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以1987年和2000年TM影像为数据源,在ENVI 4.4平台下提取淮北市(相山建成区)1987-2000年土地利用/覆盖动态变化信息,利用FRAGSTATS 3.3软件提取研究区的斑块指数、多样性指数、优势度、破碎度、分维度及形状指数等景观格局指标,并进行分析. 相似文献
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Assessing Impacts of Typhoons and the Chi-Chi Earthquake on Chenyulan Watershed Landscape Pattern in Central Taiwan Using Landscape Metrics 总被引:2,自引:1,他引:2
The Chi-Chi earthquake (ML = 7.3) occurred in the central part of Taiwan on September 21, 1999. After the earthquake, typhoons Xangsane and Toraji produced
heavy rainfall that fell across the eastern and central parts of Taiwan on November 2000 and July 2001. This study uses remote
sensing data, landscape metrics, multivariate statistical analysis, and spatial autocorrelation to assess how earthquake and
typhoons affect landscape patterns. It addresses variations of the Chenyulan watershed in Nantou County, near the earthquake’s
epicenter and crossed by Typhoon Toraji. The subsequent disturbances have gradually changed landscape of the Chenyulan watershed.
Disturbances of various types, sizes, and intensities, following various tracks, have various effects on the landscape patterns
and variations of the Chenyulan watershed. The landscape metrics that are obtained by multivariate statistical analyses showed
that the disturbances produced variously fragmented patches, interspersed with other patches and isolated from patches of
the same type across the entire Chenyulan watershed. The disturbances also affected the isolation, size, and shape-complexity
of patches at the landscape and class levels. The disturbances at the class level more strongly affected spatial variations
in the landscape as well as patterns of grasslands and bare land, than variations in the watershed farmland and forest. Moreover,
the earthquake with high magnitude was a starter to create these landscape variations in space in the Chenyulan watershed.
The cumulative impacts of the disturbances on the watershed landscape pattern had existed, especially landslides and grassland
in the study area, but were not always evident in space and time in landscape and other class levels. 相似文献
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Key Elements of Landscape Pattern Measures 总被引:9,自引:0,他引:9
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《资源开发与市场》2016,(3)
盆地包括以山地、高原为主的盆边区域和以平原或少量缓坡、丘峰分布为主的盆底区域。云南是个多山的省份,人口主要分布在地势低平的盆地区域尤其是盆底区域,盆地人口密集,是云南省主要的经济文化发展要地和农业生产基地。选取生态意义较明显的景观格局特征指数,对滇东南峰林峰丛区主要盆地土地利用结构及生态环境效应进行分析。结果表明:依据盆地的地理环境特征不同,盆地景观系统可分为平坝区、盆地边缘山麓带和盆地边缘山坡带三种景观亚系统类型,每一种景观系统都有多种景观要素构成,且因所处地貌不同而差异显著。盆地土地利用结构中,耕地景观所占的比例最大,平均值最高,其次是森林、草地和人造地表。八宝、广南、丘北、曰者和珠琳盆地景观优势度指数大,景观破碎度指数小,盆地生态环境质量高。景观格局指数与生态环境之间相关性较大,其中景观类型多样性与生态环境指数呈正相关,景观破碎度与生态环境指数呈负相关,景观格局的空间特征对当地的生态环境影响较大。 相似文献
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基于RS和GIS的技术方法,运用景观格局指数对赛里木湖流域近25a来的景观格局变化综合分析。结果表明:1986-2010年,赛里木湖流域疏林地、灌木林地和中覆盖度草地面积增加,有林地、高覆盖度草地面积减小。整体上,景观斑块总数增加,景观破碎化指数、景观类型形状指数和景观多样性指数升高,均匀度指数有所减少。由此可以看出,该区域内由于自然或人为因素干扰所导致的景观斑块类型逐渐变得复杂,景观遭到破坏,土地利用向着多样化和非均匀化的方向发展,景观斑块分布变得很不均匀。 相似文献
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Landscape spatial patterns have increasingly been considered to be essential for environmental planning and resources management.
