Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise ...Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.展开更多
By using GIS and remote sensing techniques, the paper discusses how human activities have changed along the Yellow River in Henan province, China and how these altered activities have influenced the wetland landscape ...By using GIS and remote sensing techniques, the paper discusses how human activities have changed along the Yellow River in Henan province, China and how these altered activities have influenced the wetland landscape pattern change from 1987 to 2002. Results show that the total area of the wetland reduces dramatically compared to 1987, the total area of wetland reduces by 19.18%, the number of the patches in 2002 increases by 21.17%, the density increases by 50%, and the total perimeter increases by 1,290,491 m. Disturbed by human activities, landscape diversity index decreases from 1.1740 in 1987 to 0.9803 in 2002. During the last 20 years, the total area of the rice wetland increases, while the others decrease. Among those, the area of the bulrush wetland decreases most. In 1987, it takes 0.5% of the total area, but in 2002, it only takes 0.11%. The interpenetration of human influences on the wetland natural system has been long and close. The impacts of human activities on the spatial pattern of the wetland landscape along the Yellow River in Henan from 1987 to 2002 are great.展开更多
With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators...With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators and planners to optimize the urban development areas and define the ecological protection red lines. Based on the SPOT images and field investigation data of urban green spaces within the sixth ring road of Beijing in 2000, 2005 and 2010, the study investigated the dynamic changes of urban green spaces in this area, by means of GIS techniques and landscape ecology methods. The results indicated that green spaces in Beijing have decreased by 207 km2 from 2000 to 2010 at the expense of agricultural lands and waters. Although there has been some increases in urban forests and grasslands, it cannot compensate the rapid decrease of urban green spaces. The land cover types conversion occurred mainly in the areas between the fifth and sixth ring roads while the zones encircled by the fourth ring road had a little change. In addition, landscape metrics such as number of patches(NP) and shape index(SHAPE) increased, but the mean nearest-neighbor distance(MNN), aggregation index(AI) and patch cohesion index(COHESION) decreased during the period of 2000-2010. Also green landscapes became considerably isolated and fragmented. The study disclosed the obvious changes of green space size, composition and layout in urban districts of Beijing City from 2000 to 2010, and highlighted that construction of urban green space should consider not only the geometric or aesthetic effect, but also the increase of vertical green volume and optimization of spatial layout to fully develop the ecological service functions of green spaces.展开更多
Landscape pattern analysis is becoming the core to study global or local change. Incorporated with fast, dynamic and precise spatial information technology, Landscape pattern analysis has been a foundation for the gov...Landscape pattern analysis is becoming the core to study global or local change. Incorporated with fast, dynamic and precise spatial information technology, Landscape pattern analysis has been a foundation for the governments to make decision. In this paper, Maoxian county, located in the northwest of Sichuan Province, was selected as the study area. Landsat TM data in 1994 and Landsat ETM data in 2002, with dates are just same as the time of national policy changes, are classified to make the landscape patterns change. The result indicates that, from 1994 to 2002, owing to the policies of the project of wild wood resource protect and the project of returning land for farming to forestry (grass), the forests has increased about 2.68%, Natural meadow has increased about 0.83%, Shrubby has increased about 0.63%, Farm land has decreased about 4.10% and the fragment of forests in 2002 is lower than in 1994. This states that the national policy actioned during 1990s have much positive influence on the landscape patterns in Maoxian county.展开更多
Interpretation results of RS images were taken as the foundation, ETM RS images of July 15, 2009 as the data source, ENVI was applied for the preprocessing, Arc GIS used to finish the interpretation, master data obtai...Interpretation results of RS images were taken as the foundation, ETM RS images of July 15, 2009 as the data source, ENVI was applied for the preprocessing, Arc GIS used to finish the interpretation, master data obtained, and VB used to complete program development. 12 representative landscape pattern indexes were selected, Excel data used to create Access database, and VB used to complete the program development. Selection of landscape pattern indexes, program development process and program usage were summarized, through comparing its results with Excel calculation results, it was found that calculation results of this program were correct, the usage was convenient, so needs of most users could be satisfied.展开更多
By using maximum likelihood classification, several landscape indexes have been adopted to evaluate landscape structure of the irrigated area of Hongsibao Town, and landscape pattern and dynamic change of Hongsibao in...By using maximum likelihood classification, several landscape indexes have been adopted to evaluate landscape structure of the irrigated area of Hongsibao Town, and landscape pattern and dynamic change of Hongsibao in 1989, 1999, 2003 and 2008 had been analyzed based on landscape patch, landscape type and transfer matrix. The results show that landscape pattern had changed obviously, patch number, fragmentation and dominance had increased, evenness had decreased, and landscape shape had become regular in the irrigated area of Hongsibao Town from 1989 to 2008. The primary landscape type in 1989 was grassland and in 2008 was sand, directly influenced by human activities.展开更多
