滇西北高原湿地区土地利用变化特征

湿地景观格局的动态变化与区域土地利用/覆盖格局的变化有着十分紧密的联系。以纳帕海、碧塔海和属都湖三块高原湿地所在的云南省香格里拉县建塘镇为例,在遥感和GIS技术的支持下,对该区域1974、1987和2000三期Landsat TM(ETM)影像进行了解译,分析了26 a间的土地利用/覆盖变化规律,并结合景观格局动态分析的方法,借助FRAGSTATS软件定量分析了该区景观格局特征及其动态变化。结果表明:该区土地利用/覆盖状况变化显著,主要土地利用/覆盖类型有林地以822 hm2/a的速度在大面积减少,并主要转为灌木林地,使得后者在26 a间扩大高达17倍,变化幅度最大。建设用地和耕地的面积分别扩大了6倍和2倍,而草地和雪地面积持续减少。相应地,该区景观格局定量分析显示,有林地的斑块密度增大而平均斑块面积减小迅速,呈破碎化趋势,灌木林地的斑块密度、平均斑块面积均增加,草地则与之相反均减小,耕地的斑块密度降低而平均斑块面积增加,在不断融合成大斑块,其余各景观单元斑块密度增大平均斑块面积减小,同时各斑块几何形状在1987年变化最剧烈,景观格局趋于复杂。     

Evaluation of forest cover change using remote sensing techniques and landscape metrics in Moncayo Natural Park (Spain)

Monitoring the change in land cover in natural places, such as ecotones, has become an important tool for forest management, especially in protected areas. The present work analyses the spatial and temporal changes in forest cover in Moncayo Natural Park (Spain) from 1987 to 2010 using remote sensing techniques, geographical information systems (GIS) and quantitative indices of landscape ecology. Four Landsat images were used to map nine representative land cover categories in this preserved area in both years. The overall classification accuracies in land cover cartographies in 1987 and 2010 were 87.65% and 84.56%, respectively. Landscape metrics obtained at the landscape level show an increase in fragmentation and, as a result, an increase in landscape spatial diversity. Focusing on the class level, the results show a forest expansion of sessile oaks (Quercus petraea) and beech forest (Fagus sylvatica), two important bioclimatic indicators in this natural park, because they are the southernmost locations for these species in Europe. The decrease of mainly introduced pine forest and the transformation of mixed shrub areas into natural forested areas explain the aforementioned increase in fragmentation. These results are in agreement with the strategies for nature conservation designed by forest managers during the period evaluated.     

兰州市南北两山绿地景观格局分析

将景观生态学的理论与兰州南北两山环境绿化工程的实际相结合,运用景观格局分析方法、GIS（ARC/INFO）和数理统计等多种方法,在绿化工程景观评价指标研究的基础上,研究了兰州南北两山环境绿化工程区域按坡度分布的景观格局特征。结果表明：兰州市南北两山各个分级坡度上景观多样性均不高,除0°~9°上的大于1外,其余的均小于1。各个分级坡度上景观格局指数、各指标的组合状况值、景观格局综合指标值总体上符合随坡度增加而减小的趋势。但40°~49°的景观格局指数、各指标的组合状况值、景观格局综合指标值比30°~39°的景观格局指数、各指标的组合状况值、景观格局综合指标值稍大,这是因为40°~49°上的林地和农地的斑块数较30°~39°的多,且占本坡度所有土地面积的比例也大于30°~39°的。兰州市南北两山各个分级坡度上景观格局指数、各指标的组合状况值、景观格局综合指标值在0°~9°上均明显高于其他坡度地区的。     

GIS-based Analysis of Temporal Evolution of Rural Landscape: A Case Study in Southern Italy

The apparent features of a rural landscape are the final result of the interaction among several natural and anthropic factors. The analysis of a landscape, as well as the identification of its best management strategies, can be improved when useful information about its modifications along a wide time period is available, so as to assess the effect of the transformations that have taken place there. The implementation within a geographic information system (GIS) of geographical information derived from ancient historical maps, combined with modern digital cartography and recent remote sensing images may provide a very powerful tool for a better-informed analysis and targeted decision-making strategies about the most appropriate rural landscape planning. With the purpose to detect the land use changes in a typical rural landscape in the Basilicata Region (Southern Italy), spatial analysis using free and open-source GIS tools, in which data covering a period of about two centuries, from 1829 to 2017, were implemented. This multi-temporal analysis was carried out to investigate the landscape structure transformations through the assessment of land use change and the implementation of a methodology for the identification of areas in which there has been a natural evolution of the rural landscape. Then, using landscape metrics and spatial analysis tools, some areas in which the landscape has naturally evolved without any anthropic intervention during these 188 years have been identified, and changes occurred on the rural landscape were assessed quantitatively.

