1998年 第8卷 第3期
1998, 8(3): 193-203.
摘要:
Population density in Guangzhou City is characterized by a main single center and considerable differences throughout the 8 districts and 112 neighborhoods and towns. Historically, population density in Guangzhou City rose sharply, and population distribution was mainly influenced by the attraction of the port. After the founding of the People's Republic of China (PRC), a series of large sized factories were built in suburban areas, which drew in a large amount of population from the areas outside of Guangzhou. A small part of this population lived in the suburban areas while most resided within the city centre. As the natural increase rate of population was very high, the population density of both the city centre and suburban areas rose, the former rose at higher rates. Since reform and the opening up to the outside world, Chinese economy has grown quickly, the total population of Guangzhou has also increased quickly. Meanwhile, changes in population density within the city is becoming more and more obvious. Population density in the city centre is falling and in city periphery is rising. From the analysis of the population density model, it is found that population distribution of Guangzhou is in the process of transition from an early stage to a mature stage. Population decline within the centre city of Guangzhou City, which reflects a prosperous economy of the city, is significantly different from the recession of in the western countries.
Population density in Guangzhou City is characterized by a main single center and considerable differences throughout the 8 districts and 112 neighborhoods and towns. Historically, population density in Guangzhou City rose sharply, and population distribution was mainly influenced by the attraction of the port. After the founding of the People's Republic of China (PRC), a series of large sized factories were built in suburban areas, which drew in a large amount of population from the areas outside of Guangzhou. A small part of this population lived in the suburban areas while most resided within the city centre. As the natural increase rate of population was very high, the population density of both the city centre and suburban areas rose, the former rose at higher rates. Since reform and the opening up to the outside world, Chinese economy has grown quickly, the total population of Guangzhou has also increased quickly. Meanwhile, changes in population density within the city is becoming more and more obvious. Population density in the city centre is falling and in city periphery is rising. From the analysis of the population density model, it is found that population distribution of Guangzhou is in the process of transition from an early stage to a mature stage. Population decline within the centre city of Guangzhou City, which reflects a prosperous economy of the city, is significantly different from the recession of in the western countries.
1998, 8(3): 204-211.
摘要:
The crop estimates by remote sensing, developing quickly in recent decades, is a up to date technique. Regionalization for large area crop estimates by remote sensing, a special applied regionalization, is the foundation of crop estimates in a large area by remote sensing. According to the actual demands of wheat yield estimation by remote sensing and wheat agroclimatic demarcation of China, this paper first puts forward some principles upheld in this regionalization and analyses its main bases. Secondly, it works out the classificatory schemes about the optimum temporal for estimating wheat yield by remote sensing, information sources of space remote sensing and landuse structure in China. Finally, According to the regionalization indices, this study divides the wheat plantable region of China into 14 regions of crop yield estimates and 31 subregions of crop yield estimates.
The crop estimates by remote sensing, developing quickly in recent decades, is a up to date technique. Regionalization for large area crop estimates by remote sensing, a special applied regionalization, is the foundation of crop estimates in a large area by remote sensing. According to the actual demands of wheat yield estimation by remote sensing and wheat agroclimatic demarcation of China, this paper first puts forward some principles upheld in this regionalization and analyses its main bases. Secondly, it works out the classificatory schemes about the optimum temporal for estimating wheat yield by remote sensing, information sources of space remote sensing and landuse structure in China. Finally, According to the regionalization indices, this study divides the wheat plantable region of China into 14 regions of crop yield estimates and 31 subregions of crop yield estimates.
1998, 8(3): 212-224.
摘要:
This paper presents a new perspective on the nature of destination competition in spatial interaction models. The concept of destinations competing with one another on the basis of their spatial proximity to each other is compared with an alternative point of view which argues that competition takes place on the basis of similarities in the spatial influences of competing destinations on decision makers at origins. Potential movers at an origin are facing a set of destinations which compete for their attention. This paper argues that the movers' choices are conditioned by the relative size and number of influences they see (where influence is directly proportional to destination size and inversely proportional to distance). A small amount of supporting empirical evidence concerning recreational day trips, and population migration, is presented.
