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Intellectual Property Protection and New Development Pattern Construction of Xinjiang Jujube 被引量:2
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作者 Miaomiao XU Yulan BAI +3 位作者 Jinjin WANG Yuanpeng SUN Jin ZENG Zhiguo SUN 《Asian Agricultural Research》 2023年第7期1-8,共8页
"Three new developments"is the guiding ideology of Chinese-style high-quality development in the new era.Jujube(Zizyphus jujube Mill.)is a plant of Zizyphus of Rhamnaceae,which originated in China and has be... "Three new developments"is the guiding ideology of Chinese-style high-quality development in the new era.Jujube(Zizyphus jujube Mill.)is a plant of Zizyphus of Rhamnaceae,which originated in China and has been listed as one of the"five fruits"since ancient times.Xinjiang is the most important jujube producing area in China,and its yield has accounted for 50%of the national jujube yield.In the five prefectures and cities of southern Xinjiang,as well as the regimental farms of southern and eastern Xinjiang of Xinjiang Production and Construction Corps,the jujube industry is an advantageous characteristic industry in agriculture.This paper studied Xinjiang jujube industry and its agricultural intellectual property resources,analyzed six major issues to be further implemented,such as the"three new developments"thinking and the strategy of building an intellectual property power,and puts forward eight strategies such as coordinating the two markets and two resources to accelerate the construction of a new development pattern and dual circulation of jujube. 展开更多
关键词 Jujube(Zizyphus jujube Mill.) FRUIT Intellectual property New development pattern XINJIANG
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Classification and Spatial Pattern of Township Development in Liaoning Province, China
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作者 LIU Xiaohui ZHENG Xingming +1 位作者 LIU Wenxin CHEN Xinyu 《Chinese Geographical Science》 SCIE CSCD 2023年第4期708-718,共11页
The classification of township development types is an urgent problem that requires solution to enable the township to choose an appropriate development path.Using a township development classification method,we deter... The classification of township development types is an urgent problem that requires solution to enable the township to choose an appropriate development path.Using a township development classification method,we determine the township development types and their spatial patterns in Liaoning Province,China.The results showed that the patterns of township development types based on their general advantages had significant spatial differentiations.The planting,and livestock and poultry breeding township development types based on general advantages were mainly distributed across the central plain of Liaoning Province,China,and also concentrated in Dandong City−Dalian City along Yellow Sea coast,and in the northwest of Chaoyang City.The business and tourism,industry and mining,and residence township development types based on general advantages were distributed mainly along the Shenyang–Dalian Economic Belt in the central and southern Liaoning Province.The ecology township development type based on general advantages was mainly distributed in the eastern and western Liaoning Province to maintain regional ecological security.Township development types based on non-advantages were sporadically distributed in the middle and western Liaoning Province.Based on the classification and spatial patterns,the differences between the distribution of twonship development types and the plan for the major functional areas of Liaoning Province were proposed which could provide the basis for the optimization of the major functional areas. 展开更多
关键词 general advantage township development type spatial pattern Liaoning Province China
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Fuzzy pattern recognition model of geological sweetspot for coalbed methane development
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作者 LIU Gaofeng LIU Huan +3 位作者 XIAN Baoan GAO Deli WANG Xiaoming ZHANG Zhen 《Petroleum Exploration and Development》 SCIE 2023年第4期924-933,共10页
From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development a... From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development are determined, and the evaluation index system of geological sweetspot for CBM development is established. On this basis, the fuzzy pattern recognition(FPR) model of geological sweetspot for CBM development is built. The model is applied to evaluate four units of No.3 Coal Seam in the Fanzhuang Block, southern Qinshui Basin, China. The evaluation results are consistent with the actual development effect and the existing research results, which verifies the rationality and reliability of the FPR model. The research shows that the proposed FPR model of geological sweetspot for CBM development does not involve parameter weighting which leads to uncertainties in the results of the conventional models such as analytic hierarchy process and multi-level fuzzy synthesis judgment, and features a simple computation without the construction of multi-level judgment matrix. The FPR model provides reliable results to support the efficient development of CBM. 展开更多
关键词 coalbed methane development geological sweetspot evaluation index system analytic hierarchy process multi-level fuzzy synthesis judgment fuzzy pattern recognition
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Spatio-temporal Pattern Characteristics of Relationship Between Urbanization and Economic Development at County Level in China 被引量:8
