Availability of digital elevation models (DEMs) of a high quality is becoming more and more important in spatial studies. Standard methods for DEM creation use only intentionally acquired data sources. Two approache...Availability of digital elevation models (DEMs) of a high quality is becoming more and more important in spatial studies. Standard methods for DEM creation use only intentionally acquired data sources. Two approaches which employ various types of data sets for DEM production are proposed: (1) Method of weighted sum of different data sources with morphological enhancement that conflates any additional data sources to principal DEM, and (2) DEM updating methods of modeling absolute and relative temporal changes, considering landslides, earthquakes, quarries, watererosion, building and highway constructions, etc. Spatial modeling of environmental variables concerning both approaches for (a) quality control of data sources, considering regions, (b) pre-processing of data sources, and (c) processing of the final DEM, have been applied. The variables are called rate of karst, morphologic roughness (modeled from slope, profile curvature and elevation), characteristic features, rate of forestation, hydrological network, and rate of urbanization. Only the variables evidenced as significant were used in spatial modeling to generate homogeneous regions in spatial modeling a-c. The production process uses different regions to define high quality conflation of data sources to the final DEM. The methodology had been confirmed by case studies. The result is an overall high quality DEM with various well-known parameters.展开更多
Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. ...Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.展开更多
Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. Th...Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands.展开更多
Our original ecological diatom mud qualities as a starting point for research, analyzes people’s consumption concept, aesthetics, environmental protection awareness. This article describes the basics and the origin o...Our original ecological diatom mud qualities as a starting point for research, analyzes people’s consumption concept, aesthetics, environmental protection awareness. This article describes the basics and the origin of diatom mud, diatom mud analyzes the features, functions and defects, the diatom mud paint and wallpaper were compared to explain the process and the market situation diatom mud, silicon Prospects algae mud were discussed. Through analysis of this environmentally friendly decorative paint diatom mud, summed diatom mud there are some problems in the conventional construction; through research and exploration of the diatom mud module series is proposed in the form of modules forming diatom mud can serialization assembly decorative product design concept.展开更多
A closed-loop subspace identification method is proposed for industrial systems subject to noisy input-output observations, known as the error-in-variables (EIV) problem. Using the orthogonal projection approach to el...A closed-loop subspace identification method is proposed for industrial systems subject to noisy input-output observations, known as the error-in-variables (EIV) problem. Using the orthogonal projection approach to eliminate the noise influence, consistent estimation is guaranteed for the deterministic part of such a system. A strict proof is given for analyzing the rank condition for such orthogonal projection, in order to use the principal component analysis (PCA) based singular value decomposition (SVD) to derive the extended observability matrix and lower triangular Toeliptz matrix of the plant state-space model. In the result, the plant state matrices can be retrieved in a transparent manner from the above matrices. An illustrative example is shown to demonstrate the effectiveness and merits of the proposed subspace identification method.展开更多
The research studied the influences of high temperature, high pressure, high humidity, noise and other harmful factors in mining conditions on the people health and safety, and investigated the impacts of confined env...The research studied the influences of high temperature, high pressure, high humidity, noise and other harmful factors in mining conditions on the people health and safety, and investigated the impacts of confined environmental on human physiology factors, including temperature, humidity, noise, pressure,toxic and harmful gases in terms of environmental characteristics in underground mines and an artificial intelligence system for simulation of the environment in a confined space of deep mines. Our results show that the systolic pressure, diastolic pressure, mean pressure, heart rate, respiratory rate, typing test speed and memory level percentage are negatively correlated with temperature value, and positively correlated with humidity value; the human temperature and weight are positively correlated with temperature value, and negatively correlated with humidity value. This research lays the foundation for the study of interaction between the deep confined space environment and safety behavior.展开更多
