A computerized parametric methodology was applied to monitor, map, and estimate vegetation change in combination with '3S' (RS-remote sensing, GIS-geographic information systems, and GPS-global positioning sys...A computerized parametric methodology was applied to monitor, map, and estimate vegetation change in combination with '3S' (RS-remote sensing, GIS-geographic information systems, and GPS-global positioning system) technology and change detection techniques at a 1:50000 mapping scale in the Letianxi Watershed of western Hubei Province, China. Satellite images (Landsat TM 1997 and Landsat ETM 2002) and thematic maps were used to provide comprehensive views of surface conditions such as vegetation cover and land use change. With ER Mapper and ERDAS software, the normalized difference vegetation index (NDVI) was computed and then classified into six vegetation density classes. ARC/INFO and ArcView software were used along with field observation data by GPS for analysis. Results obtained using spatial analysis methods showed that NDVI was a valuable first cut indicator for vegetation and land use systems. A regression analysis revealed that NDVI explained 94.5% of the variations for vegetation cover in the largest vegetation area, indicating that the relationship between vegetation and NDVI was not a simple linear process. Vegetation cover increased in four of areas. This meant 60.9% of land area had very slight to slight vegetation change, while 39.1% had moderate to severe vegetation change. Thus, the study area, in general, was exposed to a high risk of vegetation cover change.展开更多
Cloud computing has emerged as a leading computing paradigm,with an increasing number of geographic information(geo-information) processing tasks now running on clouds.For this reason,geographic information system/rem...Cloud computing has emerged as a leading computing paradigm,with an increasing number of geographic information(geo-information) processing tasks now running on clouds.For this reason,geographic information system/remote sensing(GIS/RS) researchers rent more public clouds or establish more private clouds.However,a large proportion of these clouds are found to be underutilized,since users do not deal with big data every day.The low usage of cloud resources violates the original intention of cloud computing,which is to save resources by improving usage.In this work,a low-cost cloud computing solution was proposed for geo-information processing,especially for temporary processing tasks.The proposed solution adopted a hosted architecture and can be realized based on ordinary computers in a common GIS/RS laboratory.The usefulness and effectiveness of the proposed solution was demonstrated by using big data simplification as a case study.Compared to commercial public clouds and dedicated private clouds,the proposed solution is more low-cost and resource-saving,and is more suitable for GIS/RS applications.展开更多
This study applied a computerized parametric methodology to monitor, map, and quantify land degradation by salinization risk detection techniques at a 1:250 000 mapping scale using geo-information technology. The nor...This study applied a computerized parametric methodology to monitor, map, and quantify land degradation by salinization risk detection techniques at a 1:250 000 mapping scale using geo-information technology. The northern part of the Shaanxi province in China was taken as a case. Multi-temporal remotely sensed materials of both Landsat TM and thematic maps (ETM+) were used as the bases to provide comprehensive views of surface conditions such as vegetation cover and salinization detection. With ERDAS ver. 9.1 software, the Normalized Differential Salinity Index (NDSl) and Salinity Index (S.I.) were computed and then evaluated for land degradation by salinization. Arc/Info ver. 9.2 software was used along with field observation data (GPS) for analysis. Using spatial analysis methods, results showed that 19 973.1 km^2 (72%) of land had no risk of land degradation by salinization, 3 684.7 km^2 (13%) had slight land degradation by salinization risk, 2 797.9 km^2 (10%) had moderate land degradation by salinization risk, and 1 218.9 km^2 (4%) of the total land area was at a high risk of land degradation by salinization. The study area, in general, is exposed to a high risk of soil salinization.展开更多