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作者 YANG Zhen ZHANG Xiaolei +2 位作者 LEI Jun DUAN Zuliang LI Jiangang 《Chinese Geographical Science》 SCIE CSCD 2019年第4期553-567,共15页
The relationship between China’s urbanization and economic development(RCUED) is an important concern nationwide. As important actors in regional strategy and policy, county-level regions have played an increasingly ... The relationship between China’s urbanization and economic development(RCUED) is an important concern nationwide. As important actors in regional strategy and policy, county-level regions have played an increasingly significant role in the development of China’s social economy. However, the existing research on the RCUED lacks the fine depiction of the county-level administrative units.Using 2000 and 2010 census data and the statistical analysis method, we uncovered the evolution characteristics of China’s urbanization and economic development and conducted a quantitative identification for the RCUED with improved methods using the quadrant map approach. In addition, we investigated the spatial correlation effect of the RCUED using the spatial autocorrelation analysis method. The results were as follows: 1) In general, a high degree of matching exists between China’s urbanization and economic development at the county level at the significance level of 0.01. The correlation coefficients between China’s urbanization and economic development in2000 and 2010 were 0.608 and 0.603, respectively. 2) A significant regional difference exists in the RCUED at the county level. Based on a comparative analysis of 2276 county units in China in the two years, we found that county units can be categorized as under-urbanized, basic coordination and over-urbanized in various areas. No situation was observed where urbanization seriously lagged behind the economic development level, so the levels of urbanization and economic development appear to be basically coordinated,and the coordination state may be gradually optimized over time. 3) Over time, the spatial dependency of the RCUED has weakened and the spatial heterogeneity has increased. Northeast China has always been an area characterized by over-urbanization. The number of county units classified as under-urbanized has begun to decline in eastern coastal urban agglomeration areas, while counties rich in resources have transformed from having point-shaped over-urbanization to plane-shaped under-urbanization along the northern border,and the number of over-urbanized county units has increased in the middle reaches of the Yangtze River. 4)’Lag-lag’ type and ’advance-advance’ type accounted for 68% of all counties in China, and these counties were shown to have obvious spatial differentiation characteristics. 展开更多
关键词 URBANIZATION ECONOMIC development RELATIONSHIP spatial-temporal pattern COUNTY China
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An overview of efficient development practices at low permeability sandstone reservoirs in China 被引量:1
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作者 Bingyu Ji Jichao Fang 《Energy Geoscience》 2023年第3期149-157,共9页
Low permeability sandstone reservoirs in China typically have more complicated geological conditions, pore structures, and flow characteristics as compared to medium-to-high-permeability sandstone reservoirs. Traditio... Low permeability sandstone reservoirs in China typically have more complicated geological conditions, pore structures, and flow characteristics as compared to medium-to-high-permeability sandstone reservoirs. Traditional geological and seepage theories, and engineering methods are not applicable to the development of these low permeability reservoirs, and wells drilled into them often produce oil and gas at very low rates. Recent breakthroughs in reservoir exploitation technology have greatly improved the productivity of low permeability reservoirs, making them the primary target for oil exploration and extraction in China. The development theories and practices applied to low permeability reservoirs in China are reviewed in this study— based on relevant geological and engineering practices, including drilling, fracturing, recovery, and surface engineering. A unique series of technological advances that aid the development of low permeability reservoirs in China are summarized here. This study may serve as a meaningful guide in achieving scale efficiency for the development of low permeability reservoirs. 展开更多
关键词 Well pattern FRACTURING development model Reservoir description Low permeability reservoir
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The temporal and spatial patterns and potential evaluation of China's energy resources development 被引量:8
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作者 MA Beibei LU Chunxia +1 位作者 ZHANG Lei CHENG Xiaoling 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期347-356,共10页