Regional climatic conditions should be considered while designing urban development plans, with special attention to the impact of snowfall on public spaces in cities with harsh winters. The Kitami-city-hall-renewal p...Regional climatic conditions should be considered while designing urban development plans, with special attention to the impact of snowfall on public spaces in cities with harsh winters. The Kitami-city-hall-renewal project in Hokkaido, Japan was studied as an environmental assessment of snow drifting. Assessments of the two site plans proposed during the architectural planning process (A-type and B-type) were conducted in terms of the following three items: (1) The two site plans indicate snow-drifting problems around the main entrance; (2) More number of local snowdrifts on the main-street sidewalks were suggested in the B-type design; (3) Less number of snowdrifts in the parking area beside the railroad were indicated in the A-type design. These results were reflected in the architectural planning process. On the basis of this study, a desirable design process incorporating environmental assessments has been identified for cities with harsh winters.展开更多
In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumst...In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumstances and motivations. Continuous redevelopments and spatial changes can be found dispersedly in areas. Once the spatial change in a certain site occurred in an area as a building, it will be contained in the built environment of the residential area which is defined by residents, planners and designers who will take part in the following spatial changes. In Tokyo, public transportation facilities are well developed, and residents' daily life involves activities such as a slow walking and bicycle, etc. around the place of residence near the public transportation hubs, each living territories are formed in this kind of manner. Considering the maintenance of spatial value in residential areas while understanding transformation of visual local environment in residential areas which focuses on appearance of each spatial change in an area of street will be of significant importance. In this paper, the authors try to describe interactions of spatial changes in existing urban residential areas focusing on utility of players who might take part in the following spatial changes and the method of discrete choice model.展开更多
The different spatial distributions of aerosol-induced direct radiative forcing and climatic effects in a weak (2003) and a strong (2006) East Asian summer monsoon (EASM) circulation were simulated using a high-...The different spatial distributions of aerosol-induced direct radiative forcing and climatic effects in a weak (2003) and a strong (2006) East Asian summer monsoon (EASM) circulation were simulated using a high-resolution regional climate model (RegCM3).Results showed that the atmospheric circulations of summer monsoon have direct relations with transport of aerosols and their climatic effects.Both the top-of-the-atmosphere (TOA) and the surface-negative radiative forcing of aerosols were stronger in weak EASM circulations.The main difference in aerosol-induced negative forcing in two summers varied between 2 and 14 W m-2 from the Sichuan Basin to North China,where a maximum in aerosol-induced negative forcing was also noticed in the EASM-dominated areas.The spatial difference in the simulated aerosol optical depth (AOD) in two summers generally showed the similar pictures.Surface cooling effects induced by aerosols were spatially more uniform in weak EASM circulations and cooler by about 1-4.5℃.A preliminary analysis here indicated that a weaker low-level wind speed not conducive to the transport and diffusion of aerosols could make more contributions to the differences in the two circulations.展开更多
On board processing(OBP) satellite systems have obtained more and more attentions in recent years because of their high efficiency and performance.However,the OBP transponders are very sensitive to the high energy par...On board processing(OBP) satellite systems have obtained more and more attentions in recent years because of their high efficiency and performance.However,the OBP transponders are very sensitive to the high energy particles in the space radiation environments.Single event upset(SEU)is one of the major radiation effects,which influences the satellite reliability greatly.Triple modular redundancy(TMR) is a classic and efficient method to mask SEUs.However,TMR uses three identical modules and a comparison logic,the circuit size becomes unacceptable,especially in the resource limited environments such as OBP systems.Considering that,a new SEU-tolerant method based on residue code and high-level synthesis(HLS) is proposed,and the new method is applied to FIR filters,which are typical structures in the OBP systems.The simulation results show that,for an applicable HLS scheduling scheme,area reduction can be reduced by 48.26%compared to TMR,while fault missing rate is 0.15%.展开更多
