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Topological relations between spherical spatial regions with holes 被引量:1
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作者 Jingwei Shen Lan Zhang Min Chen 《International Journal of Digital Earth》 SCIE 2020年第4期429-456,共28页
There is growing interest in globally modelling the entire planet.Although topological relations between spherical simple regions and topological relations between regions with holes in the plane have been investigate... There is growing interest in globally modelling the entire planet.Although topological relations between spherical simple regions and topological relations between regions with holes in the plane have been investigated,few studies have focused on the topological relations between spherical spatial regions with holes.The 16-intersection model(16IM)is proposed to describe the topological relations between spatial regions with holes.A total of 25 negative conditions are proposed to eliminate the impossible topological relations between spherical spatial regions with holes.The results show that(1)3 disjoint relations,3 meet relations,66 overlap relations,7 cover relations,3 contain relations,1 equal relation,7 coveredBy relations,3 inside relations,1 attach relation,52 entwined relations,and 28 embrace relations can be distinguished by the 16IM and that(2)the formalisms of attach,entwined,and embrace relations between the spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on the simplified 16IM are different,whereas the formalisms of other types of relations between spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on a simplified 16IM are the same. 展开更多
关键词 Topological relations spatial region with holes 16-intersection model(16IM) spatial analysis
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Study upon the Spatial Structure of Regional Eco-tourism-Based upon the Perspective of Supply and Demand and Competition Field
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作者 方世敏 赵金金 《Journal of Landscape Research》 2010年第10期51-55,共5页
Along with the coming of the low-carbon era, people have paid more and more attention to the natural environment and eco-tourism will embrace a huge development. From the perspectives of the market relationship of sup... Along with the coming of the low-carbon era, people have paid more and more attention to the natural environment and eco-tourism will embrace a huge development. From the perspectives of the market relationship of supply-demand in economics and of field competition in physics, this paper has discussed upon the present status of the spatial structure of eco-tourism, and analyzed the relationship between supply-demand and field, in order to clarify the direction for the balance between supply and demand in the field and to guide eco-tourism to the way of sustainable development. 展开更多
关键词 regional ECO-TOURISM spatial structure Supply-demand COMPETITIVE FIELD
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Spatial function regionalization and governance of coastal zone: A case study in Ningbo City 被引量:5
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作者 孙伟 陈诚 王磊 《Journal of Geographical Sciences》 SCIE CSCD 2018年第8期1167-1181,共15页
Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources,playing a... Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources,playing an important role in regional sustainable development.Depending on the natural,economic,and societal characteristics of a region,research topics such as using relevant methods to divide the coastline,proper spatial development of the coast,protecting coastal zones,and achieving higher spatial resource distribution efficiency have recently become hot topics in geographic research.Most of the scholars construct the evaluation index system from the perspective of economic and ecological factors and undertake some exploration of the division methods.However,the selection of indicators for a coastal zone needs a different and more scientific approach.There is a need for emphasizing the overall strategy of land-ocean integration in developing spatial resources in a coastal zone.Taking the coastal zone in Ningbo as an example,this paper develops a new evaluation framework and spatial function regionalization method that is used to divide the coastline and coastal zone.Based on the perspective of overall strategy for the land and ocean,we evaluate the suitability of coastline development.We then propose the spatial function regionalization of the coastal zone.Finally,based on the status quo of spatial development in Ningbo,we divide the coastal zone into ecological space,production space and living space,and propose adjustment directions and control requirements for the different types of spatial layouts. 展开更多
关键词 coastal zone COASTLINE spatial function regionalization spatial governance Ningbo City
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Spatial-temporal differences in in-stream flow requirement based on GIS: A case study of Yan'an region, northern Shaanxi 被引量:2
