2001年 第11卷 第1期
2001, 11(1): 1-10.
摘要:
In the last two decades, China has become one of the areas that have the greatest potential in industrial production, thus it has ranked second only to USA in the now of international capital. By the end of 1998, the real value of FDI (Foreign Direct Investment) in China has utilized has added up to $268. 1 billion. The big flow of FDI has not only promoted the development of social economy, but also worsened the existing regional difference by choosing spatial location. Under this circumstance, China's economy faces new restrictions and opportunities while adjusting its regional structure and industrial structure. So it is more and more important for us how to seize the opportunity, to seek the regUlarity of FDI in choosing location from the aspect Of space, to set up relevant strategy to direct FDI at inland regions (areas deficient of capital), and to make appropriate policies, esp. the industrial and regional policies so as for. FDI to exert positive influence and avoid negative influence on China and its regional economy and society. Based on the latest domestic and overseas materials and data of the FDI in China, combining with the investigation of the enterprises, this paper has systematically revealed the progress of development of the FDI in China and the developing conditions of the main enterprises directly invested by foreign capital since the reform and open-opening-up in China. The characters of FDI such as spatial concentration, transference as time goes on, change of the technical content and up-gradation of industrial structure and their forming mechanism have been studied. Then the basic conclusions have been made as follows. Firstly, FDI has been highly concentrated in space. But as time goes by, it has been transferring from coastal regions to inland ones, from big cities to their surrounding districts, and the degree of concentration is decreasing. Secondly, the technical content of the invested projects has gradually increased and the up-gradation of the industrial structure is obvious. Thirdly, the regional choice of the FDI in China is mainly affected by labor and other productive factors. The relative change of the cost of productive factors in different regions since the reform and opening-up is one of the main factors that have caused the spatial transference of the FDI in China. Fourthly, as people's income increases and the accumulation of the capacity of the technique and labor advances, FDI whose aim is to get more market has increased and tended to transfer from coastal regions to inland ones. Fifthly, the changes of the industrial structure of the main areas and countries who have directly invested in China and the changes of inter-regional industries and regional policies in China are also the important factors that affect the industries directly invested by foreign capital and their spatial transference.
In the last two decades, China has become one of the areas that have the greatest potential in industrial production, thus it has ranked second only to USA in the now of international capital. By the end of 1998, the real value of FDI (Foreign Direct Investment) in China has utilized has added up to $268. 1 billion. The big flow of FDI has not only promoted the development of social economy, but also worsened the existing regional difference by choosing spatial location. Under this circumstance, China's economy faces new restrictions and opportunities while adjusting its regional structure and industrial structure. So it is more and more important for us how to seize the opportunity, to seek the regUlarity of FDI in choosing location from the aspect Of space, to set up relevant strategy to direct FDI at inland regions (areas deficient of capital), and to make appropriate policies, esp. the industrial and regional policies so as for. FDI to exert positive influence and avoid negative influence on China and its regional economy and society. Based on the latest domestic and overseas materials and data of the FDI in China, combining with the investigation of the enterprises, this paper has systematically revealed the progress of development of the FDI in China and the developing conditions of the main enterprises directly invested by foreign capital since the reform and open-opening-up in China. The characters of FDI such as spatial concentration, transference as time goes on, change of the technical content and up-gradation of industrial structure and their forming mechanism have been studied. Then the basic conclusions have been made as follows. Firstly, FDI has been highly concentrated in space. But as time goes by, it has been transferring from coastal regions to inland ones, from big cities to their surrounding districts, and the degree of concentration is decreasing. Secondly, the technical content of the invested projects has gradually increased and the up-gradation of the industrial structure is obvious. Thirdly, the regional choice of the FDI in China is mainly affected by labor and other productive factors. The relative change of the cost of productive factors in different regions since the reform and opening-up is one of the main factors that have caused the spatial transference of the FDI in China. Fourthly, as people's income increases and the accumulation of the capacity of the technique and labor advances, FDI whose aim is to get more market has increased and tended to transfer from coastal regions to inland ones. Fifthly, the changes of the industrial structure of the main areas and countries who have directly invested in China and the changes of inter-regional industries and regional policies in China are also the important factors that affect the industries directly invested by foreign capital and their spatial transference.
2001, 11(1): 11-16.
