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1.
Landscape patterns in a region have different sizes, shapes and spatial arrangements, which contribute to the spatial heterogeneity of the landscape and are linked to the distinct behavior of thermal environments. There is a lack of research generating landscape metrics from discretized percent impervious surface area data (ISA), which can be used as an indicator of urban spatial structure and level of development, and quantitatively characterizing the spatial patterns of landscapes and land surface temperatures (LST). In this study, linear spectral mixture analysis (LSMA) is used to derive sub-pixel ISA. Continuous fractional cover thresholds are used to discretize percent ISA into different categories related to urban land cover patterns. Landscape metrics are calculated based on different ISA categories and used to quantify urban landscape patterns and LST configurations. The characteristics of LST and percent ISA are quantified by landscape metrics such as indices of patch density, aggregation, connectedness, shape and shape complexity. The urban thermal intensity is also analyzed based on percent ISA. The results indicate that landscape metrics are sensitive to the variation of pixel values of fractional ISA, and the integration of LST, LSMA. Landscape metrics provide a quantitative method for describing the spatial distribution and seasonal variation in urban thermal patterns in response to associated urban land cover patterns. 相似文献
2.
景观格局是研究景观功能和动态的基础。景观指数分析在土地利用/土地覆盖、生态系统服务、森林监控、城市蔓生以及生物多样性等方面应用广泛。现有许多景观指数之间存在不同程度的相关性,不仅导致信息冗余,还将影响结果解译的清晰性和准确性。同时,已有研究主要针对栅格数据,针对矢量数据的景观指数分析研究较少。为解决上述问题,以广州市土地利用景观格局为例,在矢量数据格式下计算了44个常用的景观指数,并运用相关分析和因子分析相结合的多元统计分析法,提取了6个核心景观指数,这些指数描述了广州市土地利用景观格局的6个维度:景观破碎度、平均斑块面积、平均形状复杂度、空间分散度、形状复杂度差异和土地类型的相似性。 相似文献
3.
This paper investigates the spatial heterogeneity of three landscapes along an altitudinal gradient and different human land use. The main aim was the identification of appropriate landscape indicators using different extents. ASTER image was used to create a land cover map consisting of three landscapes which differed in altitude and land use. A number of landscape metrics quantifying patch complexity, configuration, diversity and connectivity were derived from the thematic map at the landscape level. There were significant differences among the three landscapes regarding these four aspects of landscape heterogeneity. The analysis revealed a specific pattern of land use where lowlands are being increasingly utilized by humans (percentage of agricultural land = 65.84%) characterized by physical connectedness (high values of Patch Cohesion Index) and relatively simple geometries (low values of fractal dimension index). The landscape pattern of uplands was found to be highly diverse based upon the Shannon Diversity index. After selecting the scale (600 ha) where metrics values stabilized, it was shown that metrics were more correlated at the small scale of 60 ha. From the original 24 metrics, 14 individual metrics with high Spearman correlation coefficient and Variance Inflation Factor criterion were eliminated, leaving 10 representative metrics for subsequent analysis. Data reduction analysis showed that Patch Density, Area-Weighted Mean Fractal Dimension Index and Patch Cohesion Index are suitable to describe landscape patterns irrespective of the scale. A systematic screening of these metrics could enhance a deeper understanding of the results obtained by them and contribute to a sustainable landscape management of Mediterranean landscapes. 相似文献
4.
Changes in landscape composition and configuration patterns of Sancaktepe Municipal District in the Asian side of Istanbul Metropolitan City of Turkey were analysed using landscape metrics. Class-level and landscape-level metrics were calculated from the land cover/land use data using Patch Analyst, an extension in the Arc View GIS. The land cover/land use data were derived from classified satellite images of Landsat Thematic Mapper of 2002 and 2009 for Sancaktepe District. There was evidence of increase in agglomeration process of built-up patches as indicated by the increases in mean patch size, decrease in total edge and number of patches between 2002 and 2009. The urban expansion pattern experienced overall was not fragmented but concentrated due to infilling around existing patches. Changes in Area-Weighted Mean Shape Index and Area-Weighted Patch Fractal Dimension Index indicated that the physical shapes within built-up, forest and bareland areas were relatively complex and irregular. A conclusion is made in this study that spatial metrics are useful tools to describe the urban landscape composition and configuration in its various aspects and certain decisions whether to approve a specific development in urban planning could, for example, be based on some measures of urban growth form or pattern in terms of uniformity and irregularity, attributable to the dynamic processes of agglomeration and fragmentation of land cover/land use patches caused by urban expansion. 相似文献
5.
