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构建“区域关区”推进一体化进程中的海关定位与改革
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作者 张国强 《海关与经贸研究》 2014年第3期1-8,共8页
区域经济发展为海关管理体制和行为模式提出了新的更高的要求,在区域经济一体化的进程中,海关是否介入、如何介入,如何协调区域内政府、市场和企业的关系,加强海关自身科学化建设,已成为海关今后发展面临的突出问题。本文首次提出"... 区域经济发展为海关管理体制和行为模式提出了新的更高的要求,在区域经济一体化的进程中,海关是否介入、如何介入,如何协调区域内政府、市场和企业的关系,加强海关自身科学化建设,已成为海关今后发展面临的突出问题。本文首次提出"区域关区"的概念,对构建"区域关区"的必要性、思路、要求和存在问题等进行了较为周密的宏观研究,并对区域经济一体化进程中的海关定位与改革进行了探索。 展开更多
关键词 区域经济 区域外贸 区域关区 改革
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Revealing Storage-area Relationship of Open Water in Ungauged Subalpine Wetland-Napahai in Northwest Yunnan, China 被引量:7
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作者 LI Jie HU Jin-ming +4 位作者 DENG Wei HUANG Sheng-li JIA Hai-feng ZHU Chun-ling LUO Huai-xiu 《Journal of Mountain Science》 SCIE CSCD 2013年第4期553-563,共11页
Mountains and plateaus in Southwest China contain many subalpine and alpine wetlands, with signifieant hydroecological functions. But ungauged or poorly gauged eonditions limit the study and understanding of hydrologi... Mountains and plateaus in Southwest China contain many subalpine and alpine wetlands, with signifieant hydroecological functions. But ungauged or poorly gauged eonditions limit the study and understanding of hydrological regimes of these wetland types. This study selects an ungauged subalpine wetland - Napahai in Northwest Yunnan, China - as a case for developing a practical approach to revealing its storage-area relationship of open water. A Trimble R8 GNSS (Global Navigation Satellites Systems) RTK (Real-time Kinematic system) and sonar fathometer were used to survey fine- resolution elevation data and generate a digital elevation model of the Napahai Wetland. Forty-four Landsat images from 1987 to 2Oll were collected, and the Normalized Difference Water Index was used to classify open water features in the area. The area of open water in Napahai was ealculated for each phase. With these data and a developed conceptual model, the storage of open water for each phase was estimated using ArcGIS tools. Both storage and area of open water showed significant intra-annual and inter-annual variations. In the rainy season, the monthly change of average storage of open water in Napahai showed about 1-2 months lag behind mean monthly rainfall. The storage-area relationship of open water was well fit by a power function equation (R2=0.91, n=44). This study indicates that if detailedelevations are available for similarly ungauged subalpine wetlands in Southwest China, researchers can use this practical approach to estimate multi- temporal areas and storages and reveal the storage- area relationship of open water in the wetlands. The study provided valuable information of this ease wetland for optimizing its hydro-ecological managements and a new method to wetland researchers and managers for the hydrological study of similarly ungauged wetland complex. 展开更多
关键词 Water storage Ungauged wetland Napahai Wetland Normalized Difference WaterIndex
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Exploring relations between city regions based on mobile phone data
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作者 汪烁枫 李志恒 +1 位作者 姜山 谢娜 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1799-1806,共8页
City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations b... City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations between regions of Shanghai based on mobile phone data is explored. By formulating the regions as nodes in a network and the commuting between each pair of regions as link weights, the distribution of nodes degree, and spatial structures of communities in this relation network are studied. Statistics show that regions locate in urban centers and traffic hubs have significantly larger degrees. Moreover, two kinds of spatial structures of communities are found. In most communities, nodes are spatially neighboring. However, in the communities that cover traffic hubs, nodes often locate along corridors. 展开更多
关键词 mobile phone data city relations community DEGREE
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Spatial Autocorrelation Analysis on Regional Economic Disparity of Northeast Economic Region in China 被引量:6
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作者 Li Fei Zhou Chenghu 《Chinese Journal of Population,Resources and Environment》 2009年第2期27-31,共5页
Popular regional inequality indexes such as variation coefficient and Gini coefficient can only reveal overall inequality, and have limited ability in revealing spatial dependence or spatial agglomeration. Recently so... Popular regional inequality indexes such as variation coefficient and Gini coefficient can only reveal overall inequality, and have limited ability in revealing spatial dependence or spatial agglomeration. Recently some methods of exploratory spatial data analysis such as spatial autocorrelation have provided effective tools to analyze spatial agglomeration and cluster, which can reveal the pattern of regional inequality. This article attempts to use spatial autocorrelation at county level to get refined spatial pattern of regional disparity in Chinese northeast economic region over 2000-2006 (2001 absent). The result indicates that the basic trend of regional economy is an increasing concentration of growth among counties in northeast economic region, and there are two geographical clusters of poorer counties including the counties in western Liaoning Province and adjacent counties in Inner Mongolia, poorer counties of Heihe, Qiqihar and Suihua in Heilongjiang Province. This article also reveals that we can use the methods of exploratory spatial data analysis as the supplementary analysis methods in regional economic analysis. 展开更多
关键词 regional disparity spatial analysis northeast economic region spatial autocorrelation
