Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-tempora...Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-temporal Landsat TM and Landsat ETM+ data were employed to identify patterns of LUCC as well as to quantify urban expansion and the associated decrease of vegetation cover. The thermal infrared bands of the data were used to retrieve LST. The results revealed a strong and uneven urban growth,which caused LST to raise 4.56℃in the newly urbanized part of the study area. Overall, remote sensing and GIS technologies were effective approaches for monitoring and analyzing urban growth patterns and evaluating their impacts on LST.展开更多
The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will b...The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will be 23 550 thousand by year of 2000. While the population in being in EAZD was 22.62 million in 1999.This accords with the prefigured result in the rough from the point of view of development. According to the data of plow land resources from the 2000 Statistical Yearbook of EAZD and the study on the population-foodstuff-plow land relationship, this paper calculates the productive potential of plow land and the population carrying capacity of land by year of 2010, and puts forward the countermeasures for improving the population carrying capacity of land in this region.展开更多
In this paper, Shunde City is selected as a typical region standing for the Zhujiang Delta because of its excellent location and dike-pond system.There are three main characters of agricultural land use in this region...In this paper, Shunde City is selected as a typical region standing for the Zhujiang Delta because of its excellent location and dike-pond system.There are three main characters of agricultural land use in this region. First, the most typical land use form is dike-pond system. It is a special form of artificial ecosystem of land-water interaction. Second, sandy field is also an important land type in this region. Third, land use is greatly influenced by export-oriented economy. Recently, with economic reforming and the opening up of the Zhujiang Delta, the structure of agricultural land use has been changed greatly. The area of mulberry dike has decreased and a variety of planting crops has increased.Various structure of dike-pond farming has emerged in the Zhujiang Delta such as 'fruit dike-fish pond', 'flower dike-fish pond', 'grass dike-fish pond', 'vegetable dike-fish pond'. The area of water has slightly increased and its development tends to modernization due to the use of modern equipment and advanced breeding ways. The area for 'three high'(high yield, high quality and high efficiency) agriculture has increased greatly.展开更多
As the Central Place Theory indicates, the centricity of a central city can influence the extension of its ser- vice. Since the service industry in the theory is mostly consumer services, it is worth studying the rela...As the Central Place Theory indicates, the centricity of a central city can influence the extension of its ser- vice. Since the service industry in the theory is mostly consumer services, it is worth studying the relationship between the producer services and the centricity of the city in the service society with producer services becoming a more im- portant part of the service industry. The paper takes the case of the Zhujiang (Pearl) River Delta (PRD), a developed region in China, to study the relationship between the developing level of producer services and the urban hierarchy. Based on the analysis about the spatial difference of the producer services in the nine cities of the PRD, and the divi- sion of the nine cities according to some economic indices, it is shown that there is a correlation between the develop- ing level of producer services and the urban hierarchy. Furthermore, two deductions about the future status of the pro- ducer services in the city and the location of the producer services in a large region can be made from this correlation between the developing level of producer services and the urban hierarchy.展开更多
Projections of potential submerged area due to sea level rise are helpful for improving understanding of the influence of ongoing global warming on coastal areas. The Ensemble Empirical Mode Decomposition method is us...Projections of potential submerged area due to sea level rise are helpful for improving understanding of the influence of ongoing global warming on coastal areas. The Ensemble Empirical Mode Decomposition method is used to adaptively decompose the sea level time series in order to extract the secular trend component. Then the linear relationship between the global mean sea level (GMSL) change and the Zhujiang (Pearl) River Delta (PRD) sea level change is calculated: an increase of 1.0 m in the GMSL corresponds to a 1.3 m (uncertainty interval from 1.25 to 1.46 m) increase in the PRD. Based on this relationship and the GMSL rise projected by the Coupled Model Intercomparison Project Phase 5 under three greenhouse gas emission scenarios (representative concentration pathways, or RCPs, from low to high emission scenarios RCP2.6, RCP4.5, and RCP8.5), the PRD sea level is calculated and projected for the period 2006-2100. By around the year 2050, the PRD sea level will rise 0.29 (0.21 to 0.40) m under RCP2.6, 0.31 (0.22 to 0.42) m under RCP4.5, and 0.34 (0.25 to 0.46) m under RCP8.5, respectively. By 2100, it will rise 0.59 (0.36 to 0.88) m, 0.71 (0.47 to 1.02) m, and 1.0 (0.68 to 1.41) m, respectively. In addition, considering the extreme value of relative sea level due to land subsidence (i.e., 0.20 m) and that obtained from intermonthly variability (i.e., 0.33 m), the PRD sea level will rise 1.94 m by the year 2100 under the RCP8.5 scenario with the upper uncertainty level (i.e., 1.41 m). Accordingly, the potential submerged area is 8.57x103 km2 for the PRD, about 1.3 times its present area.展开更多
