2007年 第17卷 第4期
2007, 17(4): 289-296.
doi: 10.1007/s11769-007-0289-1
摘要:
Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development between land use and PRED system. Based on the internal relationship between land use and PRED system, a PRED evaluation index system and a Press-Status-Response (PSR) model were established in this study. According to the expounding on the mechanism of the PSR model, we investigated the coordinative development between the changes of regional land use and PRED system taking Jiangsu Province as an example. The results showed that the orders of the Synthetic Index of Land Use (SILU) and the Variation of PRED Index (VPI) in Jiangsu are both the southern Jiangsu>the central Jiangsu>the northern Jiangsu. A cubic curve model was used to fit the relationship between the VPI and SILU. The inflection point of VPI was situated in 5.0 of SILU. When SILU was below 5.0, VPI increased with SILU, which will be helpful to the coordinative development between land use and PRED system. Based on those results, it is suggested that the land use degree of the southern Jiangsu, especially that of Nanjing City, should be moderately controlled at present, while land resources of the central Jiangsu and the northern Jiangsu should be further exploited.
Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development between land use and PRED system. Based on the internal relationship between land use and PRED system, a PRED evaluation index system and a Press-Status-Response (PSR) model were established in this study. According to the expounding on the mechanism of the PSR model, we investigated the coordinative development between the changes of regional land use and PRED system taking Jiangsu Province as an example. The results showed that the orders of the Synthetic Index of Land Use (SILU) and the Variation of PRED Index (VPI) in Jiangsu are both the southern Jiangsu>the central Jiangsu>the northern Jiangsu. A cubic curve model was used to fit the relationship between the VPI and SILU. The inflection point of VPI was situated in 5.0 of SILU. When SILU was below 5.0, VPI increased with SILU, which will be helpful to the coordinative development between land use and PRED system. Based on those results, it is suggested that the land use degree of the southern Jiangsu, especially that of Nanjing City, should be moderately controlled at present, while land resources of the central Jiangsu and the northern Jiangsu should be further exploited.
2007, 17(4): 297-303.
doi: 10.1007/s11769-007-0297-1
摘要:
The investment of Samsung Electronics in China is divided into three types: production companies, sales companies and R&D institutions. Based on an analysis of the spatial structure of Samsung's three types of investment and parent company, it is put forward that regional bias exists during the operation of a multi-national corporation (MNC) in China, i.e., regional biases of technology, price, sales as well as decision-making. Front office and back office, two terms related closely with the location of modern MNCs, are defined and locational principles of each are studied. It is pointed out that production companies and R&D institutions belong to back office, while sales company falls into the type of front office. Based on a summarization on the spatial distribution of production companies, sales companies and R&D institutions, the locational principles of front office and back office are then applied in explaining the location of Samsung's operating entities in China. By analyzing the spatial structure and locational principles of Samsung, a typical MNC in China, this paper aims to understand the internal operating mechanism of modern MNCs and then bring assistance to related policies to cope with those problems about MNCs that have attracted growing attention in recent years.
The investment of Samsung Electronics in China is divided into three types: production companies, sales companies and R&D institutions. Based on an analysis of the spatial structure of Samsung's three types of investment and parent company, it is put forward that regional bias exists during the operation of a multi-national corporation (MNC) in China, i.e., regional biases of technology, price, sales as well as decision-making. Front office and back office, two terms related closely with the location of modern MNCs, are defined and locational principles of each are studied. It is pointed out that production companies and R&D institutions belong to back office, while sales company falls into the type of front office. Based on a summarization on the spatial distribution of production companies, sales companies and R&D institutions, the locational principles of front office and back office are then applied in explaining the location of Samsung's operating entities in China. By analyzing the spatial structure and locational principles of Samsung, a typical MNC in China, this paper aims to understand the internal operating mechanism of modern MNCs and then bring assistance to related policies to cope with those problems about MNCs that have attracted growing attention in recent years.