     

A Landscape Ecology Approach to Assessing Development Impacts in the Tropics: A Geothermal Energy Example in Hawaii

Geographic information systems (GIS) are increasingly being used in environmental impact assessments (EIA) because GIS is useful for analysing spatial impacts of various development scenarios. Spatially representing these impacts provides another tool for landscape ecology in environmental and geographical investigations by facilitating analysis of the effects of landscape pattern on ecological processes and examining change over time. Landscape ecological principles are applied in this study to a hypothetical geothermal development project on the Island of Hawaii. Some common landscape pattern metrics were used to analyse dispersed versus condensed development scenarios and their effect on landscape pattern. Indices of fragmentation and patch shape did not appreciably change with additional development. The amount of forest to open edge, however, greatly increased with the dispersed development scenario. In addition, landscape metrics showed that a human disturbance had a greater simplifying effect on patch shape and also increased fragmentation than a natural disturbance. The use of these landscape pattern metrics can advance the methodology of applying GIS to EIA.     

Monitoring land changes in an urban area using satellite imagery,GIS and landscape metrics

Monitoring land changes is an important activity in landscape planning and resource management. In this study, we analyze urban land changes in Atlanta metropolitan area through the combined use of satellite imagery, geographic information systems (GIS), and landscape metrics. The study site is a fast-growing large metropolis in the United States, which contains a mosaic of complex landscape types. Our method consisted of two major components: remote sensing-based land classification and GIS-based land change analysis. Specifically, we adopted a stratified image classification strategy combined with a GIS-based spatial reclassification procedure to map land classes from Landsat Thematic Mapper (TM) scenes acquired in two different years. Then, we analyzed the spatial variation and expansion of urban land changes across the entire metropolitan area through post classification change detection and a variety of GIS-based operations. We further examined the size, pattern, and nature of land changes using landscape metrics to examine the size, pattern, and nature of land changes. This study has demonstrated the usefulness of integrating remote sensing with GIS and landscape metrics in land change analysis that allows the characterization of spatial patterns and helps reveal the underlying processes of urban land changes. Our results indicate a transition of urbanization patterns in the study site with a limited outward expansion despite the dominant suburbanization process.     

Evaluating the effects of land‐use development policies on ex‐urban forest cover: An integrated agent‐based GIS approach

We use a GIS‐based agent‐based model (ABM), named dynamic ecological exurban development (DEED), with spatial data in hypothetical scenarios to evaluate the individual and interacting effects of lot‐size zoning and municipal land‐acquisition strategies on possible forest‐cover outcomes in Scio Township, a municipality in Southeastern Michigan. Agent types, characteristics, behavioural methods, and landscape perceptions (i.e. landscape aesthetics) are empirically informed using survey data, spatial analyses, and a USDA methodology for mapping landscape aesthetic quality. Results from our scenario experiments computationally verified literature that show large lot‐size zoning policies lead to greater sprawl, and large lot‐size zoning policies can lead to increased forest cover, although we found this effect to be small relative to municipal land acquisition. The return on land acquisition for forest conservation was strongly affected by the location strategy used to select parcels for conservation. Furthermore, the location strategy for forest conservation land acquisition was more effective at increasing aggregate forest levels than the independent zoning policies, the quantity of area acquired for forest conservation, and any combination of the two. The results using an integrated GIS and ABM framework for evaluating land‐use development policies on forest cover provide additional insight into how these types of policies may act out over time and what aspects of the policies were more influential towards the goal of maximising forest cover.     