The Zhujiang (Pearl) River Delta is one of the most developed Extended Metropolitan Regions (EMR) in China.With the rapid urbanization,the agglomeration of population and industries has emerged,which has led to dramat...The Zhujiang (Pearl) River Delta is one of the most developed Extended Metropolitan Regions (EMR) in China.With the rapid urbanization,the agglomeration of population and industries has emerged,which has led to dramatic changes of spatial structure and land use in this region.With data of high resolution TM remote sensing images and Google Earth maps,this paper identified and analyzed the spatial pattern of the Zhujiang River Delta EMR using Envy and ArcGIS tools.It was found that 1) the industrial land uses were expanding substantially,particularly on the bank sides of the Zhujiang River estuary;2) large-scale housing developments were concentrated in the fringe of metropolitan areas such as those of Guangzhou and Shenzhen;3) a regional transportation network with the spatial pattern of ″1 circle +2 pieces + 3 axes″ had significantly affected the location choice of manufacture enterprises.At the same time,both highly specialized land use and severely mixed land use patterns were identified.As a consequence of the latter,land use efficiency of the whole EMR areas was reduced.Moreover,ecologic and environmental problems were severe.Based on the above analysis,suggestions were given from the viewpoint of spatial safety,land use efficiency,and the reorganization of spatial structure in the Zhujiang River Delta EMR.展开更多
In traditional urban geography, city contact research is a classic study element in city research. In general, researchers use the traditional gravity model to characterize the contacts that exist between two cities. ...In traditional urban geography, city contact research is a classic study element in city research. In general, researchers use the traditional gravity model to characterize the contacts that exist between two cities. The traditional gravity model assumes ideal conditions, but these preconditions and their results often do not exist in realistic conditions. Thus, we used a modified gravity model to characterize the city contacts within a specific region. This model considers factors such as intercity complementarities, government intervention, and the diversity of the transportation infrastructure which is characterized as the transportation distance instead of the traditional Euclidean distance. We applied this model to an empirical study of city contact in the Zhujiang(Pearl) River Delta(PRD) of China. The regression results indicated that the modified gravity model could measure city contact more accurately and comprehensively than the traditional gravity model, i.e., it yielded a higher adjusted R2 value(0.379) than the traditional gravity model result(0.259). Our study also suggests that, in addition to urban-regional and metropolitan development, the complementarities of the basic functions of cities at the administrative and market levels, as well as the corporeal and immaterial levels, play very significant roles in the characterization of city contact. Given the complexity of city contact, it will be necessary to consider more relevant influential factors in the modified gravity model to characterize the features of city contact in the future.展开更多
By analysing comprehensively the factors such as theoretical sealevel, abnormal fluctuation of sea level, rising amplitude of floodtide water level and land deformation, a rising amplitude of 22-33 cm of relative sea ...By analysing comprehensively the factors such as theoretical sealevel, abnormal fluctuation of sea level, rising amplitude of floodtide water level and land deformation, a rising amplitude of 22-33 cm of relative sea level by the year of 2030 is forecasted in the Zhujiang Delta. From the forecasted amplitude of 30 cm, using hydraulic and hydrometric models the scope influenced by sea level rise is delimited and the reappearing periods of floodtide water level, protecting ability of embankments, design parameters of water conservancy project, drain waterlogging, saline intrusion, resource of mud beach and comprehensive prevention measures are discussed.展开更多
since 1978, rural urbanization has been accelerated in the Zhujiang (Pearl) River Delta because of the rapid development of commodity agriculture, industrialization and tertiary industry. Its natural urban population ...since 1978, rural urbanization has been accelerated in the Zhujiang (Pearl) River Delta because of the rapid development of commodity agriculture, industrialization and tertiary industry. Its natural urban population increase had been mostly mechanical before now, and the towns have been transformed from traditional centers into those serving various functions, particularly industrial ones.In the Zhujiang River Delta, population density and the level of economic changes are high in central areas, and low in outlying area, but on the other hand, urban population has increased slowly in central area and fast in outlying area. In the central areas more industrial towns emerge. So the gap has been greatly reduced. The reform of the construction of the region’s economy, the improvement of transportation, the adjustment of the standard of town setting have promoted the distribution of the towns in the Zhujiang River Delta from being centralized to balanced.展开更多
