Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,China.The objective of this study was to improve our under...Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,China.The objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be established.An environmental numerical model was developed using spatial principal component analysis(SPCA)model.The model contains twelve factors that include variables of land use,soil erosion,topography,climate,and vegetation.Using this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2000 for the Yellow River Basin.The SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2000 were analyzed and the driving factors of eco-environmental changes were investigated.The results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the whole.However,the eco-environmental quality had become worse over the ten years in some regions.In the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years.展开更多
Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture ...Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard.展开更多
The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-m...The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.展开更多
In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can...In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can make P2P systems enhance overall reliability and fault-tolerance, increase autonomy, and enable ad-hoc communication and collaboration. On the other hand, Web services provides a good approach to integrate various heterogeneous systems and applications into a cooperative environment. This paper presents the techniques of combining Web services and P2P technologies into GIS to construct a new generation of GIS, which is more flexible and cooperative. As a case study, an ongoing project JGWS is introduced, which is an experimental GIS Web services platform built on JXTA. This paper also explores the schemes of building GIS Web services in a P2P environment.展开更多
The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM+ images with no cloud cover from July/Au...The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM+ images with no cloud cover from July/August in different years (1990, 1995, 2000 and 2005) were used to analyze the change in various land environmental factors over time. The results show that while mining activity initially had a marked adverse impact on the environment, mine rehabilitation measures have also subsequently played a great role in improving vegetation cover and controlling land desertification and loss of water and soil. The effect of coal mining on vegetation cover is dependent upon the soil type and natural indigenous flora. Results of this investigation imply that mining activity has a greater effect on the vegetation of loess areas than at sandy sites. Although local vegetation coverage was improved by planting in the mining area, the total area of land affected by desertification still in- creased from 26.81% in 1990 when large-scale mine construction was introduced, to 46.79% in 1995. With continuous efforts at rehabilitation, the vegetation cover in the Shendong coal mining area was increasing, and loss of water and soil were effec- tively controlled since 1995. Subsequently, the total area of extreme desertification decreased to 23.24% in 2000 and further to 18.68% in 2005. The total area affected by severe loss of water and soil also decreased since the early 1990's (70.61% in 1990, 71.43% in 1995), to 43.64% in 2000 and 34.93% in 2005, respectively.展开更多
Global research progress on coastal flooding was studied using a bibliometric evaluation of publications listed in the Web of Science extended scientific citation index. There was substantial growth in coastal floodin...Global research progress on coastal flooding was studied using a bibliometric evaluation of publications listed in the Web of Science extended scientific citation index. There was substantial growth in coastal flooding research output, with increasing publications, a higher collaboration index, and more references during the 1995–2016 period. The USA has taken a dominant position in coastal flooding research, with the US Geological Survey leading the publications ranking. Research collaborations at institutional scales have become more important than those at global scales. International collaborative publications consistently drew more citations than those from a single country. Furthermore, coastal flooding research included combinations of multi-disciplinary categories, including ‘Geology' and ‘Environmental Sciences & Ecology'. The most important coastal flooding research sites were wetlands and estuaries. While numerical modeling and 3 S(Remote sensing, RS; Geography information systems, GIS; Global positioning systems, GPS) technology were the most commonly used methods for studying coastal flooding, Lidar gained in popularity. The vulnerability and adaptation of coastal environments, their resilience after flooding, and ecosystem services function showed increases in interest.展开更多
The remote sensing image classification has stimulated considerable interest as an effective method for better retrieving information from the rapidly increasing large volume, complex and distributed satellite remote ...The remote sensing image classification has stimulated considerable interest as an effective method for better retrieving information from the rapidly increasing large volume, complex and distributed satellite remote imaging data of large scale and cross-time, due to the increase of remote image quantities and image resolutions. In the paper, the genetic algorithms were employed to solve the weighting of the radial basis faction networks in order to improve the precision of remote sensing image classification. The remote sensing image classification was also introduced for the GIS spatial analysis and the spatial online analytical processing (OLAP), and the resulted effectiveness was demonstrated in the analysis of land utilization variation of Daqing city.展开更多
