The value of application of three-dimensional visualization and animation technique in dynamic simulation of geographical landscape formation is analyzed and, in particular, how to simulate the formation and evolvemen...The value of application of three-dimensional visualization and animation technique in dynamic simulation of geographical landscape formation is analyzed and, in particular, how to simulate the formation and evolvement of geographical landscape in temporal dimension is discussed thoroughly. Based on various modeling tools in 3DS MAX and original DEM data of the study area acquired from topographic map, real three-dimensional terrain model is generated by using the method of three-dimensional mesh approximation through DEM interpolating and surface modeling, which leads to the realization of the dynamic visualization and simulation of volcanic landscape, formation and evolvement. Furthermore, the dynamic three-dimensional visual virtual scenery of the formation and evolvement of the volcano in the Changbai Mountains of Jilin, China, is constructed. The applicability, potential, and corresponding technique of using 3DS MAX to dynamically simulate the formation of geographical landscape are expatiated.展开更多
As a result of environmental degradation,urban green space has become a key issue for urban sustainable development.This paper takes Liaoyang City in Northeast China as an example to develop green space planning using...As a result of environmental degradation,urban green space has become a key issue for urban sustainable development.This paper takes Liaoyang City in Northeast China as an example to develop green space planning using the computational fluid dynamics (CFD) model,landscape ecological principles and Geographical Information System (GIS).Based on the influencing factors of topography,building density and orientation,Shou Mountain,Longding Mountain and the Taizi River were selected as the urban ventilation paths to promote wind and oxygen circulation.Oxygen concentration around the green spaces gradually decreased with wind speed increase and wind direction change.There were obvious negative correlation relationships between the oxygen dispersion concentration and urban layout factors such as the building plot ratio and building density.Comparison with the field measurements found that there was significant correlation relationship between simulated oxygen concentration and field measurements (R 2=0.6415,p<0.001),moreover,simulation precision was higher than 92%,which indicated CFD model was effective for urban oxygen concentration simulation.Only less than 10% areas in Liaoyang City proper needed more green space urgently to improve oxygen concentration,mainly concentrated in Baitai and west Wensheng districts.Based on land-scape ecology principle,green space planning at different spatial scales were proposed to create a green space network system for Liaoyang City,including features such as green wedges,green belts and parks.Totally,about 2012 ha of green space need to be constructed as oxygen sources and ventilation paths.Compared with the current green space pattern,proposed green space planning could improve oxygen concentration obviously.The CFD model and research results in this paper could provide an effective way and theory support for sustainable development of urban green space.展开更多
Based on the theories of landscape ecology, landscape eco environment in the control watershed by reservoir of Erlong Mountain in Heilongjiang Province was analyzed and assessed by using GIS technique and statistical ...Based on the theories of landscape ecology, landscape eco environment in the control watershed by reservoir of Erlong Mountain in Heilongjiang Province was analyzed and assessed by using GIS technique and statistical model of Principal Component Analysis and Spatial Cluster Analysis. It is found that 100.08km2(36%)of the total area is in the state of kilter,85.73km2(31%)of the total area is in the state of general,and 47.26km2(17%)and 15.48km2(16%)is in the relatively poor state and ideal state. According to landscape ecological structure,there are three landscape function areas being planned and designed. 1) Agricultural landscape function area: its developmental direction is tour agriculture and high benefit agriculture. 2) Eco environment protected function area:the direction of development and utilization of this region is to develop vigorously forest for soil and water conservation, and try to increase the rate of vegetation cover. 3) Forest landscape function area: rational cut and utilization of forest resources, space optimization disposal of category of forest, foster of forest and protection of wildwood will become the main development directions for this region. This study trys to provide scientific foundation for ecological restoration of the whole valley and its sustainable development.展开更多
The Chinese yew（Taxus wallichiana）,which is widely distributed in the Himalayas and in southern China,is now on the edge of extinction.In order to understand the evolutionary processes that control the current diver...The Chinese yew（Taxus wallichiana）,which is widely distributed in the Himalayas and in southern China,is now on the edge of extinction.In order to understand the evolutionary processes that control the current diversity within this species at the genetic and ecological levels,its genetic patterns and range dynamics must first be identified and mapped.This knowledge can then be applied in the development of an effective conservation strategy.Based on molecular data obtained from 48 populations of T.wallichiana,we used GIS-based interpolation approach for the explicit visualization of patterns of genetic divergence and diversity,and a number of potential evolutionary hotspots have been specifically identified within the genetic landscape maps.Within the maps of genetic divergence and diversity,five areas of high inter-population genetic divergence and six areas of high intra-population genetic diversity have been highlighted in a number of separate mountain regions,and these evolutionary hotspots should have the priority to be protected.Furthermore,four geographical barriers have been identified： the eastern Himalayas,the Yunnan Plateau,the Hengduan Mountains and the Taiwan Strait.According to ecological niche modeling（ENM）,the populations of T.wallichiana within the Sino-Himalayan Forest floristic subkingdom experienced westward expansion from the periods of Last Inter-glacial to Last Glacial Maximum（LGM）.Following the LGM,the distribution range overall became reduced and fragmented.These findings challenge the classic mode of contraction-expansion in response to the last glaciation.In conclusion,our findings suggest that the changes in geographical landscapes and climate that occurred during the Quaternary resulted in current genetic landscape patterns.展开更多