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作者 WANG Lixia REN Zhiyuan 《Journal of Geographical Sciences》 SCIE CSCD 2008年第1期107-114,共8页
Although water has the central function of the bloodstream in the biosphere especially in arid or semi-arid regions such as Yah'an region in northwestern China, yet the very limited attention is paid to the role of t... Although water has the central function of the bloodstream in the biosphere especially in arid or semi-arid regions such as Yah'an region in northwestern China, yet the very limited attention is paid to the role of the water-related processes in ecosystem. In this research, based on continuous nearly 50-year data including runoff volume, sediment discharge as well as sediment accretion from hydrographic stations, and 10-year information of water quality from pollution monitoring stations, the method for measuring in-stream flow requirement has been put forward supported by experiential models and GIS spatial analysis. Additionally, the changes of in-stream flow requirement for environment and economic development have been addressed from spatial-temporal dimensions. The results show that: (1) According to the central streams in Yan'an region, mean annual in-stream flow requirement reaches 1.0619 billion m^3, and the surface water for economic exploitation is 0.2445 billion m3 (2) Mean annual in-stream flow requirement for sediment transfers in flood period occupies over 80% of the integrated volume in a year. (3) From the 1950s to 1970s, in-stream flow requirement for sediment transfers is comparatively higher, while from the 1980s to 1990s, this requirement presents a decreasing tendency. 展开更多
关键词 GIS spatial analysis Yan'an region in-stream flow requirement spatial-temporal differences
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Spatial-temporal dynamics of desert vegetation and its responses to climatic variations over the last three decades:a case study of Hexi region in Northwest China 被引量:14
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作者 YANG Xuemei LIU Shizeng +6 位作者 YANG Taibao XU Xianying KANG Caizhou TANG Jinnian WEI Huaidong Mihretab G GHEBREZGABHER LI Zhiqi 《Journal of Arid Land》 SCIE CSCD 2016年第4期556-568,共13页
Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas. In this study, we used the Global Inv... Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas. In this study, we used the Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data from 1982 to 2006 and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data from 2000 to 2013 to reveal the dynamics of desert vegetation in Hexi region of Northwest China over the past three decades. We also used the annual temperature and precipitation data acquired from the Chinese meteorological stations to analyze the response of desert vegetation to climatic variations. The average value of NDVImax (the maximum NDVI during the growing season) for desert vegetation in Hexi region increased at the rate of 0.65x10-3/a (P〈0.05) from 1982 to 2013, and the significant increases of NDVImax mainly appeared in the typical desert vegetation areas. Vegetation was significantly improved in the lower reaches of Shule and Shiyang river basins, and the weighted mean center of desert vegetation mainly shifted toward the lower reaches of the two basins. Almost 95.32% of the total desert vegetation area showed positive correlation between NDVImax and annual precipitation, indicating that precipitation is the key factor for desert vegetation growth in the entire study area. Moreover, the areas with non-significant positive correlation between NDVImax and annual precipitation mainly located in the lower reaches of Shiyang and Shule river basins, this may be due to human activities. Only 7.64% of the desert vegetation showed significant positive correlation between NDVImax and annual precipitation in the Shule River Basin (an extremely arid area), indicating that precipitation is not the most important factor for vegetation growth in this basin, and further studies are needed to investigate the mechanism for this phenomenon. 展开更多
关键词 desert vegetation NDVI global warming spatial-temporal variations Hexi region
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The regional types of China's floating population: Identification methods and spatial patterns 被引量:9
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作者 LIU Shenghe HU Zhang +1 位作者 DENG Yu WANG Yingjie 《Journal of Geographical Sciences》 SCIE CSCD 2011年第1期35-48,共14页
