The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remo...The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remote sensing(RS)and geographic information system(GIS)provides data sources and processing platform for RECC monitoring.This study analyzed and established the evaluation index system of RECC by considering particularity in the karst mountainous area of Southwest China;processed multisource RS data(Sentinel-2,Aster-DEM and Landsat-8)to extract the spatial distributions of nine key indexes by GIS techniques(information classification,overlay analysis and raster calculation);proposed the methods of index integration and fuzzy comprehensive evaluation of the RECC by GIS;and took a typical area,Guangnan County in Yunnan Province of China,as an experimental area to explore the effectiveness of the indexes and methods.The results showed that:(1)The important indexes affecting the RECC of karst mountainous area are water resources,tourism resources,position resources,geographical environment and soil erosion environment.(2)Data on cultivated land,construction land,minerals,transportation,water conservancy,ecosystem services,topography,soil erosion and rocky desertification can be obtained from RS data.GIS techniques integrate the information into the RECC results.The data extraction and processing methods are feasible on evaluating RECC.(3)The RECC of Guangnan County was in the mid-carrying level in 2018.The midcarrying and low-carrying levels were the main types,accounting for more than 80.00%of the total study area.The areas with high carrying capacity were mainly distributed in the northern regions of the northwest-southeast line of the county,and other areas have a low carrying capacity comparatively.The coordination between regional resource-environment status and socioeconomic development is the key to improve RECC.This study explores the evaluation index system of RECC in karst mountainous area and the application of multisource RS data and GIS techniques in the comprehensive evaluation.The methods can be applied in related fields to provide suggestions for data/information extraction and integration,and sustainable development.展开更多
Hypsometric analysis is considered an effective tool for understanding the stages of geomorphic evolution and geological development of river catchment, and for the delineation of erosional proneness of watershed. In ...Hypsometric analysis is considered an effective tool for understanding the stages of geomorphic evolution and geological development of river catchment, and for the delineation of erosional proneness of watershed. In the present study, twenty eight fourth order sub-basins of W. Mujib-Wala (Southern Jordan) were selected, and hypsometric analysis was carried out using 30 m ASTER DEM. Elevation-relief ratio method was employed to calculate the hypsometric integral values within GIS environment. The hypsometric integral values range from 0.71 to 0.88, whereas, the hypsometric curves exhibit remarkably upward convex shapes which indicate that all sub-basins and the W. Mujib-Wala watershed are at the youth-age stage of geomorphic development. Thus, they are of high susceptibility to erosion, incised channel erosion and mass movement activity. Marginal differences exist in mass removal from the watershed and the 28 sub-basins are attributed to variation in tectonic effect, lithology and rejuvenation processes. The relation between basin area and hypsometric integral was examined using regression analysis. Results reveal that negative and weak relationships dominate, where r<sup>2</sup> ranges from 0.05 to 0.478 which confirm with other results reported elsewhere. Indirect assessment of erosion status based on hypsometric integral values was validated using estimated sediment yield information related to wadi Mujib and wadi Wala watersheds separately. The recorded sediment yields were in affirmation with high hypsometric integrals values, where higher values of hypsometric integrals and sediment yields occurred in the western part of the W. Mujib-Wala watershed. These findings would help in the construction of appropriate soil and water conservation measures across the watershed and its sub-basins to control soil erosion, to conserve water, and to reduce sediment discharge into the W. Mujib and W. Wala reservoirs.展开更多
West Jilin Province" in this paper means Zhenlai, Baicheng, Taonan, Da′an, Tongyu, Fuyu, Songyuan, Qian′an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping and Nong′an which have been suffered ...West Jilin Province" in this paper means Zhenlai, Baicheng, Taonan, Da′an, Tongyu, Fuyu, Songyuan, Qian′an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping and Nong′an which have been suffered from desertification. In west Jilin Province there are three sand zones passing through, they are Xiang(Xianghai) Wu(Ulan Tug) sand zone, Hai Feng sand zone, and Tao′er River right bank sand zone. The desertification area of west Jilin Province is 819 100 ha, making up 12.5% of the total land area. Among desertification types, in Jilin Province light desertification is the major, then is medium dersertification, hevey desertification is the least.According to the comparison of the interpretation results of the Landsat images of the 1980s and the 1990s by remote sensing and GIS techniques, it can be seen that the desertification area in west Jilin Province basically didn′t change on the whole, only increased 6130 ha, making up 0.8% of the desertification