Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-tempora...Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-temporal Landsat TM and Landsat ETM+ data were employed to identify patterns of LUCC as well as to quantify urban expansion and the associated decrease of vegetation cover. The thermal infrared bands of the data were used to retrieve LST. The results revealed a strong and uneven urban growth,which caused LST to raise 4.56℃in the newly urbanized part of the study area. Overall, remote sensing and GIS technologies were effective approaches for monitoring and analyzing urban growth patterns and evaluating their impacts on LST.展开更多
Element contents of tree rings and soils near tree roots collected from Deodar cedar (Cedrus deodara (Roxb.) G. Don) and Masson pine (Picks massoniana lamb.) were determined to study the relationship between the angul...Element contents of tree rings and soils near tree roots collected from Deodar cedar (Cedrus deodara (Roxb.) G. Don) and Masson pine (Picks massoniana lamb.) were determined to study the relationship between the angular distribution of element contents in tree rings and the environmental information. The chemical composition and properties of soils are very much complicated, which leads to the non-uniform distribution of the element contents in tree rings. The statistical multi-variable regression method was used to got the information of the tree-centered distribution of element contents in the environment (soil) (C’), C’(z, θj ), from the distribution of element contents in tree rings (C), C(Z, θi), which depends on the plane azimuth angle (θi), i. e., C=C(Z,θi), where Z is the atomic number of the element, with a satisfactory result,though this study is only a primary one.展开更多
China still use sketch maps as control devices that guarantees consistency and accuracy of population counting in previous census.Although the rapid advancement of geospatial technologies provides many possible soluti...China still use sketch maps as control devices that guarantees consistency and accuracy of population counting in previous census.Although the rapid advancement of geospatial technologies provides many possible solutions of digital census mapping,existing researches do not answer which solution is suitable to China.Subject to many constraints originated from characteristics of China,a practical solution of census mapping based on remote sensing imagery and auxiliary geographic information was proposed and proved to be feasible through evaluation analysis and a three-stage pilot study.Imagery with 2.5 meters and higher resolution,innovative workflow of census areas delineation,easy-to-use census mapping software packages and training organization all together provide the all-around supports for the 2010 rounded census (the 6th census) mapping activities.A digital census geographic framework detailed at the level of enumeration area was established in the 2010 rounded census which fills in the gaps in the field of modern geospatial census in China.The spatially referenced digital census database,especially the detailed census units,is of great value in successive census,sampling survey and many other census-related fields.Future work including quality evaluation of census areas,census mapping solution in the Tibet Autonomous Region are also discussed.展开更多
基金Project supported by the Science and Technology Project Foundation of Guangzhou (No. 2005Z3-D0551)the Science and Technology Project Foundation of Guangzhou Education Bureau (No. 62026)
文摘Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-temporal Landsat TM and Landsat ETM+ data were employed to identify patterns of LUCC as well as to quantify urban expansion and the associated decrease of vegetation cover. The thermal infrared bands of the data were used to retrieve LST. The results revealed a strong and uneven urban growth,which caused LST to raise 4.56℃in the newly urbanized part of the study area. Overall, remote sensing and GIS technologies were effective approaches for monitoring and analyzing urban growth patterns and evaluating their impacts on LST.
文摘Element contents of tree rings and soils near tree roots collected from Deodar cedar (Cedrus deodara (Roxb.) G. Don) and Masson pine (Picks massoniana lamb.) were determined to study the relationship between the angular distribution of element contents in tree rings and the environmental information. The chemical composition and properties of soils are very much complicated, which leads to the non-uniform distribution of the element contents in tree rings. The statistical multi-variable regression method was used to got the information of the tree-centered distribution of element contents in the environment (soil) (C’), C’(z, θj ), from the distribution of element contents in tree rings (C), C(Z, θi), which depends on the plane azimuth angle (θi), i. e., C=C(Z,θi), where Z is the atomic number of the element, with a satisfactory result,though this study is only a primary one.
基金Under the auspices of National High Technology Research and Development Program of China(No.2006AA120105)National Natural Science Foundation of China(No.41001314)+1 种基金Youth Science Funds of State Key Laboratory of Resources and En-vironmental Information System(No.KA11040101)Chinese Academy of Sciences and National Science&Technology Pillar Pro-gram(No.2012BAI32B07)
文摘China still use sketch maps as control devices that guarantees consistency and accuracy of population counting in previous census.Although the rapid advancement of geospatial technologies provides many possible solutions of digital census mapping,existing researches do not answer which solution is suitable to China.Subject to many constraints originated from characteristics of China,a practical solution of census mapping based on remote sensing imagery and auxiliary geographic information was proposed and proved to be feasible through evaluation analysis and a three-stage pilot study.Imagery with 2.5 meters and higher resolution,innovative workflow of census areas delineation,easy-to-use census mapping software packages and training organization all together provide the all-around supports for the 2010 rounded census (the 6th census) mapping activities.A digital census geographic framework detailed at the level of enumeration area was established in the 2010 rounded census which fills in the gaps in the field of modern geospatial census in China.The spatially referenced digital census database,especially the detailed census units,is of great value in successive census,sampling survey and many other census-related fields.Future work including quality evaluation of census areas,census mapping solution in the Tibet Autonomous Region are also discussed.