Area Delineation and Spatial-Temporal Dynamics of Urban Heat Island in Lanzhou City,China Using Remote Sensing Imagery 总被引：2，自引：0，他引：2
Jinghu Pan 《Journal of the Indian Society of Remote Sensing》2016,44(1):111-127
One of the key impacts of rapid urbanization on the environment is the effect of urban heat island (UHI). By using the Landsat TM/ETM+ thermal infrared remote sensing data of 1993, 2001 and 2011 to retrieve the land surface temperature (LST) of Lanzhou City, and by adopting object-oriented fractal net evolution approach (FNEA) to make image segmentation of the LST, the UHI elements were extracted. The G* index spatial aggregation analysis was made to calculate the urban heat island ratio index (URI), and the landscape metrics were used to quantify the changes of the spatial pattern of the UHI from the aspects of quantity, shape and structure. The impervious surface distribution and vegetation coverage were extracted by a constrained linear spectral mixture model to explore the relationships of the impervious surface distribution and vegetation coverage with the UHI. The information of urban built-up area was extracted by using UBI (NDBI-NDVI) index, and the effects of urban expansion on city thermal environment were quantitatively analyzed, with the URI and the LST grade maps built. In recent 20 years, the UHI effect in Lanzhou City was strengthened, with the URI increased by 1.4 times. The urban expansion had a spatiotemporal consistency with the UHI expansion. The patch number and density of the UHI landscape were increased, the patch shape and the whole landscape tended to be complex, the landscape became more fragmented, and the landscape connectivity was decreased. The heat island strength had a negative linear correlation with the urban vegetation coverage, and a positive logarithmic correlation with the urban impervious surface coverage. 相似文献
6.
Pammi Nitin Sinha Nilanchal Patel Ayyemperumal T. Jeyaseelan Vivek K. Singh 《Journal of the Indian Society of Remote Sensing》2011,39(2):225-233
Urbanization incepts serious challenges of growth and its management. The issues of urbanization manifest in the form of overcrowding,
congestion, insufficient infrastructure, inadequate service provisioning, environmental degradation, pollution etc and affect
the socioeconomic development of the city. Ranchi, the capital of newly formed state of Jharkhand (India) has been witnessing
the same scenario; raising the question of its planning and management of growth to make it more efficient and sustainable.
It hoists the necessity to study the pattern of urbanization and its impact on other landuse/landcover categories in Ranchi
city. In order to assess the urbanization pattern and spatio-temporal dynamics in the study area, the changing pattern of
the three significant patch parameters viz. patch frequency, largest patch size and average patch size of all affected landuse/landcover
categories over a time gradient representing the pre-capital and post-capital formation phases of the Ranchi city have been
analyzed. The two conventional landscape indices viz. Shannon’s diversity Index and Simpson’s diversity index and a newly
developed index ‘Normalized Patch size Range Index’ have been employed in the analyses which not only ascertained the finding
derived but also provided meaningful insights pertaining to the spatio-temporal urban landscape dynamics prevailing in the
Ranchi city. 相似文献
7.
8.
道路网元胞的组成及其配置构成了特定的网络景观,受启发于元胞和景观格局中斑块的相似性,借鉴景观格局分析中的景观指数分析法,提出了一种城市道路网元胞模式分析的新方法——网络景观指数分析法。该方法基于道路类型生成不同类别的元胞,计算网络景观指数,并通过相关分析与因子分析挖掘主要因子,进而解释主要因子及代表指数在道路网模式分析中的含义。应用该方法计算了中国34个城市街道网络的24个指标,发现了4个主要因子:元胞的空间分布与多样性、元胞最大尺寸与延展性差异、元胞平均延展性和元胞平均尺寸与形状复杂度。反映到道路网中,描述了道路的集聚与分散特征、道路类型的多样性、道路网的规则程度等特征。 相似文献
9.