The three-period (1995, 1998 and 2003) remote sensing images in Jinan City, China are selected. And the information of green land, construction land, woodland and water body is extracted by using the image processing ...The three-period (1995, 1998 and 2003) remote sensing images in Jinan City, China are selected. And the information of green land, construction land, woodland and water body is extracted by using the image processing module of remote-sensing software and computerized interpretation module. Both the change table and transfer matrix table of land use area are analyzed by modeling module of remote-sensing software. Then, the Geo-information Tupu is obtained; and the temporal and spatial variation of land use in Jinan City is monitored and analyzed by Geo-information Tupu and transfer matrix. Result shows that land use structure change of Jinan City in the years 1995-1998 shows a transformation from green land to construction land. Area of green land circulating into construction land reaches 62.27 square kilometers, accounting for 25.84% of the initial green land. In the year 1998, areas of woodland and green land are reduced due to the urban expansion of Jinan City. However, with the enhancement of people's awareness of environmental protection, areas of woodland and green land gradually increase in the year 2003, which are still less than those in the year 1995.展开更多
Along with the development of Internet, geo-information sharing and Open GIS are of increasing importance for GIS application fields. Southwestern China consists of several provinces or districts, they are Sichuan, Gu...Along with the development of Internet, geo-information sharing and Open GIS are of increasing importance for GIS application fields. Southwestern China consists of several provinces or districts, they are Sichuan, Guizhou, Yunnan, Chongqing, etc. The economic and information cooperation among them are of significance. The pilot platform for resource and environment geo-information sharing for the southwestern China based on Web services, OGC(Open GIS Consortium) WFS(Web feature service) is constructed. Via this pilot platform, a loose information sharing mode can be implemented to improve their cooperation level.展开更多
Along with the forthcoming of Google Earth, Virtual Earth, the next generation of Internet, Web 2.0, grid computing and smart sensor web, comes the new era for geo-information. In this paper, main features of new geo-...Along with the forthcoming of Google Earth, Virtual Earth, the next generation of Internet, Web 2.0, grid computing and smart sensor web, comes the new era for geo-information. In this paper, main features of new geo-information era are discussed. This new era is characterized by these features: serviced users are extended from professionals to all public users, the users are data and information providers as well, geospatial data provided are no longer measurement-by-specification but measurement-on- demand through smart sensor web, and services are transferred from being data-driven to application- driven. Such problems as out-of-order issues in geographic data collection and information prolifer- ation, quality issues in geographic information updating, security issues in geographic information services, privacy issues in sharing geographic information and property issues in sharing geographic information, which are brought about by new geo-information era, especially those confronted in geo- information science and geo-spatial information industry, are analyzed. Then strategies concerning standards, planning, laws, technology and applications are proposed.展开更多
Over the last 20 years,Africa has witnessed a slow but steady advancement in space-based technologies as they are increasingly recognized as an essential tool for decision-making that can leapfrog African development....Over the last 20 years,Africa has witnessed a slow but steady advancement in space-based technologies as they are increasingly recognized as an essential tool for decision-making that can leapfrog African development.A critical review on the outcome of a survey questionnaire focused on African private sector industries and universities,services and education/training in EO and Geo-Information Sciences,combined with literature review,and personal contacts reveal optimism for success in four sectors.These include the public sector(Government ministries and departments);Academic institutions(universities/colleges/national or regional centers);and space agencies and private sector companies.These sectors are intertwined and fundamental for creating an enabling environment for solutions to a broad spectrum of pressing priorities:job creation,poverty alleviation,and sustainable resource management.The result shows that there is an uptake in the number of institutions and market segments created.To date,there are more than 90 academic institutions and over 53 national space agencies in 28 countries.Within the 53 national space agencies,11 African countries have already launched a total of 36 satellites into orbit,and additional five are expected by the first quarter of 2021;another five by 2025;thus,amounting to 46 satellites not foreseen ten years ago.In addition,there are now ten receiving and tracking stations in six African countries and 17 scientific National Associations or Societies with specialized expertise in Geo-Information technologies.The updated survey on the private sector in 2019 ascertained that around 4110 people are working in 130 of the 229 EO and Geo-Information Science companies identified in Africa.Ongoing investigations reiterate that companies dealing with space-based datasets and Geo-Information Sciences together with the private spin-off companies today absorb more than 15,000 people and the assumption is that this number is going to exceed 100,000 by the year 2025.展开更多