This paper presents a new perspective on the nature of destination competition in spatial interaction models. The concept of destinations competing with one another on the basis of their spatial proximity to each other is compared with an alternative point of view which argues that competition takes place on the basis of similarities in the spatial influences of competing destinations on decision makers at origins. Potential movers at an origin are facing a set of destinations which compete for their attention. This paper argues that the movers' choices are conditioned by the relative size and number of influences they see (where influence is directly proportional to destination size and inversely proportional to distance). A small amount of supporting empirical evidence concerning recreational day trips, and population migration, is presented.
1998, 8(3): 225-231.
摘要:
In the paper 11 pollen types were selected from the original pollen and spore records of 54 samples in Fenzhuang profile of Beijing region, then 54×11 matrix was set up. Based on the pollen data of Fenzhuang profile from the Late Pleistocene to the Early Holocene, the paper gives a further analysis to subdivide zone of the pollen assemblages and changes of paleovegetation and paleoenvironment in this area using principal component analysis (PCA). PCA can play an complementary role for subdividing zone, at the same time, it can eliminate the difference to subdivide zone of the pollen assemblages caused by artificial factors. Finally to the biodiversity in plant communities and complex geographical environment in Beijing region, using great dispersal of accumulative percent of total in PCA (for cumulative rate only 57% from the first three factors of PCA), may sufficiently correspond to the environmental characteristic, so as to recover past climate condition much better.
In the paper 11 pollen types were selected from the original pollen and spore records of 54 samples in Fenzhuang profile of Beijing region, then 54×11 matrix was set up. Based on the pollen data of Fenzhuang profile from the Late Pleistocene to the Early Holocene, the paper gives a further analysis to subdivide zone of the pollen assemblages and changes of paleovegetation and paleoenvironment in this area using principal component analysis (PCA). PCA can play an complementary role for subdividing zone, at the same time, it can eliminate the difference to subdivide zone of the pollen assemblages caused by artificial factors. Finally to the biodiversity in plant communities and complex geographical environment in Beijing region, using great dispersal of accumulative percent of total in PCA (for cumulative rate only 57% from the first three factors of PCA), may sufficiently correspond to the environmental characteristic, so as to recover past climate condition much better.
1998, 8(3): 232-238.
摘要:
Qinghai Lake is located in the northeastern Qinghai Xizang(Tibet) Plateau. It is an especially big light saltwater lake. The mire meadow in Qinghai Lake drainage area is an eco system which is affected by the eco environment factors. Its formation, development and temporal and spatial distribution law are decided by a few main meteorological factors in the eco environment to a certain extent. The main meteorological factors are ≥10℃ accumulated temperature, precipitation from May to September and annual humidity coefficient. The mathematical model of the mire wetland rate and the main meteorological factors is given by multivariate linear regression in the paper.
Qinghai Lake is located in the northeastern Qinghai Xizang(Tibet) Plateau. It is an especially big light saltwater lake. The mire meadow in Qinghai Lake drainage area is an eco system which is affected by the eco environment factors. Its formation, development and temporal and spatial distribution law are decided by a few main meteorological factors in the eco environment to a certain extent. The main meteorological factors are ≥10℃ accumulated temperature, precipitation from May to September and annual humidity coefficient. The mathematical model of the mire wetland rate and the main meteorological factors is given by multivariate linear regression in the paper.
1998, 8(3): 239-245.
摘要:
The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and economic development in the Tumen River basin. Pollutant type and primary pollution factor of the Tumen River in Northeast China is described by weighted coefficient method in this paper. The results indicate that the river is organic pollution type and primary pollution factor is COD. Fresh water fraction proves that the estuary is not affected by tide cycle. COD annual flux entering the Sea of Japan calculated by zero dimension model in 1993 was 90.50 ×103 tons. It is estimated with emission coefficient method that the COD will be 176.4 ×103 and 458.6 ×103 tons for the years of 2000 and 2010 respectively.