摘要:
In the initial period of industrialization a great deal of land is needed for Chinese industry development as well as land resource per person of China is much lower than the average value in the world, thus it is necessary to save land in Chinese urban constrUction. This paper mainly discussed the features of urban land use in economic developed coastal cities: one is that the index of urban land per person in middle-small cities was higher than in large cities; another is that urban land has not been used highly and strongly; the third is that the industrial land occupied an irrationally large percentage of whole urban land; the final is that rural enterprises took up a quantity of land. Thereafter, this paper put forward five land-saving measures: first, to adopt the idea of saving land; next, to adjust the land-use structure when redeveloping the old city and alternate some land use when adjusting the industry structure of the city; the third, to develop the system of payment for using land and the management of urban planning; finally to enhance the effective regional plan and the urban landuse plan.
In the initial period of industrialization a great deal of land is needed for Chinese industry development as well as land resource per person of China is much lower than the average value in the world, thus it is necessary to save land in Chinese urban constrUction. This paper mainly discussed the features of urban land use in economic developed coastal cities: one is that the index of urban land per person in middle-small cities was higher than in large cities; another is that urban land has not been used highly and strongly; the third is that the industrial land occupied an irrationally large percentage of whole urban land; the final is that rural enterprises took up a quantity of land. Thereafter, this paper put forward five land-saving measures: first, to adopt the idea of saving land; next, to adjust the land-use structure when redeveloping the old city and alternate some land use when adjusting the industry structure of the city; the third, to develop the system of payment for using land and the management of urban planning; finally to enhance the effective regional plan and the urban landuse plan.
2001, 11(1): 17-26.
摘要:
The biggest change in Beijing during the last decade has been in its social structure. This transition is changing the existing situation of social "equality", and leads to polarization both in individual communities and in society as a whole. As a result, social variations and conflicting interest are growing, and some new social groups are emerging. In this paper we seek to exPlore a new urban Phenomenon in post-1984 Beijing: social polarization and segregation. At first, we will discuss some.elements explaining social polarization. The elements and the processes can be traced back to two main aspects of the economic reforms, namely the internal reforms unleashing a huge rural exodus and the open door policy. Special attention will be paid to the new lower end of the social ladder, which is made up largely by rural migrantsthat make up the so-called floating population. Finally we will explore how these social changes translate into urban segregation, with some consideration for future developments.
The biggest change in Beijing during the last decade has been in its social structure. This transition is changing the existing situation of social "equality", and leads to polarization both in individual communities and in society as a whole. As a result, social variations and conflicting interest are growing, and some new social groups are emerging. In this paper we seek to exPlore a new urban Phenomenon in post-1984 Beijing: social polarization and segregation. At first, we will discuss some.elements explaining social polarization. The elements and the processes can be traced back to two main aspects of the economic reforms, namely the internal reforms unleashing a huge rural exodus and the open door policy. Special attention will be paid to the new lower end of the social ladder, which is made up largely by rural migrantsthat make up the so-called floating population. Finally we will explore how these social changes translate into urban segregation, with some consideration for future developments.
2001, 11(1): 27-34.
摘要:
Natural environment, inland water distribution and water circulation has been changed greatly affected by human activities in Xinjiang, China. Human activities developed quickly in the inland watersheds in Xinjiang after 1950. More than 50% of river water is drawn into irrigation area, and all water in parts of little river is drawn to canal or reservoirs. However, there is evident hydrological effect caused by human activities. 1) water distribution in arid land has changed. A lot of river water is drawn into oasis and water table inside of oasis has risen but declined out of oasis. However, water table has declined in some cities because of over pumping for groundwater. 2) Stream process has changed after water drawing and drainage for irrigation. Runoff in the lower reaches of river has generally decreased, and the lower reaches of some rivers are even disappeared for stream. 3) Large watersheds have been divided into several small watersheds. In some tributaries, most of the river water has drawn to irrigation area so that stream in the lower reaches has disappeared for years. 4) Evaporation at oasis has increased from 50 - 200mm/a to 800 - 1300mm/a after reclamation. But it decreased to 50mm/a or less out of oasis. Some lakes have reduced or dried. Water system with canals and reservoirs has appeared in the oases. 5) Water quality of inland rivers and lakes has generally deteriorated because it accepts drainage water from farmland and factories. 6) Effective scale of human activities on hydrological process in arid land has expanded from separate rivers to all watersheds; from surface water to groundwater; from drought season to flood season; and from single year to several years. scale of the effect of human activities to hydrological pro- cess is going larger and larger. Along with the effective usage of water resources in the inland watershed in Xinjiang, the tydro- logical effect of human activities will be mainly change to: 1) river in pain area will be canalized; 2) stream process will be controlled by human being; 3)lakes in plain area will degenerate; 4) water will be salty in the lower reaches of river. How ever, hydrological condihons in Xinjiang will be better to water using and to natural environment.