With the rapid increase of the number and influence of floating population in China,it is urgently needed to understand the regional types of China's floating population and their spatial characteristics. After revie... With the rapid increase of the number and influence of floating population in China,it is urgently needed to understand the regional types of China's floating population and their spatial characteristics. After reviewing the current methods for identifying regional types of floating population,this paper puts forward a new composite-index identification method and its modification version which is consisted of two indexes of the net migration rate and gross migration rate. Then,the traditional single-index and the new composite-index identification methods are empirically tested to explore their spatial patterns and characteristics by using China's 2000 census data at county level. The results show:(1) The composite-index identification method is much better than traditional single-index method because it can measure the migration direction and scale of floating simultaneously,and in particular it can identify the unique regional types of floating population with large scale of immigration and emigration. (2) The modified composite-index identification method,by using the share of a region's certain type of floating population to the total in China as weights,can effectively correct the over-or under-estimated errors due to the rather large or small total population of a region. (3) The spatial patterns of different regional types of China's floating population are closely related to the regional differentiation of their natural environment,population density and socio-economic development level. The three active regional types of floating population are mainly located in the eastern part of China with lower elevation,more than 800 mm precipitation,rather higher population densities and economic development levels. 展开更多
关键词 China floating population regional types spatial pattern composite-index identification method
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Spatial-temporal characteristics of lake area variations in Hoh Xil region from 1970 to 2011 被引量:16
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作者 YAO Xiaojun LIU Shiyin +2 位作者 LI Long SUN Meiping LUO Jing 《Journal of Geographical Sciences》 SCIE CSCD 2014年第4期689-702,共14页
As one of the areas with numerous lakes on the Tibetan Plateau, the Hoh Xil region plays an extremely important role in the fragile plateau eco-environment. Based on topographic maps in the 1970s and Landsat TM/ETM+ ... As one of the areas with numerous lakes on the Tibetan Plateau, the Hoh Xil region plays an extremely important role in the fragile plateau eco-environment. Based on topographic maps in the 1970s and Landsat TM/ETM+ remote sensing images iin the 1990s and the period from 2000 to 2011, the data of 83 lakes with an area above 10 km2 each were obtained by digitization method and artificial visual interpretation technology, and the causes for lake variations were also analyzed. Some conclusions can be drawn as follows. (1) From the 1970s to 2011, the lakes in the Hoh Xil region firstly shrank and then expanded, in particular, the area of lakes generally decreased during the 1970s-1990s. Then the lakes expanded from the 1990s to 2000 and the area was slightly higher than that in the 1970s. The area of lakes dramatically increased after 2000. (2) From 2000 to 2011, the lakes with different area ranks in the Hoh Xil region showed an overall expansion trend. Meanwhile, some regional differences were also discovered. Most of the lakes expanded and were widely distributed in the northern, central and western parts of the region. Some lakes were merged together or overflowed due to their rapid expansion. A small number of lakes with the trend of area decrease or strong fluctuation were scattered in the central and southern parts of the study area. And their variations were related to their own supply conditions or hydraulic connection with the downstream lakes or rivers. (3) The increase in precipitation was the dominant factor resulting in the expansion of lakes in the Hoh Xil region. The secondary factor was the increase in meltwater from glaciers and frozen soil due to climate warming. 展开更多
关键词 lake variation spatial-temporal characteristics Hoh Xil region Tibetan Plateau
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Spatial patterns of ecosystem vulnerability changes during 2001–2011 in the three-river source region of the Qinghai-Tibetan Plateau, China 被引量:19
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作者 GUO Bing ZHOU Yi +8 位作者 ZHU Jinfeng LIU Wenliang WANG Futao WANG Litao YAN Fuli WANG Feng YANG Guang LUO Wei JIANG Lin 《Journal of Arid Land》 SCIE CSCD 2016年第1期23-35,共13页
The three-river source region (TRSR, including Yangtze, Yellow and Lancang rivers), located in the Qinghai-Tibetan Plateau, China, is a typical alpine zone with apparent ecosystem vulnerability and sensitivity. In thi... The three-river source region (TRSR, including Yangtze, Yellow and Lancang rivers), located in the Qinghai-Tibetan Plateau, China, is a typical alpine zone with apparent ecosystem vulnerability and sensitivity. In this paper, we introduced many interdisciplinary factors, such as landscape pattern indices (Shannon diversity index and Shannon evenness index) and extreme climate factors (number of extreme high temperature days, number of extreme low temperature days, and number of extreme precipitation days), to establish a new model for evaluating the spatial patterns of ecosystem vulnerability changes in the TRSR. The change intensity (CI) of ecosystem vulnerability was also analyzed. The results showed that the established evaluation model was effective and the ecosystem