基于GIS的丘陵区耕地景观格局时空演变特征分析

以四川省绵阳市涪城区为例,运用景观格局原理与GIS空间分析方法,分析1996--2009年期间耕地景观时空格局及其演变机理（驱动力）。结果表明：13年间,研究区耕地面积呈急剧减少的趋势,变化率明显高于省内丘陵区平均水平;耕地景观空间格局稳定性逐步降低,格局时空变化的地形分异特征显著;变化趋势受坡度、新增建设用地、人口密度、高程、城镇化水平、GDP、起伏度等负向驱动力与灌溉条件、等级公路水平、土地整理程度等正向驱动力因子共同影响。     

基于3S技术的城市辐射效应景观分析——以蓬莱市为例

本文在3S技术的支持下采用缓冲区分析,从景观和斑块两个层次对蓬莱市城市辐射效应与景观结构关系进行了研究。结果表明:在景观层次上,随着城市辐射距离的增加,景观破碎化降低。在斑块层次上,蓬莱市的城市辐射效应对果园和水浇地的影响较大,最大距离是25km;对其他斑块类型影响不大。这表明山东半岛城市化进程加剧了景观的破碎化,而且这一过程主要是通过影响果园和水浇地斑块来实现的。     

基于GIS的中国南方传统聚落景观保护管理信息系统初步研究

中国南方广大地域范围内分布着为数众多的传统聚落,它们历经沧桑而幸存至今,成为聚落文化景观的“活化石”,包含着丰富的历史文化信息,是一笔宝贵的历史遗产。但在城市化的进程中,它们面临着被损毁的厄运,因此加强对这些传统聚落的保护研究就显得十分必要。引进G IS技术来进行传统聚落景观管理是一个值得探索的方向;以南方地区208个经典古镇作为研究样本,初步建立我国南方传统聚落景观保护管理信息系统,就是这种探索的有益尝试。通过对该系统的目标与意义、结构与功能、技术路线的选择、后续功能的构想等方面的阐述,证实了应用G IS技术可以实现传统聚落景观的多源数据集成与管理;指出了民居建筑数据库作为文化遗产数字化的一个方向,对文化传承和历史记忆的延续具有不可替代的作用。     

Measuring the relationships between landscape aesthetics suitability and spatial patterns of urbanized lands: an informed modelling framework for developing urban growth scenarios

This study develops an informed modelling approach that follows a bottom-up planning strategy to define plausible urban growth scenarios. In this case, landscape aesthetics suitability of the area was first generated using multi-criteria evaluation method. Then, a buffer zone of 1 km was considered to extract the average values of aesthetics suitability scores surrounding urban patches with medium physical size (10–30 hectares). The averaged values were considered as the dependent variable. In the next step, landscape metrics of these urban patches, as explanatory variables, were also computed to measure compositional and configuration-based attributes of urban clusters. Bivariate associations (Pearson correlation analysis) and statistical relationships (linear regression algorithm) between landscape metrics and their associated aesthetics values were measured and modelled. According to the results, both composition and configuration values are significantly correlated to the dependent variable in which configuration-based attributes depicted a stronger explanatory power.     

The urban greenness score: A satellite-based metric for multi-decadal characterization of urban land dynamics

Canada’s urban areas have experienced extensive growth over the past quarter century; however, there has been no consistent, spatially explicit approach for quantifying the loss and gain of greenness in cities nationally. Herein, we developed a novel urban greenness score metric using greenness fractions from a multi-decadal time series (1984–2016) of spectrally unmixed annual Landsat satellite image composites to characterize final year (2016) greenness and its overall change for 18 major Canadian urban areas, summarized by census dissemination area (DA). The applied validation procedure confirmed correlation coefficients (ρ) ranging from 0.67 – 0.85 between reference and estimated greenness fractions, indicating that spectral unmixing is an appropriate method for extracting urban greenness from a time series of medium spatial resolution satellite imagery. Most DAs across Canada sustained a moderate (∼20 % – 40 %) or low (≲ 20 %) level of greenness between 1984 and 2016, but overall there was a decreasing trend in greenness. Eastern urban areas maintained the most greenness over time, while urban areas in the Prairies had the greatest increase in greenness. Densely populated urban areas experienced the greatest loss in greenness (16 % of DAs); whereas, urban areas with a moderately-low density experienced the greatest increase (14 % of DAs). In agreement with previous studies, we found that greenness was negatively associated with urban infilling, with lower greenness levels typically found in urban cores, and greenness loss most often found in the urban periphery in conjunction with urban expansion. Methods presented in this analysis take advantage of the open and longstanding Landsat archive, as well as multiple spatial scales, including sub-pixel unmixing techniques, pixel level greenness faction data summarized for management units, and analysis conducted nationally. The developed urban greenness score provides a comprehensive framework to understand current urban greenness and relate it to its recent past, which supports long-term strategic planning, and can be transferred to other regions across spatial and temporal scales.     

