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青海湖流域景观格局空间粒度效应分析 总被引：1，自引：0，他引：1
流域是生态系统的基本单元和重要空间尺度单元,流域尺度景观格局分析的科学性很大程度上依赖于最佳空间粒度的选取是否准确。选择青海湖流域为研究区,基于卫星遥感数据资料,利用面向对象分类方法,解译获得流域景观数据,通过重采样得到不同空间粒度的流域景观数据,计算得到不同景观格局指数并绘制各指数与空间粒度之间的关系曲线,识别景观格局指数的尺度效应,评估空间粒度增加而引起的景观格局指数信息损失量,确定流域尺度景观格局分析的最佳空间粒度。结果表明:流域景观格局指数随着空间粒度增大变化显著,但规律不同;综合景观指数的空间粒度效应和信息损失量变化特征,流域景观格局分析的最佳空间粒度选择以90 m为最佳。 相似文献
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为了研究近30年内西辽河流域湿地景观格局变化特征,本文基于1985年TM数据、2000年ETM数据和2015年OLI数据,利用景观格局软件Fragstats4.2,选取了8个景观格局指标,进而分析30年来西辽河湿地景观格局变化情况,结果表明:1)各湿地类型总斑块数和斑块密度呈下降趋势,湿地逐渐转化为建设用地和非建设用地,湿地主导类型变为人工湿地; 2)研究区湿地破碎化虽然有所减弱,但景观格局变化依然明显; 3)湿地大面积减少,湿地多样性大大降低,空间连通性较优,景观类型趋于单一化。 相似文献
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空间分布模式是否保持一致是土地利用数据综合质量评价的一项重要内容。针对当前的研究缺少量化分析和位置表达的现状,提出了一种新的空间数据特有的自相关性评价方法。首先利用语义距离建立空间权重矩阵,随后通过莫兰指数（Moran’s I）计算数据处理前后全局和局部自相关度,最后利用莫兰（Moran）散点图和空间关联的局部指标（local indicators of spatial association,LISA）集聚图相结合的方法对综合前后的土地利用分布模式进行可视化对比。相较传统评价方法,所提方法顾及数据语义关系,计算可量化聚集程度,以直观可视化方法对比展示,更好地对土地利用数据在综合前后的全局空间分布模式一致性进行了评价。认知实验结果符合人类认知,表明所提方法切实有效。 相似文献
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为了实现对景观连续变化特征与连接特征的描述,并保持与斑块镶嵌特征的空间尺度一致性,该文利用高分辨率遥感数据,采用面向对象分割方法,建立基于Delaunay-Voronoi原理的景观格局定量描述模型,统一表达景观格局的镶嵌、连续以及连接特征;并将此图像分割方法的结果与像素聚合方法的结果进行对比。结果表明:1面向对象的图像分割方法能够更好地保存对景观格局提取至关重要的微细景观特征,并在尺度上推过程中延缓这些细微特征消失;2基于Delaunay-Voronoi数据结构的景观格局模型有利于面向对象影像分析的景观镶嵌、连续和连接特征的混合及其多尺度表达,更适用于高分辨率遥感景观格局信息提取。 相似文献
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抚仙湖流域土地利用格局与水质变化关系 总被引：1，自引：0，他引：1
《国土资源遥感》2016,(1)
抚仙湖是我国水质较好的大型淡水湖泊之一,其总体水质为Ⅰ类。近年来由于流域内开发强度增加,水体水质呈现下降的趋势。为探究流域土地利用变化可能对湖泊水质产生的影响,利用1992—2010年的Landsat TM和ETM+数据,结合GIS技术和统计学方法,分析了流域内土地利用及景观格局变化与湖泊水质的响应关系。研究结果显示:抚仙湖水体面积缩小,流域内林地和耕地面积总体呈减小趋势,与水质污染指数变化呈显著负相关;交通运输用地和建设用地增长迅速,与水质污染指数响应呈显著正相关;景观斑块数目、形状指数等景观格局指数增加,流域景观格局破碎化加重,与水质污染指数变化呈显著正相关;土地利用及景观格局指数可以作为研究抚仙湖水质变化的重要指标。 相似文献
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黄土高原上黄小流域土地利用景观格局分析 总被引：1，自引：0，他引：1
景观格局是景观生态学研究的三大内容之一,是研究景观过程与景观功能的基础。本文以黄土高原上黄小流域1982年~2008年的6期土地利用图为数据基础,选取反映研究区景观格局特征的景观指数,运用所选景观指数对研究区土地利用的空间格局进行定量研究并分析了其变化的驱动因素。结果表明:利用主成分分析法选择的7个景观指数可以有效地反映研究区土地利用景观格局的基本特征。 相似文献
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以淮南煤矿区泥河小流域1987、1994、2000、2006、2009、2013、2017年7期多源遥感影像为数据源，结合纹理和光谱特征，利用支持向量机（SVM）对遥感影像进行分类，在此基础上分析了煤炭开采对泥河小流域近30年土地利用和景观格局变化的影响。结果表明：煤炭开采影响下流域的土地利用变化最显著的特征是耕地和建设用地的相互转变及耕地向塌陷水体的转变，30年间塌陷水体和建设用地分别增加了2 281.05、14 741.73 hm2，耕地减少了15 044.67 hm2。采煤驱动下，流域景观格局变化特征体现在以2006年为转折点，前期呈现破碎化、不规则化、异质化和低连通性变化的特征，之后呈现连续化、规则化、均衡化及高连通性变化的特征。建设用地、耕地和塌陷水体经历了不断破碎化到景观逐渐完善的过程；耕地、建设用地和自然水体斑块形状较为复杂；耕地优势性逐渐减弱，最大斑块指数由79.706 0降为38.745 5，塌陷水体和建设用地的优势性增强。 相似文献
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RS和GIS支持下的盐池县生态景观格局动态变化研究 总被引：2，自引：1，他引：2
基于遥感（RS）和地理信息系统（GIS）技术，以Landsat TM/ETM图像为基本数据源，综合运用景观生态学理论和方法，对我国典型农牧交错生态脆弱区宁夏盐池县1991~2000年生态景观格局动态变化进行了研究。结果表明： 盐池县各景观类型都发生了很大程度的消长变化，景观格局处于快速调整和不稳定发展阶段，但生态景观基质还是草地，景观格局始终呈农牧交错结构。 相似文献
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基于GIS的长白山景观格局演化信息图谱分析 总被引：1，自引：0，他引：1
景观格局是若干生态系统的综合体,受地貌、气候和其他外界多种因素的干扰,是模拟和预测地理要素变化趋势的基础。地学信息图谱理论为景观格局研究提供新的方法。基于RS和GIS技术,分析了20世纪70年代后期以来长白山地区景观格局图谱的时空变化规律。利用1977年MSS、1985年、1999年TM影像时间系列的遥感数据,建立空间信息库,选取景观/斑块类型面积、斑块所占景观面积的比例、平均斑块面积、斑块个数、破碎度指数、分维数、优势度指数等指标,对长白山景观空间格局的动态演变进行了分析。分析了长白山地区近30年来的景观结构变化,建立长白山景观格局演化的信息图谱。景观格局与过程的变化表明,人为活动对景观格局产生的影响,已成为景观格局变化的主要驱动因子。 相似文献
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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