榆林市农业景观格局变化研究

根据1986年和2000年两期TM影像资料和其他辅助资料, 运用人机交互解译方法以及地理信息系统的空间分析和数理统计功能, 分析了榆林市农业景观格局变化, 包括土地利用数量变化、变化速度和区域差异等特征, 以及各景观类型之间的转化情况, 并对景观格局变化进行了定量分析。结果表明: 14a间, 榆林市未利用地减少1305.56km², 其中主要是沙地减少; 耕地、林地、草地分别增加567.11km²、99.6km²和616.79km²; 未利用地和建设用地的变化率最大, 分别为-22.11%和18.18%; 土地利用变化存在明显的区域差异; 各类型间的转化突出表现为未利用地向草地转化, 草地向林地和耕地转化。榆林市近十几年景观类型发生了明显转换, 土地整治取得显著成绩。     

Paraguay's Atlantic Forest cover loss – Satellite-based change detection and fragmentation analysis between 2003 and 2013

The subtropical Atlantic Forest is a highly diverse ecosystem in South America and one of the most endangered rain forests in the world. The present study focuses specifically on the Paraguayan part of the tri-national Atlantic Forest. Over the last decades, the Paraguayan Atlantic Forest presented one of the highest deforestation rates in the world, and today, only a small share remains. Hence, forest loss in Paraguay's Atlantic Forest was detected and analysed through remote sensing and GIS methodologies based on Landsat images obtained in 2003 and 2013. The objective of this study was to examine the spatial impact of forest loss in Paraguay's Atlantic Forest over the past decade with a special focus on biodiversity conservation. Classifications results obtained overall accuracies above 83% and revealed that over 6000 km² of forest was cleared during the study period. The forest landscape and its fragmentation level were characterised through a set of landscape metrics, in particular the proximity analysis which support the identification of forest priority areas for nature conservation and potential biological corridors. In summary, the study revealed that deforestation and fragmentation of the Atlantic Forest area continued, but at a slower pace than that in the previous decade. Protected areas were conserved very effectively; however, forest core areas without any protection status require further attention. Intact forest patches and their connectivity are a crucial prerequisite to biodiversity conservation in a highly fragmented forest area. The combination of different remote sensing and GIS methods provides valuable information for sustainable forest management in the region.     

基于RS和GIS的西双版纳土地覆被动态变化

人口增加、经济发展导致滇南热带地区西双版纳土地利用/土地覆被发生显著变化,这些变化对该区的生态环境及生物多样性保护有着重要影响。基于RS和GIS方法,通过对1976、1988和2003年三个时期遥感影像解译分析,试图了解西双版纳近27 a间土地利用/土地覆被时空变化特征及影响因素。结果表明,近27 a间有林地在西双版纳分布最广、占绝对优势,其中以亚热带常绿阔叶林面积最大;但在研究时段内,有林地面积不断减少、呈现破碎化,尤其是热带季节雨林、山地雨林面积减少最为明显和破碎化最为严重。相应,橡胶园、灌木林面积不断扩大并聚集成片,其中橡胶园在1988~2003年间是面积增长最快、最多的地类,其面积扩张主要来源于对热带季节雨林的砍伐。轮歇地面积在1976~1988年是所有地类中增长最快、最多的,在1988~2003年由于向橡胶园转变而大幅度减小。粗放式的刀耕火种和橡胶种植园的不断扩大是主导本区土地利用/土地覆被变化的主要因素,土地利用变化导致了本区生态环境的退化和生物多样性的丢失。     

新疆南疆地区土地利用变化及其生态效应

基于GIS平台,以新疆各县市统计数据为基础,对南疆土地利用变化特征及其生态效应进行分析。分析得出:①近12 a间耕地、园地、林地、水域及建设用地面积增加,而草地和未利用土地面积减少。12 a间土地利用综合动态度为0.88%,园地、建设用地和耕地的年变化率较大;林地、草地、水域和未利用土地的较低。土地利用变化存在明显的区域差异,巴州除未利用土地以外,土地利用类型的变幅均大于全区相应土地利用类型的变幅,和田所有土地利用类型的变幅均小于全区的变幅。②绿洲耕地面积的扩展以牺牲自然荒漠植被为代价,致使绿洲生态问题日益突出,主要表现为植被退化、沙漠化、生境质量下降、土壤盐渍化和水质恶化等。     

Trends of tropical deforestation in Southeast Mexico

We assessed deforestation in Southeast Mexico (a surface area of 29 000 km² in seven states) through the comparison of land use/land cover maps at a scale of 1:250 000. This facilitated mapping of the land use/land cover change (LULCC) processes and calculation of the rates of change and the change matrix for the period 1978–2000. An original method was used to assess the accuracy of the LULCC map. The verification sites were selected through a stratified random sampling and were corroborated with aerial photographs for 1978 and 2000. Error matrices were elaborated using both hard and fuzzy set approaches in order to take into account the errors related to generalization of the map in fragmented landscapes. The results showed an average annual deforestation rate of 1.1 per cent which represents an average annual loss of 190 000 ha of forest, or an estimated total reduction of 4.2 million ha over 22 years. Furthermore, deforestation processes are concentrated in some areas such as Yucatan and Chiapas states, which registered major forest conversions to grassland and slash‐burning. The overall accuracy of the LULCC map, assessed with hard and fuzzy set approaches, was 72 per cent and 88 per cent respectively.     