The issue of China's energy supply security is not only the key problem which af- fects China's rapid and sustainable development in the 21st century, but also the one which international attention focuses on. Based... The issue of China's energy supply security is not only the key problem which af- fects China's rapid and sustainable development in the 21st century, but also the one which international attention focuses on. Based on the notable characteristic of spatial imbalance between energy production and consumption in China, this paper takes the evolution of China's primary energy resources development(excluding hydropower) from 1949 to 2007 as the study object, with the aim to sum up the evolutive characteristics and laws of China's energy resources development in the past nearly 60 years. Then, based on comprehensive considerations of coal's, oil's and natural gas's basic reserves, qualities, geological conditions production status, and ecological service function of every province, this paper adopts development potential index (DP)to evaluate the development potential of every province's en- ergy resources, and divide them into different ranks. Conclusions are drawn as follows: (1) Generally speaking, China's gross energy production was increasing in waves from 1949 to 2007. From the viewpoint of spatial patterns, China's energy resources development has shown a characteristic of "concentrating to the north and central areas, and evolving from linear-shaped to "T-shaped" pattern gradually since 1949. (2) The structure evolution of China's energy resources development in general has shown a trend of "coal proportion is dominant but decreasing, while oil and gas proportions are increasing" since 1949. (3) At the provincial scale, China's energy resources development potential could be divided into large, sub-large, general and small ranks, four in all. In the future, the spatial pattern of China's energy production will evolve from "T-shaped" to "R-shaped pattern". These conclusions will help to clarify the temporal and spatial characteristics and laws of China's energy resources development, and will be beneficial for China to design scientific and rational energy development strategies and plans, coordinate spatial imbalance of energy production and consumption, ensure national energy supply, avoid energy resources waste and disorderly development, and promote regional sustainable development under the globalization back-ground with changeful international energy market. 展开更多
关键词 energy resources development temporal and spatial patterns potential evaluation China
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Methods to evaluate the impacts of physio- geographical pattern on spatio-temporal disparity of regional development 被引量:2
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作者 LI Guosheng GUO Zhaocheng LIAO Heping 《Journal of Geographical Sciences》 SCIE CSCD 2008年第2期225-236,共12页
With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic... With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic geography, and also has been the task for Chinese government to handle. Nevertheless, to quantitatively assess the impacts of physio-geographical patterns (PGP) on the regional development disparity has been ignored for a long time. In this paper, a quantitative method was adopted to assess the marginal effects of the PGP on spatio-temporal disparity using the partial determination coefficients. The paper described the construction of the evaluation model step by step following its key scientific thinking. Total GDP, per capita GDP, primary industrial output value and secondary industrial output value were employed in this study as the indicators to reflect the impacts of PGP on the regional development disparity. Based on the evaluation methods built by researchers, this study firstly analyzed the temporal impacts of the PGP on spatio-temporal disparity of the regional development in China during the past 50 years, and then explained the spatial differences at each development stage. The results show that the spatio-temporal disparity in China is highly related to the PGP, and that the marginal contribution rate could be employed as an effective way to quantitatively assess the impact of the PGP on spatio-temporal disparity of the regional development. 展开更多
关键词 physio-geographical pattern regional development spatio-temporal disparity marginal contribution rate
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Integrative analysis of the inverse expression patterns in pancreas development and cancer progression 被引量:1
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作者 Hong-Liang Zang Guo-Min Huang +1 位作者 Hai-Ying Ju Xiao-Feng Tia 《World Journal of Gastroenterology》 SCIE CAS 2019年第32期4727-4738,共12页
BACKGROUND As the malignant tumor,pancreatic cancer with a meager 5-years survival rate has been widely concerning.However,the molecular mechanisms that result in malignant transformation of pancreatic cells remain el... BACKGROUND As the malignant tumor,pancreatic cancer with a meager 5-years survival rate has been widely concerning.However,the molecular mechanisms that result in malignant transformation of pancreatic cells remain elusive.AIM To investigate the gene expression profiles in normal or malignant transformed pancreas development.METHODS MaSigPro and ANOVA were performed on two pancreas development datasets downloaded from the Gene Expression Omnibus database.Six pancreatic cancer datasets collected from TCGA database were used to establish differentially expressed genes related to pancreas development and pancreatic cancer.Moreover,gene clusters with highly similar interpretation patterns between pancreas development and pancreatic cancer progression were established by self-organizing map and singular value decomposition.Additionally,the hypergeometric test was performed to compare the corresponding interpretation patterns.Abnormal regions of metabolic pathway were analyzed using the Subpathway-GM method.RESULTS This study established the continuously upregulated and downregulated genes at different stages in pancreas development and progression of pancreatic cancer.Through analysis of the differentially expressed genes,we established the inverse and consistent direction development-cancer pattern associations.Based on the application of the Subpathway-GM analysis,we established 17 significant metabolic sub-pathways that were closely associated with pancreatic cancer.Of note,the most significant metabolites sub-pathway was related to glycerophospholipid metabolism.CONCLUSION The inverse and consistent direction development-cancer pattern associations were established.There was a significant correlation in the inverse patterns,but not consistent direction patterns. 展开更多