Long-term evolution of the Black Sea dynamics (1980-2020) is reconstructed by means of numerical simulation. The model of the Black Sea circulation is z-coordinate model with 4.8 km horizontal space resolution and 4...Long-term evolution of the Black Sea dynamics (1980-2020) is reconstructed by means of numerical simulation. The model of the Black Sea circulation is z-coordinate model with 4.8 km horizontal space resolution and 40 levels in vertical direction. Mixing processes in the upper layer are parameterized with the Mellor-Yamada turbulent model. As for the boundary conditions on the sea surface, we used atmospheric forcing functions for the Black Sea region provided by CMCC using regional climate model COSMO-CLM. These data have a spatial resolution of 14km and a daily temporal resolution. To evaluate the quality of the Black Sea circulation dynamics, derived from simulation, the modeling results are compared with results of the Black Sea physical reanalysis. This reanalysis was performed by assimilating the temperature and salinity profiles from hydrographic surveys conducted during 1971-1993.展开更多
Presented a study on the design and implementation of spatial data modelingand application in the spatial data organization and management of a coalfield geologicalenvironment database.Based on analysis of a number of...Presented a study on the design and implementation of spatial data modelingand application in the spatial data organization and management of a coalfield geologicalenvironment database.Based on analysis of a number of existing data models and takinginto account the unique data structure and characteristic, methodology and key techniquesin the object-oriented spatial data modeling were proposed for the coalfield geological environment.The model building process was developed using object-oriented technologyand the Unified Modeling Language (UML) on the platform of ESRI geodatabase datamodels.A case study of spatial data modeling in UML was presented with successful implementationin the spatial database of the coalfield geological environment.The modelbuilding and implementation provided an effective way of representing the complexity andspecificity of coalfield geological environment spatial data and an integrated managementof spatial and property data.展开更多
Forests have long life cycles of up to several hundred years and longer.They also have very different growth rates at different stages of their life cycles.Therefore the carbon cycle in forest ecosystems has long time...Forests have long life cycles of up to several hundred years and longer.They also have very different growth rates at different stages of their life cycles.Therefore the carbon cycle in forest ecosystems has long time scales,making it necessary to consider forest age in estimating the spatiotemporal dynamics of carbon sinks in forests.The focus of this article is to review methods for combining recent remote sensing data with historical climate data for estimating the forest carbon source and sink distribution.Satellite remote sensing provides useful data for the land surface in recent decades. The information derived from remote sensing data can be used for short-term forest growth estimation and for mapping forest stand age for longterm simulations.For short-term forest growth estimation, remote sensing can provide forest structural parameters as inputs to process-based models,including big-leaf,two-leaf,and multi-layered models. These models use different strategies to upscale from leaf to canopy,and their reliability and suitability for remote sensing applications will be examined here.For long-term forest carbon cycle estimation, the spatial distribution of the forest growth rate(net primary productivity,NPP) modeled using remote sensing data in recent years is a critical input.This input can be combined with a forest age map to simulate the historical variation of NPP under the influence of climate and atmospheric changes. Another important component of the forest carbon cycle is heterotrophic respiration in the soil,which depends on the sizes of soil carbon pools as well as climate conditions.Methods for estimating the soil carbon spatial distribution and its separation into pools are described.The emphasis is placed on how to derive the soil carbon pools from NPP estimation in current years with consideration of forest carbon dynamics associated with stand age variation and climate and atmospheric changes.The role of disturbance in the forest carbon cycle and the effects of forest regrowth after disturbance are also considered in this review.An example of national forest carbon budget estimation in Canada is given at the end.It illustrates the importance of forest stand age structure in estimating the national forest carbon budgets and the effects of climate and atmospheric changes on the forest carbon cycle.展开更多
A database of Antarctic 10 m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital...A database of Antarctic 10 m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital elevation model and the main ice divide were used to delineate main drainage sectors across Antarctica. In each drainage sector, a quantitative relationship between temperature and latitude, longitude and altitude was established using available tim temperature data. Quantitative relationships incorporating other factors affecting Antarctic air temperature such as atmospheric circulation and small-scale to- pography were used to derive a 10-km resolution grid map of surface temperature. The resulting temperature patterns presented a reasonable depiction of both large and small-scale variations in Antarctic 10 m firn temperature. This map is useful for many spatial variation studies, Antarctic ice sheet models, and comparison with satellite-derived temperature data and outputs of atmospheric general circulation models.展开更多