The thermal-environment effect exists in the field of rapid urbanization. It has adverse effects on the urban atmosphere, re- gional climate, energy consumption, and public health. Shenzhen, a representative of rapidl...The thermal-environment effect exists in the field of rapid urbanization. It has adverse effects on the urban atmosphere, re- gional climate, energy consumption, and public health. Shenzhen, a representative of rapidly urbanizing cities in China, was selected as a case for pattern dynamics analysis of the thermal environment. The surface temperature was acquired from the thermal infrared data of Landsat TM and ETM+ images in 1986, 1995, and 2005 by Jim6nez-Mufioz and Sobrino's generalized single-channel method, which was used in assessing the distribution and spatial patterns of the thermal environment. The relative thermal environment curve (RTC) was combined with Moran's I analysis to assess the pattern dynamics of the thermal environment in different urbanization periods. Moran's I index and the RTC represent a process of aggregation-fragmentation-aggregation, which shows the aggregation pattern of a decrease during the rapid urbanization period and then an increase during the steady urbanization period. High-temperature areas gradually ex- panded to a uniform and scattered distribution in the rapid urbanization period; while the high thermal-environment effect was gradually transformed into a steady spatial pattern in the stable urbanization period. To characterize the increasing development in this multiple- center city, we chose profiles along an urban-development axis. The results suggest that heat islands have expanded from internal urban to external urban areas. Four profiles were obtained showing differences in shape due to spatial differences in the process of development.展开更多
The landscape pattern is affected by human activities and the natural environment.China’s urbanization has been a great achievement in the past 30 years,but also it has caused a variety of environmental problems.The ...The landscape pattern is affected by human activities and the natural environment.China’s urbanization has been a great achievement in the past 30 years,but also it has caused a variety of environmental problems.The landscape of the mountain valley area is particularly affected by human activities and the natural environment.The rise of remote sensing technologies has promoted a better understanding of ecological process,and the quantitative study on landscape dynamics has received more and more considerable attention.In this paper,four years from 2000,2005,2010,and 2015 were selected as the research time.Using Landsat TM/ETM remote sensing image,DEM,and socioeconomic data,we calculated the landscape pattern indices in four districts(Lishi,Fangshan,Liulin,and Zhongyang)of Luliang City on patch scale,land cover scale and landscape scale respectively.Thus,the change of landscape pattern in four districts from 2000 to 2015 were obtained.The results showed that:①the landscape in the mountain valley area has become more and more fragmented in the past 15 years(2000–2015);②the landscape dynamics of the main and tributary catchment areas of the Sanchuan River were different from that of urban development,which is closely related to the development stages of urban and rural areas;③there were differences in landscape changes between different topographic and landform units,and the landscape at higher altitudes was more vulnerable to disturbance.This study can provide some reference for the ecological restoration and management on landscape scale in the mountain and valley areas of the north and northwest China.展开更多
Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure,threatening the ecological balance.In order to study the trend of land use/cover and ...Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure,threatening the ecological balance.In order to study the trend of land use/cover and landscape pattern change and its relationship with water resources utilization in Manas River Basin,the land-use data of five periods in 1976,1990,2000,2010 and 2015 were analyzed.The results showed that:(1)During 1976-2015,farmland and construction land continuously increased,forest land and grassland continuously decreased,the water area initially reduced and then increased,the area of saline-alkali land initially increased and then reduced,the overall trend of unused land and the sandy area was decreasing and the area of different time periods is floating.The areas of land-use types either increased or decreased.This indicates that the landscape pattern of the basin changes dramatically,and human activities are the main reasons for this phenomenon;(2)The oasis area increased from 3480.2 km2 in 1976 to 7982.0 km2 in 2015,with an obvious increasing trend.The oasis area clearly increased during 1976-1990,the growth rate was 40.6%,the growth rate of the oasis area was 129.4%.In the last 40 years,the degree of desertification fluctuated and decreased.The increase of the oasis area directly leads to the increase of water resources utilization and aggravates the degree of water resources shortage;(3)The pattern of land-use types showed a non-equilibrium trend.In the region with increasing landscape heterogeneity,the overall landscape pattern was increasingly controlled by the majority of patches.The intensive land management model and drip irrigation under mulch have improved the utilization efficiency of water resources and saved water resources from engineering renovation and irrigation management.展开更多
China has experienced rapid urbanizations with dramatic land cover changes since 1978. Forest loss is one of land cover changes, and it induces various eco-environmental degradation issues. As one of China’s hotspot ...China has experienced rapid urbanizations with dramatic land cover changes since 1978. Forest loss is one of land cover changes, and it induces various eco-environmental degradation issues. As one of China’s hotspot regions, the Guangdong-Hong KongMacao Greater Bay Area(GBA) has undergone a dramatic urban expansion. To better understand forest dynamics and protect forest ecosystem, revealing the processes, patterns and underlying drivers of forest loss is essential. This study focused on the spatiotemporal evolution and potential driving factors of forest loss in the GBA at regional and city level. The Landsat time-series images from 1987 to2017 were used to derive forest, and landscape metrics and geographic information system(GIS) were applied to implement further spatial analysis. The results showed that: 1) 14.86% of the total urban growth area of the GBA was obtained from the forest loss in1987–2017;meanwhile, the forest loss area of the GBA reached 4040.6 km2, of which 25.60%(1034.42 km2) was converted to urban land;2) the percentages of forest loss to urban land in Dongguan(19.14%), Guangzhou(18.35%) and Shenzhen(15.81%) were higher than those in other cities;3) the forest became increasingly fragmented from 1987–2007, and then the fragmentation decreased from2007 to 2017);4) the landscape responses to forest changes varied with the scale;and 5) some forest loss to urban regions moved from low-elevation and gentle-slope terrains to higher-elevation and steep-slope terrains over time, especially in Shenzhen and Hong Kong.Urbanization and industrialization greatly drove forest loss and fragmentation, and, notably, hillside urban land expansion may have contributed to hillside forest loss. The findings will help policy makers in maintaining the stability of forest ecosystems, and provide some new insights into forest management and conservation.展开更多