Embedded ArcGIS Engine can improve development efficiency of environmental information system. The authors designed the structure, functions and database of the Yongjiang River Basin Water Environment Management Infor...Embedded ArcGIS Engine can improve development efficiency of environmental information system. The authors designed the structure, functions and database of the Yongjiang River Basin Water Environment Management Information System (YRBWEMIS) through the integration of ArcGIS Engine software with VC. The spatial data and attribute data in the YRBWEMIS are stored and managed separately. The system functions include display, query, statistics, spatial analysis and thematic mapping for water pollution sources, water quality, water function regionalization and catchments region.展开更多
Based on previot, s stt,dies on Panjin wetlands along the coast of the Bohai Sea, this paper adopts RS, GIS and GPS techniques and establishes the information system for Panjin wetlands. The system involves many funct...Based on previot, s stt,dies on Panjin wetlands along the coast of the Bohai Sea, this paper adopts RS, GIS and GPS techniques and establishes the information system for Panjin wetlands. The system involves many functions, such as identification and classification of wetlands, calculation of the area of wetlands and storage of the information of the wetland management. Moreover, our study indicates that remote sensing technique is a useful tool for great macrography, speediness and accuracy to carry out the extraction, analysis, management and handling of information together with geography information system, which has prospective applications in similar kinds of research.展开更多
The urban environmental quality remains currently difficult to be assessed because of overlapping of several natural and anthropogenic factors having socio-economic and environmental outstanding impacts. The fast deve...The urban environmental quality remains currently difficult to be assessed because of overlapping of several natural and anthropogenic factors having socio-economic and environmental outstanding impacts. The fast developing and uncontrolled urbanization is behind the development of some negative side effects on the urban environment. Many studies demonstrate the ability of remote sensing and GIS (geographic information system) to monitor urban environment quality. Casablanca, Morocco's economical capital is facing a fast growing demographic development amplified by a massive rural depopulation and all this in an anarchic way. This growth of increased urban activity comes often with the proliferation of informal settlement and shantytown to the detriment of farming areas and green spaces. This study is made possible by using a SPOT-5 image of Casablanca city, taken March 16, 2004 merged with 2.5 m spatial resolution and census data. Indicators were defined and listed in social, economic and environmental categories. An index of environmental quality in Casablanca city for the 17 urban municipalities was calculated after the standardization and weighting of indicators used. The results may be useful to city managers and planners who are concerned with urban environment quality issues and sustainable development.展开更多
Geographic information systems (GIS) are a widely used tool in urban planning and management. More and more cities and decision-makers require its attributes of promptness, precision and visualization. But the applica...Geographic information systems (GIS) are a widely used tool in urban planning and management. More and more cities and decision-makers require its attributes of promptness, precision and visualization. But the application of GIS in urban environmental management is still a new field and relevant researches are getting on tardily. As a subsystem of GIS, an urban environmental management geographic information system (UEMGIS) should be a complex multi-discipline and multi-objective tool to perform quantitative multi-dimension analysis and to transfer the results into an expression legible to an ordinary user. It should be a dynamic system of prompt functions based on upgradable databases, and be composed of many subsystems respectively specialized in items about water, air, waste and noise as well as relative standards and regulations. However, existing UEMGISs mostly rely on the basic GIS too much to design the actual requirements of applications and managements in themselves, and the unavailability of sufficient fundamental data has retarded their improvement. In the design of a UEMGIS, the standardization of data classification should be taken into consideration to make the data exchangeable and shareable among its subsystems and within every subsystem, and the applicable error limits for input data should be defined in accordance with the user抯 required precision of data out. Data acquisition can be easy and quick if remote sensing, global positioning system (GPS) and other technologies are combined with GIS. Rapidly progressing information technologies have been giving a bright prospect for the melioration of UEMGIS that will have great potential and wide application in environmental conservation.展开更多