Aims Understanding the factors that control biodiversity distributions at different spatial scales has been a key challenge for conservation efforts.That biodiversity,reflected in differences in species compositions a...Aims Understanding the factors that control biodiversity distributions at different spatial scales has been a key challenge for conservation efforts.That biodiversity,reflected in differences in species compositions among sites(beta diversity),can be derived from species replacement(turnover)and is driven by multiple factors.Here,we sought to tackle this issue through two questions related to threatened Brazilian seasonally dry forests:(i)what is the contribution of species turnover to beta diversity?and(ii)which factors drive variations in species compositions among forest patches?Methods We sampled tree species and environmental variables(soils and climate)in 17 dry forest patches spaced almost 300 km apart.We used the beta diversity partitioning framework to determine the contribution of turnover.We used redundancy analysis,with properly controlled spatial structure,to assess the contributions of the environmental and spatial factors to the variations of the species composition.Important Findings Beta diversity among the patches was mainly represented by the turnover component(98.2%),with Simpson dissimilarity superior to other regions of the country(means of 0.89 and 0.71 in multiple site and pairwise measures,respectively).The environmental factors measured explained more than space,representing 30.3%of the variation of the species composition,of which 28.1%was nonspatially structured.We suggest that 300 km represents a threshold at which edaphic and climatic predictors have similar effects in determining community turnover(14.9%and 12.6%,respectively,without spatial structure).Thus,conservation strategies should be considered across landscapes to effectively protect tropical forest diversity,as even considering the different climatic aspects covered by the scale,landscaped edaphic varieties are important drivers of species turnover.展开更多
文摘The value of application of three-dimensional visualization and animation technique in dynamic simulation of geographical landscape formation is analyzed and, in particular, how to simulate the formation and evolvement of geographical landscape in temporal dimension is discussed thoroughly. Based on various modeling tools in 3DS MAX and original DEM data of the study area acquired from topographic map, real three-dimensional terrain model is generated by using the method of three-dimensional mesh approximation through DEM interpolating and surface modeling, which leads to the realization of the dynamic visualization and simulation of volcanic landscape, formation and evolvement. Furthermore, the dynamic three-dimensional visual virtual scenery of the formation and evolvement of the volcano in the Changbai Mountains of Jilin, China, is constructed. The applicability, potential, and corresponding technique of using 3DS MAX to dynamically simulate the formation of geographical landscape are expatiated.
基金Under the auspices of National Key Technology Research and Development Program of China (No.2008BAJ10B01-01)National Natural Science Foundation of China (No.40801069)
文摘As a result of environmental degradation,urban green space has become a key issue for urban sustainable development.This paper takes Liaoyang City in Northeast China as an example to develop green space planning using the computational fluid dynamics (CFD) model,landscape ecological principles and Geographical Information System (GIS).Based on the influencing factors of topography,building density and orientation,Shou Mountain,Longding Mountain and the Taizi River were selected as the urban ventilation paths to promote wind and oxygen circulation.Oxygen concentration around the green spaces gradually decreased with wind speed increase and wind direction change.There were obvious negative correlation relationships between the oxygen dispersion concentration and urban layout factors such as the building plot ratio and building density.Comparison with the field measurements found that there was significant correlation relationship between simulated oxygen concentration and field measurements (R 2=0.6415,p<0.001),moreover,simulation precision was higher than 92%,which indicated CFD model was effective for urban oxygen concentration simulation.Only less than 10% areas in Liaoyang City proper needed more green space urgently to improve oxygen concentration,mainly concentrated in Baitai and west Wensheng districts.Based on land-scape ecology principle,green space planning at different spatial scales were proposed to create a green space network system for Liaoyang City,including features such as green wedges,green belts and parks.Totally,about 2012 ha of green space need to be constructed as oxygen sources and ventilation paths.Compared with the current green space pattern,proposed green space planning could improve oxygen concentration obviously.The CFD model and research results in this paper could provide an effective way and theory support for sustainable development of urban green space.