The use of remote sensing in the design of land use mapping allows analyses of landscape evolution during a certain period of time which helps studies in a global scope.The objective of this study is to identify and a...The use of remote sensing in the design of land use mapping allows analyses of landscape evolution during a certain period of time which helps studies in a global scope.The objective of this study is to identify and analyze changes in characteristics of rural land use in the municipality of Passo Fundo,located in the state of Rio Grande do Sul,Brazil,during the years 2001 and 2020,through images taken from the Landsat TM-7 and TM-8 satellites.Methodologically,satellite images were classified by supervised methods,generating thematic maps,and taking into account the following groups:tillage(growing area),forest,exposed soil and water resources.Results demonstrated that the process of connecting agricultural crop patches went from 5.495 in 2001 to a figure of 10.812 in 2020,thus having an increase of 96%.展开更多
The aim of this study was to quantitatively evaluate the influences of landscape composition and spatial structure on the transmission process of non-point source pollutants in different regions.The location-weighted ...The aim of this study was to quantitatively evaluate the influences of landscape composition and spatial structure on the transmission process of non-point source pollutants in different regions.The location-weighted landscape contrast index,using the hydrological response unit(HRULCI)as the minimum research unit,was proposed in this paper.Through the description of the endemic landscape types and various geographical factors in the basin,the index calculation can reflect the impact of the“source-sink”landscape structure on the non-point source pollution in different regions and quantitatively evaluate the contribution of different landscape types and geographical factors to non-point source pollution.This study constructed a method of geo-cognitive computing for identifying“source-sink”landscape patterns of river basin non-point source pollution at two levels.1)The basin level:the spatial distribution and landscape combination of the entire basin are identified,and the crucial“source”and“sink”landscape types are obtained to measure the differences in the non-point source pollutant transmission processes between the“source”and“sink”landscapes in the different watersheds.2)The landscape level:HRULCI is calculated based on multiple geographical correction weighting factors.By using the idea of intersecting geographic information system(GIS)and landscape ecology,the landscape spatial pattern and ecological processes are linked.Compared with the traditional method for studying landscape patterns,the calculation of HRULCI makes the proposed method more ecologically significant.Lastly,a case study was evaluated to verify the significance of the proposed research method by taking the Yanshi River basin,a sub-basin belonging to the Jiulong River basin located in Fujian Province,China,as the experimental study zone.The results showed that this method can reflect the spatial distribution characteristics of the“source-sink”types and their relationship with non-point source pollution.By comparing the resulting calculation based on HRULCI,the risk of nutrient loss and the influence of landscape patterns and ecological processes on non-point pollution in different catchments can be obtained.展开更多
Based on Remote Sensing (RS) and Geographical Information System (GIS) technology,urban expansion of 75 cities in China from the 1970s to 2020 was reconstructed by visual-interpretation method,which described the grow...Based on Remote Sensing (RS) and Geographical Information System (GIS) technology,urban expansion of 75 cities in China from the 1970s to 2020 was reconstructed by visual-interpretation method,which described the growing process of urban lands and its influences on local land use structures synchronously.By employing annual expansion area per city and urban expansion density,spatial-temporal characteristics and macro patterns of urban expansion were analyzed from the aspects of regional-distributions,administrative-levels and population-sizes comprehensively.Results indicate that:1) urban expansion in China was universal,distinct,persistent,periodic and fluctuating.In the past five decades,urban lands of 75 monitored cities in China expanded dramatically from 3606.26 km2 to 30 521.13 km2.2) Though urban expansion presented significant differences from the aspects of regional distribution,administrative levels,and population sizes,it exhibited a deceleration trend in the 13th Five-Year Plan among all kinds of cities.3) Cultivated lands were the first land resource for urban expansion,and 55.17% of newly-expanded urban lands appeared by encroaching this land use type.China’s urban expansion has caused sustained pressure on cultivated land protection,especially in super megacities,and the contradiction between urban expansion and cultivated land protection will always exist.4) The compactness of urban lands in China increased before 1987 and reduced in the next three decades,which was consistent with the implementation of major policies and the deployment of national strategies,and is expected to become compact with a stopping declining or even rebounding after the 13th Five-Year Plan.展开更多
Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern...Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern dynamics. In this study, the Yellow River Delta was selected as the study area. By using 1986, 1993, 1996, 1999 and 2005 remote sensing data as basic information resource, with the support of GIS, a wetland vegetation spatial information dataset was built up. Through selecting the landscape metrics such as class area (CA), class percent of landscape (PL), number of patch (NP), largest patch index (LPI) and mean patch size (MPS) etc., the dynamics of vcgetation pattern was analyzed. The result showed that the change of vegetation pattern is significant from 1986 to 2005. From 1986-1999, the area of the vegetation, the percent of vegetation, LPI and MPS decreased, the NP increased, the vegetation pattern tends to be fragmental. The decrease in vegetation area may well be explained by the fact of the nature environment evolution (Climate change and decrease in Yellow River runoff) and the increase in the population in the Yellow River Delta. However, from 1999 2005, the area of the vegetation, the percent of vegetation, LPI and MPS increased, while the NP decreased. This trend of restoration may be due to the implementation of water resources regulation for the Yellow River Delta since 1999.展开更多
The decision tree and the threshold methods have been adopted to delineate boundaries and features of water bodies from LANDSAT images. After a spatial overlay analysis and using a remote sensing technique and the wet...The decision tree and the threshold methods have been adopted to delineate boundaries and features of water bodies from LANDSAT images. After a spatial overlay analysis and using a remote sensing technique and the wetland inventory data in Beijing, the water bodies were visually classified into different types of urban wetlands, and data on the urban wetlands of Beijing in 1986, 1991, 1996, 2000, 2002, 2004 and 2007 were obtained. Thirteen driving factors that affect wetland change were selected, and gray correlation analysis was employed to calculate the correlation between each driving factor and the total area of urban wetlands. Then, six major driving factors were selected based on the correlation coefficient, and the contribution rates of these six driving factors to the area change of various urban wetlands were calculated based on canonical correlation analysis. After that, this research analyzed the relationship and mechanism between the main driving factors and various types of wetlands. Five conclusions can be drawn. (1) The total area of surface water bodies in Beijing increased from 1986 to 1996, and gradually decreased from 1996 to 2007. (2) The areas of the river wetlands, water storage areas and pool and culture areas gradually decreased, and its variation tendency is consistent with that of the total area of wetlands. The area of the mining water areas and wastewater treatment plants slightly increased. (3) The six factors of driving forces are the annual rainfall, the evaporation, the quantity of inflow water, the volume of groundwater available, the urbanization rate and the daily average discharge of wastewater are the main factors affecting changes in the wetland areas, and they correlate well with the total area of wetlands. (4) The hydrologic indicators of water resources such as the quantity of inflow water and the volume of groundwater are the most important and direct driving forces that affect the change of the wetland area. These factors have a combined contribution rate of 43.94%. (5) Climate factors such as rainfall and evaporation are external factors that affect the changes in wetland area, and they have a contribution rate of 36.54%. (6) Human activities such as the urbanization rate and the daily average quantity of wastewater are major artificial driving factors. They have an influence rate of 19.52%.展开更多
Based on the remote sensing (RS) and geographic information system (GIS) analysis of the Landsat multispectral scanner (MSS) and thematic mapper (TM) satellite images of 1983, 1993, and 2005, the present research exam...Based on the remote sensing (RS) and geographic information system (GIS) analysis of the Landsat multispectral scanner (MSS) and thematic mapper (TM) satellite images of 1983, 1993, and 2005, the present research examined the effectiveness of the urban construction boundaries (UCBs) in containing urban growth within the 6th Ring Road of Beijing Municipality. Three indicators on boundary control were proposed, through which the effectiveness of boundary containment, land inventory sufficiency and illegal adjacent development to the UCBs were explored. The results suggested that, first, the UCBs were limited in effectiveness in containing urban growth; second, the area encompassed by the UCBs might not be designed large enough to accommodate new development. The frustration of the urban growth control through the UCBs mainly resulted from the lack of a transparent system for urban land use planning and control to provide sufficient information, the limitation of the traditional land use prediction method to consider contingencies, and the absence of a mechanism to monitor and adjust the UCBs to respond just in time to urban change.展开更多
The impervious surface area (ISA) at the regional scale is one of the important environmental factors for examining the interaction and mechanism of Land Use/Cover Change (LUCC)-ecosystem processes-climate change ...The impervious surface area (ISA) at the regional scale is one of the important environmental factors for examining the interaction and mechanism of Land Use/Cover Change (LUCC)-ecosystem processes-climate change under the interactions of urbanization and global environmental change. Timely and accurate extraction of ISA from remotely sensed data at the regional scale is challenging. This study explored the ISA extraction based on MODIS and DMSP-OLS data and the incorporation of China's land use/cover data. ISA datasets in Beijing-Tianjin-Tangshan Metropolitan Area (BTTMA) in 2000 and 2008 at a spatial resolution of 250 m were developed, their spatiotemporal changes were analyzed, and their impacts on water quality were then evaluated. The results indicated that ISA in BTTMA increased rapidly along urban fringe, transportation corridors and coastal belt both in intensity and extents from 2000 to 2008. Three cities (Tangshan, Langfang and Qinhuangdao) in Hebei Province had higher ISA growth rates than Beijing due to the pressure of population-resour- ces-environments in the city resulting in increasingly transferring industries to the nearby areas. The dense ISA distribution in BTTMA has serious impacts on water quality in the Haihe River watershed. Meanwhile, the proportion of ISA in sub-watersheds has significantly linear relationships with the densities of river COD and NH3-N.展开更多
文摘Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.