根据相同土地利用类型景观格局特征相似的原理,在传统遥感分类方法的基础上,结合景观生态学理论,建立了土地利用分类新方法; 应用SPOT遥感图像提取了北京市五环内的居民用地和非居民用地类型,总分类精度达到了85.9%,Kappa系数为71.1%.本研究结合学科交叉的优势,为遥感技术应用和土地利用信息提取提供了新思路. 相似文献
10.
Since there is an increasing demand for integrating landscape ecology and urban planning theories to study complex urban ecosystems and establish rational and ecological urban planning, we introduced a new concept-urban functional landscapes which can be reclassified based on detailed land use data to fulfill the various urban functions, such as residential, commercial, industrial, and infrastructure purposes. In this paper, urban functional landscapes were defined based on urban land use data produced from Pleiades images, and then landscape metrics and population density were combined to identify the urban functional zones along an urban–rural gradient. The features of urban functional landscape patterns and population density were also analyzed, and their relationship has been explored. The results showed that the pattern of urban functional landscapes and population density in the urban functional zones (Urban center, Urban peripheral area, Landscape barrier, Satellite city and Far-suburb) along the urban–rural gradient in Xiamen doesn't totally conform to the classical theories in spatial and social aspects. Urban functional landscapes is potential of acting as bridges between the landscape ecology and urban planning theories, providing scientific support for rational urban landscape planning and urban land use policy making. 相似文献
11.
This study proposes a landscape metrics-based method for model performance evaluation of land change simulation models. To quantify model performance at both landscape and class levels, a set of composition- and configuration-based metrics including number of patches, class area, landscape shape index, mean patch area and mean Euclidean nearest neighbour distance were employed. These landscape metrics provided detailed information on simulation success of a cellular automata-Markov chain (CA-Markov) model standpoint of spatial arrangement of the simulated map versus the corresponding reference layer. As a measure of model simulation success, mean relative error (MRE) of the metrics was calculated. At both landscape and class levels, the MRE values were accounted for 22.73 and 10.2%, respectively, which are further categorised into qualitative measurements of model simulation performance for simple and quick comparison of the results. Findings of the present study depict a hierarchical and multi spatial level assessment of model performance. 相似文献
12.
Assessment of forest fragmentation in the conservation priority Dudhwa landscape,India using FRAGSTATS computed class level metrics 总被引：1，自引：0，他引：1
The Dudhwa landscape, a priority conservation area representing Terai ecosystem (woodland-grassland-wetland complex) has witnessed
a sea change in past 150 years or so on account of long history of forest management, changes in land use, and rapid economic
development. We assessed fragmentation in two constituent protected areas (Dudhwa National Park-DNP and Katerniaghat Wildlife
Sanctuary-KAT) of the landscape due to forest management activities (clear cutting, development of rail and road network,
and plantations) and compared the magnitude among them using select metrics at the forest class level. We applied FRAGSTATS
spatial pattern analysis software (ver.3.3) on different forest classes deciphered by land use/ cover maps generated using
IRS P6 LISS IV digital data. Study amply revealed that the forests in DNP are less fragmented and of better habitat quality
than forests of KAT. The set of seven metrics (patch density, mean patch size, edge density, mean shape index, mean core area,
mean nearest neighbour, and interspersion and juxtaposition index) at the class level quantified in the present study are
simple and proved useful for quantifying complex spatial processes and can be used as an effective means of monitoring in
Dudhwa landscape. 相似文献
13.
This study investigates urbanization and its potential environmental consequences in Shanghai and Stockholm metropolitan areas over two decades. Changes in land use/land cover are estimated from support vector machine classifications of Landsat mosaics with grey-level co-occurrence matrix features. Landscape metrics are used to investigate changes in landscape composition and configuration and to draw preliminary conclusions about environmental impacts. Speed and magnitude of urbanization is calculated by urbanization indices and the resulting impacts on the environment are quantified by ecosystem services. Growth of urban areas and urban green spaces occurred at the expense of cropland in both regions. Alongside a decrease in natural land cover, urban areas increased by approximately 120% in Shanghai, nearly ten times as much as in Stockholm, where the most significant land cover change was a 12% urban expansion that mostly replaced agricultural areas. From the landscape metrics results, it appears that fragmentation in both study regions occurred mainly due to the growth of high density built-up areas in previously more natural/agricultural environments, while the expansion of low density built-up areas was for the most part in conjunction with pre-existing patches. Urban growth resulted in ecosystem service value losses of approximately 445 million US dollars in Shanghai, mostly due to the decrease in natural coastal wetlands while in Stockholm the value of ecosystem services changed very little. Total urban growth in Shanghai was 1768 km2 and 100 km2 in Stockholm. The developed methodology is considered a straight-forward low-cost globally applicable approach to quantitatively and qualitatively evaluate urban growth patterns that could help to address spatial, economic and ecological questions in urban and regional planning. 相似文献
14.