Comprehensive study on land-use change of spatial pattern and temporal process is the key component in LUCC study nowadays. Based on the theories and methods of Geo-information Tupu (Carto-methodology in Geo-informati...Comprehensive study on land-use change of spatial pattern and temporal process is the key component in LUCC study nowadays. Based on the theories and methods of Geo-information Tupu (Carto-methodology in Geo-information, CMGI), integration of spatial pattern and temporal processes of land-use change in the Yellow River Delta (YRD) are studied in the paper, which is supported by ERDAS and ARC/INFO software. The main contents include: (1) concept models of Tupu by spatial-temporal integration on land-use change, whose Tupu unit is synthesized by "Spatial·Attribute·Process" features and composed of relatively homogeneous geographical unit and temporal unit; (2) data sources and handling process, where four stages of spatial features in 1956, 1984, 1991, and 1996 are acquired; (3) integration of series of temporal-spatial Tupu, reconstruction series of "Arising" Tupu, spatial-temporal Process Tupu and the spatial temporal Pattern Tupu on land-use change by remap tables; (4) Pattern Tupu analysis on land-use change in YRD during 1956-1996; and (5) spatial difference of the Pattern Tupu analysis by dynamic Tupu units. The various landform units and seven sub-deltas generated by the Yellow River since 1855 are different. The Tupu analysis on land-use in the paper is a promising try on the comprehensive research of "spatial pattern of dynamic process" and "temporal process of spatial pattern" in LUCC research. The Tupu methodology would be a powerful and efficient tool on integrated studies of spatial pattern and temporal process in Geo-science.展开更多
Gave a brief introduction to the origin,concepted and hierarchical structure of Digital Mine.As a huge complex system,Digital Mine took data base and model base to- gether as a mine data management system being its co...Gave a brief introduction to the origin,concepted and hierarchical structure of Digital Mine.As a huge complex system,Digital Mine took data base and model base to- gether as a mine data management system being its core,and Digital Mine was com- prised of five subsystems including data obtaining system,integral dispatching system, applied engineering system,data processing system,and data management system.Be- ing a digitally 3D visualized representation and a spatial information infrastructure of an actual mine,Digital Mine had three basic features such as data warehouse,information reference and digital platform.The present developments of Digital Mine in mining industry, research and education were also introduced.Examples were shown for present Digital Mine construction in China.The development trends,the key technologies and the recent construction procedures on Digital Mine were presented.展开更多
The East African Community is a regional block that brings together Kenya, Uganda, Tanzania, Rwanda, Burundi and South Sudan into various forms of economic partnership, the eventual dream being to achieve political fe...The East African Community is a regional block that brings together Kenya, Uganda, Tanzania, Rwanda, Burundi and South Sudan into various forms of economic partnership, the eventual dream being to achieve political federation. The current activities within this community, plus the block’s further development, require the generation and sharing of much geo-information to support the attendant decision-making. Such geo-information can be best served through a harmonized cartographic service with common standards. Such a harmonized service is not only lacking, but even the status of the current national services is also largely unknown. This paper reports on a study undertaken to establish this status, as represented by twelve elements of a cartographic service that the authors are able to establish. Results of the study have shown that the present national services are characterized by inadequate basic datasets that remain largely analogue. In addition, there are non-uniform spatial reference systems, inadequate cartographic human resources and lack of common mapping standards;further, funding for mapping activities remains low in national budgets. Given that over 80% of decisions are influenced by geo-spatial data, these findings point to an urgent need to improve, harmonize and digitize these services as the way forward, if the East African Community is to remain globally competitive.展开更多