Nepal is one of the top three exporters of larger cardamom (Amomum subulatum Roxb.) in the world market contributing largely to the Nepalese economy. Sub-Himalayan range of hilly area of eastern Nepal is popular for...Nepal is one of the top three exporters of larger cardamom (Amomum subulatum Roxb.) in the world market contributing largely to the Nepalese economy. Sub-Himalayan range of hilly area of eastern Nepal is popular for large cardamom cultivation. Being similar phytogeographical and ecological setting, cultivation has begun in hills of Kathmandu Valley however land suitability needs to be evaluated with reference to specific need of the crop. Kathmandu is a valley with alluvial bottom and altitudinal range between 1200 and 2730m above sea level having cool to warm temperate climatic range. Varieties of aspects and slope gradient have potentiality for the large cardamom cultivation. Aim of the study was set to categorize available land area in the range of suitability for large cardamon cultivation on the basis of physical characteristics of the land and ecological need of crop. Land evaluation methodology has been designed along with site specific amendment in FAO framework (1976). Land use map in scale of 1:25 000 was used in geographic information system environment. Suitability was done through map overlaying methods. Aim of the study was set to categorize available land area in the range of suitability categories for large cardamom cultivation based on physical characteristics of the land matching with ecological need of crop. Analysis of data shows that altitudinal range at uplands of Kathmandu Valley and annual average rainfall and temperature are found to be within suitability range for Amomum subulaturn cultivation. Sandy loam soil, slightly acidic in nature with gentle sloping land of about 5-8° provides highly suitable condition. Result showed that more than one-third of total land area above 1800 m of altitude is suitable. Selectively, of the total area, 5% are north facing slope, 13% gentle slopes are highly suitable. 16% lands with north east orientation are moderately suitable. Most of the land areas which are marginaly suitabile for vegetable and cereal crops are highly suitable for large cardamom. Hills of northern boundary hills found to be suitable due to more rainfall distribution pattern compared to southern boundary hills. Therefore, land evaluation also identifies limitations and input requirements for sustainable production.展开更多
The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the out...The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the outdoor thermal environment, monitoring data and simulating data. A prediction and evaluation system were set up. A typical mountainous city, i.e., Yunyang city in Chongqing in China, was taken as an example, its urbanization trend and population growth was predicted and evaluated. The heat island intensity and its trend were simulated, the temperature field, velocity field and the humidity field were analyzed. The results show that GIS is an effective tool to deal with the outdoor thermal environment, especially for the mountainous cities with special geographical particularities. GIS can be used in the environmental management and the city planning especially for the mountainous cities.展开更多
Influenced by artificial factors, landscape pattern of Yantai City, Shandong Province changes continuously. Revealing its landscape pattern and its changing process has a practical significance for the urban developme...Influenced by artificial factors, landscape pattern of Yantai City, Shandong Province changes continuously. Revealing its landscape pattern and its changing process has a practical significance for the urban development and layout. Zhifu District, Development Zone, Laishan District and Fushan District in Yantai City were selected to study the landscape pattern. Remote sensing technology was used to obtain landscape information of different periods. Under the support of Geographic Information System (GIS), the spatial landscape pattern of Yantai City was analyzed and simulated by using various special quantitative analysis models. The analysis shows that built-up area lies in the center of Yantai City, the outside is vegetable land, irrigated land, dry land, garden land and woodland.展开更多
The aim of this research is to identify the most suitable land for forestry, afforestation and rangeland management in Hamadan province. This research has been accomplished using Makhdoum's model. In this research 30...The aim of this research is to identify the most suitable land for forestry, afforestation and rangeland management in Hamadan province. This research has been accomplished using Makhdoum's model. In this research 30 digital data layers are used. The Geographic Information System (GIS) has been used as main tool and overlay method has been used to implement the mentioned model. The results of this research revealed that the extent of favorite areas for fifth grade forestry, favorite areas for fourth grade afforestation, and favorite areas for third grade and fourth grade range management in the studied area. Based on the results of this research, the studied area has limited potentials for forestry and afforestation activities. The obtained results of evaluation also showed that the rangelands of Hamadan province are extremely poor. Since the rangelands have a substantial role in preservation of soil and water, therefore it is necessary to take appropriate measures for better exploitation of rangelands.展开更多
Lebanon, the water tower, occupies 15 permanent watercourses, i.e., rivers, locally the so-called "Naher". Likewise most of the Lebanese rivers, EI-Assi River or the Orontes River is witnessing indicatives of pollut...Lebanon, the water tower, occupies 15 permanent watercourses, i.e., rivers, locally the so-called "Naher". Likewise most of the Lebanese rivers, EI-Assi River or the Orontes River is witnessing indicatives of pollution. While it represents a vital vein in north of the Bekaa valley, a spectrum of pollutant sources is known to increase this geo-environmental problem. Hence, this study aims to give first-hand information on the parameters involved in the pollution problem, as a concept figure for further deal. Certainly, its objective is to end up with thematic maps pointing out to suitable localities for monitoring activities on the river tributaries.展开更多