Natural environment, inland water distribution and water circulation has been changed greatly affected by human activities in Xinjiang, China. Human activities developed quickly in the inland watersheds in Xinjiang after 1950. More than 50% of river water is drawn into irrigation area, and all water in parts of little river is drawn to canal or reservoirs. However, there is evident hydrological effect caused by human activities. 1) water distribution in arid land has changed. A lot of river water is drawn into oasis and water table inside of oasis has risen but declined out of oasis. However, water table has declined in some cities because of over pumping for groundwater. 2) Stream process has changed after water drawing and drainage for irrigation. Runoff in the lower reaches of river has generally decreased, and the lower reaches of some rivers are even disappeared for stream. 3) Large watersheds have been divided into several small watersheds. In some tributaries, most of the river water has drawn to irrigation area so that stream in the lower reaches has disappeared for years. 4) Evaporation at oasis has increased from 50 - 200mm/a to 800 - 1300mm/a after reclamation. But it decreased to 50mm/a or less out of oasis. Some lakes have reduced or dried. Water system with canals and reservoirs has appeared in the oases. 5) Water quality of inland rivers and lakes has generally deteriorated because it accepts drainage water from farmland and factories. 6) Effective scale of human activities on hydrological process in arid land has expanded from separate rivers to all watersheds; from surface water to groundwater; from drought season to flood season; and from single year to several years. scale of the effect of human activities to hydrological pro- cess is going larger and larger. Along with the effective usage of water resources in the inland watershed in Xinjiang, the tydro- logical effect of human activities will be mainly change to: 1) river in pain area will be canalized; 2) stream process will be controlled by human being; 3)lakes in plain area will degenerate; 4) water will be salty in the lower reaches of river. How ever, hydrological condihons in Xinjiang will be better to water using and to natural environment.
2001, 11(1): 35-41.
摘要:
The Longyangxia Gorge Key Water Control System is the first of the stairstep power sations along the Longyangxia-Qingtongxia river section. It has been playing an very important role in providing power, protecting flood and ice run supplying and irrigation etc. in the northwestem China. Therefore, the study on trend prediction, variation on the now into the Longyangxia Reservoir are of the great social and economic benefits. In the medium-and-long-range runoff forecast, all kinds of regression equation are often used for predicting future hydrologic regime. However, these regression models aren't appropriate to super long-range runoff forecast because of the restricting on weather data and so on. So a new super long-range runoff forecast model don't depend on Real-time weather data and called" Period correcting for residual error series GM(1,1) model" is presented based on analyzing for the relational hydrologic data and the variation on the now into the Longyangxia Reservoir, and the fore-cast model was applied successfully to predict the recent and super long-term trends of the flow into the Longyangxia Reservoir. The results indicate that the annual now into the Longyangxia Reservoir is in the ending minimum period of the runoff history. The runoff increasing is expected in for the coming years.
The Longyangxia Gorge Key Water Control System is the first of the stairstep power sations along the Longyangxia-Qingtongxia river section. It has been playing an very important role in providing power, protecting flood and ice run supplying and irrigation etc. in the northwestem China. Therefore, the study on trend prediction, variation on the now into the Longyangxia Reservoir are of the great social and economic benefits. In the medium-and-long-range runoff forecast, all kinds of regression equation are often used for predicting future hydrologic regime. However, these regression models aren't appropriate to super long-range runoff forecast because of the restricting on weather data and so on. So a new super long-range runoff forecast model don't depend on Real-time weather data and called" Period correcting for residual error series GM(1,1) model" is presented based on analyzing for the relational hydrologic data and the variation on the now into the Longyangxia Reservoir, and the fore-cast model was applied successfully to predict the recent and super long-term trends of the flow into the Longyangxia Reservoir. The results indicate that the annual now into the Longyangxia Reservoir is in the ending minimum period of the runoff history. The runoff increasing is expected in for the coming years.
2001, 11(1): 42-49.