关键词 PANCREATIC CANCER PANCREAS development INVERSE pattern METABOLITES subpathway
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Economic reform, open-door policy and changes in spatial development patterns in China 被引量:1
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作者 WANG Enru1, LU Xiang-xing2 (1.Department of Geography University of Washington Smith Hall, Box 353550 Seattle, WA 98195, USA 2. Department of Geography Kansas State University Manhattan, KS 66506, USA) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第4期7-19,共13页
The study profiles and explains the significant changes that have taken place in China's spatial development patterns since the inception of its economic reform and opening two decades ago. Principal component an... The study profiles and explains the significant changes that have taken place in China's spatial development patterns since the inception of its economic reform and opening two decades ago. Principal component analysis is used to delineate spatial patterns. The analyses show that prior to the reform China's spatial development pattern was characterized by the dominance of the three municipalities and the Northeast, as well as by both the coast-interior and the north-south disparities. Northern provinces were generally more industrialized and economically powerful than the southern ones. After two decades of reform, regional development has become multi-centered with South China, the Yangtze Delta and the Beijing-Tianjin area being the three most important regions of the country. The coastal provinces as a whole rose to prominence on China's economic map while the Northeast has diminished its clout. The coast-interior gap not only remains but may have widened. The north-south disparity also still exists but there has been a role reversal with the south now in the lead position. Virtually all inland provinces now find themselves at or near the low end of the development spectrum. We argue that the major reason for the recent shifts in Chinese space economy is the spatially differentiated economic growth resulted from the reform and open door policy and from the new, uneven development strategy adopted by the Chinese government. The paper discusses four specific factors that have reshaped China's spatial development patterns. 展开更多
关键词 regional development pattern differentiated growth economic reform open door policy
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Relationship between Different Pronuclear Patterns and Potential of Embryo Development and Pregnancy 被引量:1
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作者 Zhong-mei LI, Yu-bao WANG, Dun-yu GU, Xiao-yun WU, De-qi JIANG, Zhen LU, Zuan-chong FENGInfertility and IVF Center of Shanghai Institute of Planned Parenthood Research, Shanghai , 200032, China 《Journal of Reproduction and Contraception》 CAS 2003年第2期99-104,共6页
Objective To explore the relationship between the patterns of pronucleus and embryo development and pregnancy potential in the pronuclear stageMethods According to the number and distribution of nucleolar precursor bo... Objective To explore the relationship between the patterns of pronucleus and embryo development and pregnancy potential in the pronuclear stageMethods According to the number and distribution of nucleolar precursor bodies, the embryos at pronuclear stage were classified into 6 pronuclear patterns from 0 to 5, 16 - 18 h after in vitro fertilization (IV F) or intracytoplasmic sperm injection (ICSI). For each, pattern, the subsequent embryonic morphology and the pregnancy rate were analyzed.Results Embryos of Pattern 0 developed to significantly more embryos with good quality and higher pregnancy potential than the embryos developing from other patterns (83. 14% and 76. 11% respectively, P<0. 05). The pregnancy rate was decreased as less embryos of Pattern 0 were transferred . The pregnancy rate of the groups of only Pattern 0, with Pattern 0, and without Pattern 0 were 48. 08% , 32. 14% and 21. 28% respectively (P<0. 05).Conclusions The pronuclear patterns are of the predictive value of embryo development and pregnancy potential, which can be used as a new tool for the selection of embryos in IVF and ICSI. 展开更多
关键词 pronuclear pattern embryo selection IVF embryo development
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Evolution of Temporal-spatial Pattern of Green Development Efficiency in Shandong Province 被引量:1
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作者 Hou Ailing Guo Fuyou 《Meteorological and Environmental Research》 CAS 2019年第3期74-76,共3页