2007, 17(4): 304-310.
doi: 10.1007/s11769-007-0304-6
摘要:
Sustainable development is a complex and systemic issue. It is essential to study it by the component analysis method from the view of system science. The urban developmental sustainability is one of focuses that people has paid more attention to, however, little common understanding how to measure and evaluate the sustainability has been gotten. In this paper, a framework is designed to evaluate the developmental sustainability of Suihua City, Heilongjiang Province in China from the aspects of economy, society, population, resources and environment. We adopt the Principal Components Analysis (PCA) to decrease dimensions and simplify the original indexes into 12 indexes. Also, the hierarchy and comprehensive multiple-criterion evaluative methods are employed to assess the sustainable development system in Suihua City. Then, the weights of indexes are attained by Analytic Hierarchy Process (AHP) method. Furthermore, urban comprehensive development level, developmental sustainability, coordinate degree are calculated and analyzed. By analyzing, we know the fluctuation of development level of subsystem, especially resources and environment subsystem, is acute. The comprehensive development level of sustainable development system in Suihua has been on the rise since 1999. That results from the effect of traditional economic development mode with high energy-consumed being decreased in the city after 1999. At the same time, it is obvious that there was an instability of development level in Suihua City during 1990–2002, with a turn in 1998, and the development could be sustainable, the status trend was more harmonious in 1999–2002.
Sustainable development is a complex and systemic issue. It is essential to study it by the component analysis method from the view of system science. The urban developmental sustainability is one of focuses that people has paid more attention to, however, little common understanding how to measure and evaluate the sustainability has been gotten. In this paper, a framework is designed to evaluate the developmental sustainability of Suihua City, Heilongjiang Province in China from the aspects of economy, society, population, resources and environment. We adopt the Principal Components Analysis (PCA) to decrease dimensions and simplify the original indexes into 12 indexes. Also, the hierarchy and comprehensive multiple-criterion evaluative methods are employed to assess the sustainable development system in Suihua City. Then, the weights of indexes are attained by Analytic Hierarchy Process (AHP) method. Furthermore, urban comprehensive development level, developmental sustainability, coordinate degree are calculated and analyzed. By analyzing, we know the fluctuation of development level of subsystem, especially resources and environment subsystem, is acute. The comprehensive development level of sustainable development system in Suihua has been on the rise since 1999. That results from the effect of traditional economic development mode with high energy-consumed being decreased in the city after 1999. At the same time, it is obvious that there was an instability of development level in Suihua City during 1990–2002, with a turn in 1998, and the development could be sustainable, the status trend was more harmonious in 1999–2002.
2007, 17(4): 311-316.
doi: 10.1007/s11769-007-0311-7
摘要:
From the viewpoint of Graph Theory this paper builds a town road network graph of regional scale, and proposes numerical vertex degree (Di), rank vertex degree (Dr) and population size vertex degree (Dp) on the base of vertex degree (D). Then the indicators of Di, Dr, Dp and mathematical statistics methods are applied to investigating scale-free structure of town road networks in the southern Jiangsu Province. The results show that the distribution of Di does not exhibit scale-free properties, but Dr and Dp do. Additionally the correlation coefficient between Dp and Di is only 0.569, but the spatial correlation between Dp and Dr is very evident on the base of correlation analysis and spatial analysis of GIS. The mutual mechanism between Dp and Dr spatially represents a "Core-Belt" model of town development of regional scale. The town development model is open and clustered, and beneficial to both economic development and ecological protection. And then we suggest that Suzhou City, Wuxi City, Changzhou City and Wujin City control towns' high-density pattern by conducting centralization and consolidation policies, and properly controlling and planning higher rank roads; whereas Nanjing City, Zhenjiang City, Jintan City and Liyang City must strengthen the development of towns along higher rank roads.