摘要:
With the need in the global change research project for the land -use/land-cover change information, most international and regional research organization or groups have put amounts of efforts to improve of the dynamics monitoring and database updating techniques. With the pressure on nature environment from increasing population and decreasing farmland be- coming significant more and more in China, the farmland urban dynamics in historical and current times, even the change trends in the future, should be monitored and analyzed serving for regional and national social, economic and environmental sustain- able development in the long future. Based on spatial and temporal series of land -use/land-cover database resources, Chinese Academy of Sciences designed a sampling framework for monitoring farmland and urban area dynamics in regional and national level. In order to test the accuracy of the sampling schema for national and regional level, we took two provinces area into overall covered change detecting process with TM images data through being inter'Preted by digitalization on the screen. The result shows that our stratified random sampling schema is suitable for monitoring land -use/land-cover change at national and regional level with quick response, high accuracy and low expenses. The land-use/land-cover change (LUCC) information can update the LUTEA database for global change research during certain period so that the forecasting process and evaluating analysis on land resources and environment under human and natural driving force will get essential data and produce valuable conclusions.
With the need in the global change research project for the land -use/land-cover change information, most international and regional research organization or groups have put amounts of efforts to improve of the dynamics monitoring and database updating techniques. With the pressure on nature environment from increasing population and decreasing farmland be- coming significant more and more in China, the farmland urban dynamics in historical and current times, even the change trends in the future, should be monitored and analyzed serving for regional and national social, economic and environmental sustain- able development in the long future. Based on spatial and temporal series of land -use/land-cover database resources, Chinese Academy of Sciences designed a sampling framework for monitoring farmland and urban area dynamics in regional and national level. In order to test the accuracy of the sampling schema for national and regional level, we took two provinces area into overall covered change detecting process with TM images data through being inter'Preted by digitalization on the screen. The result shows that our stratified random sampling schema is suitable for monitoring land -use/land-cover change at national and regional level with quick response, high accuracy and low expenses. The land-use/land-cover change (LUCC) information can update the LUTEA database for global change research during certain period so that the forecasting process and evaluating analysis on land resources and environment under human and natural driving force will get essential data and produce valuable conclusions.
2001, 11(1): 50-56.
摘要:
Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 - 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements.
Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 - 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements.
2001, 11(1): 57-62.
摘要:
There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2.05×109m3/a that is 55.8% of the recharge. Thus the evapotranspiration discharge will reduce 60.4%, while spring water reducing 35. 6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0.55 in the future, the maximum safe yield of groundwater will reduce to 1.85×109m3/a with the recharge reducing to 3.1×109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In particular, protection of the glacier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical important and necessary.
There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2.05×109m3/a that is 55.8% of the recharge. Thus the evapotranspiration discharge will reduce 60.4%, while spring water reducing 35. 6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0.55 in the future, the maximum safe yield of groundwater will reduce to 1.85×109m3/a with the recharge reducing to 3.1×109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In particular, protection of the glacier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical important and necessary.
2001, 11(1): 63-69.
摘要:
The article analyzed the spatial division of industries of the Pearl River Delta (PRD) in the 1990s, a period that witnessed the deepening of the reform and opening policies and continued rapid development of the region. By adopting the index of specialization, the extent of specialization, its change and its spatial distribution in the region are measured and demonstrated. The research revealed that, despite the trend of more balanced development of the secondary sector between the PRD and the rest of the province, in the PRD, it is the unbalanced development that dominated and the spatial division of the secondary sector has been shaped. The tertian industry has also been experiencing unbalance development and the spatial division of the tertim sect been emerging, its extent of concentration appearing even more evident than that of the secondary sector. The author also discussed the linkage between the spatial division of the two sectors. In the end of the paper, the trends of the spatial division of the industries in the PRD are forecasted.
The article analyzed the spatial division of industries of the Pearl River Delta (PRD) in the 1990s, a period that witnessed the deepening of the reform and opening policies and continued rapid development of the region. By adopting the index of specialization, the extent of specialization, its change and its spatial distribution in the region are measured and demonstrated. The research revealed that, despite the trend of more balanced development of the secondary sector between the PRD and the rest of the province, in the PRD, it is the unbalanced development that dominated and the spatial division of the secondary sector has been shaped. The tertian industry has also been experiencing unbalance development and the spatial division of the tertim sect been emerging, its extent of concentration appearing even more evident than that of the secondary sector. The author also discussed the linkage between the spatial division of the two sectors. In the end of the paper, the trends of the spatial division of the industries in the PRD are forecasted.
2001, 11(1): 70-75.