Temporal-spatial differentiation characteristics of green development efficiency in 17 prefecture-level cities of Shandong Province during 2005-2016 were studied by using SBM-undesirable model and spatial auto-correla... Temporal-spatial differentiation characteristics of green development efficiency in 17 prefecture-level cities of Shandong Province during 2005-2016 were studied by using SBM-undesirable model and spatial auto-correlation analysis.Results showed that ① green development efficiency considering unexpected output could more accurately represent the real cost of regional development,while lower green development efficiency considering unexpected output and traditional green development efficiency illustrated that Shandong Province has spent a lot of resources and environment in the long-term development process.② Green development efficiency of Shandong Province during 2005-2016 showed the change characteristics of "peak-valley-peak-valley",and standard deviation and coefficient of variation of green development efficiency showed fluctuation characteristics in the research period.③ Green development efficiency of Shandong Province had obvious spatial differentiation characteristics,and its polarization differentiation was obvious. 展开更多
关键词 Green development EFFICIENCY Performance measurement Temporal-spatial pattern SHANDONG PROVINCE
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The Airport Economy Development of ZAEZ's Innovation on the Regional Development Pattern 被引量:1
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作者 Zhang Zhancang Chen Ping Peng Junjie 《Contemporary Social Sciences》 2016年第1期80-95,共16页
Regional economic development can be enhanced through the development of an airport economy that includes: changing the regional elements endowment at the micro scale, coupling with regional industries at the medium s... Regional economic development can be enhanced through the development of an airport economy that includes: changing the regional elements endowment at the micro scale, coupling with regional industries at the medium scale, and accelerating tax revenues and employment growth at the macro scale. As a representative example of the Chinese airport economy, the Zhengzhou Airport Economic Zone(ZAEZ) has played a significant leading and demonstrating role in the following fields: deepening the system reforms in an all-round way, promoting the "synchronization of five modernizations", building "one carrier and four systems", constructing "Four Henan", advancing the structural reform of supply-side and integrating the resources of the Henan airport. This article concludes: The supply-side structural reform needs to be accelerated and integrated into the international frontiers under "the Belt and Road" initiative. The ZAEA development has promoted the innovation of regional development patterns and showed the tendency toward the "five modernizations" of future regional development. The airport economy has developed rapidly based on the international aviation transportation system, and may change the traditional development patterns of regional centers located in coastal areas, and open a new era of regional development in the inland regions. 展开更多
关键词 AIRPORT ECONOMY the structural REFORM of supply-side Zhengzhou AIRPORT Economic Zone REGIONAL development pattern INLAND era
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Spatial Pattern Evolution and Industrial Characteristics of Economic and Technological Development Zones and High-tech Industrial Zones in China 被引量:1
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作者 LI Jingxian LIU Qing LI Guicai 《Journal of Landscape Research》 2021年第2期11-16,共6页
Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of na... Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of national and provincial economic and technological development zones and high-tech industrial zones in China were collected and arranged.Kernel density analysis and other GIS spatial analysis techniques were used to analyze the evolution laws of spatial patterns of economic and technological development zones and high-tech industrial zones in cities from 2006 to 2018.First,the agglomeration intensity was compared by measuring the degree of regional agglomeration and dispersion on the two time nodes.Next,kernel density method was used to explore the evolution of the two in the spatial layout and location,and analyze development commonness and difference of economic and technological development zones and high-tech industrial zones.Finally,the trend and reason of spatial evolution of development zones with different leading industries were explored.Research results show that:①the agglomeration degree of layout of high-tech industrial zones is stronger than that of economic and technological development zones,and there are similarities and differences in distribution trend of spatial patterns of the two types of development zones;②the distribution of labor-intensive,capital-intensive and technology-intensive development zones is concentrated at smaller scales and dispersed at larger ones;③although there are differences between the economic and technological development zones and the high-tech industrial zones in the goal,support,structure and function,management system and so on,their spatial development presents a trend of convergence.In the future,when enhancing urban-rural planning and public administration,governments should combine the trend of industrial transformation and upgrading,and optimize spatial layout of development zones by adjusting industrial structure,layout,transportation and land use. 展开更多
关键词 Economic and technological development zone High-tech industrial zone Spatial pattern
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NEW DEVELOPMENT PATTERN AND COORDINATION WITH ENVIRONMENT FOR GREAT SHANGHAI