基金Human Geography provincial keystone subject of Henan University
文摘By using GIS and remote sensing techniques, the paper discusses how human activities have changed along the Yellow River in Henan province, China and how these altered activities have influenced the wetland landscape pattern change from 1987 to 2002. Results show that the total area of the wetland reduces dramatically compared to 1987, the total area of wetland reduces by 19.18%, the number of the patches in 2002 increases by 21.17%, the density increases by 50%, and the total perimeter increases by 1,290,491 m. Disturbed by human activities, landscape diversity index decreases from 1.1740 in 1987 to 0.9803 in 2002. During the last 20 years, the total area of the rice wetland increases, while the others decrease. Among those, the area of the bulrush wetland decreases most. In 1987, it takes 0.5% of the total area, but in 2002, it only takes 0.11%. The interpenetration of human influences on the wetland natural system has been long and close. The impacts of human activities on the spatial pattern of the wetland landscape along the Yellow River in Henan from 1987 to 2002 are great.
基金Sponsored by Study on Space-time Rules of Beijing Urban Green Space Ecosystem Regulating Rainwater Runoff and Control Countermeasures(31200531)
文摘With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators and planners to optimize the urban development areas and define the ecological protection red lines. Based on the SPOT images and field investigation data of urban green spaces within the sixth ring road of Beijing in 2000, 2005 and 2010, the study investigated the dynamic changes of urban green spaces in this area, by means of GIS techniques and landscape ecology methods. The results indicated that green spaces in Beijing have decreased by 207 km2 from 2000 to 2010 at the expense of agricultural lands and waters. Although there has been some increases in urban forests and grasslands, it cannot compensate the rapid decrease of urban green spaces. The land cover types conversion occurred mainly in the areas between the fifth and sixth ring roads while the zones encircled by the fourth ring road had a little change. In addition, landscape metrics such as number of patches(NP) and shape index(SHAPE) increased, but the mean nearest-neighbor distance(MNN), aggregation index(AI) and patch cohesion index(COHESION) decreased during the period of 2000-2010. Also green landscapes became considerably isolated and fragmented. The study disclosed the obvious changes of green space size, composition and layout in urban districts of Beijing City from 2000 to 2010, and highlighted that construction of urban green space should consider not only the geometric or aesthetic effect, but also the increase of vertical green volume and optimization of spatial layout to fully develop the ecological service functions of green spaces.
文摘Landscape pattern analysis is becoming the core to study global or local change. Incorporated with fast, dynamic and precise spatial information technology, Landscape pattern analysis has been a foundation for the governments to make decision. In this paper, Maoxian county, located in the northwest of Sichuan Province, was selected as the study area. Landsat TM data in 1994 and Landsat ETM data in 2002, with dates are just same as the time of national policy changes, are classified to make the landscape patterns change. The result indicates that, from 1994 to 2002, owing to the policies of the project of wild wood resource protect and the project of returning land for farming to forestry (grass), the forests has increased about 2.68%, Natural meadow has increased about 0.83%, Shrubby has increased about 0.63%, Farm land has decreased about 4.10% and the fragment of forests in 2002 is lower than in 1994. This states that the national policy actioned during 1990s have much positive influence on the landscape patterns in Maoxian county.
基金Supported by Social Development Program of Lianyungang Bureau of Science and Technology,Jiangsu Province:RS-based Research on the Eco-environment Evolution of Coastal Regions in Lianyungang(SH0811)~~
文摘Interpretation results of RS images were taken as the foundation, ETM RS images of July 15, 2009 as the data source, ENVI was applied for the preprocessing, Arc GIS used to finish the interpretation, master data obtained, and VB used to complete program development. 12 representative landscape pattern indexes were selected, Excel data used to create Access database, and VB used to complete the program development. Selection of landscape pattern indexes, program development process and program usage were summarized, through comparing its results with Excel calculation results, it was found that calculation results of this program were correct, the usage was convenient, so needs of most users could be satisfied.
文摘By using maximum likelihood classification, several landscape indexes have been adopted to evaluate landscape structure of the irrigated area of Hongsibao Town, and landscape pattern and dynamic change of Hongsibao in 1989, 1999, 2003 and 2008 had been analyzed based on landscape patch, landscape type and transfer matrix. The results show that landscape pattern had changed obviously, patch number, fragmentation and dominance had increased, evenness had decreased, and landscape shape had become regular in the irrigated area of Hongsibao Town from 1989 to 2008. The primary landscape type in 1989 was grassland and in 2008 was sand, directly influenced by human activities.
基金Under the auspices of National Natural Science Foundation of China (No. 41101175,40635028)
文摘The thermal-environment effect exists in the field of rapid urbanization. It has adverse effects on the urban atmosphere, re- gional climate, energy consumption, and public health. Shenzhen, a representative of rapidly urbanizing cities in China, was selected as a case for pattern dynamics analysis of the thermal environment. The surface temperature was acquired from the thermal infrared data of Landsat TM and ETM+ images in 1986, 1995, and 2005 by Jim6nez-Mufioz and Sobrino's generalized single-channel method, which was used in assessing the distribution and spatial patterns of the thermal environment. The relative thermal environment curve (RTC) was combined with Moran's I analysis to assess the pattern dynamics of the thermal environment in different urbanization periods. Moran's I index and the RTC represent a process of aggregation-fragmentation-aggregation, which shows the aggregation pattern of a decrease during the rapid urbanization period and then an increase during the steady urbanization period. High-temperature areas gradually ex- panded to a uniform and scattered distribution in the rapid urbanization period; while the high thermal-environment effect was gradually transformed into a steady spatial pattern in the stable urbanization period. To characterize the increasing development in this multiple- center city, we chose profiles along an urban-development axis. The results suggest that heat islands have expanded from internal urban to external urban areas. Four profiles were obtained showing differences in shape due to spatial differences in the process of development.