From the viewpoint of Graph Theory this paper builds a town road network graph of regional scale, and proposes numerical vertex degree (Di), rank vertex degree (Dr) and population size vertex degree (Dp) on the base of vertex degree (D). Then the indicators of Di, Dr, Dp and mathematical statistics methods are applied to investigating scale-free structure of town road networks in the southern Jiangsu Province. The results show that the distribution of Di does not exhibit scale-free properties, but Dr and Dp do. Additionally the correlation coefficient between Dp and Di is only 0.569, but the spatial correlation between Dp and Dr is very evident on the base of correlation analysis and spatial analysis of GIS. The mutual mechanism between Dp and Dr spatially represents a "Core-Belt" model of town development of regional scale. The town development model is open and clustered, and beneficial to both economic development and ecological protection. And then we suggest that Suzhou City, Wuxi City, Changzhou City and Wujin City control towns' high-density pattern by conducting centralization and consolidation policies, and properly controlling and planning higher rank roads; whereas Nanjing City, Zhenjiang City, Jintan City and Liyang City must strengthen the development of towns along higher rank roads.
2007, 17(4): 317-324.
doi: 10.1007/s11769-007-0317-1
摘要:
The northeastern China is a sensitive region of climate change, whose detailed trend of climate changes is highly interesting. In this study, this kind of variation trend was analyzed. Potential evapotranspiration (PE) and moisture index (MI) were modeled by using Thornthwaite scheme based on the observation data of 1961–2004 from 94 meteorological stations. To describe the climate fluctuation in the northeastern China in 1961–2004, the linear regression method was used to analyze the variation trends of mean annual temperature, mean annual precipitation, PE and MI. Mann-Kendall method was used to test the significant difference. The results show a general increasing tendency in mean annual temperature, mean annual precipitation, PE and MI. However increasing tendency was more significant in mean annual temperature and PE than in mean annual precipitation and MI. Analysis of seasonal climate variation indicates that there showed positive trends in winter and in spring, while the positive trend was more significant in winter than in spring. Furthermore, the relations between climate changes and geographical factors were analyzed, the results show that both climate factors and their interannual variability were correlated to latitude, longitude and altitude, suggesting that latitude is the most climate factor affecting climate changes, followed by altitude and longitude.
The northeastern China is a sensitive region of climate change, whose detailed trend of climate changes is highly interesting. In this study, this kind of variation trend was analyzed. Potential evapotranspiration (PE) and moisture index (MI) were modeled by using Thornthwaite scheme based on the observation data of 1961–2004 from 94 meteorological stations. To describe the climate fluctuation in the northeastern China in 1961–2004, the linear regression method was used to analyze the variation trends of mean annual temperature, mean annual precipitation, PE and MI. Mann-Kendall method was used to test the significant difference. The results show a general increasing tendency in mean annual temperature, mean annual precipitation, PE and MI. However increasing tendency was more significant in mean annual temperature and PE than in mean annual precipitation and MI. Analysis of seasonal climate variation indicates that there showed positive trends in winter and in spring, while the positive trend was more significant in winter than in spring. Furthermore, the relations between climate changes and geographical factors were analyzed, the results show that both climate factors and their interannual variability were correlated to latitude, longitude and altitude, suggesting that latitude is the most climate factor affecting climate changes, followed by altitude and longitude.
2007, 17(4): 325-332.
doi: 10.1007/s11769-007-0325-1
摘要:
Traditionally, the mid-Holocene in most parts of China was thought to be warmer with higher precipitation, resulting from a strong Asian summer monsoon. However, some recent researches have proposed a mid-Holocene drought interval of millennial-scale in East Asian monsoon margin areas. Thus whether mid-Holocene was dry or humid remains an open issue. Here, Zhuyeze palaeolake, the terminal lake of the Shiyang River Drainage lying in Asian monsoon marginal areas, was selected for reconstructing the details of climate variations during the Holocene, especially mid-Holocene, on the basis of a sedimentological analysis. Qingtu Lake (QTL) section of 6.92m depth was taken from Zhuyeze palaeolake. Multi-proxy analysis of QTL section, including grain size, carbonate, TOC, C/N and δ13C of organic matter, was used to document regional climatic changes during 9–3 cal ka B.P. The record shows a major environmental change at 9.0–7.8 cal ka B.P., attributed to a climate trend towards warmth and humidity. This event was followed by a typical regional drought event which occurred during 7.8–7.5 cal ka B.P. And a warm and humid climate prevailed from 7.5 to 5.0 cal ka B.P., attributed to the warm/humid Holocene Optimum in this region. After that, the climate gradually became drier. Moreover, comparison of the climate record from this paper with the summer insolation at 30°N indicates that the climate pattern reflecting the Asian monsoon changes was caused by insolation change.
