This study seeks to isolate a select group of landscape metrics particularly well-suited for describing the Hani Terrace in southwest of China.We examined the response of 47 landscape metrics to a large range of image...This study seeks to isolate a select group of landscape metrics particularly well-suited for describing the Hani Terrace in southwest of China.We examined the response of 47 landscape metrics to a large range of imagery grain sizes.Based on a correlation analysis,the original 47 metrics were placed into 21 groups such that all metrics within a group were strongly correlated with each other with a value of more than 0.9,and were represented by a single descriptor.Using these cross-sectional metrics in the context of principal components analysis,we found that five factors explained almost 93％ of the total variation in the landscape pattern.The highest loadings for these five factors were the Splitting index （SPLIT）,Patch area distribution （AREA_CV）,Shannon＇s diversity index （SHDI）,Euclidean nearest neighbor distance distribution （ENN_AM）,and Total core area （TCA）,respectively.Considering the real landscape,we added the Patch fractal dimension distribution （FRAC_MN） as the sixth landscape pattern metric.As the scale effect of landscape pattern metrics we design to investigate how a suite of commonly use landscape metrics respond to changing grain size.Based on the anlasis,we determined that the best domain of scale to characterise the Hani Terrace pattern metrics is between 40m and 45m.Through the fractal method,we found that the characteristic scale of the Hani Terrace is the same as the scale domain of metrics,among the 40m and 45m.We suggest that the majority of the patterns in the Hani Terrace landscapes,indeed for all those in southwest China,can be described effectively with these six metrics.展开更多
The Landsat images of the 2000,2005,2010,2015,2018 are selected as the data source to retrieve land cover and surface temperature data.The contribution of Sink-Source landscape pattern to the heat island and its ecolo...The Landsat images of the 2000,2005,2010,2015,2018 are selected as the data source to retrieve land cover and surface temperature data.The contribution of Sink-Source landscape pattern to the heat island and its ecological effects on urban and rural gradient were analyzed by using Heat Index(HI),Sink and Source Landscape Contribution(CI_(sink),CI_(source))and Landscape Effect Index(LI)in Haikou.The results show that the heat island is concentrated on the West Coast,and in the central urban and Jiangdong New Area;the HI shows a pattern of decreasing value with the following land types:“Bare land>Artificial surface﹥Source landscape>Shrub grassland>Farmland>Sink landscape>Woodland>Water body”.In the central city section,the CI_(sink) and CI_(source) are relatively large in these five periods.The LI decreases rapidly along the urban-rural gradient,promoting the Urban Heat Island(UHI)to a large degree.In contrast,the suburban area contributes to a lesser degree.Overall,the LI fluctuates,the proportion of mitigating UHI is large,and there is a second peak outside the city center.The existing Source-Sink Landscape contributes the most to UHI in the central urban area,and this contribution decreases along the urban-rural gradient.With the continuous expansion of city-town areas,the proportion of Sink areas has increased along the gradient,and the proportion of Source areas has subsequently declined,resulting in the spatial transfer and diffusion of UHI.Therefore,a UHI mitigation strategy based on the theory of regional landscape systems is proposed here.展开更多
基金National Public Benefit(Environmental) Research Foundation of China(201009020)National Natural Science Foundation of China(3120037641201580)
文摘This study seeks to isolate a select group of landscape metrics particularly well-suited for describing the Hani Terrace in southwest of China.We examined the response of 47 landscape metrics to a large range of imagery grain sizes.Based on a correlation analysis,the original 47 metrics were placed into 21 groups such that all metrics within a group were strongly correlated with each other with a value of more than 0.9,and were represented by a single descriptor.Using these cross-sectional metrics in the context of principal components analysis,we found that five factors explained almost 93％ of the total variation in the landscape pattern.The highest loadings for these five factors were the Splitting index （SPLIT）,Patch area distribution （AREA_CV）,Shannon＇s diversity index （SHDI）,Euclidean nearest neighbor distance distribution （ENN_AM）,and Total core area （TCA）,respectively.Considering the real landscape,we added the Patch fractal dimension distribution （FRAC_MN） as the sixth landscape pattern metric.As the scale effect of landscape pattern metrics we design to investigate how a suite of commonly use landscape metrics respond to changing grain size.Based on the anlasis,we determined that the best domain of scale to characterise the Hani Terrace pattern metrics is between 40m and 45m.Through the fractal method,we found that the characteristic scale of the Hani Terrace is the same as the scale domain of metrics,among the 40m and 45m.We suggest that the majority of the patterns in the Hani Terrace landscapes,indeed for all those in southwest China,can be described effectively with these six metrics.
基金The Natural Science Foundation of Hainan Province(421MS015,421QN200)The Hainan Province Philosophy and Social Science Planning Project(HNSK(ZC)21-126)。
文摘The Landsat images of the 2000,2005,2010,2015,2018 are selected as the data source to retrieve land cover and surface temperature data.The contribution of Sink-Source landscape pattern to the heat island and its ecological effects on urban and rural gradient were analyzed by using Heat Index(HI),Sink and Source Landscape Contribution(CI_(sink),CI_(source))and Landscape Effect Index(LI)in Haikou.The results show that the heat island is concentrated on the West Coast,and in the central urban and Jiangdong New Area;the HI shows a pattern of decreasing value with the following land types:“Bare land>Artificial surface﹥Source landscape>Shrub grassland>Farmland>Sink landscape>Woodland>Water body”.In the central city section,the CI_(sink) and CI_(source) are relatively large in these five periods.The LI decreases rapidly along the urban-rural gradient,promoting the Urban Heat Island(UHI)to a large degree.In contrast,the suburban area contributes to a lesser degree.Overall,the LI fluctuates,the proportion of mitigating UHI is large,and there is a second peak outside the city center.The existing Source-Sink Landscape contributes the most to UHI in the central urban area,and this contribution decreases along the urban-rural gradient.With the continuous expansion of city-town areas,the proportion of Sink areas has increased along the gradient,and the proportion of Source areas has subsequently declined,resulting in the spatial transfer and diffusion of UHI.Therefore,a UHI mitigation strategy based on the theory of regional landscape systems is proposed here.