文摘The landscape pattern is affected by human activities and the natural environment.China’s urbanization has been a great achievement in the past 30 years,but also it has caused a variety of environmental problems.The landscape of the mountain valley area is particularly affected by human activities and the natural environment.The rise of remote sensing technologies has promoted a better understanding of ecological process,and the quantitative study on landscape dynamics has received more and more considerable attention.In this paper,four years from 2000,2005,2010,and 2015 were selected as the research time.Using Landsat TM/ETM remote sensing image,DEM,and socioeconomic data,we calculated the landscape pattern indices in four districts(Lishi,Fangshan,Liulin,and Zhongyang)of Luliang City on patch scale,land cover scale and landscape scale respectively.Thus,the change of landscape pattern in four districts from 2000 to 2015 were obtained.The results showed that:①the landscape in the mountain valley area has become more and more fragmented in the past 15 years(2000–2015);②the landscape dynamics of the main and tributary catchment areas of the Sanchuan River were different from that of urban development,which is closely related to the development stages of urban and rural areas;③there were differences in landscape changes between different topographic and landform units,and the landscape at higher altitudes was more vulnerable to disturbance.This study can provide some reference for the ecological restoration and management on landscape scale in the mountain and valley areas of the north and northwest China.
基金This work was financially supported by the National Natural Science Foundation of China(U1803244)Major scientific and technological projects of Xinjiang Production and Construction Corps(2017AA002)+3 种基金Science and Technology Research Project of Xinjiang Production and Construction Corps(2018AB027)Scientific Research Program of Shihezi University(KX00860105,KX008201,CXRC201801)Innovation and Development Support Program of Key Industries in Southern Xinjiang(2020DB001)Key Research and Development Program of National“13th Five-Year Plan”(2016YFC0501402).
文摘Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure,threatening the ecological balance.In order to study the trend of land use/cover and landscape pattern change and its relationship with water resources utilization in Manas River Basin,the land-use data of five periods in 1976,1990,2000,2010 and 2015 were analyzed.The results showed that:(1)During 1976-2015,farmland and construction land continuously increased,forest land and grassland continuously decreased,the water area initially reduced and then increased,the area of saline-alkali land initially increased and then reduced,the overall trend of unused land and the sandy area was decreasing and the area of different time periods is floating.The areas of land-use types either increased or decreased.This indicates that the landscape pattern of the basin changes dramatically,and human activities are the main reasons for this phenomenon;(2)The oasis area increased from 3480.2 km2 in 1976 to 7982.0 km2 in 2015,with an obvious increasing trend.The oasis area clearly increased during 1976-1990,the growth rate was 40.6%,the growth rate of the oasis area was 129.4%.In the last 40 years,the degree of desertification fluctuated and decreased.The increase of the oasis area directly leads to the increase of water resources utilization and aggravates the degree of water resources shortage;(3)The pattern of land-use types showed a non-equilibrium trend.In the region with increasing landscape heterogeneity,the overall landscape pattern was increasingly controlled by the majority of patches.The intensive land management model and drip irrigation under mulch have improved the utilization efficiency of water resources and saved water resources from engineering renovation and irrigation management.
基金Under the auspices of National Natural Science Foundation of China(No.41890854)Basic Research Program of Shenzhen Science and Technology Innovation Committee(No.JCYJ20180507182022554)+3 种基金National Key R&D Program of China(No.2017YFC0506200)National Natural Science Foundation of China(No.7181101150)National Natural Science Foundation of China(No.41901248)Shenzhen Future Industry Development Funding Program(No.201507211219247860)。
文摘China has experienced rapid urbanizations with dramatic land cover changes since 1978. Forest loss is one of land cover changes, and it induces various eco-environmental degradation issues. As one of China’s hotspot regions, the Guangdong-Hong KongMacao Greater Bay Area(GBA) has undergone a dramatic urban expansion. To better understand forest dynamics and protect forest ecosystem, revealing the processes, patterns and underlying drivers of forest loss is essential. This study focused on the spatiotemporal evolution and potential driving factors of forest loss in the GBA at regional and city level. The Landsat time-series images from 1987 to2017 were used to derive forest, and landscape metrics and geographic information system(GIS) were applied to implement further spatial analysis. The results showed that: 1) 14.86% of the total urban growth area of the GBA was obtained from the forest loss in1987–2017;meanwhile, the forest loss area of the GBA reached 4040.6 km2, of which 25.60%(1034.42 km2) was converted to urban land;2) the percentages of forest loss to urban land in Dongguan(19.14%), Guangzhou(18.35%) and Shenzhen(15.81%) were higher than those in other cities;3) the forest became increasingly fragmented from 1987–2007, and then the fragmentation decreased from2007 to 2017);4) the landscape responses to forest changes varied with the scale;and 5) some forest loss to urban regions moved from low-elevation and gentle-slope terrains to higher-elevation and steep-slope terrains over time, especially in Shenzhen and Hong Kong.Urbanization and industrialization greatly drove forest loss and fragmentation, and, notably, hillside urban land expansion may have contributed to hillside forest loss. The findings will help policy makers in maintaining the stability of forest ecosystems, and provide some new insights into forest management and conservation.