A linear regression analysis of 28 selected tide-gauge stations of the Zhujiang Estuary shows that there has been a tendency of local sea level rise at a rate of 2.028 mm per year. The origin of the variation is signi...A linear regression analysis of 28 selected tide-gauge stations of the Zhujiang Estuary shows that there has been a tendency of local sea level rise at a rate of 2.028 mm per year. The origin of the variation is significantly attributed to the local tectonic movement of discrepant fault-block. Based on this, four types of relative local sea level changes are classified. According to calculation, half of the fertile land, or 800 km2 of the delta plain will have been submerged by sea water by about 2040. This will yield a significant influence on the economic construction and human activities.展开更多
The Zhujiang (Pearl) River Delta is the rapid economic development region in China since the opening and reform door policy was carried out in 1978. Being the rapid development of industry and city, the impact on the...The Zhujiang (Pearl) River Delta is the rapid economic development region in China since the opening and reform door policy was carried out in 1978. Being the rapid development of industry and city, the impact on the aquatic environmental quality was sig展开更多
The spatial distribution of meteorological elements is important for understanding the regional meteorology and climate changes. However,previous studies rarely focused on the daily changes of the spatial patterns of ...The spatial distribution of meteorological elements is important for understanding the regional meteorology and climate changes. However,previous studies rarely focused on the daily changes of the spatial patterns of meteorological elements due to the limitation of remote sensing(RS) techniques and traditional meteorological methods. In this paper,the regional meteorological elements were simulated by the fifth-generation non-hydrostatic Mesoscale Model(MM5) ,and the spatial patterns of meteorological elements and their diurnal variations were analyzed in landscape level over the Pearl(Zhujiang) River Delta(PRD) ,China. The results showed that there were several centers of urban heat islands,cold islands,dry islands,wet islands,high wind over the PRD at noon. The diurnal changes of Moran I of meteorological elements were obvious and they reached the extremum at noon and 2-3 hours after the sunrise. The landscape indices of meteorological elements,such as area-weighted mean Fractal Dimension Index(FRAC_AM) ,Landscape Shape Index(LSI) ,Shannon's Diversity Index(SHDI) and Contagion Index(CONTAG) ,were more variable at about the sunrise,noon and sunset. The occurrence of wave crests and vales of landscape indices was affected by the surface net radiation,turbulence and local circumfluence. The spatial patterns of meteorological elements correlated well with the land surface,thermal exchanges and local circumfluence. A new approach combining GIS,RS and numerical simulations technologies and the landscape ecology method was presented to analyze spatial patterns of meteorological elements,which may be useful for studying global and regional climate changes.展开更多
基金Project supported by the Science and Technology Project Foundation of Guangzhou (No. 2005Z3-D0551)the Science and Technology Project Foundation of Guangzhou Education Bureau (No. 62026)
文摘Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-temporal Landsat TM and Landsat ETM+ data were employed to identify patterns of LUCC as well as to quantify urban expansion and the associated decrease of vegetation cover. The thermal infrared bands of the data were used to retrieve LST. The results revealed a strong and uneven urban growth,which caused LST to raise 4.56℃in the newly urbanized part of the study area. Overall, remote sensing and GIS technologies were effective approaches for monitoring and analyzing urban growth patterns and evaluating their impacts on LST.
文摘The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will be 23 550 thousand by year of 2000. While the population in being in EAZD was 22.62 million in 1999.This accords with the prefigured result in the rough from the point of view of development. According to the data of plow land resources from the 2000 Statistical Yearbook of EAZD and the study on the population-foodstuff-plow land relationship, this paper calculates the productive potential of plow land and the population carrying capacity of land by year of 2010, and puts forward the countermeasures for improving the population carrying capacity of land in this region.
文摘In this paper, Shunde City is selected as a typical region standing for the Zhujiang Delta because of its excellent location and dike-pond system.There are three main characters of agricultural land use in this region. First, the most typical land use form is dike-pond system. It is a special form of artificial ecosystem of land-water interaction. Second, sandy field is also an important land type in this region. Third, land use is greatly influenced by export-oriented economy. Recently, with economic reforming and the opening up of the Zhujiang Delta, the structure of agricultural land use has been changed greatly. The area of mulberry dike has decreased and a variety of planting crops has increased.Various structure of dike-pond farming has emerged in the Zhujiang Delta such as 'fruit dike-fish pond', 'flower dike-fish pond', 'grass dike-fish pond', 'vegetable dike-fish pond'. The area of water has slightly increased and its development tends to modernization due to the use of modern equipment and advanced breeding ways. The area for 'three high'(high yield, high quality and high efficiency) agriculture has increased greatly.