Traditionally, the mid-Holocene in most parts of China was thought to be warmer with higher precipitation, resulting from a strong Asian summer monsoon. However, some recent researches have proposed a mid-Holocene drought interval of millennial-scale in East Asian monsoon margin areas. Thus whether mid-Holocene was dry or humid remains an open issue. Here, Zhuyeze palaeolake, the terminal lake of the Shiyang River Drainage lying in Asian monsoon marginal areas, was selected for reconstructing the details of climate variations during the Holocene, especially mid-Holocene, on the basis of a sedimentological analysis. Qingtu Lake (QTL) section of 6.92m depth was taken from Zhuyeze palaeolake. Multi-proxy analysis of QTL section, including grain size, carbonate, TOC, C/N and δ13C of organic matter, was used to document regional climatic changes during 9–3 cal ka B.P. The record shows a major environmental change at 9.0–7.8 cal ka B.P., attributed to a climate trend towards warmth and humidity. This event was followed by a typical regional drought event which occurred during 7.8–7.5 cal ka B.P. And a warm and humid climate prevailed from 7.5 to 5.0 cal ka B.P., attributed to the warm/humid Holocene Optimum in this region. After that, the climate gradually became drier. Moreover, comparison of the climate record from this paper with the summer insolation at 30°N indicates that the climate pattern reflecting the Asian monsoon changes was caused by insolation change.
2007, 17(4): 333-340.
doi: 10.1007/s11769-007-0333-1
摘要:
Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the western Jilin Province in 1980–2000 with the help of GIS. The results show that the saline-alkali land rather sharply increased in Da'an during 1995–2000; the main conversion processes in the three counties were from grassland to saline-alkali land and from saline-alkali land to grassland; and the typical shapes, spatial expansion speed and mode, and landscape attributes of the saline-alkali land were different in the three counties, which were closely related to local topography, predominant wind orientation, water resources distribution, etc. The corresponding spatial expansion mode was marginality in Changling, random in Zhenlai and more kernels in Da'an, respectively. Landscape attributes also responded to the spatial-temporal dynamic changes of the saline-alkali land and the landscape indices of Da'an fluctuated greatly. The frame of this research may provide fundamental reference for landscape analysis and give some suggestions for regional sustainable development.
Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the western Jilin Province in 1980–2000 with the help of GIS. The results show that the saline-alkali land rather sharply increased in Da'an during 1995–2000; the main conversion processes in the three counties were from grassland to saline-alkali land and from saline-alkali land to grassland; and the typical shapes, spatial expansion speed and mode, and landscape attributes of the saline-alkali land were different in the three counties, which were closely related to local topography, predominant wind orientation, water resources distribution, etc. The corresponding spatial expansion mode was marginality in Changling, random in Zhenlai and more kernels in Da'an, respectively. Landscape attributes also responded to the spatial-temporal dynamic changes of the saline-alkali land and the landscape indices of Da'an fluctuated greatly. The frame of this research may provide fundamental reference for landscape analysis and give some suggestions for regional sustainable development.
2007, 17(4): 341-348.
doi: 10.1007/s11769-007-0341-1
摘要:
An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality.
An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality.
2007, 17(4): 348-348.
摘要:
The China-France International Symposium on Rural Construction and Development was held in Beijing,China,from 23 to 24 September 2007,under the auspices of National Natural Science Foundation of China(NSFC)and the Institute of Geographic Sciences and Natural Resources Research(IGSNRR),Chinese Academy of Sciences(CAS).The symposium was co-sponsored by the following organizations:IGSNRR,CAS;Specialty Committee of Rural Geography,Geographical Society of France;and Specialty Committee of Sustainable Agriculture & Rural Geography,Geographical Society of China.The local organizers included:Research Center of Regional Agriculture and Rural Development,IGSNRR,CAS;New Countryside Construction and Planning Center of Capital’s Mountainous Region,Beijing Branch of CAS & Beijing Academy of Science and Technology;and the Project Team of“The New Countryside Construction Patterns and Approach to Sustainable Development in Eastern Coastal Region of China”,which is a key project funded by NSFC(No.40635029).Prof.Liu Yansui with his team at IGSNRR organized the symposium.And about 100 scientists attended the symposium,among them some 30 came from outside China(mainly from France).