The habitation Model Trend Calculation (MTC): A new effective tool for predictive modeling in archaeology

ABSTRACT

The aim of this paper is to create and present a new archaeological predictive model via GIS, incorporating what archaeologists consider the most important criterion absent of similar past models, that of critical thinking. The new model suggested in this paper is named habitation Model Trend Calculation (MTC) and is not only integrates the archaeological questions with a critical view, but it can be easily adjusted, according to the conditions or the questions concerning the archaeological community. Furthermore, it uses new topographical and geomorphological indexes such as Topographical Index (TPI), Hillslope and Landform Classification that give a new sense of the topographical and geomorphological characteristics of the examined area; therefore this model is a more powerful tool compared to older models that did not use new topographical and geomorphological indexes. The success of the created model is checked as a case study in the region of Messenia, Greece during the Mycenaean era. The region of Messenia is considered as one of the most important Mycenaean regions of Greece due to the great number and the importance of Mycenaean sites identified. For the present paper, 140 habitation sites were divided into four hierarchical categories (centers, large villages, villages, and farms) based on the extent and the plurality of the tholos tombs that exist in the broader region and according to the hierarchical categorization used by the archaeologists who have studied the area. The new predictive model presented in this work can assist in solving a series of criticisms that have been expressed in the previous studies regarding such models. Additionally, in the case of Mycenaean Messenia, the model shows excellent results in relation to the habitats of the time.     

Remote sensing data in lithium (Li) exploration: A new approach for the detection of Li-bearing pegmatites

Remote sensing has proved to be a powerful resource in geology capable of delineating target exploration areas for several deposit types. Only recently, these methodologies have been used for the detection of lithium (Li)-bearing pegmatites. This happened because of the growing importance and demand of Li for the construction of Li-ion batteries for electric cars. The objective of this study was to develop innovative and effective remote sensing methodologies capable of identifying Li-pegmatites through alteration mapping and through the direct identification of Li-bearing minerals. For that, cloud free Landsat-5, Landsat-8, Sentinel-2 and ASTER images with low vegetation coverage were used. The image processing methods included: RGB (red, green, blue) combinations, band ratios and selective principal component analysis (PCA). The study area of this work is the Fregeneda (Salamanca, Spain)-Almendra (Vila Nova de Foz Côa, Portugal) region, where different known types of Li-pegmatites have been mapped. This study proposes new RGB combinations, band ratios and subsets for selective PCA capable of differentiating the spectral signatures of the Li-bearing pegmatites from the spectral signatures of the host rocks. The potential and limitations of the methodologies proposed are discussed, but overall there is a great potential for the identification of Li-bearing pegmatites using remote sensing. The results obtained could be improved using sensors with a better spatial and spectral resolution.     

基于DEM坡度坡向算法精度的分析研究

坡度坡向是两个最基本的地形因子,目前对DEM坡度坡向计算模型和精度存在一些不同的甚至矛盾的观点,其原因在于没有区分误差来源和分析评价方法的不同.本文对DEM坡度坡向误差进行了理论分析,并通过实验数据对相关结论进行了验证.旨在澄清目前关于坡度坡向计算模型上的矛盾结论.     

A framework design for the Chinese National Disaster Reduction System of Systems (CNDRSS)

China is one of the most disaster-prone countries in the world. Currently, the disaster prevention and relief mechanism in China is mainly based on single disaster types and is implemented by different ministries and divisions in single administrative regions. Subsequently, the available resources, including data, services, materials, and human resources, cannot be shared and used effectively. Based on the idea of an observation system of systems and a business system of systems, this paper presents an integrated framework for a Chinese National Disaster Reduction System of Systems (CNDRSS) to address this issue. The CNDRSS framework aims to achieve data sharing and collaboration among different disaster-related ministries/institutions by providing one-stop services for all phases of disaster management and linking together existing and planned disaster-related business systems and observation systems. The key technologies use federated databases and a web service to integrate multiple disaster management systems among different ministries/institutions and a sensor web to integrate airborne, space-borne, and in-situ observations through the web service. These event-driven focused-services connecting the various observations, processing, and mapping processes can meet the requirements for complex disaster-chain systems.     