area, change scale is less than 1%. Evidently, desertification is controlled mostly, but some areas are continuing deterioration.The desertification process of China can be divided into three types according to origin nature, they are sandy steppe desertification, fixed sand area(sand land) activation and dunes transfer invasion.Reasons of desertification of West Jilin Province are analyzed, they include natural factors(such as material source factors, chimate factors) and artificial factors(such as destroying grass to reclaim, steppe decreasing greatly, illegally feeling shelter forest stands, constructing reservoir to influence eco environment etc.). Some suggestions are put forward as follows: establishing the social project for ecological reconstruction of degenerated land; intensifying planning and management of land use, reverting farmland into forestland or pasture in a planned way. The key desertification control is to depend mainly on policy and management, then control techniques.展开更多
The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science.A good database structure is important to the integration of RS with GIS,which should ...The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science.A good database structure is important to the integration of RS with GIS,which should be beneficial to the complete integration of RS with GIS,able to deal with the disagreement between the resolution of remote sensing images and the precision of GIS data,and also helpful to the knowledge discovery and exploitation.In this paper,the database structure storing the spatial data based on semantic network is presented.This database structure has several advantages.Firstly,the spatial data is stored as raster data with space index,so the image processing can be done directly on the GIS data that is stored hierarchically according to the distinguishing precision.Secondly,the simple objects are aggregated into complex ones.Thirdly,because we use the indexing tree to depict the relationship of aggregation and the indexing pictures expressed by 2_D strings to describe the topology structure of the objects,the concepts of surrounding and region are expressed clearly and the semantic content of the landscape can be illustrated well.All the factors that affect the recognition of the objects are depicted in the factor space,which provides a uniform mathematical frame for the fusion of the semantic and non_semantic information.Lastly,the object node,knowledge node and the indexing node are integrated into one node.This feature enhances the ability of system in knowledge expressing,intelligent inference and association.The application shows that this database structure can benefit the interpretation of remote sensing image with the information of GIS.展开更多
基金the support given by the government and official in Guangnan Countyfunded by[National Natural Science Foundation of China]grant number[41361020,40961031]+3 种基金[Joint Fund of Yunnan Provincial Science and Technology Department and Yunnan University]grant number[2018FY001(-017)][Project of Innovative Talents Cultivation for Graduate Students of Yunnan University]grant number[C176230200][Project of Internationalization and Cultural Inheritance and Innovation of Yunnan University]grant number[C176250202][Science Research Fund of Yunnan Provincial Education Department in 2020:Postgraduate]grant number[2020Y0030]。
文摘The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remote sensing(RS)and geographic information system(GIS)provides data sources and processing platform for RECC monitoring.This study analyzed and established the evaluation index system of RECC by considering particularity in the karst mountainous area of Southwest China;processed multisource RS data(Sentinel-2,Aster-DEM and Landsat-8)to extract the spatial distributions of nine key indexes by GIS techniques(information classification,overlay analysis and raster calculation);proposed the methods of index integration and fuzzy comprehensive evaluation of the RECC by GIS;and took a typical area,Guangnan County in Yunnan Province of China,as an experimental area to explore the effectiveness of the indexes and methods.The results showed that:(1)The important indexes affecting the RECC of karst mountainous area are water resources,tourism resources,position resources,geographical environment and soil erosion environment.(2)Data on cultivated land,construction land,minerals,transportation,water conservancy,ecosystem services,topography,soil erosion and rocky desertification can be obtained from RS data.GIS techniques integrate the information into the RECC results.The data extraction and processing methods are feasible on evaluating RECC.(3)The RECC of Guangnan County was in the mid-carrying level in 2018.The midcarrying and low-carrying levels were the main types,accounting for more than 80.00%of the total study area.The areas with high carrying capacity were mainly distributed in the northern regions of the northwest-southeast line of the county,and other areas have a low carrying capacity comparatively.The coordination between regional resource-environment status and socioeconomic development is the key to improve RECC.This study explores the evaluation index system of RECC in karst mountainous area and the application of multisource RS data and GIS techniques in the comprehensive evaluation.The methods can be applied in related fields to provide suggestions for data/information extraction and integration,and sustainable development.