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Spatial Correlation and Ecological Characteristics Analysis of Man-agement Area for Biodiversity Conservation and Relevant Regionalization 被引量:5
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作者 WANG Wenjie ZHENG Hua +5 位作者 XU Chao JIANG Weiguo DU Yunhui WANG Wei ZHANG Zhe LIU Xiaofu 《Chinese Geographical Science》 SCIE CSCD 2014年第1期71-82,共12页
Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in... Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in China.In order to clarify the interrelation among key ecological zone plans,this paper carried out the research on spatial relation of priority areas of biodiversity conservation and three key ecological areas(key ecological function areas,key regions of ecological service function,national nature reserves)and the research on ecological conditions,based on multi-scale ecological spatial theme information,which incorporates elements like ecological quality and type,and by the aid of spatial information analysis and GIS modeling.The results showed a contrastively fine spatial consistency with 68.8%of priority areas of biodiversity conservation overlapping with three key ecological areas.Although the environment in priority areas of biodiversity conservation were in good conditions,protection pressure is also increasing,powerful supervision and protection should not be ignored.The environmental conditions in the overlapping areas,as a whole,were superior to those in the non-overlapping areas.Since two areas have different characteristics,targeted protection measures should be formulated based on this difference,which will be very important for biodiversity conservation in priority areas of biodiversity conservation. 展开更多
关键词 biodiversity conservation ecological regionalization ecological pressure ecological service spatial correlation analysis
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Species-area relationship within and across functional groups at alpine grasslands on the northern Tibetan Plateau,China 被引量:1
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作者 ZHOU Nan WU Jian-shuang +2 位作者 SHEN Zhen-xi ZHANG Xian-zhou YANG Peng-wan 《Journal of Mountain Science》 SCIE CSCD 2016年第2期265-275,共11页
The species-area relationship (SAR) is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for differ... The species-area relationship (SAR) is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for different alpine grassland types on the Tibetan Plateau, China. We explored whether the plant composition of different functional groups affects the manner in which species richness inereases with increasing area at scales ≤ 1.0 m^2. We also compared species richness (S) within and across forbs, legumes, sedges and grasses, with sampling subplot area (A) increasing from 0.0625 m^2 to 1.0 m^2 between alpine meadow and steppe communities. We applied a logarithmic function (S = b0 + b1 ln A) to determine the slope and intercept of SAR curves within and across functional groups. The results showed that the logarithmic relationship holds true between species richness and sampling area at these small scales. Both the intercept and slope of the logarithmic forbs-area curves are significantly higher than those for the three other functional groups (P 〈 0.05). Forb accounts for about 91.9 % of the variation in the intercept and 75.0% of the variation in the slope of the SAR curve when all functional groups' data were pooled together. Our results indicated that the different SAR patterns should be linked with species dispersal capabilities, environmental filtering, and life form composition within alpine grassland communities. Further studies on the relationship between species diversity and ecosystem functions should specify the differential responses of different functional groups to variations in climate and anthropogenic disturbances. 展开更多
关键词 Changtang Nature Reserve Complementary response Plant functional groups Plant life forms Species coexistence
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Increasing trend of lightning activity in the South Asia region 被引量:3
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作者 Kai Qie Xiushu Qie Wenshou Tian 《Science Bulletin》 SCIE EI CSCD 2021年第1期78-84,M0004,共8页
Lightning is an important natural source of wildfires and oxynitride,and hence significantly influences ecological systems and atmospheric chemistry.Here,we choose South Asia,an important region for global water reall... Lightning is an important natural source of wildfires and oxynitride,and hence significantly influences ecological systems and atmospheric chemistry.Here,we choose South Asia,an important region for global water reallocation and global climate changes,to examine lightning variations based on the longest existing lightning dataset from the OTD/LIS observations.We identify a clear increase in lightning density in the research region,increasing at a rate of 0.096 fl km^(-2)a^(-1)over the last two decades.Multiple linear regression analysis is adopted to identify the main influencing factors among ten potential thermodynamic or microphysical factors and the crucial areas contributing to the increases in lightning.The surface latent heat flux along the west coast of the Indian subcontinent is the largest contributor,explaining52%of the lightning variance and contributing to a 0.025 fl km^(-2)a^(-1)increase.The sea surface temperature in the Arabian Sea,the convective available potential energy(CAPE)over the northwestern Indian subcontinent,and the wind shear along the northwestern coast also make important contributions to the lightning increase,indicating that the thermodynamic effects overwhelm the microphysical effects on lightning activity over the South Asia region. 展开更多
关键词 Lightning activity TREND South Asian monsoon region Thermodynamic and microphysical factors Multiple linear regression analysis
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