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 land use change data obtained from the interpretation of remote sensing images in 1985, 1995, 2005 and 2008, the research applied principal component analysis, Markov chain and ESDA method, and took culti...Based on the land use change data obtained from the interpretation of remote sensing images in 1985, 1995, 2005 and 2008, the research applied principal component analysis, Markov chain and ESDA method, and took cultivated land patch as the basic unit of landscape. A comprehensive measure of the fragmentation of cultivated land was made in Jiangsu counties and its temporal and spatial evolution characteristics and driving process from the perspective of landscape ecology were discussed. The results are as follows:(1)The overall fragmentation of cultivated land in Jiangsu Province presents that the eastern coastal areas are low, the interior of the west is high, the fragmentation of northern and southern Jiangsu is high, while the fragmentation of mid-Jiangsu is low.(2)The degree of fragmentation of cultivated land in most area of southern Jiangsu and midJiangsu showed an upward trend, while the fragmentation of cultivated land in northern Jiangsu showed a downward trend from 1985 to 2008. The degree of agglomeration of cultivated land is weakened continuously, the area of high value agglomeration is decreasing and the trend of "polarization" is weakening.(3) Topographic condition is the decisive factor for the formation of the difference pattern. The change of rural residential land, cultivated land and the scale of urban land use plays a role on the cultivated land fragmentation index, among them, the change of rural residential land scale has the most significant effect on cultivated land fragmentation.展开更多
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.
基金Supported by National Natural Science Foundation of China(41301651,41401629)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Based on the land use change data obtained from the interpretation of remote sensing images in 1985, 1995, 2005 and 2008, the research applied principal component analysis, Markov chain and ESDA method, and took cultivated land patch as the basic unit of landscape. A comprehensive measure of the fragmentation of cultivated land was made in Jiangsu counties and its temporal and spatial evolution characteristics and driving process from the perspective of landscape ecology were discussed. The results are as follows:(1)The overall fragmentation of cultivated land in Jiangsu Province presents that the eastern coastal areas are low, the interior of the west is high, the fragmentation of northern and southern Jiangsu is high, while the fragmentation of mid-Jiangsu is low.(2)The degree of fragmentation of cultivated land in most area of southern Jiangsu and midJiangsu showed an upward trend, while the fragmentation of cultivated land in northern Jiangsu showed a downward trend from 1985 to 2008. The degree of agglomeration of cultivated land is weakened continuously, the area of high value agglomeration is decreasing and the trend of "polarization" is weakening.(3) Topographic condition is the decisive factor for the formation of the difference pattern. The change of rural residential land, cultivated land and the scale of urban land use plays a role on the cultivated land fragmentation index, among them, the change of rural residential land scale has the most significant effect on cultivated land fragmentation.