vulnerability in the whole study area was intensive. During the study period of 2001–2011, there was a slight degradation in the eco-environmental quality. The Yellow River source region had the best eco-environmental quality, while the Yangtze River source region had the worst one. In addition, the zones dominated by deserts were the most severely deteriorated areas and the eco-environmental quality of the zones occupied by evergreen coniferous forests showed a better change. Furthermore, the larger the change rates of the climate factors (accumulative temperature of ≥10°C and annual average precipitation) are, the more intensive the CI of ecosystem vulnerability is. This study would provide a scientific basis for the eco-environmental protection and restoration in the TRSR. 展开更多
关键词 eco-environmental vulnerability climate factors spatial patterns three-river source region
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The measurement of the spatial effects of Chinese regional carbon emissions caused by exports 被引量:2
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作者 TANG Zhipeng 《Journal of Geographical Sciences》 SCIE CSCD 2015年第11期1328-1342,共15页
Based on the multi-regional input-output analysis, this paper improves the four traditional input-output formulas about exports resulting in multi-regional carbon emissions spatial effects which include direct effect,... Based on the multi-regional input-output analysis, this paper improves the four traditional input-output formulas about exports resulting in multi-regional carbon emissions spatial effects which include direct effect, indirect effect, spillover effect and feedback effect. And the latter two formulas are to measure the bidirectional influences of carbon emissions induced by regional exports between two regions. The results suggest that the direct effects of Chinese eight regions induced by national exports decreased from 1997 to 2010, and the indirect effects induced by national exports also decreased except the northern coastal region and the northwestern region in China. During this period, most of Chinese coastal regions had strong spillover effects induced by their own exports. The northern coastal region and the eastern coastal region had stronger feedback effects, while the southern coastal region had weaker feedback effects and Beijing-Tianjin region had the weakest feedback effect induced by their exports. All of the inland regions had strong feedback effects, especially for Northwest and Central China, induced by their exports. More attention should be paid to the inter-regional joint efforts in order to effectively achieve Chinese national carbon-reduction target. 展开更多
关键词 EXPORT region carbon emissions spatial effects INPUT-OUTPUT
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Aging effects of regional activation in a spatial task A functional magnetic resonance imaging study 被引量:1
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作者 Jong-Rak Park Dae-Woon Lim +6 位作者 Mi-Hyun Choi Su-Jeong Lee Jin-Seung Choi Hyung-Sik Kim Jeong-Han Yi Gye-Rae Tack Soon-Cheol Chung 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第9期663-667,共5页
BACKGROUND: An increasing number of studies have shown the effects of aging in basic cognitive processing and higher cognitive functions using functional magnetic resonance imaging (fMRI). However, little is known ... BACKGROUND: An increasing number of studies have shown the effects of aging in basic cognitive processing and higher cognitive functions using functional magnetic resonance imaging (fMRI). However, little is known about the aging effects in diverse cognitive abilities, such as spatial learning and reasoning. OBJECTIVE: To investigate the effect of aging on spatial cognitive performance and regional brain activation based on fMRI. DESIGN, TIME, AND SETTING: A block design for fMRI observation. This study was performed at the fMRI Laboratory, Brain Science Research Center, Korea Advanced Institute of Science and Technology from March 2006 to May 2009. PARTICIPANTS: Eight right-handed, male, college students in their 20s (mean age 21.5 years) and six right-handed, male, adults in their 40s (mean age 45.7 years), who graduated from college, participated in the study. All subjects were healthy and had no prior history of psychiatric or neurological disorders. METHODS: A spatial task was presented while brain images were acquired using a 3T fMRI system (ISOL Technology, Korea). The spatial tasks involved selecting a shape that corresponded to a given figure using four examples, as well as selecting a development figure of a diagram. MAIN OUTCOME MEASURES: The accuracy rate (number of correct answers/total number of items x 100%) of spatial tasks was calculated. Using the subtraction procedure, the activated areas in the brain during spatial tasks were color-coded by T-score. The double subtraction method was used to analyze the effect of aging between the two age groups (20s versus 40s). RESULTS: The cerebellum, occipital lobe, parietal lobe, and frontal lobe were similarly activated in the two age groups. Increased brain activations, however, were observed in bilateral parietal and superior frontal lobes of the younger group. More activation was observed in bilateral middle frontal and right inferior frontal lobes in the older group. Compared with the older group, the younger men exhibited greater spatial performance (P = 0.012). CONCLUSION: Reduced cognitive function correlated with decreased activation areas in the parietal lobe and altered activation in the frontal lobe. 展开更多