基金Foundation item: Under the auspices of National Natural Science Foundation of China (No. 40125003, No. 40601029)Natural Science Foundation of Guangdong Province (No. 06300790)
文摘As the Central Place Theory indicates, the centricity of a central city can influence the extension of its ser- vice. Since the service industry in the theory is mostly consumer services, it is worth studying the relationship between the producer services and the centricity of the city in the service society with producer services becoming a more im- portant part of the service industry. The paper takes the case of the Zhujiang (Pearl) River Delta (PRD), a developed region in China, to study the relationship between the developing level of producer services and the urban hierarchy. Based on the analysis about the spatial difference of the producer services in the nine cities of the PRD, and the divi- sion of the nine cities according to some economic indices, it is shown that there is a correlation between the develop- ing level of producer services and the urban hierarchy. Furthermore, two deductions about the future status of the pro- ducer services in the city and the location of the producer services in a large region can be made from this correlation between the developing level of producer services and the urban hierarchy.
基金The Strategic Priority Research Program of the Chinese Academy of Sciences No.XDA11010404the National Natural Science Foundation of China under contract Nos 41375096,41175079 and 41405082the Macao Meteorological and Geophysical Bureau Project under contract No.9231048
文摘Projections of potential submerged area due to sea level rise are helpful for improving understanding of the influence of ongoing global warming on coastal areas. The Ensemble Empirical Mode Decomposition method is used to adaptively decompose the sea level time series in order to extract the secular trend component. Then the linear relationship between the global mean sea level (GMSL) change and the Zhujiang (Pearl) River Delta (PRD) sea level change is calculated: an increase of 1.0 m in the GMSL corresponds to a 1.3 m (uncertainty interval from 1.25 to 1.46 m) increase in the PRD. Based on this relationship and the GMSL rise projected by the Coupled Model Intercomparison Project Phase 5 under three greenhouse gas emission scenarios (representative concentration pathways, or RCPs, from low to high emission scenarios RCP2.6, RCP4.5, and RCP8.5), the PRD sea level is calculated and projected for the period 2006-2100. By around the year 2050, the PRD sea level will rise 0.29 (0.21 to 0.40) m under RCP2.6, 0.31 (0.22 to 0.42) m under RCP4.5, and 0.34 (0.25 to 0.46) m under RCP8.5, respectively. By 2100, it will rise 0.59 (0.36 to 0.88) m, 0.71 (0.47 to 1.02) m, and 1.0 (0.68 to 1.41) m, respectively. In addition, considering the extreme value of relative sea level due to land subsidence (i.e., 0.20 m) and that obtained from intermonthly variability (i.e., 0.33 m), the PRD sea level will rise 1.94 m by the year 2100 under the RCP8.5 scenario with the upper uncertainty level (i.e., 1.41 m). Accordingly, the potential submerged area is 8.57x103 km2 for the PRD, about 1.3 times its present area.
基金Under the auspices of National Natural Science Foundation of China (No.40901088,40671063)Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-YW-321)China Postdoctoral Science Foundation (No.20080440513,200902134)
文摘The Zhujiang (Pearl) River Delta is one of the most developed Extended Metropolitan Regions (EMR) in China.With the rapid urbanization,the agglomeration of population and industries has emerged,which has led to dramatic changes of spatial structure and land use in this region.With data of high resolution TM remote sensing images and Google Earth maps,this paper identified and analyzed the spatial pattern of the Zhujiang River Delta EMR using Envy and ArcGIS tools.It was found that 1) the industrial land uses were expanding substantially,particularly on the bank sides of the Zhujiang River estuary;2) large-scale housing developments were concentrated in the fringe of metropolitan areas such as those of Guangzhou and Shenzhen;3) a regional transportation network with the spatial pattern of ″1 circle +2 pieces + 3 axes″ had significantly affected the location choice of manufacture enterprises.At the same time,both highly specialized land use and severely mixed land use patterns were identified.As a consequence of the latter,land use efficiency of the whole EMR areas was reduced.Moreover,ecologic and environmental problems were severe.Based on the above analysis,suggestions were given from the viewpoint of spatial safety,land use efficiency,and the reorganization of spatial structure in the Zhujiang River Delta EMR.