基于GIS和景观生态学的土地整理景观研究 总被引：1，自引：0，他引：1
运用GIS技术和景观生态学理论方法,以安徽省淮南市潘集区市级投资重点土地整理项目为例,选取3类景观指标,对项目区内土地整理前后的土地利用现状和景观格局变化情况进行研究。结果表明： 景观类型中水田斑块占绝对优势,斑块分维数、形状指数呈下降趋势,表明斑块形状趋于规则和简单; 斑块数量和斑块密度降低,平均斑块面积和最大斑块面积增加,最大斑块指数增大,景观破碎度降低; 平均分维数和平均形状指数增大,表明景观形状较整理前变得规则,但总体形态变得复杂; 多样性指数和均匀度指数降低,表明在增加了景观分布均匀程度的同时降低了景观的多样性,景观类型有所减少。 相似文献
15.
Sermin Tagil Sevgi Gormus Serhat Cengiz 《Journal of the Indian Society of Remote Sensing》2018,46(8):1285-1296
Perforation, dissection, fragmentation, shrinkage and attrition in ecosystems take place due to urbanization. In this study, where and when temporal and spatial heterogeneity occurs is tried to be explained by taking human intervention in landscape pattern and processes in and around the city of Denizli into account and how this heterogeneity affects habitat conditions within the scope of landscape ecology. Landscape pattern metrics were estimated in order to reveal the change in habitats and present the properties of the landscape. 30 pattern indicators on class and pattern levels, which are important to show human–environment interaction, were analyzed in order to indicate the features of the landscape such as area, side, shape and dispersion. To this end, LANDSAT TM/7–ETM/8-OLI satellite images of 1987 and 2013 were classified for laying the foundations of the analysis. Analyses showed that between 1987 and 2013, complicated shape features, increase in edge habitats, de-growth in core areas and eventually fragmentation in landscape have been dominant. Heterogenic structure in landscape has increased. This points not to the self-functioning of the landscape, but to the domination of human intervention over the landscape. Particularly, due to urban growth and sprawl, fragmentation, isolation and habitat loss in croplands have increased. This study sets forth the usefulness of remote sensing, GIS and landscape metrics in understanding how urban dynamics and ecosystems change in developing urban politics. 相似文献
16.
Rapid urbanization threatens urban green spaces and vegetation, demonstrated by a decrease in connectivity and higher levels of fragmentation. Understanding historic spatial and temporal patterns of such fragmentation is important for habitat and biological conservation, ecosystem management and urban planning. Despite their potential value, Local Indicators of Spatial Autocorrelation (LISA) measures have not been sufficiently exploited in monitoring the spatial and temporal variability in clustering and fragmentation of vegetation patterns in urban areas. LISA statistics are an important structural measure that indicates the presence of outliers, zones of similarity (hot spots) and of dissimilarity (cold spots) at proximate locations, hence they could be used to explicitly capture spatial patterns that are clustered, dispersed or random. In this study, we applied landscape metrics, LISA indices to analyse the temporal variability in clustering and fragmentation patterns of vegetation patches in Harare metropolitan city, Zimbabwe using Landsat series data for 1994, 2001 and 2017. Analysis of landscape metrics showed an increase in the fragmentation of vegetation patches between 1994–2017 as shown by the decrease in mean patch size, an increase in number of patches, edge density and shape complexity of vegetation patches. The study further demonstrates the utility of LISA indices in identifying key hot spot and cold spots. Comparatively, the highly vegetated northern parts of the city were characterised by significantly high positive spatial autocorrelation (p < 0.05) of vegetation patches. Conversely, more dispersed vegetation patches were found in the highly and densely urbanized western, eastern and southern parts of the city. This suggest that with increasing vegetation fragmentation, small and isolated vegetation patches do not spatially cluster but are dispersed geographically. The findings of the study underline the potential of LISA measures as a valuable spatially explicit method for the assessment of spatial clustering and fragmentation of urban vegetation patterns. 相似文献
17.