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As one of the vital research highlights of global land use and cover change, oasis change and its interaction with landscape pattern have been regarded as an important content of regional environmental change research in arid areas. Jinta oasis, a typical agricultural oasis characterized by its dramatic exploitation and use of water and land resources in Hexi corridor, northwest arid region in China, was selected as a case to study the spatiotemporal oasis change and its effects on oasis landscape pattern. Based on integration of Keyhole satellite photographs, KATE-200 photographs, Landsat MSS, TM and ETM+ images, we evaluated and analyzed the status, trend and spatial pattern change of Jinta oasis and the characteristics of landscape pattern change by a set of mathematical models and combined this information with landscape metrics and community surveys. During the period of 1963a–2010a, Jinta oasis expanded gradually with an area increase of 219.15 km2, and the conversion between oasis and desert was frequent with a state of “imbalance–balance–extreme imbalance conditions”. Moreover, most of the changes took place in the ecotone between oasis and desert and the interior of oasis due to the reclamation of abandoned land, such as Yangjingziwan and Xiba townships. Furthermore, the area, size and spatial distribution of oasis were influenced by human activities and resulted in fundamental changes of oasis landscape pattern. The fractal characteristics, dispersion degree and fragmentation of Jinta oasis decreased and the oasis landscape tended to be simple and uniform. Oasis change trajectories and its landscape pattern were mainly influenced by water resource utilization, policies (especially land policies), demographic factors, technological advancements, as well as regional economic development. We found that time series analysis of multi-source remote sensing images and the application of an oasis change model provided a useful approach to monitor oasis change over a long-term period in arid area. It is recommended that the government and farmers should pay more attention to the fragility of the natural system and the government should enhance the leading role of environmental considerations in the development process of oasis change, particularly with respect to the utilization of the limited water and land resources in arid China. 相似文献
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Urbanization is a natural and social process involving simultaneous changes to the Earth’s land systems, energy flow, demographics, and the economy. Understanding the spatiotemporal pattern of urbanization is increasingly important for policy formulation, decision making, and natural resource management. A combination of satellite remote sensing and patch-based models has been widely adopted to characterize landscape changes at various spatial and temporal scales. Nevertheless, the validity of this type of framework in identifying long-term changes, especially subtle or gradual land modifications is seriously challenged. In this paper, we integrate annual image time series, continuous spatial indices, and non-parametric trend analysis into a spatiotemporal study of landscape dynamics over the Phoenix metropolitan area from 1991 to 2010. We harness local indicators of spatial dependence and modified Mann-Kendall test to describe the monotonic trends in the quantity and spatial arrangement of two important land use land cover types: vegetation and built-up areas. Results suggest that declines in vegetation and increases in built-up areas are the two prevalent types of changes across the region. Vegetation increases mostly occur at the outskirts where new residential areas are developed from natural desert. A sizable proportion of vegetation declines and built-up increases are seen in the central and southeast part. Extensive land conversion from agricultural fields into urban land use is one important driver of vegetation declines. The xeriscaping practice also contributes to part of vegetation loss and an increasingly heterogeneous landscape. The quantitative framework proposed in this study provides a pathway to effective landscape mapping and change monitoring from a spatial statistical perspective. 相似文献