In order to improve the use efficiency of environmental data intbrmation which has existed and to be produced, correctly control the situation of the regional environmental pollution, and supervise the regional en...In order to improve the use efficiency of environmental data intbrmation which has existed and to be produced, correctly control the situation of the regional environmental pollution, and supervise the regional environmental pollution recovery and urban planning, the paper crests the main-elements analysis module based on Super-Map GIS, beyond which, using the information of environmental pollution discharge data of some typical areas of Beijing. The paper analyses those representative regional environmental discharge data by the systemic main-clements analysis module, speedily discoveries and explains the regional environmental major control factors in the studying region. According to the special points of social, economical and environmental in the region, the paper gives out the improvement policies of regional environmental quality and practicable environmental engineering disposed project. This research not only indicates the development direction of the urban environmental management, but also builds up a main frame of the urban environmental planning. This paper and its relative works provide an efficiently digital management tool for the urban regional environmental management and explore the feasible method and mode for the improvement of urban regional environmental quality.展开更多
GIS (geographic information systems) is often used for planning purposes in forestry. This is mainly used to give directives for the operators to cut the trees. And nowadays, it is also used for marking of areas wit...GIS (geographic information systems) is often used for planning purposes in forestry. This is mainly used to give directives for the operators to cut the trees. And nowadays, it is also used for marking of areas with high environmental values where considerations should be made. The minor used techniques is to incorporate soil information maps as an overlay to give information to forest machine operators where less good trafficability is to be expected, especially after a heavy rain. By marking areas with bad bearing capacity, the operators may save both time and money, and do not bog down with the machine. When the soils bearing capacity is less than 0.7 MPa and the ground pressure of the machine is more than 80 kPa, either smaller machines must be used or bogey tracks should be used to decrease the risk for getting stuck or causing severe rutting. By choosing good types of bogey tracks both rutting and fuel consumption will be decreased for the health of forest land and the contractor.展开更多
Elucidation of the relationships between genetic polymorphisms and environmental exposures can provide insights into the pathways and mechanisms underlying complex traits. A new approach was used to detect G×E (...Elucidation of the relationships between genetic polymorphisms and environmental exposures can provide insights into the pathways and mechanisms underlying complex traits. A new approach was used to detect G×E (gene-environment) interactions involved in human skin pigmentation variation to better understand the adaptive evolution of skin pigmentation. Specifically, we used genetic engineering, remote UVR (ultraviolet radiation) sensing and GIS (geographic information systems) to integrate the analysis of genetic and environmental factors into a coherent biological framework. Since we expected to generate large datasets for this multidimensional analysis, we used PCA (principal components analysis) as a spatial statistical analysis technique for analyzing the G×E interactions. The results suggest that skin pigmentation may be affected by mutations induced by UVR and support the hypothesis that global variation in skin pigmentation may be the result of localized adaptation to different UVR conditions via natural selection. Analyzing the relationships between heterozygous frequencies for SNP (single nucleotide polymorphism) loci and seasonal UVR levels as the environment changes will help elucidate the selective mechanisms involved in the UVR-induced evolution of skin pigmentation. Skin pigmentation fulfills the criteria for a successful evolutionary G×E interactions model.展开更多
基金the National Key Basic Research Support Foundation of China(973 Program)(No.2005CB422003)the National Natural Science Foundation of China(No.40571037)
文摘Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,China.The objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be established.An environmental numerical model was developed using spatial principal component analysis(SPCA)model.The model contains twelve factors that include variables of land use,soil erosion,topography,climate,and vegetation.Using this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2000 for the Yellow River Basin.The SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2000 were analyzed and the driving factors of eco-environmental changes were investigated.The results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the whole.However,the eco-environmental quality had become worse over the ten years in some regions.In the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years.
基金Funded by the National Natural Science Foundation of China (No.40341011) and the National 863 Program of China(No.2002AA135230)
文摘Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard.
文摘The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.
文摘In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can make P2P systems enhance overall reliability and fault-tolerance, increase autonomy, and enable ad-hoc communication and collaboration. On the other hand, Web services provides a good approach to integrate various heterogeneous systems and applications into a cooperative environment. This paper presents the techniques of combining Web services and P2P technologies into GIS to construct a new generation of GIS, which is more flexible and cooperative. As a case study, an ongoing project JGWS is introduced, which is an experimental GIS Web services platform built on JXTA. This paper also explores the schemes of building GIS Web services in a P2P environment.