In this paper, Land at 8 OLI image data from 2013 to 2017 was interpreted by visual interpretation combined with supervised classification to extract the information of land use distribution in the Yellow River Delta ...In this paper, Land at 8 OLI image data from 2013 to 2017 was interpreted by visual interpretation combined with supervised classification to extract the information of land use distribution in the Yellow River Delta in China. The characteristics of Land Use Cover Change (LUCC) in the past five years which were analyzed by land use spatial analysis method based on buffer zone were discussed to obtain the land use index trend of five land types in buffer zones at different distance. The land use transfer maps of 2013 and 2017 were made by using the geo-information mapping method. The spatial-temporal change rules and the development process of land use in the Yellow River Delta during the past five years were analyzed. According to the analysis results, the comprehensive index of land use degree in the study area was in the middle level. The land use transfer maps were mainly consisted of farmland and grassland. The change rate of bare land to vegetation was 20.21% and that of vegetation to bare land was 14.15%. This study can provide effective basis for the scientific management of land and rational guidance for planning in this area.展开更多
Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process ...Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process in landscape ecology, the methodology of landscape information Tupu in studying the swing process of the Yellow River (YR) over the Yellow River Delta (YRD) during 1855― 2000 has been demonstrated. The main content includes: (1) methodology of landscape information Tupu; (2) evolution process Tupu of YR rump channels; (3) evolution process Tupu of the 7 pieces of subdeltas in YRD during 1855―2000; (4) landscape information Tupu of the modern YRD and the current YRD; (5) landscape information Tupu of YR rump channels on the 7 pieces of subdeltas during 1855―2000; and (6) corridor-matrix landscape information Tupu by YR swings. The methodology of landscape information Tupu here is still primary but we hope that it could provide a new tool for exploring an integrated research on spatiotemporal approaches for landscape "pattern and process".展开更多
A model integrating geo-information and self-organizing map(SOM) for exploring the database of soil environmental surveys was established. The dataset of 5 heavy metals(As, Cd, Cr, Hg, and Pb) was built by the regular...A model integrating geo-information and self-organizing map(SOM) for exploring the database of soil environmental surveys was established. The dataset of 5 heavy metals(As, Cd, Cr, Hg, and Pb) was built by the regular grid sampling in Hechi, Guangxi Zhuang Autonomous Region in southern China. Auxiliary datasets were collected throughout the study area to help interpret the potential causes of pollution. The main findings are as follows:(1) Soil samples of 5 elements exhibited strong variation and high skewness. High pollution risk existed in the case study area, especially Hg and Cd.(2) As and Pb had a similar topological distribution pattern, meaning they behaved similarly in the soil environment. Cr had behaviours in soil different from those of the other 4 elements.(3) From the U-matrix of SOM networks, 3 levels of SEQ were identified, and 11 high risk areas of soil heavy metal-contaminated were found throughout the study area, which were basically near rivers,factories, and ore zones.(4) The variations of contamination index(CI) followed the trend of construction land(1.353)> forestland(1.267)> cropland(1.175)> grassland(1.056), which suggest that decision makers should focus more on the problem of soil pollution surrounding industrial and mining enterprises and farmland.展开更多
基金Project Supported by the National Natural Science Foundation of China (No. 40271073).
文摘A computerized parametric methodology was applied to monitor, map, and estimate vegetation change in combination with '3S' (RS-remote sensing, GIS-geographic information systems, and GPS-global positioning system) technology and change detection techniques at a 1:50000 mapping scale in the Letianxi Watershed of western Hubei Province, China. Satellite images (Landsat TM 1997 and Landsat ETM 2002) and thematic maps were used to provide comprehensive views of surface conditions such as vegetation cover and land use change. With ER Mapper and ERDAS software, the normalized difference vegetation index (NDVI) was computed and then classified into six vegetation density classes. ARC/INFO and ArcView software were used along with field observation data by GPS for analysis. Results obtained using spatial analysis methods showed that NDVI was a valuable first cut indicator for vegetation and land use systems. A regression analysis revealed that NDVI explained 94.5% of the variations for vegetation cover in the largest vegetation area, indicating that the relationship between vegetation and NDVI was not a simple linear process. Vegetation cover increased in four of areas. This meant 60.9% of land area had very slight to slight vegetation change, while 39.1% had moderate to severe vegetation change. Thus, the study area, in general, was exposed to a high risk of vegetation cover change.