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作者 姚士谋 帅江平 侯晓虹 《Chinese Geographical Science》 SCIE CSCD 1993年第3期24-35,共12页
The urban construction of Shanghai will come into a new area since China has deciared to exploit and open Pudong. Based on the analysis on economic development of China and the world, the developmental strategy for Sh... The urban construction of Shanghai will come into a new area since China has deciared to exploit and open Pudong. Based on the analysis on economic development of China and the world, the developmental strategy for Shanghai should take the following contents into consideration: 1) Shanghai should be built into one of the most important intemational and modern supercity in Asian-Pacifie Region. 2) Shanghai should keep the position of the largest economic center of China and important port city for international trade. 3) Shanghai should be taken as growth pole of the Changjiang River Delta. According to the considderations mentioned above, the spatial distribution patten and the management of environment are discassed. 展开更多
关键词 developmentAL strategy development pattern ENVIRONMENT management SHANGHAI
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NEW PATTERNS OF URBAN DEVELOPMENT IN CHINA
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作者 Zhen-guo Zhu Shi-mou Yao 《Chinese Geographical Science》 SCIE CSCD 2000年第1期21-30,共10页
According to the basic features of socio economic development in China, the paper retrospects the developmental process of Chinese cities in the 20th century. Based on lots of data and related research achievements, f... According to the basic features of socio economic development in China, the paper retrospects the developmental process of Chinese cities in the 20th century. Based on lots of data and related research achievements, five new patterns of Chinese urban development are pointed out, that is 1) regional disparity of urban development in China is still obvious and large; 2) cities in developed region develop in the form of agglomeration and coordination; 3) spatial layout shape of Chinese cities appears relatively tight, and there exists great outside expansion inclination; 4) the construction of exploitation zone becomes the new important factor of urban development in the 1990s; 5) number increase of cities at county level become the main tide of urban development, but cause the discrete understanding for the concept of urban substantial region, which construct a challenge to urban management. In the end the article puts forward a series thoughts on the future trends and countermeasures of urban development in China. 展开更多
关键词 new patternS URBAN development URBAN GROUP URBAN SCALE system
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Sustainable development pattern and the strategy in the Three Gorges Reservoir Areas 被引量:3
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作者 WuG WeiJ 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第1期83-87,共5页
The development pattern, development situation, and existing problems of land exploitation in Zigui County, Three Gorges Reservoir Areas of China were presented. The sustainable development mode and its strategy in th... The development pattern, development situation, and existing problems of land exploitation in Zigui County, Three Gorges Reservoir Areas of China were presented. The sustainable development mode and its strategy in the Three Gorges Reservoir Areas was also discussed. A sustainable development framework for low mountain regions, middle mountain regions and high mountain regions was developed, and management countermeasures for structural optimization of complex ecosystems were advanced. 展开更多
关键词 可持续发展模型 策略 秭归县 三峡库区
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Stand development patterns of forest cover types in the natural forests of northern Baekdudaegan in South Korea
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作者 Ji Hong Kim Guangze Jin Sang Hoon Chung 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第2期381-390,共10页
The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest ... The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest communities were aggregated into eight forest cover types by species composition in the overstory of each forest community.The forest cover types were of mixed mesophytic,‘‘others’ ’ deciduous,Quercus mongolica dominant,Q.mongolica pure,Pinus densiflora–Q.mongolica,P.densiflora,Betula ermanii,and Q.mongolica–P.koraiensis.The ecological information was organized by importance value and species diversity for each forest type.Based on the correlation between species diversity index and the abundance of Q.mongolica plus P.densiflora for corresponding forest cover types,we compared the developmental process and approximate successional pathway between each cover type.The P.densiflora forest cover type changes into the P.densiflora–Q.mongolica cover type,followed by the Q.mongolica dominant cover type through continuous invasion of the oak trees.Furthermore,the Q.mongolica pure cover type would spread toward the Q.mongolica dominant cover type with a mixture of various deciduous tree species.The Q.mongolica dominant cover type progresses through the other deciduous cover types to the mixed mesophytic cover type with diversified composition and structure.On the mid to lower slopes,with loamy soils and good moisture conditions,various deciduous forest types should progress,by ecological succession,toward the mixed mesophytic cover type without any further disturbance. 展开更多
关键词 Baekdudaegan Forest cover type Species composition Species diversity Stand development patternS