关键词 functional magnetic resonance imaging AGING regional activation spatial task
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Spatial Agglomeration of Exhibition Enterprises on a Regional Scale in China 被引量:1
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作者 FANG Zhongquan ZHANG Ying +1 位作者 WANG Zhangjun ZHANG Lifeng 《Chinese Geographical Science》 SCIE CSCD 2017年第3期497-506,共10页
During the past two decades, the exhibition industry in China has been developing rapidly and has become an important part of the modern service industry, particularly the agglomeration characteristics of exhibition e... During the past two decades, the exhibition industry in China has been developing rapidly and has become an important part of the modern service industry, particularly the agglomeration characteristics of exhibition enterprises highlighted on the regional scale. Although the development of theoretical research on the western exhibition industry has taken place over time, the spatial perspective has not been at the centre of attention so far. This paper aims to fill this gap and report on the agglomeration characteristics of exhibition enterprises and their influential factors. Based on data about exhibition enterprises in the Pearl River Delta(PRD) during 1991–2013, using the Ripley K function analysis and kernel density estimation, this research identifies that: 1) the exhibition enterprise on the regional scale is significantly characterized by spatial agglomeration, and the agglomeration density and scale are continuously increasing; 2) the spatial pattern of agglomeration has developed from a single-center to multi-center form. Meanwhile, this paper profiles the factors influencing the spatial agglomeration of exhibition enterprises by selecting the panel data of nine cities in the PRD in 1999, 2002, 2006 and 2013. The results show that market capacity, urban informatization level and exhibition venues significantly influence the location choice of exhibition enterprises. Among them, the market capacity is a variable that exerts a far greater impact than other factors do. 展开更多
关键词 exhibition enterprises spatial agglomeration Ripley K function analysis regional scale Pearl River Delta
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Changes and spatial patterns of eco-environment in the farming-pastoral region of northern China 被引量:2
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作者 JIANG Weiguo LI Jing +2 位作者 LI Jiahong CHEN Yunhao WU Yongfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期329-336,共8页
This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then di... This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then discusses in detail the methods about evaluating eco-environment background condition and analyzing eco-environment change. The eco-environment background conditions of 1989 and 1999 are synthetically appraised. Finally, the paper analyzes the spatial distribution, quantitative change, the trend of change, the areas of change and the dynamic spatial pattern of eco-environment. The results are as follows: (1) The eco-environment background condition becomes worse from southeast to northwest in the fanning-pastoral region of northern China. (2) The eco-environment background condition deteriorates from 1989 to 1999. (3) In the adjacent areas of Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia, Horqin Sandy Land and its peripheries, and eastern Qinghai orovince, eco-environmental deterioration is very serious. 展开更多
关键词 fanning-pastoral region ECO-ENVIRONMENT spatial pattern northern China
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Quantitative method for calculating spatial release region for laser-guided bomb
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作者 YANG Ping XIAO Bing +1 位作者 CHEN Xin HAO Yuntao 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期1053-1062,共10页
The laser-guided bomb(LGB)is an air-to-ground pre-cision-guided weapon that offers high hit rates,great power,and ease of use.LGBs are guided by semi-active laser ground-seek-ing technology,which means that atmospheri... The laser-guided bomb(LGB)is an air-to-ground pre-cision-guided weapon that offers high hit rates,great power,and ease of use.LGBs are guided by semi-active laser ground-seek-ing technology,which means that atmospheric conditions can affect their accuracy.The spatial release region(SRR)of LGBs is difficult to calculate precisely,especially when there is a poor field of view.This can result in a lower real hit probability.To increase the hit probability of LGBs in tough atmospheric situa-tions,a novel method for calculating the SRR has been pro-posed.This method is based on the transmittance model of the 1.06μm laser in atmospheric species and the laser diffuse reflection model of the target surface to determine the capture target time of the laser seeker.Then,it calculates the boundary ballistic space starting position by ballistic model and gets the spatial scope of the spatial release region.This method can determine the release region of LGBs based on flight test data such as instantaneous velocity,altitude,off-axis angle,and atmospheric visibility.By more effectively employing aircraft release conditions,atmospheric visibility and other factors,the SRR calculation method can improve LGB hit probabi-lity by 9.2%. 展开更多