文摘Availability of digital elevation models (DEMs) of a high quality is becoming more and more important in spatial studies. Standard methods for DEM creation use only intentionally acquired data sources. Two approaches which employ various types of data sets for DEM production are proposed: (1) Method of weighted sum of different data sources with morphological enhancement that conflates any additional data sources to principal DEM, and (2) DEM updating methods of modeling absolute and relative temporal changes, considering landslides, earthquakes, quarries, watererosion, building and highway constructions, etc. Spatial modeling of environmental variables concerning both approaches for (a) quality control of data sources, considering regions, (b) pre-processing of data sources, and (c) processing of the final DEM, have been applied. The variables are called rate of karst, morphologic roughness (modeled from slope, profile curvature and elevation), characteristic features, rate of forestation, hydrological network, and rate of urbanization. Only the variables evidenced as significant were used in spatial modeling to generate homogeneous regions in spatial modeling a-c. The production process uses different regions to define high quality conflation of data sources to the final DEM. The methodology had been confirmed by case studies. The result is an overall high quality DEM with various well-known parameters.
基金funded by Studienstiftung des deutschen VolkesGerman Research Foundation for funding(DFG,SCHI 436/14-1,BO 1333/4-1,SCHO 739/14-1)
文摘Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.
文摘Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands.
文摘Our original ecological diatom mud qualities as a starting point for research, analyzes people’s consumption concept, aesthetics, environmental protection awareness. This article describes the basics and the origin of diatom mud, diatom mud analyzes the features, functions and defects, the diatom mud paint and wallpaper were compared to explain the process and the market situation diatom mud, silicon Prospects algae mud were discussed. Through analysis of this environmentally friendly decorative paint diatom mud, summed diatom mud there are some problems in the conventional construction; through research and exploration of the diatom mud module series is proposed in the form of modules forming diatom mud can serialization assembly decorative product design concept.
基金Supported in part by Chinese Recruitment Program of Global Young Expert,Alexander von Humboldt Research Fellowship of Germany,the Foundamental Research Funds for the Central Universitiesthe National Natural Science Foundation of China (61074020)
文摘A closed-loop subspace identification method is proposed for industrial systems subject to noisy input-output observations, known as the error-in-variables (EIV) problem. Using the orthogonal projection approach to eliminate the noise influence, consistent estimation is guaranteed for the deterministic part of such a system. A strict proof is given for analyzing the rank condition for such orthogonal projection, in order to use the principal component analysis (PCA) based singular value decomposition (SVD) to derive the extended observability matrix and lower triangular Toeliptz matrix of the plant state-space model. In the result, the plant state matrices can be retrieved in a transparent manner from the above matrices. An illustrative example is shown to demonstrate the effectiveness and merits of the proposed subspace identification method.
基金funded by ‘‘a group of four’’ Safety Science and Technology Project of State Production Safety Supervision Administration of China (No. 20130801)
文摘The research studied the influences of high temperature, high pressure, high humidity, noise and other harmful factors in mining conditions on the people health and safety, and investigated the impacts of confined environmental on human physiology factors, including temperature, humidity, noise, pressure,toxic and harmful gases in terms of environmental characteristics in underground mines and an artificial intelligence system for simulation of the environment in a confined space of deep mines. Our results show that the systolic pressure, diastolic pressure, mean pressure, heart rate, respiratory rate, typing test speed and memory level percentage are negatively correlated with temperature value, and positively correlated with humidity value; the human temperature and weight are positively correlated with temperature value, and negatively correlated with humidity value. This research lays the foundation for the study of interaction between the deep confined space environment and safety behavior.