文摘The use of remote sensing in the design of land use mapping allows analyses of landscape evolution during a certain period of time which helps studies in a global scope.The objective of this study is to identify and analyze changes in characteristics of rural land use in the municipality of Passo Fundo,located in the state of Rio Grande do Sul,Brazil,during the years 2001 and 2020,through images taken from the Landsat TM-7 and TM-8 satellites.Methodologically,satellite images were classified by supervised methods,generating thematic maps,and taking into account the following groups:tillage(growing area),forest,exposed soil and water resources.Results demonstrated that the process of connecting agricultural crop patches went from 5.495 in 2001 to a figure of 10.812 in 2020,thus having an increase of 96%.
基金funded by the National Key R&D Programs of China(Grant No.2017YFB0504201,2015BAJ02B02)the Natural Science Foundation of China(Grant No.61473286,61375002)the Natural Science Foundation of Hainan Province(Grant No.20164178).
文摘The aim of this study was to quantitatively evaluate the influences of landscape composition and spatial structure on the transmission process of non-point source pollutants in different regions.The location-weighted landscape contrast index,using the hydrological response unit(HRULCI)as the minimum research unit,was proposed in this paper.Through the description of the endemic landscape types and various geographical factors in the basin,the index calculation can reflect the impact of the“source-sink”landscape structure on the non-point source pollution in different regions and quantitatively evaluate the contribution of different landscape types and geographical factors to non-point source pollution.This study constructed a method of geo-cognitive computing for identifying“source-sink”landscape patterns of river basin non-point source pollution at two levels.1)The basin level:the spatial distribution and landscape combination of the entire basin are identified,and the crucial“source”and“sink”landscape types are obtained to measure the differences in the non-point source pollutant transmission processes between the“source”and“sink”landscapes in the different watersheds.2)The landscape level:HRULCI is calculated based on multiple geographical correction weighting factors.By using the idea of intersecting geographic information system(GIS)and landscape ecology,the landscape spatial pattern and ecological processes are linked.Compared with the traditional method for studying landscape patterns,the calculation of HRULCI makes the proposed method more ecologically significant.Lastly,a case study was evaluated to verify the significance of the proposed research method by taking the Yanshi River basin,a sub-basin belonging to the Jiulong River basin located in Fujian Province,China,as the experimental study zone.The results showed that this method can reflect the spatial distribution characteristics of the“source-sink”types and their relationship with non-point source pollution.By comparing the resulting calculation based on HRULCI,the risk of nutrient loss and the influence of landscape patterns and ecological processes on non-point pollution in different catchments can be obtained.
基金Under the auspices of the National Key R&D Program of China (No. 2017YFE0104600)。
文摘Based on Remote Sensing (RS) and Geographical Information System (GIS) technology,urban expansion of 75 cities in China from the 1970s to 2020 was reconstructed by visual-interpretation method,which described the growing process of urban lands and its influences on local land use structures synchronously.By employing annual expansion area per city and urban expansion density,spatial-temporal characteristics and macro patterns of urban expansion were analyzed from the aspects of regional-distributions,administrative-levels and population-sizes comprehensively.Results indicate that:1) urban expansion in China was universal,distinct,persistent,periodic and fluctuating.In the past five decades,urban lands of 75 monitored cities in China expanded dramatically from 3606.26 km2 to 30 521.13 km2.2) Though urban expansion presented significant differences from the aspects of regional distribution,administrative levels,and population sizes,it exhibited a deceleration trend in the 13th Five-Year Plan among all kinds of cities.3) Cultivated lands were the first land resource for urban expansion,and 55.17% of newly-expanded urban lands appeared by encroaching this land use type.China’s urban expansion has caused sustained pressure on cultivated land protection,especially in super megacities,and the contradiction between urban expansion and cultivated land protection will always exist.4) The compactness of urban lands in China increased before 1987 and reduced in the next three decades,which was consistent with the implementation of major policies and the deployment of national strategies,and is expected to become compact with a stopping declining or even rebounding after the 13th Five-Year Plan.
文摘Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern dynamics. In this study, the Yellow River Delta was selected as the study area. By using 1986, 1993, 1996, 1999 and 2005 remote sensing data as basic information resource, with the support of GIS, a wetland vegetation spatial information dataset was built up. Through selecting the landscape metrics such as class area (CA), class percent of landscape (PL), number of patch (NP), largest patch index (LPI) and mean patch size (MPS) etc., the dynamics of vcgetation pattern was analyzed. The result showed that the change of vegetation pattern is significant from 1986 to 2005. From 1986-1999, the area of the vegetation, the percent of vegetation, LPI and MPS decreased, the NP increased, the vegetation pattern tends to be fragmental. The decrease in vegetation area may well be explained by the fact of the nature environment evolution (Climate change and decrease in Yellow River runoff) and the increase in the population in the Yellow River Delta. However, from 1999 2005, the area of the vegetation, the percent of vegetation, LPI and MPS increased, while the NP decreased. This trend of restoration may be due to the implementation of water resources regulation for the Yellow River Delta since 1999.