三峡水库建设前后10年库区景观空间格局动态变化研究——以重庆开县为例 总被引：2，自引：1，他引：1
在遥感和地理信息系统技术的支持下,以1992年和2002年TM图像为基础,采用斑块密度、斑块平均面积、景观形状指数、景观分离度指数、景观多样性指数、景观优势度指数、景观相对聚集度指数深入而全面地研究了三峡工程建设前后十年重庆开县景观空间格局的动态变化,本研究的开展旨在为库区生态环境保护提供科学依据。研究结果表明,十年间研究区景观空间格局发生了明显变化,草地、未利用地、旱地、果园和水田面积净减,森林、建设用地、灌木林和水域面积增加,退耕还林已初见成效。 相似文献
18.
AbstractDeveloping countries like India are an urbanization hotspot with many upcoming towns and cities. Growth in small and medium sized towns and cities have been unnoticed and growing without appropriate urban planning. Utilizing the available medium resolution satellite data and geospatial platforms, the growth dynamics of Kurukshetra city was analysed over a period of 24 years. The study employed a combination of change detection technique and spatial metrics (six each of class and landscape levels) analysis to delineate the growth track of the city and its environs. A significant increase in urban built up (dense 237%; open 1038%) is seen majorly at the cost of open area (70%) and tree clad (58%). Phases of city’s aggregation and diffusion are observed using class and landscape level spatial metrics. Understanding and monitoring of land use changes in and around city limits using integrated spatial tools provide better decision making capability. 相似文献
19.
In India the last 30 years had witnessed a radical transformation of urban scene. In particular, during this period, the one
lakh cities and million plus cities began to grow rapidly. In the present study, urban growth of Jaipur city in the last 31 years
(1975–2006) was assessed. Jaipur ranks 11th in India with a total population of 2.3 million and has shown a consistent increase
in the past 50 years. It is one of the fastest growing mega cities of the country with an annual average growth rate of 4.5%
which is quite high from the national urban growth rate. Remote sensing and GIS have been used to extract the information
related to urban growth-built up area and its spatial and temporal variation. The Shannon’s entropy at two levels (city as
a whole and ward wise) is computed in order to quantify the form and patterns of urban growth using built up area as spatial
phenomena. Further, multivariate statistical techniques have been used to establish the relationship between the urban growth
and its causative and determining factors. Results of this study reveal that the growth rate of built up in Jaipur has outstripped
the rate of population growth. Shannon’s entropy quantifies as dispersed form of urban growth till 2000 and after it, there
is relative compactness in 2006. 相似文献
20.
Urban heat islands (UHIs) have attracted attention around the world because they profoundly affect biological diversity and human life. Assessing the effects of the spatial structure of land use on UHIs is essential to better understanding and improving the ecological consequences of urbanization. This paper presents the radius fractal dimension to quantify the spatial variation of different land use types around the hot centers. By integrating remote sensing images from the newly launched HJ-1B satellite system, vegetation indexes, landscape metrics and fractal dimension, the effects of land use patterns on the urban thermal environment in Wuhan were comprehensively explored. The vegetation indexes and landscape metrics of the HJ-1B and other remote sensing satellites were compared and analyzed to validate the performance of the HJ-1B. The results have showed that land surface temperature (LST) is negatively related to only positive normalized difference vegetation index (NDVI) but to Fv across the entire range of values, which indicates that fractional vegetation (Fv) is an appropriate predictor of LST more than NDVI in forest areas. Furthermore, the mean LST is highly correlated with four class-based metrics and three landscape-based metrics, which suggests that the landscape composition and the spatial configuration both influence UHIs. All of them demonstrate that the HJ-1B satellite has a comparable capacity for UHI studies as other commonly used remote sensing satellites. The results of the fractal analysis show that the density of built-up areas sharply decreases from the hot centers to the edges of these areas, while the densities of water, forest and cropland increase. These relationships reveal that water, like forest and cropland, has a significant effect in mitigating UHIs in Wuhan due to its large spatial extent and homogeneous spatial distribution. These findings not only confirm the applicability and effectiveness of the HJ-1B satellite system for studying UHIs but also reveal the impacts of the spatial structure of land use on UHIs, which is helpful for improving the planning and management of the urban environment. 相似文献