The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and economic development in the Tumen River basin. Pollutant type and primary pollution factor of the Tumen River in Northeast China is described by weighted coefficient method in this paper. The results indicate that the river is organic pollution type and primary pollution factor is COD. Fresh water fraction proves that the estuary is not affected by tide cycle. COD annual flux entering the Sea of Japan calculated by zero dimension model in 1993 was 90.50 ×103 tons. It is estimated with emission coefficient method that the COD will be 176.4 ×103 and 458.6 ×103 tons for the years of 2000 and 2010 respectively.
1998, 8(3): 246-255.
摘要:
Soil respiration is CO2 evolution process from soil to atmosphere, mainly produced by soil micro organism and plant roots. It is affected not only by biological factors (vegetation, micro organism, etc.) and environmental factors (temperature, moisture, pH, etc.), but also more and more strongly by man made factors. Based on literature survey, main factors affecting soil respiration were reviewed. The relationships of soil respiration to latitude and to mean annual temperature were analyzed by using the data measured from forest vegetation in the world. As a result, soil respiration rate decreased exponentially with an increase of latitude, and increased with increasing temperature. Following the relationship between soil respiration and temperature, Q10 value (law of Van Hoff) was obtained as 1.57 in the global scale.
Soil respiration is CO2 evolution process from soil to atmosphere, mainly produced by soil micro organism and plant roots. It is affected not only by biological factors (vegetation, micro organism, etc.) and environmental factors (temperature, moisture, pH, etc.), but also more and more strongly by man made factors. Based on literature survey, main factors affecting soil respiration were reviewed. The relationships of soil respiration to latitude and to mean annual temperature were analyzed by using the data measured from forest vegetation in the world. As a result, soil respiration rate decreased exponentially with an increase of latitude, and increased with increasing temperature. Following the relationship between soil respiration and temperature, Q10 value (law of Van Hoff) was obtained as 1.57 in the global scale.
1998, 8(3): 256-263.
摘要:
Eight spatial structure types are determined through morphology, hydrogeology, hydrology and impulse response in karst districts, with the well studied Houzhai subterranean stream in Puding, Guizhou Province as a sample research area. These types contain peak forest basin, peak forest laterite platform, resurrected peak forest basin, old peak forest funnel depression, peak forest funnel, peak forest funnel depression, peak cluster valley and peak forest doline. In the area, each of them has its respective surface and subterranean structural feature, and morphology, hydrogeology, hydrology and impulse response as well. The difference of responses of subsurface system in different spatial structure types are obtained by time series analysis, frequency spectrum research and decline curve calculation of material current. According to the analysis of the aquifer feature, the upper reaches of suburfall stream is dominated by pipeline flow, the lower reaches is characterized by braided fissure flow drainage system and mixed characteristic exists in the middle reaches. The result of the impulse test shows that the large ascending range of stage in the test on swash condition is in fissure system. However, in pipeline type, especially in the subterranean stream where there is waterfall or incomplete fill of underground water, the ascending range of stage is one quantity level less than the impulse range of stage at some fissure types, showing that change range of stage can indicate the spatial structure characteristics of certain area upper the station. The main direction of karst geomorphic evolution there is positive course except in the west area. It can be seen that karst geomorphological evolution direction can change when discharge datum plane influences some part of a relatively large drainage. In certain time unit, the upper reaches are controlled by old datum plane and the lower reaches by new datum plane. Two opposite geomorphological evolution directions can exist in one drainage.
Eight spatial structure types are determined through morphology, hydrogeology, hydrology and impulse response in karst districts, with the well studied Houzhai subterranean stream in Puding, Guizhou Province as a sample research area. These types contain peak forest basin, peak forest laterite platform, resurrected peak forest basin, old peak forest funnel depression, peak forest funnel, peak forest funnel depression, peak cluster valley and peak forest doline. In the area, each of them has its respective surface and subterranean structural feature, and morphology, hydrogeology, hydrology and impulse response as well. The difference of responses of subsurface system in different spatial structure types are obtained by time series analysis, frequency spectrum research and decline curve calculation of material current. According to the analysis of the aquifer feature, the upper reaches of suburfall stream is dominated by pipeline flow, the lower reaches is characterized by braided fissure flow drainage system and mixed characteristic exists in the middle reaches. The result of the impulse test shows that the large ascending range of stage in the test on swash condition is in fissure system. However, in pipeline type, especially in the subterranean stream where there is waterfall or incomplete fill of underground water, the ascending range of stage is one quantity level less than the impulse range of stage at some fissure types, showing that change range of stage can indicate the spatial structure characteristics of certain area upper the station. The main direction of karst geomorphic evolution there is positive course except in the west area. It can be seen that karst geomorphological evolution direction can change when discharge datum plane influences some part of a relatively large drainage. In certain time unit, the upper reaches are controlled by old datum plane and the lower reaches by new datum plane. Two opposite geomorphological evolution directions can exist in one drainage.
