of annual mean air temperature changes.We used metho... We analyzed the 1961-2006 mean surface air temperature data of 138 stations in China’s northwest arid and semi-arid areas(CNASA),to measure climate change in terms of annual mean air temperature changes.We used methods of linear regression analysis,multinomial fitting,Empirical Or-thogonal Function(EOF),Rotated Empirical Orthogonal Function(REOF),Mann-Kendall,Glide T-examination,wavelet analysis and power spectrum analysis.The results show that(1) the warming rate of the annual mean air temperature in CNASA was 0.35oC/10a during the 1961-2006 study period.Some places in the west part of Xinjiang and east part of the Qinghai plateau,which is impacted by the terrain of leeward slope,exhibit smaller increasing trends.However,the majority of region has shown distinct warming in line with general global warming;(2) The standard deviation of the annual mean temperature distribution is non-uniform.The south Xinjiang and east Qinghai-south Gansu areas show relatively small standard deviations,but the inter-annual variation in annual mean air temperature in the greater part of the region is high;(3) Inner Mongolia,Shaanxi,Gansu,Ningxia and Tarim Basin are the areas where the temperature changes are most sensitive to the environment.The degree of uniformity in annual mean air temperature increase is higher in the arid and semi-arid area.From the early 1970s,the trend in tempera-ture changed from a decrease to an increase,and there was a marked increase in mean temperature in 1986.After that mean temperature went through a period of rapid increase.The entire area’s 10 hottest years all occurred in or since the 1990s,and 90% of various sub-districts’ hottest years also occurred after 1990.The process of temperature change appears to have a roughly 5-year and a 10-year cycle;(4) An-nual mean air temperature variation has regional differences.In Inner Mongolia-Xinjiang and Shaanxi-Gansu-Ningxia-Qinghai areas,the temperature variation in their northern areas was very different from that in their southern areas;(5) Using the REOF method we divided the region into 4 sub-regions:the Northern region,the Plateau region,the Southern Xinjiang region and the Eastern region.The region’s annual mean air temperature transition has regional differences.The Plateau and Southern Xinjiang re-gions got warmer steadily without any obvious acceleration in the rate of warming.The Northern region’s warming started about 5-years earlier than that of the low latitude Eastern region.The ’Startup region’ of the Qinghai-Tibet Plateau,appears to undergo temperature changes 3 to 10 years earlier than the other regions,and exhibits inter-decadal variations 1 to 2 years ahead of the other regions. 展开更多
关键词 northwest area of china annual mean air temperature climatic warming
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Three Types of Spatial Function Zoning in Key Ecological Function Areas Based on Ecological and Economic Coordinated Development: A Case Study of Tacheng Basin, China 被引量:3
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作者 WANG Guiling YANG Degang +2 位作者 XIA Fuqiang ZHONG Ruisen XIONG Chuanhe 《Chinese Geographical Science》 SCIE CSCD 2019年第4期689-699,共11页
Three types of spatial function zoning is an effective measure for regional environmental protection and orderly development.For ecological and economic coordinated development, spatial function zones should be divide... Three types of spatial function zoning is an effective measure for regional environmental protection and orderly development.For ecological and economic coordinated development, spatial function zones should be divided scientifically to clear its direction of development and protection. Therefore, based on ecological constraints, a beneficial discussion would be about the key ecological function areas adopting the concept of ecological protection restriction and supporting socioeconomic development for spatial function zoning. In this paper, the researchers, taking Tacheng Basin, Xinjiang of China as an example, choose township as basic research unit and set up an evaluation index system from three aspects, namely, ecological protection suitability, agricultural production suitability, and urban development suitability, which are analyzed by using spatial analysis functions and exclusive matrix method. The results showed that: 1) This paper formed a set of multilevel evaluation index systems for three types of spatial function zoning of the key ecological function areas based on a novel perspective by scientifically dividing Tacheng Basin into ecological space, agricultural space, and urban space,which realized the integration and scientific orientation for spatial function at the township scale. 2) Under the guidance of three types of spatial pattern, the functional orientation and suggestions of development and protection was clearly defined for ecological protection zones,ecological economic zones, agricultural production zones, and urban development zones. 3) A new idea of space governance is provided to promote the coordinated and sustainable development between ecology and economy, which can break the traditional mode of thinking about regional economic development, and offers a scientific basis and reference for macro decision-making. 展开更多
关键词 KEY ecological FUNCTION areas township scale SPATIAL FUNCTION ZONING mutual EXCLUSION matrix method coordination of ECOLOGY and development Tacheng Basin china
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THE PROCESS AND STRATEGY OF URBANIZATION DEVELOPMENT IN NORTHWEST CHINA 被引量:2