The China-France International Symposium on Rural Construction and Development was held in Beijing,China,from 23 to 24 September 2007,under the auspices of National Natural Science Foundation of China(NSFC)and the Institute of Geographic Sciences and Natural Resources Research(IGSNRR),Chinese Academy of Sciences(CAS).The symposium was co-sponsored by the following organizations:IGSNRR,CAS;Specialty Committee of Rural Geography,Geographical Society of France;and Specialty Committee of Sustainable Agriculture & Rural Geography,Geographical Society of China.The local organizers included:Research Center of Regional Agriculture and Rural Development,IGSNRR,CAS;New Countryside Construction and Planning Center of Capital’s Mountainous Region,Beijing Branch of CAS & Beijing Academy of Science and Technology;and the Project Team of“The New Countryside Construction Patterns and Approach to Sustainable Development in Eastern Coastal Region of China”,which is a key project funded by NSFC(No.40635029).Prof.Liu Yansui with his team at IGSNRR organized the symposium.And about 100 scientists attended the symposium,among them some 30 came from outside China(mainly from France).
2007, 17(4): 349-356.
doi: 10.1007/s11769-007-0349-6
摘要:
Land use/cover change (LUCC) is one of the main boundary conditions which influence many hydrologic processes. In view of the importance of Taihu Lake Watershed in China and the urgency of discovering the impacts of LUCC on storm runoff, two flood events under five land cover scenarios in the Xitiaoxi River Basin of the upstream of Taihu Lake watershed were simulated by distributed hydrologic modeling system HEC-HMS. The influences of each land cover on storm runoff were discussed. It was concluded that under the same rainstorm the ascending order of runoff coefficient and peak flow produced by the 5 different land covers were woodland, shrub, grassland, arable land, and built-up land; the descending order of swelling time were woodland, shrub, grassland, arable land, and built-up land. Scenario of built-up land was the first to reach peak flow, then arable land, grassland, shrub, and woodland. There were close relationships between the runoff coefficients produced by the 5 different land covers. The degrees of impacts on runoff coefficient of land cover change modes were sorted by descending: woodland to built-up land, shrub to built-up land, grassland to built-up land, arable land to built-up land, woodland to arable land, shrub to arable land, arable land to grassland, shrub to grassland, grassland to arable land, and woodland to shrub. Urbanization will contribute to flood disaster, while forestation will mitigate flood disaster.
Land use/cover change (LUCC) is one of the main boundary conditions which influence many hydrologic processes. In view of the importance of Taihu Lake Watershed in China and the urgency of discovering the impacts of LUCC on storm runoff, two flood events under five land cover scenarios in the Xitiaoxi River Basin of the upstream of Taihu Lake watershed were simulated by distributed hydrologic modeling system HEC-HMS. The influences of each land cover on storm runoff were discussed. It was concluded that under the same rainstorm the ascending order of runoff coefficient and peak flow produced by the 5 different land covers were woodland, shrub, grassland, arable land, and built-up land; the descending order of swelling time were woodland, shrub, grassland, arable land, and built-up land. Scenario of built-up land was the first to reach peak flow, then arable land, grassland, shrub, and woodland. There were close relationships between the runoff coefficients produced by the 5 different land covers. The degrees of impacts on runoff coefficient of land cover change modes were sorted by descending: woodland to built-up land, shrub to built-up land, grassland to built-up land, arable land to built-up land, woodland to arable land, shrub to arable land, arable land to grassland, shrub to grassland, grassland to arable land, and woodland to shrub. Urbanization will contribute to flood disaster, while forestation will mitigate flood disaster.