关键词 laser-guided bombs(LGBs) hit probability atmo-spheric transmittance spatial release region(SRR)boundary ballistic
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Spatial Function Regionalization Based on an Ecological-economic Analysis in Wuxi City, China
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作者 SUN Wei CHEN Wen JIN Zhifeng 《Chinese Geographical Science》 SCIE CSCD 2019年第2期352-362,共11页
As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundw... As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundwork for the regulation of land use and protection. This paper probes the system of evaluation indices and applies the methods of spatial analysis and classification clustering to the calculation of the ecologically significant value and economically significant value in each evaluation unit. After use of a classification matrix integrated by the two significant values, city space can be divided into four functional types, namely, feasible development area, moderate development area, moderate conservation area and prohibited exploiting area, and these are the basis for spatial development and control. 展开更多
关键词 spatial FUNCTION regionALIZATION spatial analysis ecologically SIGNIFICANT VALUE economically SIGNIFICANT VALUE urbanized region
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A study on the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region, China 被引量:6
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作者 GUO Liying YANG Ren WANG Daolong 《Journal of Geographical Sciences》 SCIE CSCD 2012年第4期761-768,共8页
The Bohai Rim region is one the most important bases for commodity grain production in China. With the rapid pace of agricultural industrialization, nitrogenous fertilizer has been used at an ever increasing rate, whi... The Bohai Rim region is one the most important bases for commodity grain production in China. With the rapid pace of agricultural industrialization, nitrogenous fertilizer has been used at an ever increasing rate, which resulted in the trace of accumulative nitrogen in the soil and caused serious environmental problems. In this study we made use of the farmland nitrogen balance model to assess the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region in 2008 with the assistance of GIS. Our results indicated that: 1) Farmland in this region has a nitrogen surplus totaling 5.0822 million tons, or an average of 288.54 kg/ha. 2) In the Bohai Rim region, farmland nitrogen input and farmland nitrogen budget both show a spatial differentiation. Major grain-producing areas have a higher nitrogen input than that of the grazing-farming areas. The main sources of nitrogen input include chemical fertilizer, organic fertilizer, deposition from atmospheric drying and wetting, and biological fixation, which account for 79.47%, 9.53%, 4.62%, and 3.58% of the total input, respectively. Therefore, chemical fertilizer is the predominant source of nitrogen input to farmland. 3) A total of 3.3398 million tons of nitrogen were output from the farmland via harvested crops and it accounts for 52.36% of the total nitrogen output from farmland in this region. On average, the amount of nitrogen output from unit farmland is equal to 176.65kg/ha. This study has shed light on farmland nitrogen budget and its spatial variation in the study area, may provide scientific evidences for rationalizing the use of chemical fertilizer and managing agricultural operation on the regional scale and is also valuable for improving the economic and ecological efficiency of fertilizer use at the regional scale. 展开更多
关键词 farmland nitrogen nutrient nitrogen budget spatial difference agricultural production the BohaiRim region
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Temporal-spatial change and driving mechanism for regional difference of domestic tourism in China 被引量:1
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作者 Degen Wang Tian Chen 《Chinese Journal of Population,Resources and Environment》 2013年第1期69-78,共10页