1998, 8(3): 264-270.
摘要:
In order to the quickly update land cover information and improve the survey accuracy, the land covers of northeast China were manually interpreted and mapped by using over 60 Land sat Thematic Mapped (TM) images and other information sources, then the interpreted land cover maps were digitally entered into computers to form GIS. Under the GIS circumstances, the data were processed and calculated to draw out the area. Meanwhile, area proportion of small objects were estimated by means of sampling, this improved the survey accuracy.
In order to the quickly update land cover information and improve the survey accuracy, the land covers of northeast China were manually interpreted and mapped by using over 60 Land sat Thematic Mapped (TM) images and other information sources, then the interpreted land cover maps were digitally entered into computers to form GIS. Under the GIS circumstances, the data were processed and calculated to draw out the area. Meanwhile, area proportion of small objects were estimated by means of sampling, this improved the survey accuracy.
1998, 8(3): 271-280.
摘要:
This paper focuses on migration occurrence as a result of environmental degradation and population growth. It briefly reviews previous practices in some less developed courtries and then considers the extent to which environmental factors have been and may be significant in initiating migration. A case study of the karst region of southwest China is used to illustrate the phenomenon, including root causes, restrictive factors, nature of the migration, desires of migrants, strategies of response and optional policies. It is argued that a comprehensive approach to the prevention of environmentally caused displacement should be developed.
This paper focuses on migration occurrence as a result of environmental degradation and population growth. It briefly reviews previous practices in some less developed courtries and then considers the extent to which environmental factors have been and may be significant in initiating migration. A case study of the karst region of southwest China is used to illustrate the phenomenon, including root causes, restrictive factors, nature of the migration, desires of migrants, strategies of response and optional policies. It is argued that a comprehensive approach to the prevention of environmentally caused displacement should be developed.
1998, 8(3): 281-288.
摘要:
Wetland is a special ecological system in the earth, which can provide a good habitat for many wild animals. It is a reproduction and overwintering area for many rare waterfowls, too. The northeast region, including Heilongjiang, Jilin, Liaoning provinces, and the east of Inner Mongolia, is a district with the maximum areas and types of wetlands in China. It is the center of the waterfowls reproduction in Northeast Asia and the necessary region moving to the south. The conservation of wetland and waterfowls habitats in northeast China plays an important role in international waterfowls habitats conservation. The northeast weterfowls' types, number and distribution specific features are studied in three aspects in the paper, so do the rare waterfowls. Existing problems and the administration polices on waterfowls and their habitats conservation in the northeast are also discussed. It shows that the conservation of wetland waterfowls habitats in northeast China is important.
Wetland is a special ecological system in the earth, which can provide a good habitat for many wild animals. It is a reproduction and overwintering area for many rare waterfowls, too. The northeast region, including Heilongjiang, Jilin, Liaoning provinces, and the east of Inner Mongolia, is a district with the maximum areas and types of wetlands in China. It is the center of the waterfowls reproduction in Northeast Asia and the necessary region moving to the south. The conservation of wetland and waterfowls habitats in northeast China plays an important role in international waterfowls habitats conservation. The northeast weterfowls' types, number and distribution specific features are studied in three aspects in the paper, so do the rare waterfowls. Existing problems and the administration polices on waterfowls and their habitats conservation in the northeast are also discussed. It shows that the conservation of wetland waterfowls habitats in northeast China is important.
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