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作者 张志良 《Chinese Geographical Science》 SCIE CSCD 1995年第3期222-231,共10页
It is pointed out that the proportion of urban population is high but synthetical urbanization level is low in northwest China.The urban spacial distribution is influenced by usage of water resource,exploitation of mi... It is pointed out that the proportion of urban population is high but synthetical urbanization level is low in northwest China.The urban spacial distribution is influenced by usage of water resource,exploitation of mineral resource and constrained by transportation lines. The urban distribution is equipped with beaded characteristic.It reveals that the main obstruction for urbanization are fragile economic basement, weak transportation facilities,low synthetical transportation capacity.It provides strategies of developing modern transportation,strengthening resource exploitation concentratively developing leading industries, establishing self-growh mechanism to improve urbanization level as a whole. 展开更多
关键词 northwest china URBANIZATION URBAN DEVELOPMENT
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A New Discovery on the Deformation Behavior of Shale Gas Reservoirs Affecting Pore Morphology in the Juhugeng Coal Mining Area of Qinghai Province, Northwest China 被引量:5
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作者 WANG Anmin CAO Daiyong +2 位作者 LI Jing JIANG Ailin YANG Chengwei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第5期1932-1933,共2页
Objective The Juhugeng mining area in Qinghai Province of northwest China has attracted wide attention among geologists for it hosts typical coal measure gases.The shale gas reservoirs were reformed by intensive struc... Objective The Juhugeng mining area in Qinghai Province of northwest China has attracted wide attention among geologists for it hosts typical coal measure gases.The shale gas reservoirs were reformed by intensive structural movements during geological periods, 展开更多
关键词 A New Discovery on the Deformation Behavior of Shale Gas Reservoirs Affecting Pore Morphology in the Juhugeng Coal Mining Area of Qinghai Province northwest china
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Industrial Policy Analysis of Restricted Development Zones in Western China——A Study of State-level Main Producing Areas of Agricultural Products and Key Ecological Functional Areas
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作者 Chen Ying 《Contemporary Social Sciences》 2016年第2期74-85,共12页
As one of the important policies of promoting the formation of main functional areas, the industrial policy directly determines the sustainable growth of space control ability of main functional areas. A restricted de... As one of the important policies of promoting the formation of main functional areas, the industrial policy directly determines the sustainable growth of space control ability of main functional areas. A restricted development zone is a type of main functional area which provides agricultural products and ecological products, assures the supply of national agricultural products and the stability of ecosystems, as well as safeguards the ecological functions and agricultural functions of wider regions by restricting its own development. Therefore scientific, complete and operable industrial policy support is needed. Restricted development zones are distributed widely in western China. With the restriction of their main functions, differential industrial policies should be implemented in the development of the restricted development zones: Dealing well with the relationship between industrial development and ecological protection, developing special industries which are friendly to resources and environment and appropriate for local conditions, guiding and encouraging industries to learn from regions with favorable development conditions, orderly withdrawing industries and enterprises adverse to main functions, facilitating industrial structure upgrading, optimizing industrial organization, improving industrial technological level and rationalizing industrial layout. 展开更多
关键词 Western china RESTRICTED development main producing areas of agricultural products KEY ECOLOGICAL functional areas INDUSTRIAL policies
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New Stage of the Northwest China 330 kV Power System Development - A Brief Introduction of System Planning in Northwest China to the Year 2000
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作者 Li Pianwen Northwest Electric Power Design Institute 《Electricity》 1996年第4期37-39,共3页
The system planning of the Northwest China 330 kV Power System from present to the year 2000 is introduced in this paper. Some technical problems arising from the system planning, such as network configuration, system... The system planning of the Northwest China 330 kV Power System from present to the year 2000 is introduced in this paper. Some technical problems arising from the system planning, such as network configuration, system stability and reactive power compensation etc. are also briefly summarized. 展开更多
关键词 New Stage of the northwest china 330 kV Power System Development A Brief Introduction of System Planning in northwest china to the Year 2000 KV
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A study on sustainable development capacity of China's coastal areas using indices dimension reduction method
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作者 WANG Li-ming, YANG Yan-feng, MAO Han-ying, CHEN Wei-min (Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第4期28-36,共9页