文摘Regional climatic conditions should be considered while designing urban development plans, with special attention to the impact of snowfall on public spaces in cities with harsh winters. The Kitami-city-hall-renewal project in Hokkaido, Japan was studied as an environmental assessment of snow drifting. Assessments of the two site plans proposed during the architectural planning process (A-type and B-type) were conducted in terms of the following three items: (1) The two site plans indicate snow-drifting problems around the main entrance; (2) More number of local snowdrifts on the main-street sidewalks were suggested in the B-type design; (3) Less number of snowdrifts in the parking area beside the railroad were indicated in the A-type design. These results were reflected in the architectural planning process. On the basis of this study, a desirable design process incorporating environmental assessments has been identified for cities with harsh winters.
文摘In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumstances and motivations. Continuous redevelopments and spatial changes can be found dispersedly in areas. Once the spatial change in a certain site occurred in an area as a building, it will be contained in the built environment of the residential area which is defined by residents, planners and designers who will take part in the following spatial changes. In Tokyo, public transportation facilities are well developed, and residents' daily life involves activities such as a slow walking and bicycle, etc. around the place of residence near the public transportation hubs, each living territories are formed in this kind of manner. Considering the maintenance of spatial value in residential areas while understanding transformation of visual local environment in residential areas which focuses on appearance of each spatial change in an area of street will be of significant importance. In this paper, the authors try to describe interactions of spatial changes in existing urban residential areas focusing on utility of players who might take part in the following spatial changes and the method of discrete choice model.
基金supported by the National Basic Research Program of China (2009CB421407)the Special Public Welfare Research Fund for Meteorological Profession of China Meteorological Administration (GYHY201006022)
文摘The different spatial distributions of aerosol-induced direct radiative forcing and climatic effects in a weak (2003) and a strong (2006) East Asian summer monsoon (EASM) circulation were simulated using a high-resolution regional climate model (RegCM3).Results showed that the atmospheric circulations of summer monsoon have direct relations with transport of aerosols and their climatic effects.Both the top-of-the-atmosphere (TOA) and the surface-negative radiative forcing of aerosols were stronger in weak EASM circulations.The main difference in aerosol-induced negative forcing in two summers varied between 2 and 14 W m-2 from the Sichuan Basin to North China,where a maximum in aerosol-induced negative forcing was also noticed in the EASM-dominated areas.The spatial difference in the simulated aerosol optical depth (AOD) in two summers generally showed the similar pictures.Surface cooling effects induced by aerosols were spatially more uniform in weak EASM circulations and cooler by about 1-4.5℃.A preliminary analysis here indicated that a weaker low-level wind speed not conducive to the transport and diffusion of aerosols could make more contributions to the differences in the two circulations.
基金Supported by the National S&T Major Project(No.2011ZX03003-003-01,2011ZX03004-004)the National Basic Research Program of China(No.2012CB316002)
文摘On board processing(OBP) satellite systems have obtained more and more attentions in recent years because of their high efficiency and performance.However,the OBP transponders are very sensitive to the high energy particles in the space radiation environments.Single event upset(SEU)is one of the major radiation effects,which influences the satellite reliability greatly.Triple modular redundancy(TMR) is a classic and efficient method to mask SEUs.However,TMR uses three identical modules and a comparison logic,the circuit size becomes unacceptable,especially in the resource limited environments such as OBP systems.Considering that,a new SEU-tolerant method based on residue code and high-level synthesis(HLS) is proposed,and the new method is applied to FIR filters,which are typical structures in the OBP systems.The simulation results show that,for an applicable HLS scheduling scheme,area reduction can be reduced by 48.26%compared to TMR,while fault missing rate is 0.15%.