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由于传统二维景观格局指数未考虑地形特征对景观格局指数的影响,为进一步研究地形结构对景观格局指数的影响,以重庆主城区为研究对象,利用ENVI5.2、ArcGIS10.5、Fragstats4.2平台,对重庆主城区不同城市化阶段的Landsat影像数据进行土地利用变化和三维景观格局分析。结果表明,2008-2018年研究区土地利用面积发生了较大变化,表现为林地和建设用地增加,耕地减少,湖泊与河流面积变化不大;景观格局变化主要表现为景观受人类干扰较强,随着城镇规划越来越合理,景观破碎度减少,景观异质性降低。通过对比二维景观格局指数发现,三维景观格局指数更能反映研究区的景观格局。 相似文献
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Evaluating Local Non-Stationarity when Considering the Spatial Variation of Large-scale Autocorrelation 总被引：1，自引：0，他引：1
Multi‐scale effects of spatial autocorrelation may be present in datasets. Given the importance of detecting local non‐stationarity in many theoretical as well as applied studies, it is necessary to “remove” the impact of large‐scale autocorrelation before common techniques for local pattern analysis are applied. It is proposed in this paper to employ the regionalized range to define spatially varying sub‐regions within which the impact of large‐scale autocorrelation is minimized and the local patterns can be investigated. A case study is conducted on crime data to detect crime hot spots and cold spots in San Antonio, Texas. The results confirm the necessity of treating the non‐stationarity of large‐scale spatial autocorrelation prior to any action aiming at detecting local autocorrelation. 相似文献
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LI Jianping GAO Feng ZHANG Bai 《地球空间信息科学学报》2007,10(2):128-132
By using remote sensing images from three periods (1980, 1995, 2000) and with the support of GIS and RS, the spatial information of landscape elements of Jilin Province from 1980 to 2000 was interpreted and extracted. Using models of landscape indices such as diversity, fragmentation, and mean patch fractal dimension, dynamic spatio-temporal changes of landscape patterns of the province were analyzed. The results: ① cropland and forestland were the main landscape types, and forestland became a landscape matrix; ② in the study area, landscapes were distributed unevenly, and there was low heterogeneity, a simple ecosystem structure and a tendency of irrational landscape patterns. There were also simple spatial shapes of patches and strong self-similarities, and in terms of dynamic change analysis, patch shapes tended to be more simple; ③ from 1980 to 2000, holistic landscape fragmentation was low and changed slightly. As far as landscape elements were concerned, the fragmentation of grassland, water area, land for residential area and factory facilities was relatively low; land distribution for residential areas and factory facilities was dispersed; and cropland and forestland were most concentrated-an indication that the trend will continue. Comprehensive effects among human activity, local policy, regional climate and environmental change led to the results. 相似文献
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本文以河南省漯河市为例,以遥感解译的漯河市近40年来土地利用数据为基础,运用GIS叠置分析、土地利用转移矩阵等空间分析方法,结合景观格局指标,研究其改革开放以来土地利用及景观格局变化特征,为优化土地资源配置及科学的城市规划提供依据。结果表明:(1)1980年至2015年间漯河城镇用地面积呈显著增加趋势,扩张主要占用耕地;(2)林地和农村居民点用地总体呈增加趋势,2000年来其他建设用地面积迅速增加;(3)漯河市各景观类型总体呈平衡发展态势,耕地优势度有所下降,建设用地优势度不断上升;(4)人口增长与经济发展、交通条件改善及政府政策变动是影响漯河市土地利用变化和景观格局演变的主要因素。 相似文献