1989-2003年中国北方土地覆被变化

The 13 provinces （autonomous regions and municipalities） in northern China are located in latitude 31°-54°N and longitude 73°-136°E including Beijing, Tianjin, Hebei, Shanxi, Inner Mongolia, Jilin, Liaoning, Heilongjiang, Shaanxi, Gansu, Ningxia, Qinghai, and Xinjiang, where environments are fragile. In recent years, the eco-environmental problems such as vegetation destruction, desertification and soil erosion etc. become serious because of climate change and unreasonable human activities. In this paper, landscape pattern and its evolution in northern China from 1989 to 2003 was investigated by the combined use of RS and GIS based on the basic theory and method of landscape ecology. Land use/cover maps of the study area in 1989, 1999 and 2003 were produced by using 1 km monthly NOAA Advanced Very High Resolution Radiometer （AVHRR） and SPOTNGT Normalized Difference Vegetation Index （NDVI） dataset from national climate bureau of China which were geo-registered to Lambert azimuthal equal-area map projection and were used in the paper. Landscape evolution in the area over the study period was investigated by two methods： （a） the changes of various landscape metrics were analyzed using the landscape structure analysis program FRAGSTATS; （b） the transition matrix of landscape patch types was calculated with the help of the RS and GIS software. The results showed that from 1989 to 2003, the landscape within the study area had undertaken a complicated evolution in landscape structure and composition. The diversity index and evenness index increased during the period, which means that the landscape pattern tended to be diversified and even. The fragmentation index of grassland, forestland and water areas also increased significantly. This showed that the distribution and structure of forestland, grassland and water areas had been changed greatly during the period, especially grassland which became more and more fragmentized, and its fragmentation index increased from 19.23% to 88.72%. The transi     

东洞庭湿地植被格局变化及其影响因素

东洞庭湖(也称东洞庭)湿地植被格局的变化特征及其影响因素的分析是该地区湿地植被保护与恢复策略制定的基础。基于美国陆地资源卫星Landsat TM/ETM+数据,应用决策树分类法分别提取东洞庭湖1999年、2002年、2006年三个时期湿地景观信息,通过转移矩阵法和质心迁移法对植被的时空演变分析。结果表明:(1)1993～2002年东洞庭湖芦苇、林地、苔草滩地面积均有所增加,芦苇增长速度最快,年均增长面积为28.93km²;2002～2006年林地面积迅速增加,年均增长面积为29.655km²,苔草面积有所减少,芦苇面积保持基本稳定;(2)东洞庭湖湿地植被质心呈现从林地—芦苇—苔草逐层靠近湖心的分布特点,1993～2006年三种植被类型的质心均不断向湖心迁移,其中以林地与芦苇的变迁更为显著。     

南京城市森林景观格局特征与空间结构优化

城市森林研究是一个新兴的研究领域, 城市森林的景观生态学研究是城市森林研究的必然发展趋势和重要内容。首先根据景观生态分类法的思想和原则, 将城市森林景观分为2 个类型4 个亚型, 然后综合运用RS 和GIS 技术进行南京城市森林景观类型空间信息调查, 获取城市森林景观类型分布图及类型空间属性数据。在此基础上, 以定量和定性相结合的方法分析城市森林景观格局特征, 并提出城市森林景观空间结构优化的措施和建议。研究认为, 南京城市森林景观具有总覆盖度适宜, 空间分布的区域差异极为突出, 大型半自然和近自然 林斑块是景观主体, 景观生态系统的形成、分布和类型分异与自然环境的地域分异密切相关, 人类对景观干扰作用强等特点, 而因地制宜的构建基于" 集中与分散相结合原则" 的总体结构优化模式是南京城市森林景观发展的主导方向, 设计不同尺度和等级规模的景观廊道是景观建设的主要任务, 加强生态敏感部位景观斑块建设是关键措施。     