基金Project(41401434)supported by the National Natural Science Foundation of China
文摘Cloud computing has emerged as a leading computing paradigm,with an increasing number of geographic information(geo-information) processing tasks now running on clouds.For this reason,geographic information system/remote sensing(GIS/RS) researchers rent more public clouds or establish more private clouds.However,a large proportion of these clouds are found to be underutilized,since users do not deal with big data every day.The low usage of cloud resources violates the original intention of cloud computing,which is to save resources by improving usage.In this work,a low-cost cloud computing solution was proposed for geo-information processing,especially for temporary processing tasks.The proposed solution adopted a hosted architecture and can be realized based on ordinary computers in a common GIS/RS laboratory.The usefulness and effectiveness of the proposed solution was demonstrated by using big data simplification as a case study.Compared to commercial public clouds and dedicated private clouds,the proposed solution is more low-cost and resource-saving,and is more suitable for GIS/RS applications.
基金the Geo-information Science and Technology Program (No. IRT 0438)
文摘This study applied a computerized parametric methodology to monitor, map, and quantify land degradation by salinization risk detection techniques at a 1:250 000 mapping scale using geo-information technology. The northern part of the Shaanxi province in China was taken as a case. Multi-temporal remotely sensed materials of both Landsat TM and thematic maps (ETM+) were used as the bases to provide comprehensive views of surface conditions such as vegetation cover and salinization detection. With ERDAS ver. 9.1 software, the Normalized Differential Salinity Index (NDSl) and Salinity Index (S.I.) were computed and then evaluated for land degradation by salinization. Arc/Info ver. 9.2 software was used along with field observation data (GPS) for analysis. Using spatial analysis methods, results showed that 19 973.1 km^2 (72%) of land had no risk of land degradation by salinization, 3 684.7 km^2 (13%) had slight land degradation by salinization risk, 2 797.9 km^2 (10%) had moderate land degradation by salinization risk, and 1 218.9 km^2 (4%) of the total land area was at a high risk of land degradation by salinization. The study area, in general, is exposed to a high risk of soil salinization.
基金Supported by the Natural Science Foundation of Shandong Province(Y2007E21)the Key Programs for Science and Technology Development of Shandong Province(2006GG2308005)the Soft Science Project of the Shandong Provincial Department of Science and Technology (200624-14)
文摘The three-period (1995, 1998 and 2003) remote sensing images in Jinan City, China are selected. And the information of green land, construction land, woodland and water body is extracted by using the image processing module of remote-sensing software and computerized interpretation module. Both the change table and transfer matrix table of land use area are analyzed by modeling module of remote-sensing software. Then, the Geo-information Tupu is obtained; and the temporal and spatial variation of land use in Jinan City is monitored and analyzed by Geo-information Tupu and transfer matrix. Result shows that land use structure change of Jinan City in the years 1995-1998 shows a transformation from green land to construction land. Area of green land circulating into construction land reaches 62.27 square kilometers, accounting for 25.84% of the initial green land. In the year 1998, areas of woodland and green land are reduced due to the urban expansion of Jinan City. However, with the enhancement of people's awareness of environmental protection, areas of woodland and green land gradually increase in the year 2003, which are still less than those in the year 1995.
基金Supported by the International Cooperation Project of Ministry of Science and Technology of China (No.2004DF1003589) .
文摘Along with the development of Internet, geo-information sharing and Open GIS are of increasing importance for GIS application fields. Southwestern China consists of several provinces or districts, they are Sichuan, Guizhou, Yunnan, Chongqing, etc. The economic and information cooperation among them are of significance. The pilot platform for resource and environment geo-information sharing for the southwestern China based on Web services, OGC(Open GIS Consortium) WFS(Web feature service) is constructed. Via this pilot platform, a loose information sharing mode can be implemented to improve their cooperation level.
基金Supported by the National Basic Research Program of China (Grant No. 2004CB318206)
文摘Along with the forthcoming of Google Earth, Virtual Earth, the next generation of Internet, Web 2.0, grid computing and smart sensor web, comes the new era for geo-information. In this paper, main features of new geo-information era are discussed. This new era is characterized by these features: serviced users are extended from professionals to all public users, the users are data and information providers as well, geospatial data provided are no longer measurement-by-specification but measurement-on- demand through smart sensor web, and services are transferred from being data-driven to application- driven. Such problems as out-of-order issues in geographic data collection and information prolifer- ation, quality issues in geographic information updating, security issues in geographic information services, privacy issues in sharing geographic information and property issues in sharing geographic information, which are brought about by new geo-information era, especially those confronted in geo- information science and geo-spatial information industry, are analyzed. Then strategies concerning standards, planning, laws, technology and applications are proposed.