In this study, we proposed a hierarchical approach for landscape classification and evaluation by characterizing landscape
spatial patterns across different hierarchical levels. The case study site is the Red Hills region of northern Florida and
southwestern Georgia, well known for its biodiversity, historic resources, and scenic beauty. We used one Landsat Enhanced
Thematic Mapper image to extract land-use/-cover information. Then, we employed principal-component analysis to help identify
key class-level landscape metrics for forests at different hierarchical levels, namely, open pine, upland pine, and forest
as a whole. We found that the key class-level landscape metrics varied across different hierarchical levels. Compared with
forest as a whole, open pine forest is much more fragmented. The landscape metric, such as CONTIG_MN, which measures whether
pine patches are contiguous or not, is more important to characterize the spatial pattern of pine forest than to forest as
a whole. This suggests that different metric sets should be used to characterize landscape patterns at different hierarchical
levels. We further used these key metrics, along with the total class area, to classify and evaluate subwatersheds through
cluster analysis. This study demonstrates a promising approach that can be used to integrate spatial patterns and processes
for hierarchical forest landscape planning and management. 相似文献
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伊犁河谷景观格局变化分析 总被引:2,自引:0,他引:2
景观生态学是宏观生态研究的一个新的领域.景观动态变化研究,是目前景观生态学中的一个研究热点.基于伊犁河谷2000年、2005年夏季有效时相Landsat TM/ETM 遥感影像资料,综合运用遥感与GIS技术,通过采用分维数,多样性指数,破碎度指数和边界密度等指数,分析了伊犁河谷景观动态变化.研究结果表明:①草地、水域和林地面积大幅度减少,耕地和城乡居民工矿交通用地猛增,城市化进程加快;②伊犁河谷斑块数目增多,景观边缘密度增加,景观破碎度增大,伊犁河谷景观异质性和景观形状的复杂性程度略微提升;③景观基质依然为草地,草地破碎度稍增,草地的多样性和异质性下降;④耕地的斑块数减少而斑块面积增大,破碎化程度降低,耕地的稳定性加强. 相似文献
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水西景区景观格局及土地利用结构分析 总被引:2,自引:0,他引:2
景观格局与土地利用空间结构密切相关.运用景观多样性、优势度、均匀度和破碎度等景观生态学指标,对水西景区景观格局及其用地现状进行了分析.结果表明:水西用地类型多样性较高,以林地占优势,林地破碎度低,森林景观较完整,但空闲地和建筑用地受人类活动干扰大,破碎度高,在一定程度上影响了水西的景观格局. 相似文献
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利用两个时期的Landsat TM/ETM遥感影像,结合RS和GIS技术,直接从遥感图像上获得景观格局指数,对安徽省合肥市的景观格局进行了分析。揭示在快速经济发展和不断加快的城市化进程中,合肥市景观形状指数、分形维数和破碎度指数的不同变化趋势。与传统方法相比,该方法具有快速、准确、节省费用、简单易行的特点,有利于对景观格局变化进行动态监测。 相似文献
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Aarin Teague Philip B. Bedient Birnur Guven 《Journal of the American Water Resources Association》2011,47(3):620-634
Teague, Aarin, Philip B. Bedient, and Birnur Guven, 2011. Targeted Application of Seasonal Load Duration Curves Using Multivariate Analysis in Two Watersheds Flowing Into Lake Houston. Journal of the American Water Resources Association (JAWRA) 47(3):620‐634. DOI: 10.1111/j.1752‐1688.2011.00529.x Abstract: Water quality is a problem in Lake Houston, the primary source of drinking water for the City of Houston, Texas, due to pollutant loads coming from the influent watersheds, including Spring Creek and Cypress Creek. Statistical analysis of the historic water quality data was developed to understand the source characterization and seasonality of the watershed. Multivariate analysis including principal component, cluster, and discriminant analysis provided a custom seasonal assessment of the watersheds so that loading curves may be targeted for season specific pollutant source characterization. The load duration curves have been analyzed using data collected by the U.S. Geologic Survey with corresponding City of Houston water quality data at the sites to characterize the behavior of the pollutant sources and watersheds. Custom seasons were determined for Spring Creek and Cypress Creek watersheds and pollutant source characterization compared between the seasons and watersheds. 相似文献
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Hakan Alphan 《Environmental management》2013,51(3):541-554
The aim of this study is (1) to quantify landscape changes in the easternmost Mediterranean deltas using bi-temporal binary change detection approach and (2) to analyze relationships between conservation/management designations and various categories of change that indicate type, degree and severity of human impact. For this purpose, image differencing and ratioing were applied to Landsat TM images of 1984 and 2006. A total of 136 candidate change images including normalized difference vegetation index (NDVI) and principal component analysis (PCA) difference images were tested to understand performance of bi-temporal pre-classification analysis procedures in the Mediterranean delta ecosystems. Results showed that visible image algebra provided high accuracies than did NDVI and PCA differencing. On the other hand, Band 5 differencing had one of the lowest change detection performances. Seven superclasses of change were identified using from/to change categories between the earlier and later dates. These classes were used to understand spatial character of anthropogenic impacts in the study area and derive qualitative and quantitative change information within and outside of the conservation/management areas. Change analysis indicated that natural site and wildlife reserve designations fell short of protecting sand dunes from agricultural expansion in the west. East of the study area, however, was exposed to least human impact owing to the fact that nature conservation status kept human interference at a minimum. Implications of these changes were discussed and solutions were proposed to deal with management problems leading to environmental change. 相似文献
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