Maximum light use efficiency (εmax) is a key parameter for the estimation of net primary pro-ductivity (NPP) derived from remote sensing data. There are still many divergences about its value for each vegetation type...Maximum light use efficiency (εmax) is a key parameter for the estimation of net primary pro-ductivity (NPP) derived from remote sensing data. There are still many divergences about its value for each vegetation type. The εmax for some typical vegetation types in China is simulated using a modi-fied least squares function based on NOAA/AVHRR remote sensing data and field-observed NPP data. The vegetation classification accuracy is introduced to the process. The sensitivity analysis of εmax to vegetation classification accuracy is also conducted. The results show that the simulated values of εmax are greater than the value used in CASA model, and less than the values simulated with BIOME-BGC model. This is consistent with some other studies. The rela-tive error of εmax resulting from classification accuracy is ?5.5%―8.0%. This indicates that the simulated values of εmax are reliable and stable.展开更多
The biosphere of the Earth is essential to human survival and development.The services of ecosystems are critical to the functioning of the Earth’s life-support system.They contribute to human welfare both directly a...The biosphere of the Earth is essential to human survival and development.The services of ecosystems are critical to the functioning of the Earth’s life-support system.They contribute to human welfare both directly and indirectly.Ecological capital refers to the sum of the direct biological resources value and the indirect ecosystem services value.It is necessary to estimate the ecological capital in order to bring it to the society and market economic system,and draw the social attention to ecological environment constructions.An estimation model for eco-logical capital based on remote sensing is presented in this paper.The parameters in the model are quantitatively measured using NOAA/AVHRR and other ancillary data,including the land cover types,the vegetation coverage,and the vegetation net primary productivity(NPP)of ter-restrial ecosystem.Based on the economic parameters in previously published studies and a few original calculations,the annual ecological capital of the entire terrestrial ecosystem of China is quantitatively estimated at 6.44 trillion(10^(12))yuan(RMB),and the spatial distribution of the eco-logical capital is also analyzed.Traditional ecological methods to ecological capital measurement are based on homogeneous plot scales,and the regional scaling is a key problem in their appli-cations.As the proposed remote sensing approach,it provides a new method to ecological capital measurement completely based on observation data.It can not only overcome the re-gional scaling problem easily,but also allows the ecological capital to be estimated objectively and spatial-explicitly.展开更多
文摘Maximum light use efficiency (εmax) is a key parameter for the estimation of net primary pro-ductivity (NPP) derived from remote sensing data. There are still many divergences about its value for each vegetation type. The εmax for some typical vegetation types in China is simulated using a modi-fied least squares function based on NOAA/AVHRR remote sensing data and field-observed NPP data. The vegetation classification accuracy is introduced to the process. The sensitivity analysis of εmax to vegetation classification accuracy is also conducted. The results show that the simulated values of εmax are greater than the value used in CASA model, and less than the values simulated with BIOME-BGC model. This is consistent with some other studies. The rela-tive error of εmax resulting from classification accuracy is ?5.5%―8.0%. This indicates that the simulated values of εmax are reliable and stable.
基金the National Key Bas ic Research&Deve lopment Program(Grant No.G2000018604)the National High TechnologyResearch and Development Program of China(Grant No.2002AA133060).
文摘The biosphere of the Earth is essential to human survival and development.The services of ecosystems are critical to the functioning of the Earth’s life-support system.They contribute to human welfare both directly and indirectly.Ecological capital refers to the sum of the direct biological resources value and the indirect ecosystem services value.It is necessary to estimate the ecological capital in order to bring it to the society and market economic system,and draw the social attention to ecological environment constructions.An estimation model for eco-logical capital based on remote sensing is presented in this paper.The parameters in the model are quantitatively measured using NOAA/AVHRR and other ancillary data,including the land cover types,the vegetation coverage,and the vegetation net primary productivity(NPP)of ter-restrial ecosystem.Based on the economic parameters in previously published studies and a few original calculations,the annual ecological capital of the entire terrestrial ecosystem of China is quantitatively estimated at 6.44 trillion(10^(12))yuan(RMB),and the spatial distribution of the eco-logical capital is also analyzed.Traditional ecological methods to ecological capital measurement are based on homogeneous plot scales,and the regional scaling is a key problem in their appli-cations.As the proposed remote sensing approach,it provides a new method to ecological capital measurement completely based on observation data.It can not only overcome the re-gional scaling problem easily,but also allows the ecological capital to be estimated objectively and spatial-explicitly.