文摘Over the last 20 years,Africa has witnessed a slow but steady advancement in space-based technologies as they are increasingly recognized as an essential tool for decision-making that can leapfrog African development.A critical review on the outcome of a survey questionnaire focused on African private sector industries and universities,services and education/training in EO and Geo-Information Sciences,combined with literature review,and personal contacts reveal optimism for success in four sectors.These include the public sector(Government ministries and departments);Academic institutions(universities/colleges/national or regional centers);and space agencies and private sector companies.These sectors are intertwined and fundamental for creating an enabling environment for solutions to a broad spectrum of pressing priorities:job creation,poverty alleviation,and sustainable resource management.The result shows that there is an uptake in the number of institutions and market segments created.To date,there are more than 90 academic institutions and over 53 national space agencies in 28 countries.Within the 53 national space agencies,11 African countries have already launched a total of 36 satellites into orbit,and additional five are expected by the first quarter of 2021;another five by 2025;thus,amounting to 46 satellites not foreseen ten years ago.In addition,there are now ten receiving and tracking stations in six African countries and 17 scientific National Associations or Societies with specialized expertise in Geo-Information technologies.The updated survey on the private sector in 2019 ascertained that around 4110 people are working in 130 of the 229 EO and Geo-Information Science companies identified in Africa.Ongoing investigations reiterate that companies dealing with space-based datasets and Geo-Information Sciences together with the private spin-off companies today absorb more than 15,000 people and the assumption is that this number is going to exceed 100,000 by the year 2025.
文摘Comprehensive study on land-use change of spatial pattern and temporal process is the key component in LUCC study nowadays. Based on the theories and methods of Geo-information Tupu (Carto-methodology in Geo-information, CMGI), integration of spatial pattern and temporal processes of land-use change in the Yellow River Delta (YRD) are studied in the paper, which is supported by ERDAS and ARC/INFO software. The main contents include: (1) concept models of Tupu by spatial-temporal integration on land-use change, whose Tupu unit is synthesized by "Spatial·Attribute·Process" features and composed of relatively homogeneous geographical unit and temporal unit; (2) data sources and handling process, where four stages of spatial features in 1956, 1984, 1991, and 1996 are acquired; (3) integration of series of temporal-spatial Tupu, reconstruction series of "Arising" Tupu, spatial-temporal Process Tupu and the spatial temporal Pattern Tupu on land-use change by remap tables; (4) Pattern Tupu analysis on land-use change in YRD during 1956-1996; and (5) spatial difference of the Pattern Tupu analysis by dynamic Tupu units. The various landform units and seven sub-deltas generated by the Yellow River since 1855 are different. The Tupu analysis on land-use in the paper is a promising try on the comprehensive research of "spatial pattern of dynamic process" and "temporal process of spatial pattern" in LUCC research. The Tupu methodology would be a powerful and efficient tool on integrated studies of spatial pattern and temporal process in Geo-science.
基金the National 863 High-Tech.Program of China(2006AA12Z2162007AA06Z108)the Natural Science Funds of China(50525414,40571137)
文摘Gave a brief introduction to the origin,concepted and hierarchical structure of Digital Mine.As a huge complex system,Digital Mine took data base and model base to- gether as a mine data management system being its core,and Digital Mine was com- prised of five subsystems including data obtaining system,integral dispatching system, applied engineering system,data processing system,and data management system.Be- ing a digitally 3D visualized representation and a spatial information infrastructure of an actual mine,Digital Mine had three basic features such as data warehouse,information reference and digital platform.The present developments of Digital Mine in mining industry, research and education were also introduced.Examples were shown for present Digital Mine construction in China.The development trends,the key technologies and the recent construction procedures on Digital Mine were presented.