2007, 17(4): 357-363.
doi: 10.1007/s11769-007-0363-6
摘要:
Normalized difference vegetation index (NDVI) data, obtained from remote sensing information, are essential in the Shuttleworth-Wallace (S-W) model for estimation of evapotranspiration. In order to study the effect of temporal resolution of NDVI on potential evapotranspiration (PET) estimation and hydrological model performance, monthly and 10-day NDVI data set were used to estimate potential evapotranspiration from January 1985 to December 1987 in Huangnizhuang catchment, Anhui Province, China. The differences of the two calculation results were analyzed and used to drive the block-wise use of the TOPMODEL with the Muskingum–Cunge routing (BTOPMC) model to test the effect on model performance. The results show that both annual and monthly PETs estimated by 10-day NDVI are lower than those estimated by monthly NDVI. Annual PET from the vegetation root zone (PETr) lowers 9.77%–13.64% and monthly PETr lowers 3.28%–17.44% in the whole basin. PET from the vegetation interception (PETi) shows the same trend as PETr. In addition, temporal resolution of NDVI has more effect on PETr in summer and on PETi in winter. The correlation between PETr as estimated by 10-day NDVI and pan measurement (R2= 0.835) is better than that between monthly NDVI and pan measurement (R2 = 0.775). The two potential evapotranspiration estimates were used to drive the BTOPMC model and calibrate parameters, and model performance was found to be similar. In summary, the effect of temporal resolution of NDVI on potential evapotranspiration estimation is significant, but trivial on hydrological model performance.
Normalized difference vegetation index (NDVI) data, obtained from remote sensing information, are essential in the Shuttleworth-Wallace (S-W) model for estimation of evapotranspiration. In order to study the effect of temporal resolution of NDVI on potential evapotranspiration (PET) estimation and hydrological model performance, monthly and 10-day NDVI data set were used to estimate potential evapotranspiration from January 1985 to December 1987 in Huangnizhuang catchment, Anhui Province, China. The differences of the two calculation results were analyzed and used to drive the block-wise use of the TOPMODEL with the Muskingum–Cunge routing (BTOPMC) model to test the effect on model performance. The results show that both annual and monthly PETs estimated by 10-day NDVI are lower than those estimated by monthly NDVI. Annual PET from the vegetation root zone (PETr) lowers 9.77%–13.64% and monthly PETr lowers 3.28%–17.44% in the whole basin. PET from the vegetation interception (PETi) shows the same trend as PETr. In addition, temporal resolution of NDVI has more effect on PETr in summer and on PETi in winter. The correlation between PETr as estimated by 10-day NDVI and pan measurement (R2= 0.835) is better than that between monthly NDVI and pan measurement (R2 = 0.775). The two potential evapotranspiration estimates were used to drive the BTOPMC model and calibrate parameters, and model performance was found to be similar. In summary, the effect of temporal resolution of NDVI on potential evapotranspiration estimation is significant, but trivial on hydrological model performance.
2007, 17(4): 364-369.
doi: 10.1007/s11769-007-0364-7
摘要:
The visible and infrared bands of Landsat Thematic Mapper (TM) can be used for inland water studies. A method of retrieving water-leaving radiance from TM image over Taihu Lake in Jiangsu Province of China was investigated in this article. To estimate water-leaving radiance, atmospheric correction was performed in three visible bands of 485nm, 560nm and 660nm. Rayleigh scattering was computed precisely, and the aerosol contribution was estimated by adopting the clear-water-pixels approach. The clear waters were identified by using the Landsat TM middle-infrared band (2.1μm), and the water-leaving radiance of clear water pixels in the green band was estimated by using field data. Aerosol scattering at green band was derived for six points, and interpolated to match the TM image. Assuming the atmospheric correction coefficient was 1.0, the aerosol scattering image at blue and red bands were derived. Based on a simplified atmospheric radiation transfer model, the water-leaving radiance for three visible bands was retrieved. The water-leaving radiance was normalized to make it comparable with that estimated from other remotely sensed data acquired at different times, and under different atmospheric conditions. Additionally, remotely sensed reflectance of water was computed. To evaluate the atmospheric correction method presented in this article, the correlation was analyzed between the corrected remotely sensed data and the measured water parameters based on the retrieval model. The results show that the atmospheric correction method based on the image itself is more effective for the retrieval of water parameters from Landsat TM data than 6S (Second Simulation of the Satellite Signal in the Solar Spectrum) code based on standard atmospheric and aerosol models.