灰色系统GM(1,1)模型在地铁安全保护监测中的应用

主要阐述了灰色系统GM(1,1)预测模型在地铁安全保护监测中的应用。采用Matlab数值分析,将长江路九号街区地铁安全保护监测工程中的实测数据同GM(1,1)预测模型得到的数据进行精度对比分析,验证了该模型在地铁保护监测中具有一定的可行性及可靠性,表明GM(1,1)模型能良好地运用到地铁保护监测中,为施工安全起到一定的指导作用。     

The comparison index: A tool for assessing the accuracy of image segmentation

Segmentation algorithms applied to remote sensing data provide valuable information about the size, distribution and context of landscape objects at a range of scales. However, there is a need for well-defined and robust validation tools to assessing the reliability of segmentation results. Such tools are required to assess whether image segments are based on ‘real’ objects, such as field boundaries, or on artefacts of the image segmentation algorithm. These tools can be used to improve the reliability of any land-use/land-cover classifications or landscape analyses that is based on the image segments.The validation algorithm developed in this paper aims to: (a) localize and quantify segmentation inaccuracies; and (b) allow the assessment of segmentation results on the whole. The first aim is achieved using object metrics that enable the quantification of topological and geometric object differences. The second aim is achieved by combining these object metrics into a ‘Comparison Index’, which allows a relative comparison of different segmentation results. The approach demonstrates how the Comparison Index CI can be used to guide trial-and-error techniques, enabling the identification of a segmentation scale H that is close to optimal. Once this scale has been identified a more detailed examination of the CI–H- diagrams can be used to identify precisely what H value and associated parameter settings will yield the most accurate image segmentation results.The procedure is applied to segmented Landsat scenes in an agricultural area in Saxony-Anhalt, Germany. The segmentations were generated using the ‘Fractal Net Evolution Approach’, which is implemented in the eCognition software.     

高层建筑物(群)深基坑工程变形监测与信息化施工

城市高层建筑物(群)的地基处理一般采用深基坑开挖技术,随着高层建筑的不断增多,施工难度及要求越来越高,周边建筑物及深基坑施工安全也显得越来越重要。采用适宜的变形监测技术,并对获得的系列资料进行变形分析,进而为信息化施工奠定基础。通过多个深基坑开挖地基处理的工程应用,工程变形监测与信息化施工正显示和发挥着极大的社会效益和经济效益。文章就工程实践为例,对该系统方法及其运用效果进行阐述。     

“GIS工程设计”的实验教学模式研究

"GIS工程设计"的教学目的是培养学生GIS设计的综合能力,因此,该课程的实践教学很重要。本文提出将"GIS工程设计"的实践教学体系分为基础实验和综合设计两部分,研究实践教学安排,改善实习的考核体系和辅助教学方法,形成一套高效的实践教学模式。     

Water-poverty relationships in the coastal town of Mbour (Senegal): Relevance of GIS for decision support

Coastal area is always a zone with complex problems. Due to the attraction they exert, are facing many social problems. Therefore, a coastal city is usually a city with problems. Its extension, caused by the influx of people from different backgrounds, creates an increased demand for services. One of the problems frequently encountered, especially in Senegal, is access to water. The problem of access to water is poorly treated, without being correlated with the urban evolution, i.e. with increasing population and demand growth. The water resource is facing numerous complications such as the lack of integrated management, integration issues at the governance level, where the local factor is often forgotten.The town of Mbour, object of our study, does not come out of that lot, being an attractive coastal city, from an African country. This indicates the need for an integrated management oriented from local to a global basis and not vice versa. The study presented in this paper indicates that a large proportion of the population has not access to a verified drinking water system and uses water from wells or standpipes. Half of the surveyed population (50%) has no access to a water supply system. The water poverty map of the town overlaps with that of the general poverty excepting few neighborhoods. This means that even areas that are not affected by poverty have a very low or poor access to water, which so far remains the perverse effect of the reform of the Senegalese water sector in 1995.     