摘要:
Yanji is the biggest China Korean inhabited city. Based on a newly finished research project, this paper discusses strategic problems about Yanji towards 21st century. The general point of the authors is that at the beginning of new century, Yanji will play a more important role in Tumen River Delta development, regional economy cooperation in Korea Peninsula as well as Northeast Asia, and it will develop to be an important central city in this area. This paper puts forwards Yanji City's developing goal, urban nature, and urban size, probes its regional orientation, and further probes how to establish The Yanji Urban Economy Cooperation Zone. The authors think that Yanji should depend on its intellect resources and other characteristic resources. Industry development need to pay much attention to modern agriculture, teltiary industry (especially commerce, trade and tourism) and dominant industries, and high-tech industry must give a special care, in order to establish a light industrial structure.
Yanji is the biggest China Korean inhabited city. Based on a newly finished research project, this paper discusses strategic problems about Yanji towards 21st century. The general point of the authors is that at the beginning of new century, Yanji will play a more important role in Tumen River Delta development, regional economy cooperation in Korea Peninsula as well as Northeast Asia, and it will develop to be an important central city in this area. This paper puts forwards Yanji City's developing goal, urban nature, and urban size, probes its regional orientation, and further probes how to establish The Yanji Urban Economy Cooperation Zone. The authors think that Yanji should depend on its intellect resources and other characteristic resources. Industry development need to pay much attention to modern agriculture, teltiary industry (especially commerce, trade and tourism) and dominant industries, and high-tech industry must give a special care, in order to establish a light industrial structure.
2001, 11(1): 76-79.
摘要:
This paper takes marsh in the Sanjiang Plain as an example in order to research the effect of draining on the chemical elements in marsh. The Sanjiang Ecological Test Station of Mire and Uetland serves as the resarch base. The authors selected soil samples in the Sanjiang Plain (the top and the end of the drain, marsh soil and degeneration marsh soil), mainly analyzed contents of main ions (HCO3-, Cl-, SO42- and NO3- ), main heavy metals (Fe, Mn, Zn and Cu), nutritive elements (N, P, K), organic matter and pH value. By testing these samples as above, the paper initially researches the effect on chemical ele- ments content by draining by the means of the contrast of chemical elements contents between marsh soil and degenetative marsh soil and different characteristics of marsh soil elements. Results show that a lot of chemical elements had been lost because of draining.
This paper takes marsh in the Sanjiang Plain as an example in order to research the effect of draining on the chemical elements in marsh. The Sanjiang Ecological Test Station of Mire and Uetland serves as the resarch base. The authors selected soil samples in the Sanjiang Plain (the top and the end of the drain, marsh soil and degeneration marsh soil), mainly analyzed contents of main ions (HCO3-, Cl-, SO42- and NO3- ), main heavy metals (Fe, Mn, Zn and Cu), nutritive elements (N, P, K), organic matter and pH value. By testing these samples as above, the paper initially researches the effect on chemical ele- ments content by draining by the means of the contrast of chemical elements contents between marsh soil and degenetative marsh soil and different characteristics of marsh soil elements. Results show that a lot of chemical elements had been lost because of draining.
2001, 11(1): 80-86.
摘要:
The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air temperature about- 5.6℃. The common 14C and AMS 14C dating ages of terrestrial branch relicts in Huahai clay-mirabilite interlayer are (11600± 280) a B. P. and (1118±54) a B. P. respectively, proving that the drirabilite formed at the cold episode of the Last Glacial Maximum(LGM) and Younger Dryers (YD) in Huahai Lake. It is pointed out that the mean annual air temperature in Hexi Corridor during LGM was about - 3℃ - - 7℃, 11℃-15℃ lower than that of present, and that during YD was about 0℃-2℃, 6℃-8℃ lower than at present. This decreasing temperature values are generally coincident with those inferred by pollen, sand wedge and ice core in the northern China, and also with the research on temperature-falling amplitude of middle and high latitude on the Northern Hemisphere recently.
The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air temperature about- 5.6℃. The common 14C and AMS 14C dating ages of terrestrial branch relicts in Huahai clay-mirabilite interlayer are (11600± 280) a B. P. and (1118±54) a B. P. respectively, proving that the drirabilite formed at the cold episode of the Last Glacial Maximum(LGM) and Younger Dryers (YD) in Huahai Lake. It is pointed out that the mean annual air temperature in Hexi Corridor during LGM was about - 3℃ - - 7℃, 11℃-15℃ lower than that of present, and that during YD was about 0℃-2℃, 6℃-8℃ lower than at present. This decreasing temperature values are generally coincident with those inferred by pollen, sand wedge and ice core in the northern China, and also with the research on temperature-falling amplitude of middle and high latitude on the Northern Hemisphere recently.