By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism ... By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism in China from 1995 to 2009.According to the results,we drew the following conclusions:(1)The regional difference of domestic tourism in China tends to be narrowing generally,and is less than that of inbound tourism,playing an important role in narrowing the overall gap of regional tourism in China.(2)The regional internal difference features:inter-provincial difference in the eastern region and difference among the eastern,central and western regions are comparatively obvious and demonstrate a significantly shrinking tendency,the change tendency is consistent with the change tendency of overall difference and exercises a decisive role in overall difference,whereas the inter-provincial difference in the central and western regions is small and relatively stable,having less influence on the overall difference.(3)The temporal-spatial change in regional difference is featured by:low-level provinces occupy a majority and are concentrated in the central and western regions,showing a tendency of narrowing difference;high-level provinces are concentrated in the eastern region,showing a tendency of spreading to the central and western regions;spatial pattern of regional difference demonstrates 4 types,i.e."proliferation type","polarization type","quiescence type"and"collapse type."(4)The driving force for regional difference of domestic tourism in China comes down to 3 aspects:regional socio-economic attribute,regional transport accessibility level and regional development policy. 展开更多
关键词 DOMESTIC TOURISM regionAL DIFFERENCE temporal-spatial CHANGE driving mechanism China
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An overview of the spatial patterns of land surface processes over arid and semiarid regions 被引量:6
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作者 Jian Zeng Jie Shen Qiang Zhang 《Research in Cold and Arid Regions》 2010年第4期288-297,共10页
With data from the project Collaborative Observation of Semi-arid/Arid Regions in North China, collected during July and September 2008, the spatial patterns of land surface processes over arid and semiarid regions ha... With data from the project Collaborative Observation of Semi-arid/Arid Regions in North China, collected during July and September 2008, the spatial patterns of land surface processes over arid and semiarid regions have been investigated based on the ordinary Kriging interpolation approach. Generally, for the radiation processes, downward and upward short-wave radiation have a uniformly increasing trend with latitude, but the spatial patterns of long-wave radiation present notable regional differences: both upward and downward long-wave radiation increase with latitude in the west of North China, while in the east they vary inversely with latitude, suggesting surface temperature and clouds respectively have feedbacks to the long-wave radiation in the west and east of North China. The surface net radiation basically has a negative latitudinal trend. Long-wave radiation budget plays an important role in the spatial pattern of surface net radiation, particularly in the east of North China, although short-wave radiation budget largely determines the magnitude of surface net radiation. For the energy processes, latent and sensible heat flux varies conversely with latitude: more available land surface energy is consumed by evaporating soil water at lower latitudes while more is used for heating the atmosphere at higher latitudes. A soil heat flux maximum and minimum are found in Loess Plateau and Qinghai Plateau respectively, and a maximum is seen in the northeast China. 展开更多
关键词 land surface radiation processes land surface energy processes spatial pattern arid and semiarid regions
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THE ECONOMIC IMPACT OF SPATIAL ORGANZATIONAL STRUCTURES ON THE PROVINCIAL BORDER-REGIONS OF CHINA
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作者 郭荣星 《Chinese Geographical Science》 SCIE CSCD 1994年第3期204-209,共6页
Based on the spatial organizational structures of the provincial border-regions (a border-region is one which borders two or more independent administrative regions), we build a spatial economic model for N-provincia... Based on the spatial organizational structures of the provincial border-regions (a border-region is one which borders two or more independent administrative regions), we build a spatial economic model for N-provincial border-regions (a N-p border-region is one which is under the jurisdiction of N provincial governments) and find that, for a given region with same geographical condition and resources endowment, the largest output of a N-p border-regional system will not exceed that ofa (N-1)-p border-regional system, i.e., F. Using the model in this paper, we present a quantitative method to calculate the economic impacts of 'provincial borders' and apply it to the border-region of Shanxi, Hebei, Shangdong, and Henan provinces. The result shows that the economic potential in the border-region hasnot been efficiently exploited and that the annual gross agricultural products have decreased by 10.4% due to the 4-p borders. 展开更多
关键词 PROVINCE border-region spatial ORGANIZATION chinese ECONOMY
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A spatial geostatistical analysis of impact of land use development on groundwater resources in the Sangong Oasis Region using remote sensing imagery and data 被引量:6