Classifying airborne radiometry data with Agglomerative Hierarchical Clustering: A tool for geological mapping in context of rainforest (French Guiana)

In highly weathered environments, it is crucial that geological maps provide information concerning both the regolith and the bedrock, for societal needs, such as land-use, mineral or water resources management. Often, geologists are facing the challenge of upgrading existing maps, as relevant information concerning weathering processes and pedogenesis is currently missing. In rugged areas in particular, where access to the field is difficult, ground observations are sparsely available, and need therefore to be complemented using methods based on remotely sensed data.     

A Geographic Information System (GIS)-based approach for relating anthropogenic impact and environmental stress: a case study within the African Albertine Rift

This study introduces a potentially cost-effective methodology to assess habitat quality remotely using anthropogenic variables derived from both Geographic Information System (GIS) and remote sensing. We related anthropogenic impact to organism-level response across the Albertine Rift of East-Africa, which was measured using body condition (BC) in Lophuromys aquilus, the dark-coloured brush-furred rat. We chose seven variables to measure anthropogenic impact, ranging from land cover/land use to nighttime light radiance. Using a principal component analysis, we extracted four components that describe human impact and correlated each with BC. We documented that BC tended to be higher in more disturbed areas. We recommend this GIS-based methodology to relate anthropogenic impact to organismal-level response in the Albertine Rift region, and we provide broad guidelines for its application to assess habitat quality for species of conservation concern.     

新时期专业档案归档问题与对策---以测绘地理信息档案为例北大核心CSCD

本文从规章制度和归档技术两方面综述了专业档案归档的发展现状,并以测绘地理信息档案为例,指出当前专业档案归档工作存在的问题,提出了加强专业档案归档工作的具体措施建议,从源头上加强专业档案归档工作,实现专业档案完整、系统、规范的归档。最后对专业档案归档工作做了展望,提出了加强专业档案归档的技术途径。     

The grey-green divide: multi-temporal analysis of greenness across 10,000 urban centres derived from the Global Human Settlement Layer (GHSL)

ABSTRACT

The presence of green spaces within city centres has been recognized as a valuable component of the city landscape. Vegetation provides a variety of benefits including energy saving, improved air quality, reduced noise pollution, decreased ambient temperature and psychological restoration. Evidence also shows that the amount of vegetation, known as ‘greenness’, in densely populated areas, can also be an indicator of the relative wealth of a neighbourhood. The ‘grey-green divide’, the contrast between built-up areas with a dominant grey colour and green spaces, is taken as a proxy indicator of sustainable management of cities and planning of urban growth. Consistent and continuous assessment of greenness in cities is therefore essential for monitoring progress towards the United Nations Sustainable Development Goal 11. The availability of multi-temporal greenness information from Landsat data archives together with data derived from the city centres database of the Global Human Settlement Layer (GHSL) initiative, offers a unique perspective to quantify and analyse changes in greenness across 10,323 urban centres all around the globe. In this research, we assess differences between greenness within and outside the built-up area for all the urban centres described by the city centres database of the GHSL. We also analyse changes in the amount of green space over time considering changes in the built-up areas in the periods 1990, 2000 and 2014. The results show an overall trend of increased greenness between 1990 and 2014 in most cities. The effect of greening is observed also for most of the 32 world megacities. We conclude that using simple yet effective approaches exploiting open and free global data it is possible to provide quantitative information on the greenness of cities and its changes over time. This information is of direct interest for urban planners and decision-makers to mitigate urban related environmental and social impacts.     

训练样本对TM尺度小麦种植面积测量精度影响研究(Ⅱ)——样本质量对小麦测量精度的影响分析

本文以小麦为例,在构建标准训练样本数据集的基础上,引入欧式距离、马氏距离和纯度三个指标对训练样本数据进行质量评价和分等定级。然后将相同样本数量,但不同质量等级的训练样本输入到最小距离、最大似然和支持向量机三种分类器中进行影像分类和冬小麦提取,并对小麦识别结果进行分析和比较。研究结果显示:同一分类器和不同分类器对相同指标划分的不同质量等级的训练样本响应不同,对不同指标划分的相同质量等级的训练样本响应也不同;相同分类器,面积误差最小和总体像元精度最高所对应的训练样本的质量等级不一样。