文摘Based on the theories of landscape ecology, landscape eco environment in the control watershed by reservoir of Erlong Mountain in Heilongjiang Province was analyzed and assessed by using GIS technique and statistical model of Principal Component Analysis and Spatial Cluster Analysis. It is found that 100.08km2(36%)of the total area is in the state of kilter,85.73km2(31%)of the total area is in the state of general,and 47.26km2(17%)and 15.48km2(16%)is in the relatively poor state and ideal state. According to landscape ecological structure,there are three landscape function areas being planned and designed. 1) Agricultural landscape function area: its developmental direction is tour agriculture and high benefit agriculture. 2) Eco environment protected function area:the direction of development and utilization of this region is to develop vigorously forest for soil and water conservation, and try to increase the rate of vegetation cover. 3) Forest landscape function area: rational cut and utilization of forest resources, space optimization disposal of category of forest, foster of forest and protection of wildwood will become the main development directions for this region. This study trys to provide scientific foundation for ecological restoration of the whole valley and its sustainable development.
基金National Basic Research Program of China(No.2010CB951704)National Natural Science Foundation of China(No.41271068)
文摘The Chinese yew（Taxus wallichiana）,which is widely distributed in the Himalayas and in southern China,is now on the edge of extinction.In order to understand the evolutionary processes that control the current diversity within this species at the genetic and ecological levels,its genetic patterns and range dynamics must first be identified and mapped.This knowledge can then be applied in the development of an effective conservation strategy.Based on molecular data obtained from 48 populations of T.wallichiana,we used GIS-based interpolation approach for the explicit visualization of patterns of genetic divergence and diversity,and a number of potential evolutionary hotspots have been specifically identified within the genetic landscape maps.Within the maps of genetic divergence and diversity,five areas of high inter-population genetic divergence and six areas of high intra-population genetic diversity have been highlighted in a number of separate mountain regions,and these evolutionary hotspots should have the priority to be protected.Furthermore,four geographical barriers have been identified： the eastern Himalayas,the Yunnan Plateau,the Hengduan Mountains and the Taiwan Strait.According to ecological niche modeling（ENM）,the populations of T.wallichiana within the Sino-Himalayan Forest floristic subkingdom experienced westward expansion from the periods of Last Inter-glacial to Last Glacial Maximum（LGM）.Following the LGM,the distribution range overall became reduced and fragmented.These findings challenge the classic mode of contraction-expansion in response to the last glaciation.In conclusion,our findings suggest that the changes in geographical landscapes and climate that occurred during the Quaternary resulted in current genetic landscape patterns.
基金This work was supported by the Fundação de Amparo à Pesquisa do Estado de Minas Gerais(FAPEMIG)[12.070/2009].
文摘Aims Understanding the factors that control biodiversity distributions at different spatial scales has been a key challenge for conservation efforts.That biodiversity,reflected in differences in species compositions among sites(beta diversity),can be derived from species replacement(turnover)and is driven by multiple factors.Here,we sought to tackle this issue through two questions related to threatened Brazilian seasonally dry forests:(i)what is the contribution of species turnover to beta diversity?and(ii)which factors drive variations in species compositions among forest patches?Methods We sampled tree species and environmental variables(soils and climate)in 17 dry forest patches spaced almost 300 km apart.We used the beta diversity partitioning framework to determine the contribution of turnover.We used redundancy analysis,with properly controlled spatial structure,to assess the contributions of the environmental and spatial factors to the variations of the species composition.Important Findings Beta diversity among the patches was mainly represented by the turnover component(98.2%),with Simpson dissimilarity superior to other regions of the country(means of 0.89 and 0.71 in multiple site and pairwise measures,respectively).The environmental factors measured explained more than space,representing 30.3%of the variation of the species composition,of which 28.1%was nonspatially structured.We suggest that 300 km represents a threshold at which edaphic and climatic predictors have similar effects in determining community turnover(14.9%and 12.6%,respectively,without spatial structure).Thus,conservation strategies should be considered across landscapes to effectively protect tropical forest diversity,as even considering the different climatic aspects covered by the scale,landscaped edaphic varieties are important drivers of species turnover.