Integration of multi-source remote sensing data for land cover change detection

The objective of this study is to develop a methodology to integrate multi-source remote sensing data into a homogeneous time series of land cover maps in order to carry out change detection. We developed a method to increase the comparability between land cover maps coming from panchromatic aerial photographs and SPOT XS (multi-spectral) data by equalizing their levels of thematic content and spatial details. The methodology was based on the hypotheses that: (1) map generalization can improve the integration of data for change detection purpose, and (2) the spatial structure of a land cover map, as measured by a set of landscape metrics, is an indicator of the level of generalization of that map. Firstly, the methodology for data integration was developed by using land cover maps generated from near-synchronous data. Results revealed that, by controlling successively the parameters that influence the level of map generalization, the percentage of agreement between the near-synchronous land cover maps can be increased from 42% to 93%. The computation of five landscape metrics for a set of generalized land cover maps and for the target map allowed us to optimize the level of generalization by measuring the similarity in landscape pattern of the maps. The optimum level of generalization of the land cover map obtained from the aerial photographs for comparison with a land cover map derived from SPOT XS data was found at a resolution of 41m for two generalization levels of the thematic content. The spatial structure of a land cover map, as measured by a set of landscape metrics, is thus a good indicator of the level of generalization of this map. Secondly, the method was applied by integrating a land cover map obtained from aerial photographs of 1954 with a land cover map obtained from a SPOT XS image of 1992.     

Quantifying the effects of hydrological changes on long-term water quality trends in temperate reservoirs: insights from a multi-scale,paleolimnological study

Declining water quality in reservoirs is of growing concern in many regions, yet there is still little understanding of long-term water quality trends in these systems. Across the landscape, reservoirs have diverse origins, functions, and operational strategies. In temperate environments, winter water-level drawdown is a common operational practice in reservoirs but the long-term impacts of this hydrological modification has not been extensively studied. We paired a comparative, pre-dam-to-contemporary study (i.e. a top–bottom design) of 12 reservoirs with a detailed paleolimnological study of a focal lake to generate quantitative insights into the relative effect of hydrological changes vs. landscape and climatic drivers on water quality. The focal reservoir, Grand Lac Saint-François, is of relatively similar morphometry, geography, and limnology to our other sites, and has experienced annual winter water-level drawdown of?~?5 m since it was dammed approximately 100 years ago. Based on our top–bottom analysis, we did not find strong correlations between long-term changes in water quality (i.e. diatom-inferred TP estimates) and winter water-level drawdown amplitudes. Instead, reservoir morphometry and watershed characteristics (i.e. geography, maximum depth, and cropland areas) appeared to be stronger drivers of trends across the region. From the detailed paleolimnological analysis, we found that sedimentary pigments and DI-TP concentrations significantly increased over the last century based on Mann–Kendall trend analyses. Breakpoint analyses showed that changes in biological-proxy trends, as well as the sedimentology (i.e. lithology and accumulations rates), coincided with dam construction and the onset of water level regulation. However, given the high variability in metrics and the extent of water level monitoring records, we were unable to quantitatively associate the impacts of drawdown with water quality trends at Grand Lac Saint-François. Conversely, we did find that watershed nutrient surpluses from livestock farming, and warming temperatures were significant explanatory variables of water quality metrics.     

重庆市浅丘带坝区土地利用与景观空间格局分析

选取重庆市沙坪坝区陈家镇为研究区,采用其建立的土地利用现状数据库,运用GIS的图形处理与空间分析功能,生成6种景观格局图并输入Fragstats for ArcView3.X软件,提取景观格局指数,借助于景观格局指数在生态过程与土地利用间所建立的一种关联,分析并探讨土地利用诱发下景观空间格局特征的响应.其结果:水田景观在景观类型中占据着绝对优势,其连接度表现较高,是景观类型明显的基质,受人类活动干扰强;冬水田景观要素接近于水田景观本底,且冬水田景观要素斑块个数、类型面积随着河流缓冲区距离的增大而增加;旱地景观中各景观要素斑块总体上分布比较零散,规律性不强;农村居民点景观要素是建设用地景观的主要类型,其斑块几何形状简单、规整,各斑块间的相似性强,外围边界接近于正方形或者矩形.