文摘The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM+ images with no cloud cover from July/August in different years (1990, 1995, 2000 and 2005) were used to analyze the change in various land environmental factors over time. The results show that while mining activity initially had a marked adverse impact on the environment, mine rehabilitation measures have also subsequently played a great role in improving vegetation cover and controlling land desertification and loss of water and soil. The effect of coal mining on vegetation cover is dependent upon the soil type and natural indigenous flora. Results of this investigation imply that mining activity has a greater effect on the vegetation of loess areas than at sandy sites. Although local vegetation coverage was improved by planting in the mining area, the total area of land affected by desertification still in- creased from 26.81% in 1990 when large-scale mine construction was introduced, to 46.79% in 1995. With continuous efforts at rehabilitation, the vegetation cover in the Shendong coal mining area was increasing, and loss of water and soil were effec- tively controlled since 1995. Subsequently, the total area of extreme desertification decreased to 23.24% in 2000 and further to 18.68% in 2005. The total area affected by severe loss of water and soil also decreased since the early 1990's (70.61% in 1990, 71.43% in 1995), to 43.64% in 2000 and 34.93% in 2005, respectively.
基金Under the auspices of National Natural Science Foundation of China(No.41571018)
文摘Global research progress on coastal flooding was studied using a bibliometric evaluation of publications listed in the Web of Science extended scientific citation index. There was substantial growth in coastal flooding research output, with increasing publications, a higher collaboration index, and more references during the 1995–2016 period. The USA has taken a dominant position in coastal flooding research, with the US Geological Survey leading the publications ranking. Research collaborations at institutional scales have become more important than those at global scales. International collaborative publications consistently drew more citations than those from a single country. Furthermore, coastal flooding research included combinations of multi-disciplinary categories, including ‘Geology' and ‘Environmental Sciences & Ecology'. The most important coastal flooding research sites were wetlands and estuaries. While numerical modeling and 3 S(Remote sensing, RS; Geography information systems, GIS; Global positioning systems, GPS) technology were the most commonly used methods for studying coastal flooding, Lidar gained in popularity. The vulnerability and adaptation of coastal environments, their resilience after flooding, and ecosystem services function showed increases in interest.
基金Sponsored by the National Natural Science Foundation of China (Grant No.40271044), Natural Science Foundation(Grant No.TK2005 -17) and Projectof Science Backbone of Heilongjiang Province(Grant No.1151G021).
文摘The remote sensing image classification has stimulated considerable interest as an effective method for better retrieving information from the rapidly increasing large volume, complex and distributed satellite remote imaging data of large scale and cross-time, due to the increase of remote image quantities and image resolutions. In the paper, the genetic algorithms were employed to solve the weighting of the radial basis faction networks in order to improve the precision of remote sensing image classification. The remote sensing image classification was also introduced for the GIS spatial analysis and the spatial online analytical processing (OLAP), and the resulted effectiveness was demonstrated in the analysis of land utilization variation of Daqing city.
文摘Embedded ArcGIS Engine can improve development efficiency of environmental information system. The authors designed the structure, functions and database of the Yongjiang River Basin Water Environment Management Information System (YRBWEMIS) through the integration of ArcGIS Engine software with VC. The spatial data and attribute data in the YRBWEMIS are stored and managed separately. The system functions include display, query, statistics, spatial analysis and thematic mapping for water pollution sources, water quality, water function regionalization and catchments region.
基金the Special Doctorate Science Foundation of the Ministry of Education (Number200601570011)Liaoning Supporting Plan for Excellent Talents (No 2006-124)
文摘Based on previot, s stt,dies on Panjin wetlands along the coast of the Bohai Sea, this paper adopts RS, GIS and GPS techniques and establishes the information system for Panjin wetlands. The system involves many functions, such as identification and classification of wetlands, calculation of the area of wetlands and storage of the information of the wetland management. Moreover, our study indicates that remote sensing technique is a useful tool for great macrography, speediness and accuracy to carry out the extraction, analysis, management and handling of information together with geography information system, which has prospective applications in similar kinds of research.
文摘The urban environmental quality remains currently difficult to be assessed because of overlapping of several natural and anthropogenic factors having socio-economic and environmental outstanding impacts. The fast developing and uncontrolled urbanization is behind the development of some negative side effects on the urban environment. Many studies demonstrate the ability of remote sensing and GIS (geographic information system) to monitor urban environment quality. Casablanca, Morocco's economical capital is facing a fast growing demographic development amplified by a massive rural depopulation and all this in an anarchic way. This growth of increased urban activity comes often with the proliferation of informal settlement and shantytown to the detriment of farming areas and green spaces. This study is made possible by using a SPOT-5 image of Casablanca city, taken March 16, 2004 merged with 2.5 m spatial resolution and census data. Indicators were defined and listed in social, economic and environmental categories. An index of environmental quality in Casablanca city for the 17 urban municipalities was calculated after the standardization and weighting of indicators used. The results may be useful to city managers and planners who are concerned with urban environment quality issues and sustainable development.