The visible and infrared bands of Landsat Thematic Mapper (TM) can be used for inland water studies. A method of retrieving water-leaving radiance from TM image over Taihu Lake in Jiangsu Province of China was investigated in this article. To estimate water-leaving radiance, atmospheric correction was performed in three visible bands of 485nm, 560nm and 660nm. Rayleigh scattering was computed precisely, and the aerosol contribution was estimated by adopting the clear-water-pixels approach. The clear waters were identified by using the Landsat TM middle-infrared band (2.1μm), and the water-leaving radiance of clear water pixels in the green band was estimated by using field data. Aerosol scattering at green band was derived for six points, and interpolated to match the TM image. Assuming the atmospheric correction coefficient was 1.0, the aerosol scattering image at blue and red bands were derived. Based on a simplified atmospheric radiation transfer model, the water-leaving radiance for three visible bands was retrieved. The water-leaving radiance was normalized to make it comparable with that estimated from other remotely sensed data acquired at different times, and under different atmospheric conditions. Additionally, remotely sensed reflectance of water was computed. To evaluate the atmospheric correction method presented in this article, the correlation was analyzed between the corrected remotely sensed data and the measured water parameters based on the retrieval model. The results show that the atmospheric correction method based on the image itself is more effective for the retrieval of water parameters from Landsat TM data than 6S (Second Simulation of the Satellite Signal in the Solar Spectrum) code based on standard atmospheric and aerosol models.
2007, 17(4): 370-375.
doi: 10.1007/s11769-007-0370-9
摘要:
In order to approach the characteristics of nitrogen and phosphorus pollution caused by cage culture and the balance of nitrogen and phosphorus during the process of cage culture, a monitoring was conducted in Daya Bay of Guangdong Province, China from April 2002 to Jane 2003. The results show that the concentrations of total nitrogen (TN) in the waters at the sites with five and ten years of cage culture history are 1.8 and 2.3 times of that at control site respectively. Ammonium (NH3-N) is the main form of nitrogen in spring while nitrate (NO3-) in winter. The concentrations of TN, total dissolved nitrogen (TDN) and dissolved organic nitrogen (DON) are highest in autumn. The concentration of phosphorus increases with the increasing of the culturing time, among which phosphate (PO43-) increases most obviously. The concentrations of total phosphorus (TP) and total dissolved phosphorus (TDP) are highest in autumn. The nitrogen and phosphorus are accumulated significantly in the sediment of cage culture area. The model of N balance in the cage culture area: bait (70.62%) + fry (0.28%) + input by tide (14.8%) + release from sediment (14.3%) = harvest of adult fish (12.07%) + deposition into sediment (28.75%) + output by tide (56.18%) + others (3.00%). The model of P balance: bait (83.11%) + fry (0.17%) + input by tide (12.23%) + release from sediment (4.49%) = harvest of adult fish (8.43%) + deposition into sediment (48.59%) + output by tide (41.94%) + others (1.04%). In one fish growth year, the contents of nitrogen and phosphorus in harvest of adult fish are only 17.0% and 10.1% of the contents of nitrogen and phosphorus in fish bait and fry, wherein 83% of nitrogen and more than 89% of phosphorus in fish bait became marine pollutants.