Sustainable Development Capacity (SDC) is a comprehensive concept. In order to obtain a relatively objective evaluation of it, many indices of various aspects are often used in assessing index systems. However, the ov... Sustainable Development Capacity (SDC) is a comprehensive concept. In order to obtain a relatively objective evaluation of it, many indices of various aspects are often used in assessing index systems. However, the overlapping information of indices is a frequent source deviating the result from the truth. In this paper, 48 indices are selected as original variables in assessing SDC of China's coastal areas. The mathematical method of dimension reducing treatment is used for eliminating the overlapping information in 48 variables. Five new comprehensive indices are extracted bearing efficient messages of original indices. On the base of new indices values, the sequencing of 12 coastal areas SDC is gained, and five patterns of sustainable development regions are sorted. Then, the leading factors and their relations of SDC in these patterns are analyzed. The gains of research are discussed in the end. 展开更多
关键词 sustainable development capacity dimension reduction china's coastal areas
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Prospects of Power Industry Development in Northwest China
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《Electricity》 1997年第1期3-4,共2页
关键词 Prospects of Power Industry Development in northwest china
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CONSULTATIVE RECOMMENDATIONS ON SUSTAINABLE DEVELOPMENT IN KARST AND ROCK-NAKED MOUNTAIN AREAS OF SOUTHWEST CHINA
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作者 Academic Division of Geoscience and Division of Biology , the CAS 《Bulletin of the Chinese Academy of Sciences》 1995年第2期169-172,共4页
The serious degradation of the ecological environment and the rapid expansion of stone desert have had a serious effect on the economic development of karst and rock-naked mountain areas in Southwest China. Moreover, ... The serious degradation of the ecological environment and the rapid expansion of stone desert have had a serious effect on the economic development of karst and rock-naked mountain areas in Southwest China. Moreover, these areas are still at the initial stage of industrialization, characterized by a greater significance of agriculture to the economy, face sharp contradictions among the population, the arable land and resources, and are suffering because of a shortage of investment. On the basis of this current situation, three recommendations are made in this article: "coordinating the relations among grain, ecology, population and economic development", "increasing the input of science and technology", and "adopting policies consistent with social equity in areas of poverty". 展开更多
关键词 CONSULTATIVE RECOMMENDATIONS ON SUSTAINABLE DEVELOPMENT IN KARST AND ROCK-NAKED MOUNTAIN areas of SOUTHWEST china ROCK ROCK
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Water sustainable development in the Shiyang river basin of northwest China
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《Global Geology》 1998年第1期1-1,共1页
关键词 Water sustainable development in the Shiyang river basin of northwest china
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Spatio-temporal Dynamic Patterns of Rural Area Development in Eastern Coastal China 被引量:4
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作者 LIU Yansui WANG Guogang ZHANG Fugang 《Chinese Geographical Science》 SCIE CSCD 2013年第2期173-181,共9页
The aim of this study is to evaluate the current state of rural area development at the county level in the eastern coastal China. An evaluation index system including 18 factors was developed, and a rural development... The aim of this study is to evaluate the current state of rural area development at the county level in the eastern coastal China. An evaluation index system including 18 factors was developed, and a rural development index (RDI) was constructed to evaluate rural development state in 2000, 2004, and 2008. The quantitative evaluation indicated the following results. 1) This study derived four dominating components by means of principal component analysis, which can explain 78.2% of the total information, namely agricultural production input, the basic condition of agriculture, the comparative effectiveness of grain production, and the household′s own basic conditions. 2) Since the turn of the new millennium, the rural area in the eastern coastal China has experienced a rapid development in general. Well developed, developed, moderately developed and undeveloped rural areas respectively occupied 29.32%, 22.33%, 21.91%, and 10.51% in 2008. 3) The countryside had maintained a sound momentum of developing trend between 2000 and 2008, while the rural development in the eastern coastal China lacked sustainability. And 4) industrialization, urbanization, original economic basis, and location are four major driving forces of the disparity of rural area development in the eastern coastal China. Given these results, the strategies and policies for the improvement of each rural group were put forward. 展开更多
关键词 rural area development rural development evaluation new countryside construction eastern coastal china
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Toxic metal enrichment characteristics and sources of arid urban surface soil in Yinchuan City, China 被引量:2
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作者 ZHANG Mingxin LU Xinwei +1 位作者 SHI Dongqi PAN Huiyun 《Journal of Arid Land》 SCIE CSCD 2018年第4期653-662,共10页