文摘Long-term evolution of the Black Sea dynamics (1980-2020) is reconstructed by means of numerical simulation. The model of the Black Sea circulation is z-coordinate model with 4.8 km horizontal space resolution and 40 levels in vertical direction. Mixing processes in the upper layer are parameterized with the Mellor-Yamada turbulent model. As for the boundary conditions on the sea surface, we used atmospheric forcing functions for the Black Sea region provided by CMCC using regional climate model COSMO-CLM. These data have a spatial resolution of 14km and a daily temporal resolution. To evaluate the quality of the Black Sea circulation dynamics, derived from simulation, the modeling results are compared with results of the Black Sea physical reanalysis. This reanalysis was performed by assimilating the temperature and salinity profiles from hydrographic surveys conducted during 1971-1993.
基金Supported by the Natural Science Foundation of Shanxi Province(2008011028-2)
文摘Presented a study on the design and implementation of spatial data modelingand application in the spatial data organization and management of a coalfield geologicalenvironment database.Based on analysis of a number of existing data models and takinginto account the unique data structure and characteristic, methodology and key techniquesin the object-oriented spatial data modeling were proposed for the coalfield geological environment.The model building process was developed using object-oriented technologyand the Unified Modeling Language (UML) on the platform of ESRI geodatabase datamodels.A case study of spatial data modeling in UML was presented with successful implementationin the spatial database of the coalfield geological environment.The modelbuilding and implementation provided an effective way of representing the complexity andspecificity of coalfield geological environment spatial data and an integrated managementof spatial and property data.
文摘Forests have long life cycles of up to several hundred years and longer.They also have very different growth rates at different stages of their life cycles.Therefore the carbon cycle in forest ecosystems has long time scales,making it necessary to consider forest age in estimating the spatiotemporal dynamics of carbon sinks in forests.The focus of this article is to review methods for combining recent remote sensing data with historical climate data for estimating the forest carbon source and sink distribution.Satellite remote sensing provides useful data for the land surface in recent decades. The information derived from remote sensing data can be used for short-term forest growth estimation and for mapping forest stand age for longterm simulations.For short-term forest growth estimation, remote sensing can provide forest structural parameters as inputs to process-based models,including big-leaf,two-leaf,and multi-layered models. These models use different strategies to upscale from leaf to canopy,and their reliability and suitability for remote sensing applications will be examined here.For long-term forest carbon cycle estimation, the spatial distribution of the forest growth rate(net primary productivity,NPP) modeled using remote sensing data in recent years is a critical input.This input can be combined with a forest age map to simulate the historical variation of NPP under the influence of climate and atmospheric changes. Another important component of the forest carbon cycle is heterotrophic respiration in the soil,which depends on the sizes of soil carbon pools as well as climate conditions.Methods for estimating the soil carbon spatial distribution and its separation into pools are described.The emphasis is placed on how to derive the soil carbon pools from NPP estimation in current years with consideration of forest carbon dynamics associated with stand age variation and climate and atmospheric changes.The role of disturbance in the forest carbon cycle and the effects of forest regrowth after disturbance are also considered in this review.An example of national forest carbon budget estimation in Canada is given at the end.It illustrates the importance of forest stand age structure in estimating the national forest carbon budgets and the effects of climate and atmospheric changes on the forest carbon cycle.
基金supported by National Natural Science Foundation of China (Grant No. 40825017)Chinese Academy of Sciences (Grant No. SKLCSZZ-2008-06)National Key Technology R & D Program (Grant No. 2006BAB18B01)
文摘A database of Antarctic 10 m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital elevation model and the main ice divide were used to delineate main drainage sectors across Antarctica. In each drainage sector, a quantitative relationship between temperature and latitude, longitude and altitude was established using available tim temperature data. Quantitative relationships incorporating other factors affecting Antarctic air temperature such as atmospheric circulation and small-scale to- pography were used to derive a 10-km resolution grid map of surface temperature. The resulting temperature patterns presented a reasonable depiction of both large and small-scale variations in Antarctic 10 m firn temperature. This map is useful for many spatial variation studies, Antarctic ice sheet models, and comparison with satellite-derived temperature data and outputs of atmospheric general circulation models.