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Exploiting pattern and sustainable development of marginal lands in the Three Gorge Reservoir Areas
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作者 WU Gang, LI Jing, KONG Hong mei, ZHAO Jing zhu, GAO Lin (Department of Ecology System, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期173-179,共7页
This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been po... This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been pointed that problems of the soil fertility degradation, poor productivity in crop lands, natural disasters and environmental deterioration existed in all the exploited marginal lands. In order to maintain the sustainability of the marginal lands, following measure have been proposed: prohibiting cultivation in the crop lands with a slope more than 25°, restoring vegetation in the slope more than 25°, strengthening the basic agricultural construction, establishing the production base of woody feeds and oils, establishing a multi dimensional management model with reasonable structure and optimum function for forestry, agriculture and fishing. 展开更多
关键词 marginal lands utilization pattern sustainable development Three Gorge Reservoir Are4
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Present land use and cover patterns and their development potential in North Ningxia
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作者 WUWeicheng ZHANGWenfeng 《Journal of Geographical Sciences》 SCIE CSCD 2003年第1期54-62,共9页
With the objectives to acquire the fundamental dat a of the territorial resource, understand the impacts of human activit ies on the land use and cover patterns and evaluate the potential of the future exploitation, a... With the objectives to acquire the fundamental dat a of the territorial resource, understand the impacts of human activit ies on the land use and cover patterns and evaluate the potential of the future exploitation, an intensive land cover classification with an accuracy of 93% has been completed for North Ningxia by remote sen sing technique based on the adoption of a combination method composed o f texture training, maximum likelihood classification and post-processing such as re-allocation and aggregation. This classification result was incorporated with the contemporaneous socio-economic and meteorological d ata for cross-sectional regression modelling to reveal the spatial dete rminants of the land cover patterns and understand the human-environmen tal relationships. A tentative evaluation on the potential of soil exp loitation in the near future was carried out in combination with our land use and cover change detection results aiming at supplying some useful references for the central and local governments in their sustainable l and use planning. 展开更多
关键词 land use and cover patterns human-environment relationship development potential North Ningxia cross-sectional analysis spatial determinant
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Spatial and Temporal Pattern of Urban Smart Development in China and Its Driving Mechanism 被引量:3
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作者 CHEN Xiaohong WEI Luyao ZHANG Haifeng 《Chinese Geographical Science》 SCIE CSCD 2018年第4期584-599,共16页
Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly ... Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly in forming scientific and sustainable development concept and responding to new normal strategic opportunities. Based on statistic data of 294 prefecture-level cities and above in China from 2000 to 2015, we analyzed spatial and temporal evolution of urban smart development in China by constructing a dynamic fitting model of urban land expansion, population growth, and economic development as well as the coefficient of variation of urban smart development(CVSD). Further efforts were then made to consider differential distribution regularity of urban smart development so as to understand the driving mechanisms of heterogeneous classification of urban smart development in China from different scales and scale variation. Our results indicate that: 1) the disordered growth tendency of urban cities in China is overall well controlled in the middle, and late research and it mainly presented a doublet coexistence of shrinkage disordered cities and smart developing cities. It is particularly obvious that Northeast China and East China have regarded shrinkage disordered cities and smart developing cities as main development tendency separately. 2) Areas with basic stability and relative variation were relatively dispersed across the time period, but the proportion was far beyond areas with significant variation. It demonstrates a relative equilibrium spatial and temporal differential evolution pattern of prefecture-level cities and above in China, except for Tongling, Lanzhou and Chaoyang. 3) prefecture-level cities and above in China are mostly characterized by shrinkage disordered and smart development classification under the background of different scale and scale variation from 2000–2015; however, the spatial resonance relation is not obvious. 4) There are many interaction factors forming an important driving mechanism in developing the spatial and temporal pattern of urban smart development in China, including natural geographical factors, industrial structure adjustment, human capital radiation, regional traffic accessibility, and government decision-making intervention. 展开更多
关键词 发展中城市 经济开发 中国 空间 时间 机制 开车 自然地理因素
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