基金Funded by National Nature Science Foundation of China (Nos. 59978054 and 59838300)
文摘Geographic information systems (GIS) are a widely used tool in urban planning and management. More and more cities and decision-makers require its attributes of promptness, precision and visualization. But the application of GIS in urban environmental management is still a new field and relevant researches are getting on tardily. As a subsystem of GIS, an urban environmental management geographic information system (UEMGIS) should be a complex multi-discipline and multi-objective tool to perform quantitative multi-dimension analysis and to transfer the results into an expression legible to an ordinary user. It should be a dynamic system of prompt functions based on upgradable databases, and be composed of many subsystems respectively specialized in items about water, air, waste and noise as well as relative standards and regulations. However, existing UEMGISs mostly rely on the basic GIS too much to design the actual requirements of applications and managements in themselves, and the unavailability of sufficient fundamental data has retarded their improvement. In the design of a UEMGIS, the standardization of data classification should be taken into consideration to make the data exchangeable and shareable among its subsystems and within every subsystem, and the applicable error limits for input data should be defined in accordance with the user抯 required precision of data out. Data acquisition can be easy and quick if remote sensing, global positioning system (GPS) and other technologies are combined with GIS. Rapidly progressing information technologies have been giving a bright prospect for the melioration of UEMGIS that will have great potential and wide application in environmental conservation.
文摘Nepal is one of the top three exporters of larger cardamom (Amomum subulatum Roxb.) in the world market contributing largely to the Nepalese economy. Sub-Himalayan range of hilly area of eastern Nepal is popular for large cardamom cultivation. Being similar phytogeographical and ecological setting, cultivation has begun in hills of Kathmandu Valley however land suitability needs to be evaluated with reference to specific need of the crop. Kathmandu is a valley with alluvial bottom and altitudinal range between 1200 and 2730m above sea level having cool to warm temperate climatic range. Varieties of aspects and slope gradient have potentiality for the large cardamom cultivation. Aim of the study was set to categorize available land area in the range of suitability for large cardamon cultivation on the basis of physical characteristics of the land and ecological need of crop. Land evaluation methodology has been designed along with site specific amendment in FAO framework (1976). Land use map in scale of 1:25 000 was used in geographic information system environment. Suitability was done through map overlaying methods. Aim of the study was set to categorize available land area in the range of suitability categories for large cardamom cultivation based on physical characteristics of the land matching with ecological need of crop. Analysis of data shows that altitudinal range at uplands of Kathmandu Valley and annual average rainfall and temperature are found to be within suitability range for Amomum subulaturn cultivation. Sandy loam soil, slightly acidic in nature with gentle sloping land of about 5-8° provides highly suitable condition. Result showed that more than one-third of total land area above 1800 m of altitude is suitable. Selectively, of the total area, 5% are north facing slope, 13% gentle slopes are highly suitable. 16% lands with north east orientation are moderately suitable. Most of the land areas which are marginaly suitabile for vegetable and cereal crops are highly suitable for large cardamom. Hills of northern boundary hills found to be suitable due to more rainfall distribution pattern compared to southern boundary hills. Therefore, land evaluation also identifies limitations and input requirements for sustainable production.
基金Project (50278099) supported by the National Natural Science Foundation of China
文摘The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the outdoor thermal environment, monitoring data and simulating data. A prediction and evaluation system were set up. A typical mountainous city, i.e., Yunyang city in Chongqing in China, was taken as an example, its urbanization trend and population growth was predicted and evaluated. The heat island intensity and its trend were simulated, the temperature field, velocity field and the humidity field were analyzed. The results show that GIS is an effective tool to deal with the outdoor thermal environment, especially for the mountainous cities with special geographical particularities. GIS can be used in the environmental management and the city planning especially for the mountainous cities.