文摘The East African Community is a regional block that brings together Kenya, Uganda, Tanzania, Rwanda, Burundi and South Sudan into various forms of economic partnership, the eventual dream being to achieve political federation. The current activities within this community, plus the block’s further development, require the generation and sharing of much geo-information to support the attendant decision-making. Such geo-information can be best served through a harmonized cartographic service with common standards. Such a harmonized service is not only lacking, but even the status of the current national services is also largely unknown. This paper reports on a study undertaken to establish this status, as represented by twelve elements of a cartographic service that the authors are able to establish. Results of the study have shown that the present national services are characterized by inadequate basic datasets that remain largely analogue. In addition, there are non-uniform spatial reference systems, inadequate cartographic human resources and lack of common mapping standards;further, funding for mapping activities remains low in national budgets. Given that over 80% of decisions are influenced by geo-spatial data, these findings point to an urgent need to improve, harmonize and digitize these services as the way forward, if the East African Community is to remain globally competitive.
文摘In this paper, Land at 8 OLI image data from 2013 to 2017 was interpreted by visual interpretation combined with supervised classification to extract the information of land use distribution in the Yellow River Delta in China. The characteristics of Land Use Cover Change (LUCC) in the past five years which were analyzed by land use spatial analysis method based on buffer zone were discussed to obtain the land use index trend of five land types in buffer zones at different distance. The land use transfer maps of 2013 and 2017 were made by using the geo-information mapping method. The spatial-temporal change rules and the development process of land use in the Yellow River Delta during the past five years were analyzed. According to the analysis results, the comprehensive index of land use degree in the study area was in the middle level. The land use transfer maps were mainly consisted of farmland and grassland. The change rate of bare land to vegetation was 20.21% and that of vegetation to bare land was 14.15%. This study can provide effective basis for the scientific management of land and rational guidance for planning in this area.
基金Special Funds for the Major State Basic Research Project (Grant Nos. 2002CB412408 and G2000077903)National Natural Science Foundation of China (Grant Nos. 40371093 and 40471097)+1 种基金 Opening Fund Projects of the State Key Laboratory of Estuarine and Coastal Research of East China Normal University (Grant No. 0310)Opening Fund Projects of the State Key Laboratory of Remote Sensing Science in the Institute of Remote Sensing Applications (Grant No. SK040006)
文摘Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process in landscape ecology, the methodology of landscape information Tupu in studying the swing process of the Yellow River (YR) over the Yellow River Delta (YRD) during 1855― 2000 has been demonstrated. The main content includes: (1) methodology of landscape information Tupu; (2) evolution process Tupu of YR rump channels; (3) evolution process Tupu of the 7 pieces of subdeltas in YRD during 1855―2000; (4) landscape information Tupu of the modern YRD and the current YRD; (5) landscape information Tupu of YR rump channels on the 7 pieces of subdeltas during 1855―2000; and (6) corridor-matrix landscape information Tupu by YR swings. The methodology of landscape information Tupu here is still primary but we hope that it could provide a new tool for exploring an integrated research on spatiotemporal approaches for landscape "pattern and process".
基金Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA19040302The Key Research Program of the Chinese Academy of Sciences,No.KFZD-SW-111
文摘A model integrating geo-information and self-organizing map(SOM) for exploring the database of soil environmental surveys was established. The dataset of 5 heavy metals(As, Cd, Cr, Hg, and Pb) was built by the regular grid sampling in Hechi, Guangxi Zhuang Autonomous Region in southern China. Auxiliary datasets were collected throughout the study area to help interpret the potential causes of pollution. The main findings are as follows:(1) Soil samples of 5 elements exhibited strong variation and high skewness. High pollution risk existed in the case study area, especially Hg and Cd.(2) As and Pb had a similar topological distribution pattern, meaning they behaved similarly in the soil environment. Cr had behaviours in soil different from those of the other 4 elements.(3) From the U-matrix of SOM networks, 3 levels of SEQ were identified, and 11 high risk areas of soil heavy metal-contaminated were found throughout the study area, which were basically near rivers,factories, and ore zones.(4) The variations of contamination index(CI) followed the trend of construction land(1.353)> forestland(1.267)> cropland(1.175)> grassland(1.056), which suggest that decision makers should focus more on the problem of soil pollution surrounding industrial and mining enterprises and farmland.