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作者 Chen, Xi Yan, JinFeng +3 位作者 Chen, Zhi Luo, GePing Song, Qing Xu, WenQiang 《Journal of Arid Land》 SCIE 2009年第1期1-8,共8页
In this study, the relationship between land use and cover change (LUCC) and variation of groundwater level and quality in the Sangong Oasis Region was investigated using a spatial geostatistical approach. Specificall... In this study, the relationship between land use and cover change (LUCC) and variation of groundwater level and quality in the Sangong Oasis Region was investigated using a spatial geostatistical approach. Specifically, interactions among groundwater, surface water, and LUCC were analyzed through the utilization of geographical information system (GIS), remote sensing (RS) Imagery processing, and geostatistics. Study outputs indicated that recharging into the groundwater did not change significantly during the period from 1978 to 1998. However, both LUCC and groundwater level changed substantially in the Sangong Oasis Region, and their variations were closely correlated to each other spatially and temporally over the past two decades. It confirmed that urbanization process and increased industrial activities were the direct reasons of groundwater table descending and the deterioration of water quality. The results of this research provided a scientific basis for understanding sustainability-related problems and solution options in the oasis areas of western China. 展开更多
关键词 spatial analysis remote sensing LUCC GROUNDWATER Sangong Oasis region
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Analysis of the Spatial Distribution Characteristics of Abnormal Bone Density in Male Long-Distance Runners from Different Regions in China
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作者 Longxing Fan Wenjie Zhang +2 位作者 Huanhuan Cui Yanqing Liu Ziquan Liu 《Open Journal of Epidemiology》 2021年第1期80-91,共12页
Objective: To investigate the occurrence pattern of abnormal bone density in male long-distance runners from several different regions of China, and provide a basis for elucidating the influences of geo-environmental ... Objective: To investigate the occurrence pattern of abnormal bone density in male long-distance runners from several different regions of China, and provide a basis for elucidating the influences of geo-environmental differences on bone density. Methods: We employed a set of well-designed exclusion-inclusion criteria to recruit study subjects, in which compounding factors were managed and regional environmental traits were fully incorporated. WHO (World Health Organization) criteria for the diagnosis of osteoporosis were then used to examine the subjects to determine occurrence of abnormal bone density. The resulting data were analyzed using methods of spatial statistics, which included several approaches, such as spatial autocorrelation, hot spot analysis, and Geodetector Software analysis, to depict and analyze the spatial distribution of abnormal bone density in male athletes from different regions in China, thereby investigating the influences of geo-environmental factors (e.g., temperature, humidity, and altitude) on bone density. Results: A total of 685 subjects were effectively examined in this study, including 486 with normal bone density, 185 with osteopenia, and 14 with osteoporosis. Spatial distribution analysis revealed that the distribution of subjects with abnormal bone density overall exhibited a pattern indicating that the level of abnormal bone density in the eastern regions was higher than that in the western regions and that the levels of abnormal bone density in the southern and northern regions were higher than that in the middle regions. Spatial autocorrelation analysis revealed a Moran’s I = 0.136, Z-score = 1.114, and P value = 0.265 and indicated that the athletes with abnormal bone density were randomly distributed in each region. Hot spot analysis revealed that Tibet and Qinghai displayed distributions of cold spots. Geodetector Software analysis yielded a Q value for annual average temperature of 1.000 and a corresponding P value of 0.000, and the results revealed that temperature significantly affected bone density and that altitude, relative humidity, sunlight hours, and temperature variations displayed synergistic effects on bone density and could diminish the influences of temperature on bone density. Conclusion: Our data revealed that different regions displayed different distribution patterns of abnormal bone density such that the level in the eastern regions was higher than that in the western ones and that the levels in the southern and northern regions were higher than that in the middle regions;specifically, the provinces of Yunnan, Heilongjiang, Hainan, and Inner Mongolia had high rates of abnormal bone density, whereas Tibet and Qinghai had relatively good conditions of bone density. Our data suggested that suitable temperature changes and appropriate levels of temperature variations can decrease the occurrence rates of osteopenia and osteoporosis. 展开更多
关键词 spatial Epidemiology regionS ATHLETES Bone Density
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