基金National Natural Science Foundation of China, No.41171318 No.41001160+6 种基金 The Fundamental Research Funds for the Central Universities, the Beijing Plan Program of Science and Technology, No.D08040600580801 International Program for Cooperation in Science and Technology, No.2009DFA 91710 Beijing Forestry Survey and Design Institute provided the data and report of the wetland inventory. We would like to express our sincere appreciation for their suggestions, support and help. They are Prof. Ji Wei of University of Missouri-Kansas City Xue Li, Jianrui Zheng and Lingmei Huang of the Beijing Normal University Shiwu Gao, Gongying Yuan, Zhihua Yang and Zailan Yang of the Beijing Landscape Administration Liyuan Cui of the Chinese Academy of Forestry Jinzeng Wang of the Beijing Forestry Survey and Design Institute and Wenji Zhao, Lin Zhn and Zhaoning Gong of the Capital Normal University.
文摘The decision tree and the threshold methods have been adopted to delineate boundaries and features of water bodies from LANDSAT images. After a spatial overlay analysis and using a remote sensing technique and the wetland inventory data in Beijing, the water bodies were visually classified into different types of urban wetlands, and data on the urban wetlands of Beijing in 1986, 1991, 1996, 2000, 2002, 2004 and 2007 were obtained. Thirteen driving factors that affect wetland change were selected, and gray correlation analysis was employed to calculate the correlation between each driving factor and the total area of urban wetlands. Then, six major driving factors were selected based on the correlation coefficient, and the contribution rates of these six driving factors to the area change of various urban wetlands were calculated based on canonical correlation analysis. After that, this research analyzed the relationship and mechanism between the main driving factors and various types of wetlands. Five conclusions can be drawn. (1) The total area of surface water bodies in Beijing increased from 1986 to 1996, and gradually decreased from 1996 to 2007. (2) The areas of the river wetlands, water storage areas and pool and culture areas gradually decreased, and its variation tendency is consistent with that of the total area of wetlands. The area of the mining water areas and wastewater treatment plants slightly increased. (3) The six factors of driving forces are the annual rainfall, the evaporation, the quantity of inflow water, the volume of groundwater available, the urbanization rate and the daily average discharge of wastewater are the main factors affecting changes in the wetland areas, and they correlate well with the total area of wetlands. (4) The hydrologic indicators of water resources such as the quantity of inflow water and the volume of groundwater are the most important and direct driving forces that affect the change of the wetland area. These factors have a combined contribution rate of 43.94%. (5) Climate factors such as rainfall and evaporation are external factors that affect the changes in wetland area, and they have a contribution rate of 36.54%. (6) Human activities such as the urbanization rate and the daily average quantity of wastewater are major artificial driving factors. They have an influence rate of 19.52%.
基金Project supported by the National Natural Science Foundation of China (No. 50678088)the National Key Technology R&D Program (No. 2006BAJ14B08)the Postdoctoral Science Foundation of China (No. 20080430210)
文摘Based on the remote sensing (RS) and geographic information system (GIS) analysis of the Landsat multispectral scanner (MSS) and thematic mapper (TM) satellite images of 1983, 1993, and 2005, the present research examined the effectiveness of the urban construction boundaries (UCBs) in containing urban growth within the 6th Ring Road of Beijing Municipality. Three indicators on boundary control were proposed, through which the effectiveness of boundary containment, land inventory sufficiency and illegal adjacent development to the UCBs were explored. The results suggested that, first, the UCBs were limited in effectiveness in containing urban growth; second, the area encompassed by the UCBs might not be designed large enough to accommodate new development. The frustration of the urban growth control through the UCBs mainly resulted from the lack of a transparent system for urban land use planning and control to provide sufficient information, the limitation of the traditional land use prediction method to consider contingencies, and the absence of a mechanism to monitor and adjust the UCBs to respond just in time to urban change.
基金The Young Scientist Fund of National Natural Science Foundation of China, No.40901224 National Basic Research Program of China, No.2010CB950900+1 种基金 Open Fund of State Key Laboratory of Remote Sensing Science, No.2009KFJJ005 Open Fund of State Key Lab of Resources and Environmental Information System, No.A0725
文摘The impervious surface area (ISA) at the regional scale is one of the important environmental factors for examining the interaction and mechanism of Land Use/Cover Change (LUCC)-ecosystem processes-climate change under the interactions of urbanization and global environmental change. Timely and accurate extraction of ISA from remotely sensed data at the regional scale is challenging. This study explored the ISA extraction based on MODIS and DMSP-OLS data and the incorporation of China's land use/cover data. ISA datasets in Beijing-Tianjin-Tangshan Metropolitan Area (BTTMA) in 2000 and 2008 at a spatial resolution of 250 m were developed, their spatiotemporal changes were analyzed, and their impacts on water quality were then evaluated. The results indicated that ISA in BTTMA increased rapidly along urban fringe, transportation corridors and coastal belt both in intensity and extents from 2000 to 2008. Three cities (Tangshan, Langfang and Qinhuangdao) in Hebei Province had higher ISA growth rates than Beijing due to the pressure of population-resour- ces-environments in the city resulting in increasingly transferring industries to the nearby areas. The dense ISA distribution in BTTMA has serious impacts on water quality in the Haihe River watershed. Meanwhile, the proportion of ISA in sub-watersheds has significantly linear relationships with the densities of river COD and NH3-N.