To investigate the environmental quality of the urban surface soil in Yinchuan City, the capital of Ningxia Hui Autonomous Region (Ningxia), China, we sampled surface soil and measured the concentrations of 8 toxic ... To investigate the environmental quality of the urban surface soil in Yinchuan City, the capital of Ningxia Hui Autonomous Region (Ningxia), China, we sampled surface soil and measured the concentrations of 8 toxic metals (Pb, Cr, Cu, Zn, Co, Bi, Ni and V) using X-ray fluorescence spectrometry. The enrichment characteristics and sources of these toxic metals in the soil were analyzed by the enrichment factor (EF) and multivariate statistical analysis. The results showed that the mean concentrations of these toxic metals in the soil samples were 25.0, 109.1, 16.8, 26.0, 37.2, 2.7, 25.3 and 59.9 mg/kg for Pb, Cr, Cu, Zn, Co, Bi, Ni and V, respectively, which were 1.2, 1.8, 0.8, 0.4, 3.2, 8.7, 0.7 and 0.8 times of the corresponding background values of Ningxia soil, respectively. The variations of Pb, Zn, Co, Bi and Ni concentrations in the surface soil of Yinchuan were larger than those of the other metals. Our results also showed that the toxic metals investigated in the soil had different enrichment levels. Both Co and Bi were significantly enriched, whereas Cr was only moderately enriched in the soil. There was a deficiency or minimal enrichment of the other toxic metals in the soil. Source analysis results based on the concentration, enrichment characteristics and multivariate statistical analysis indicated that Cr, V and Ni originated from a combination of fossil fuel combustion, traffic pollution and natural occurrence. Pb, Cu and Zn were predominantly derived from natural and traffic sources, while Co and Bi primarily originated from construction sources. 展开更多
关键词 toxic metals urban surface soil enrichment factor arid area northwest china
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The Influence and the Countermeasures about Water Resources in Northwest of Climate Change 被引量:2
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作者 DI Shao-hua XIE Li-yong NING Da-ke 《Meteorological and Environmental Research》 CAS 2011年第6期51-54,60,共5页
[Objective] The aim was to study the influences and countermeasures of climate changes on the water resources in northwest.[Method] The influences of climate changes on water resources in northwest part were discussed... [Objective] The aim was to study the influences and countermeasures of climate changes on the water resources in northwest.[Method] The influences of climate changes on water resources in northwest part were discussed.Considering to the demand of water,corresponding countermeasures were proposed.[Result] Though there were distinct regional differences about the influences of climate changes on water resources in northwest part,the positive influences were larger than negative influences in general;because of large destruction of social factors,the positive effects of climate changes on water resources still can not solve the water shortage problem.In response,influences of climate changes on water resources shall be focused now and then.People’s awareness of saving water shall be improved.Hydraulic project shall be carried out.Suitable agricultural technology shall be applied to establish more sound laws and regulations.The ecological environment of northwest shall be improved and the development of the west part shall be promoted.[Conclusion] The study provided scientific basis for the construction of ecological environment and economic social development in the northwest. 展开更多
关键词 Climate change northwest area Water resources COUNTERMEASURE china
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ENVIRONMENTAL MIGRATION AND SUSTAINABLE DEVELOPMENT——A Case Study of Southwest China 被引量:1
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作者 王克林 《Chinese Geographical Science》 SCIE CSCD 1998年第3期80-89,共0页
This paper focuses on migration occurrence as a result of environmental degradation and population growth. It briefly reviews previous practices in some less developed courtries and then considers the extent to which ... This paper focuses on migration occurrence as a result of environmental degradation and population growth. It briefly reviews previous practices in some less developed courtries and then considers the extent to which environmental factors have been and may be significant in initiating migration. A case study of the karst region of southwest China is used to illustrate the phenomenon, including root causes, restrictive factors, nature of the migration, desires of migrants, strategies of response and optional policies. It is argued that a comprehensive approach to the prevention of environmentally caused displacement should be developed. 展开更多
关键词 ENVIRONMENTAL degradation MIGRATION SUSTAINABLE DEVELOPMENT KARST area SOUTHWEST china
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Research on the Harmonious Development of New Rural Communities under the Perspective of Balancing Urban and Rural Areas 被引量:2
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作者 ZHANG Jing 《Asian Agricultural Research》 2011年第7期39-42,共4页