基金Under the auspices of National Natural Science Foundation of China(No.41271177)Guangdong Natural Science Foundation(No.S2012010008902)
文摘In traditional urban geography, city contact research is a classic study element in city research. In general, researchers use the traditional gravity model to characterize the contacts that exist between two cities. The traditional gravity model assumes ideal conditions, but these preconditions and their results often do not exist in realistic conditions. Thus, we used a modified gravity model to characterize the city contacts within a specific region. This model considers factors such as intercity complementarities, government intervention, and the diversity of the transportation infrastructure which is characterized as the transportation distance instead of the traditional Euclidean distance. We applied this model to an empirical study of city contact in the Zhujiang(Pearl) River Delta(PRD) of China. The regression results indicated that the modified gravity model could measure city contact more accurately and comprehensively than the traditional gravity model, i.e., it yielded a higher adjusted R2 value(0.379) than the traditional gravity model result(0.259). Our study also suggests that, in addition to urban-regional and metropolitan development, the complementarities of the basic functions of cities at the administrative and market levels, as well as the corporeal and immaterial levels, play very significant roles in the characterization of city contact. Given the complexity of city contact, it will be necessary to consider more relevant influential factors in the modified gravity model to characterize the features of city contact in the future.
基金This work was part of an important project of Guangdong Province (No. 930816): On the impacts of sea level change and its countermeasures in Guangdong.
文摘By analysing comprehensively the factors such as theoretical sealevel, abnormal fluctuation of sea level, rising amplitude of floodtide water level and land deformation, a rising amplitude of 22-33 cm of relative sea level by the year of 2030 is forecasted in the Zhujiang Delta. From the forecasted amplitude of 30 cm, using hydraulic and hydrometric models the scope influenced by sea level rise is delimited and the reappearing periods of floodtide water level, protecting ability of embankments, design parameters of water conservancy project, drain waterlogging, saline intrusion, resource of mud beach and comprehensive prevention measures are discussed.
基金This thesis was funded by the American Wang'an Foundation.
文摘since 1978, rural urbanization has been accelerated in the Zhujiang (Pearl) River Delta because of the rapid development of commodity agriculture, industrialization and tertiary industry. Its natural urban population increase had been mostly mechanical before now, and the towns have been transformed from traditional centers into those serving various functions, particularly industrial ones.In the Zhujiang River Delta, population density and the level of economic changes are high in central areas, and low in outlying area, but on the other hand, urban population has increased slowly in central area and fast in outlying area. In the central areas more industrial towns emerge. So the gap has been greatly reduced. The reform of the construction of the region’s economy, the improvement of transportation, the adjustment of the standard of town setting have promoted the distribution of the towns in the Zhujiang River Delta from being centralized to balanced.
文摘A linear regression analysis of 28 selected tide-gauge stations of the Zhujiang Estuary shows that there has been a tendency of local sea level rise at a rate of 2.028 mm per year. The origin of the variation is significantly attributed to the local tectonic movement of discrepant fault-block. Based on this, four types of relative local sea level changes are classified. According to calculation, half of the fertile land, or 800 km2 of the delta plain will have been submerged by sea water by about 2040. This will yield a significant influence on the economic construction and human activities.
文摘The Zhujiang (Pearl) River Delta is the rapid economic development region in China since the opening and reform door policy was carried out in 1978. Being the rapid development of industry and city, the impact on the aquatic environmental quality was sig
基金Under the auspices of National High-tech Research and Development Program of China (863 Project) (No. 2006AA12Z207)
文摘The spatial distribution of meteorological elements is important for understanding the regional meteorology and climate changes. However,previous studies rarely focused on the daily changes of the spatial patterns of meteorological elements due to the limitation of remote sensing(RS) techniques and traditional meteorological methods. In this paper,the regional meteorological elements were simulated by the fifth-generation non-hydrostatic Mesoscale Model(MM5) ,and the spatial patterns of meteorological elements and their diurnal variations were analyzed in landscape level over the Pearl(Zhujiang) River Delta(PRD) ,China. The results showed that there were several centers of urban heat islands,cold islands,dry islands,wet islands,high wind over the PRD at noon. The diurnal changes of Moran I of meteorological elements were obvious and they reached the extremum at noon and 2-3 hours after the sunrise. The landscape indices of meteorological elements,such as area-weighted mean Fractal Dimension Index(FRAC_AM) ,Landscape Shape Index(LSI) ,Shannon's Diversity Index(SHDI) and Contagion Index(CONTAG) ,were more variable at about the sunrise,noon and sunset. The occurrence of wave crests and vales of landscape indices was affected by the surface net radiation,turbulence and local circumfluence. The spatial patterns of meteorological elements correlated well with the land surface,thermal exchanges and local circumfluence. A new approach combining GIS,RS and numerical simulations technologies and the landscape ecology method was presented to analyze spatial patterns of meteorological elements,which may be useful for studying global and regional climate changes.