In order to approach the characteristics of nitrogen and phosphorus pollution caused by cage culture and the balance of nitrogen and phosphorus during the process of cage culture, a monitoring was conducted in Daya Bay of Guangdong Province, China from April 2002 to Jane 2003. The results show that the concentrations of total nitrogen (TN) in the waters at the sites with five and ten years of cage culture history are 1.8 and 2.3 times of that at control site respectively. Ammonium (NH3-N) is the main form of nitrogen in spring while nitrate (NO3-) in winter. The concentrations of TN, total dissolved nitrogen (TDN) and dissolved organic nitrogen (DON) are highest in autumn. The concentration of phosphorus increases with the increasing of the culturing time, among which phosphate (PO43-) increases most obviously. The concentrations of total phosphorus (TP) and total dissolved phosphorus (TDP) are highest in autumn. The nitrogen and phosphorus are accumulated significantly in the sediment of cage culture area. The model of N balance in the cage culture area: bait (70.62%) + fry (0.28%) + input by tide (14.8%) + release from sediment (14.3%) = harvest of adult fish (12.07%) + deposition into sediment (28.75%) + output by tide (56.18%) + others (3.00%). The model of P balance: bait (83.11%) + fry (0.17%) + input by tide (12.23%) + release from sediment (4.49%) = harvest of adult fish (8.43%) + deposition into sediment (48.59%) + output by tide (41.94%) + others (1.04%). In one fish growth year, the contents of nitrogen and phosphorus in harvest of adult fish are only 17.0% and 10.1% of the contents of nitrogen and phosphorus in fish bait and fry, wherein 83% of nitrogen and more than 89% of phosphorus in fish bait became marine pollutants.
2007, 17(4): 376-382.
doi: 10.1007/s11769-007-0376-3
摘要:
The distribution of Al and F contents and the relationship between Al and F in tea plants and soils of 12 tea gardens in Central and Southwest China were investigated from October 31 to November 14, 2006. The results show that there were differences in pH, CEC, the contents of organic matter (OM), Al and F in the different soils of the tea gardens. The Al content ranged from 1196 to 7976mg/kg for old leaf, 370 to 2681mg/kg for young leaf and 285 to 525mg/kg for stem, whereas the content of F ranged from 221 to 1504mg/kg for old leaf, 49 to 602mg/kg for young leaf and 13.5 to 77.5mg/kg for stem. The concentrations of labile Al varied obviously in the different soils, but the distribution law of labile Al content for the same garden was Alexchangeable≈AlFe-Mn oxide>Alorganic>Alwater-soluble. The contents of different labile F fractions varied slightly in the different soils and the different soil layers, though the exchangeable F content was lowest among the labile F in the soils. The concentrations of Al and F in tea plants increased with increasing amount of water-soluble Al or F, especially the amount of water-soluble fractions in the soil layer of 0–20cm.The correlation between Al content and F content in the tea leaf was more significant than that in the tea stem. Furthermore, the correlation between Al content and F content in whole tea plant was strongly significant (r=0.8763, p<0.01, n=36). There were evident tendency that Al concentration increased with the increase of F concentration in different soil layers. The correlation of water-soluble Al with water-soluble F in all soils was also strongly significant (r=0.7029, p<0.01, n=34). The results may provide a proof that Al and F are jointly taken up by tea plants to some extent in natural tea gardens.
The distribution of Al and F contents and the relationship between Al and F in tea plants and soils of 12 tea gardens in Central and Southwest China were investigated from October 31 to November 14, 2006. The results show that there were differences in pH, CEC, the contents of organic matter (OM), Al and F in the different soils of the tea gardens. The Al content ranged from 1196 to 7976mg/kg for old leaf, 370 to 2681mg/kg for young leaf and 285 to 525mg/kg for stem, whereas the content of F ranged from 221 to 1504mg/kg for old leaf, 49 to 602mg/kg for young leaf and 13.5 to 77.5mg/kg for stem. The concentrations of labile Al varied obviously in the different soils, but the distribution law of labile Al content for the same garden was Alexchangeable≈AlFe-Mn oxide>Alorganic>Alwater-soluble. The contents of different labile F fractions varied slightly in the different soils and the different soil layers, though the exchangeable F content was lowest among the labile F in the soils. The concentrations of Al and F in tea plants increased with increasing amount of water-soluble Al or F, especially the amount of water-soluble fractions in the soil layer of 0–20cm.The correlation between Al content and F content in the tea leaf was more significant than that in the tea stem. Furthermore, the correlation between Al content and F content in whole tea plant was strongly significant (r=0.8763, p<0.01, n=36). There were evident tendency that Al concentration increased with the increase of F concentration in different soil layers. The correlation of water-soluble Al with water-soluble F in all soils was also strongly significant (r=0.7029, p<0.01, n=34). The results may provide a proof that Al and F are jointly taken up by tea plants to some extent in natural tea gardens.
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