On the basis of offering a definition of New Rural Communities (NRCs), the paper analyzes the values of New Rural Communities and argues that the construction of NRCs is able to contribute to the enhancement of the co... On the basis of offering a definition of New Rural Communities (NRCs), the paper analyzes the values of New Rural Communities and argues that the construction of NRCs is able to contribute to the enhancement of the comprehensive agricultural production capability as well as the development of social productivity. Meanwhile the incomes of the rural residents can be boosted, which denotes the realization of a harmonious society where the achievements of China's reform and development are shared by each citizen. Moreover, the construction of NRCs facilitates the economization of land use and thus improves the overall living standard of the residents, while helping to cut the administrative cost and promote democracy at the primary level. This paper also points out various problems arising during the construction of NRCS in China: blindly following suit in accordance with the modes of the urban communities; lack of funds, which leads to the absence of the supporting mechanisms of NRCs; vague positioning and the ensuing shortage of impetus for continued development. Finally, the paper raises the corresponding measures and suggestions: first, based on reality, make overall planning and scientific arrangement; second, the government should play the dominant role while respecting the principal position of the rural residents and introducing the market mechanism; third, increase science and technology input and attach equal importance to economic and social benefits; fourth, broaden fund-raising channels while completing the supervision mechanism. 展开更多
关键词 Balancing urban and rural areas New Rural Communities Harmonious development china
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COMPARISON OF THE STRUCTURAL CHARACTERISTICS OF DEVELOPED VERSUS UNDEVELOPED MID-LEVEL VORTEXES 被引量:1
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作者 黄辉军 袁金南 +1 位作者 李春晖 毛伟康 《Journal of Tropical Meteorology》 SCIE 2014年第1期57-65,共9页
Using the NCEP 1°×1°reanalysis data,several obvious differences of the structural characteristics of developed versus undeveloped mid-level vortexes are studied.First,the central vorticity of the develo... Using the NCEP 1°×1°reanalysis data,several obvious differences of the structural characteristics of developed versus undeveloped mid-level vortexes are studied.First,the central vorticity of the developed mid-level vortex increases towards higher levels while the undeveloped one decreases.The low-level convergence structure maintains well in the developed mid-level vortex whereas the undeveloped one does badly.Second,on the one hand,according to the symmetric analysis,the horizontal wind field and wind vertical section of the developed mid-level vortex are well symmetric while those of the undeveloped one are less symmetric.Meanwhile,weak wind vertical shear help the developed mid-level vortex to establish a warm core in upper-and mid-levels of the troposphere.On the other hand,according to the balance analysis,better balance between wind and pressure is shown in the mid-and lower-levels of the troposphere of the developed mid-level vortex than in those of the undeveloped vortex.Third,positive anomaly of potential vorticity is enhanced and developed in the vertical direction of the developed vortex.However,the undeveloped vortex weakens with a weak positive anomaly. 展开更多
关键词 South china Sea area tropical cyclone genesis and development mid-level vortex structural characteristics
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Exploration and development of continental tight oil in China 被引量:2
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作者 HU Suyun ZHU Rukai +3 位作者 WU Songtao BAI Bin YANG Zhi CUI Jingwei 《Petroleum Exploration and Development》 2018年第4期790-802,共13页
Based on the investigation of tight oil exploration and development in North America, the successful cases of tight oil exploration and development in North America are summarized. The geological differences between c... Based on the investigation of tight oil exploration and development in North America, the successful cases of tight oil exploration and development in North America are summarized. The geological differences between continental tight oil in China and marine tight oil in North America is analyzed to explore the technical strategies for the industrial development of continental tight oil in China. The experiences of large-scale exploration and profitable development of tight oil in North America can be taken as references from the following 6 perspectives, namely exploring new profitable strata in mature exploration areas, strengthening the economic evaluation of sweet spots and focusing on the investment for high-profitability sweet spots, optimizing the producing of tight oil reserves by means of repetitive fracturing and 3 D fracturing, optimizing drilling and completion technologies to reduce the cost, adopting commodity hedging to ensure the sustainable profit, and strengthening other resources exploration to improve the profit of whole project. In light of the high abundance of tight oil in China, we can draw on successful experience from North America, four suggestions are proposed in sight of the geological setting of China's lacustrine tight oil:(1) Evaluating the potential of tight oil resources and optimizing the strategic area for tight oil exploration;(2) selecting "sweet spot zone" and "sweet spot interval" accurately for precise and high efficient development;(3) adopting advanced tight oil fracturing technology to realize economic development;(4) innovating management system to promote the large-scale profitable development of tight oil. 展开更多
关键词 CONTINENTAL TIGHT OIL sweet-spot area sweet-spot interval profitable exploration and development china North AMERICA
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