2001, 11(1): 87-91.
摘要:
Numerous studies indicated that aluminum, the most abundant metallic element within the lithosphere, was consid- ered to be related to some human diseases especially the Alzheimer's disease. Tea, economically an important beverage in the world, has been found to contain higher concentration of aluminum than many other drinks and foods. Therefore, tea would be a potentially important source of dietary aluminum. In order to understand the sources of aluminum in tea leaves and factors related with aluminum content of tea leaves, an experiment was designed to investigate the relationships of aluminum in tea leaves with leaf age, soil properties and forms of aluminum in soils. The results showed that there were great distinctions in the concentration of aluminum in tea leaves with different leaf age (Alold leaf >Almature leaf> Alyoung leaf). Moreover, soil pH was the major factor controlling the uptake of aluminum from soil into tea leaves. Fnrthermore, the content of aluminum in tea leaves was better predicated by the soluble aluminum extracted by 0. 02mol/L CaCl2.
Numerous studies indicated that aluminum, the most abundant metallic element within the lithosphere, was consid- ered to be related to some human diseases especially the Alzheimer's disease. Tea, economically an important beverage in the world, has been found to contain higher concentration of aluminum than many other drinks and foods. Therefore, tea would be a potentially important source of dietary aluminum. In order to understand the sources of aluminum in tea leaves and factors related with aluminum content of tea leaves, an experiment was designed to investigate the relationships of aluminum in tea leaves with leaf age, soil properties and forms of aluminum in soils. The results showed that there were great distinctions in the concentration of aluminum in tea leaves with different leaf age (Alold leaf >Almature leaf> Alyoung leaf). Moreover, soil pH was the major factor controlling the uptake of aluminum from soil into tea leaves. Fnrthermore, the content of aluminum in tea leaves was better predicated by the soluble aluminum extracted by 0. 02mol/L CaCl2.
2001, 11(1): 92-96.
摘要:
Studying the evolution of groundwater pollutants and the causes of formation in Manzhouli is important and necessitous as the present water source of the production and living in Manzhouli is just groundwater and the water crisis is staring Manzhouli people in the face. The evolution of pollutants in groundwater in Manzhouli was derived based on the continuously monitoring between 1989 and 1999. In total, the quality of groundwater in Manzhouli is good except that the content of F is exceeding the standard. The quality of groundwater varies seasonally. The content of pollutants in high water is higher than in the low water except pH and As. The yearly evolution shows the regime like the damp surge. The evolution of pH is inverse to NO3-N and F after 1999. The courses of formation of the evolution of the content of the pollutants in groundwater in Manzhouli are the supply of runoff, the feature of rock, the time the water being stayed in the layers and the chemical field. Being affected by the supply of ground surface and hydrogeology condition, the contents of pollutant are higher in the May than in September and the yearly evolution is undulance. In total, the pollutants in the deeper layers are less than in the upper layers. Explosion water in the deeper layers, using the techniques of cutting F and minifying the pollutants caused by human being are the sound countermeasures in Manzhouli.
Studying the evolution of groundwater pollutants and the causes of formation in Manzhouli is important and necessitous as the present water source of the production and living in Manzhouli is just groundwater and the water crisis is staring Manzhouli people in the face. The evolution of pollutants in groundwater in Manzhouli was derived based on the continuously monitoring between 1989 and 1999. In total, the quality of groundwater in Manzhouli is good except that the content of F is exceeding the standard. The quality of groundwater varies seasonally. The content of pollutants in high water is higher than in the low water except pH and As. The yearly evolution shows the regime like the damp surge. The evolution of pH is inverse to NO3-N and F after 1999. The courses of formation of the evolution of the content of the pollutants in groundwater in Manzhouli are the supply of runoff, the feature of rock, the time the water being stayed in the layers and the chemical field. Being affected by the supply of ground surface and hydrogeology condition, the contents of pollutant are higher in the May than in September and the yearly evolution is undulance. In total, the pollutants in the deeper layers are less than in the upper layers. Explosion water in the deeper layers, using the techniques of cutting F and minifying the pollutants caused by human being are the sound countermeasures in Manzhouli.
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