文摘Influenced by artificial factors, landscape pattern of Yantai City, Shandong Province changes continuously. Revealing its landscape pattern and its changing process has a practical significance for the urban development and layout. Zhifu District, Development Zone, Laishan District and Fushan District in Yantai City were selected to study the landscape pattern. Remote sensing technology was used to obtain landscape information of different periods. Under the support of Geographic Information System (GIS), the spatial landscape pattern of Yantai City was analyzed and simulated by using various special quantitative analysis models. The analysis shows that built-up area lies in the center of Yantai City, the outside is vegetable land, irrigated land, dry land, garden land and woodland.
文摘The aim of this research is to identify the most suitable land for forestry, afforestation and rangeland management in Hamadan province. This research has been accomplished using Makhdoum's model. In this research 30 digital data layers are used. The Geographic Information System (GIS) has been used as main tool and overlay method has been used to implement the mentioned model. The results of this research revealed that the extent of favorite areas for fifth grade forestry, favorite areas for fourth grade afforestation, and favorite areas for third grade and fourth grade range management in the studied area. Based on the results of this research, the studied area has limited potentials for forestry and afforestation activities. The obtained results of evaluation also showed that the rangelands of Hamadan province are extremely poor. Since the rangelands have a substantial role in preservation of soil and water, therefore it is necessary to take appropriate measures for better exploitation of rangelands.
文摘Lebanon, the water tower, occupies 15 permanent watercourses, i.e., rivers, locally the so-called "Naher". Likewise most of the Lebanese rivers, EI-Assi River or the Orontes River is witnessing indicatives of pollution. While it represents a vital vein in north of the Bekaa valley, a spectrum of pollutant sources is known to increase this geo-environmental problem. Hence, this study aims to give first-hand information on the parameters involved in the pollution problem, as a concept figure for further deal. Certainly, its objective is to end up with thematic maps pointing out to suitable localities for monitoring activities on the river tributaries.
文摘In order to improve the use efficiency of environmental data intbrmation which has existed and to be produced, correctly control the situation of the regional environmental pollution, and supervise the regional environmental pollution recovery and urban planning, the paper crests the main-elements analysis module based on Super-Map GIS, beyond which, using the information of environmental pollution discharge data of some typical areas of Beijing. The paper analyses those representative regional environmental discharge data by the systemic main-clements analysis module, speedily discoveries and explains the regional environmental major control factors in the studying region. According to the special points of social, economical and environmental in the region, the paper gives out the improvement policies of regional environmental quality and practicable environmental engineering disposed project. This research not only indicates the development direction of the urban environmental management, but also builds up a main frame of the urban environmental planning. This paper and its relative works provide an efficiently digital management tool for the urban regional environmental management and explore the feasible method and mode for the improvement of urban regional environmental quality.
文摘GIS (geographic information systems) is often used for planning purposes in forestry. This is mainly used to give directives for the operators to cut the trees. And nowadays, it is also used for marking of areas with high environmental values where considerations should be made. The minor used techniques is to incorporate soil information maps as an overlay to give information to forest machine operators where less good trafficability is to be expected, especially after a heavy rain. By marking areas with bad bearing capacity, the operators may save both time and money, and do not bog down with the machine. When the soils bearing capacity is less than 0.7 MPa and the ground pressure of the machine is more than 80 kPa, either smaller machines must be used or bogey tracks should be used to decrease the risk for getting stuck or causing severe rutting. By choosing good types of bogey tracks both rutting and fuel consumption will be decreased for the health of forest land and the contractor.
文摘Elucidation of the relationships between genetic polymorphisms and environmental exposures can provide insights into the pathways and mechanisms underlying complex traits. A new approach was used to detect G×E (gene-environment) interactions involved in human skin pigmentation variation to better understand the adaptive evolution of skin pigmentation. Specifically, we used genetic engineering, remote UVR (ultraviolet radiation) sensing and GIS (geographic information systems) to integrate the analysis of genetic and environmental factors into a coherent biological framework. Since we expected to generate large datasets for this multidimensional analysis, we used PCA (principal components analysis) as a spatial statistical analysis technique for analyzing the G×E interactions. The results suggest that skin pigmentation may be affected by mutations induced by UVR and support the hypothesis that global variation in skin pigmentation may be the result of localized adaptation to different UVR conditions via natural selection. Analyzing the relationships between heterozygous frequencies for SNP (single nucleotide polymorphism) loci and seasonal UVR levels as the environment changes will help elucidate the selective mechanisms involved in the UVR-induced evolution of skin pigmentation. Skin pigmentation fulfills the criteria for a successful evolutionary G×E interactions model.