文摘Hypsometric analysis is considered an effective tool for understanding the stages of geomorphic evolution and geological development of river catchment, and for the delineation of erosional proneness of watershed. In the present study, twenty eight fourth order sub-basins of W. Mujib-Wala (Southern Jordan) were selected, and hypsometric analysis was carried out using 30 m ASTER DEM. Elevation-relief ratio method was employed to calculate the hypsometric integral values within GIS environment. The hypsometric integral values range from 0.71 to 0.88, whereas, the hypsometric curves exhibit remarkably upward convex shapes which indicate that all sub-basins and the W. Mujib-Wala watershed are at the youth-age stage of geomorphic development. Thus, they are of high susceptibility to erosion, incised channel erosion and mass movement activity. Marginal differences exist in mass removal from the watershed and the 28 sub-basins are attributed to variation in tectonic effect, lithology and rejuvenation processes. The relation between basin area and hypsometric integral was examined using regression analysis. Results reveal that negative and weak relationships dominate, where r<sup>2</sup> ranges from 0.05 to 0.478 which confirm with other results reported elsewhere. Indirect assessment of erosion status based on hypsometric integral values was validated using estimated sediment yield information related to wadi Mujib and wadi Wala watersheds separately. The recorded sediment yields were in affirmation with high hypsometric integrals values, where higher values of hypsometric integrals and sediment yields occurred in the western part of the W. Mujib-Wala watershed. These findings would help in the construction of appropriate soil and water conservation measures across the watershed and its sub-basins to control soil erosion, to conserve water, and to reduce sediment discharge into the W. Mujib and W. Wala reservoirs.
文摘West Jilin Province" in this paper means Zhenlai, Baicheng, Taonan, Da′an, Tongyu, Fuyu, Songyuan, Qian′an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping and Nong′an which have been suffered from desertification. In west Jilin Province there are three sand zones passing through, they are Xiang(Xianghai) Wu(Ulan Tug) sand zone, Hai Feng sand zone, and Tao′er River right bank sand zone. The desertification area of west Jilin Province is 819 100 ha, making up 12.5% of the total land area. Among desertification types, in Jilin Province light desertification is the major, then is medium dersertification, hevey desertification is the least.According to the comparison of the interpretation results of the Landsat images of the 1980s and the 1990s by remote sensing and GIS techniques, it can be seen that the desertification area in west Jilin Province basically didn′t change on the whole, only increased 6130 ha, making up 0.8% of the desertification area, change scale is less than 1%. Evidently, desertification is controlled mostly, but some areas are continuing deterioration.The desertification process of China can be divided into three types according to origin nature, they are sandy steppe desertification, fixed sand area(sand land) activation and dunes transfer invasion.Reasons of desertification of West Jilin Province are analyzed, they include natural factors(such as material source factors, chimate factors) and artificial factors(such as destroying grass to reclaim, steppe decreasing greatly, illegally feeling shelter forest stands, constructing reservoir to influence eco environment etc.). Some suggestions are put forward as follows: establishing the social project for ecological reconstruction of degenerated land; intensifying planning and management of land use, reverting farmland into forestland or pasture in a planned way. The key desertification control is to depend mainly on policy and management, then control techniques.
文摘The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science.A good database structure is important to the integration of RS with GIS,which should be beneficial to the complete integration of RS with GIS,able to deal with the disagreement between the resolution of remote sensing images and the precision of GIS data,and also helpful to the knowledge discovery and exploitation.In this paper,the database structure storing the spatial data based on semantic network is presented.This database structure has several advantages.Firstly,the spatial data is stored as raster data with space index,so the image processing can be done directly on the GIS data that is stored hierarchically according to the distinguishing precision.Secondly,the simple objects are aggregated into complex ones.Thirdly,because we use the indexing tree to depict the relationship of aggregation and the indexing pictures expressed by 2_D strings to describe the topology structure of the objects,the concepts of surrounding and region are expressed clearly and the semantic content of the landscape can be illustrated well.All the factors that affect the recognition of the objects are depicted in the factor space,which provides a uniform mathematical frame for the fusion of the semantic and non_semantic information.Lastly,the object node,knowledge node and the indexing node are integrated into one node.This feature enhances the ability of system in knowledge expressing,intelligent inference and association.The application shows that this database structure can benefit the interpretation of remote sensing image with the information of GIS.
