Urban sprawl: neighbourhood dissatisfaction and urban preferences. Some evidence from Flanders

Early studies suggest that people living in rural neighbourhoods are more satisfied with their residential location than people living in cities. Consequently, most individuals seem to prefer low-density environments to reside in. More recent studies, however, state that rural residents are no more likely to be satisfied with their residential neighbourhood than their urban counterparts. In addition, a considerable, growing part of the population seems to have a clear preference for urban neighbourhoods. The results of our research, conducted in Flanders, Belgium, suggest that urbanites are more satisfied with their neighbourhood than rural residents are. Neighbourhood preferences differ less between urbanites and rural residents. However, there are differences indicating that urbanites have a preference for rural neighbourhoods and rural residents a preference for urban neighbourhoods. In sum, it seems that people, once they have selected their residential location, are not satisfied with the neighbourhood characteristics and tend to develop a preference for a different neighbourhood type. This mismatch can be partly explained by the strongly developed urban sprawl in Flanders, reducing the residential qualities of urban and especially rural environments. Restricting further urban sprawl, with the help of a more active spatial planning policy, seems necessary to increase neighbourhood satisfaction.     

Grazing effects on patchy dryland vegetation in northern Patagonia

In this study the spatial patterns and dynamics of vegetation patches along a grazing gradient in the steppe ofLarrea divaricataandStipaspp. in NE Patagonia (Argentina) are described. A general effect of grazing is the reduction of total plant cover resulting from the decrease in cover of perennial grasses (Stipa speciosa, Poa ligularis, Stipa tenuis) and some tall shrubs (Chuquiraga hystrix, Bougainvillea spinosa, Lycium chilense). Dwarf shrubs (Nassauvia fueguianaandJunellia seriphioides) increase their cover under medium and/or high grazing pressures. Plant species are spatially grouped into patches which alternate with areas of bare soil. Eleven types of vegetation patch differing in the dominant plant functional type or species, floristic richness and size were identified with different relative frequency along the grazing gradient. Based on these results, it is postulated that grazing forces the replacement of large patches dominated by tall shrubs with high species richness, byLarrea divaricatapatches or small dwarf shrub patches with low species richness and the extinction of grass patches. This results from: (1) disruption of local balances of species deletions and additions; (2) fragmentation of large patches; and (3) formation of new vegetation patches. These changes lead to differing plant spatial organization and heterogeneity along the grazing gradient which may be described by characteristic arrays of vegetation patches.     

Examining the neighbourhood‐level predictors of fear of crime in Christchurch,New Zealand

The fear of crime can significantly reduce the quality of life of individuals, yet little is known about what neighbourhood‐level factors drive feelings of vulnerability in New Zealand. Even less is known about the impact that recorded crime has on individuals' fear in the country. In this study, we examined the neighbourhood‐level factors related to fear of crime in Christchurch, focusing specifically on whether recorded crime in neighbourhoods influences fear. The fear of crime in Christchurch was found to be the greatest in more affluent, ethnically homogenous and residentially stable neighbourhoods, while recorded crime levels were found to be relatively lower in these neighbourhoods.     

汕头市土地利用空间格局的景观生态学分析

根据不同利用类型土地生态效应的异同,对汕头市2003年1∶1万比例尺土地更新调查数据的土地分类系统进行调整,将全部土地景观划分为耕地、林地、园地、草地、居民点及工矿、交通、裸土地和水域等8类.在GIS的支持下,提取各类型土地景观斑块的数目、面积和周长等信息,据此对斑块景观的数量、面积和形状等特征,以及区域景观的多样性、均匀度和优势度,集中性和区际意义等进行分析,从而总结出全市范围及六区一县土地利用空间格局的景观生态学特征.     

“Belonging” in the gentrified Golden Horn/Halic neighbourhoods of Istanbul

Mainstream gentrification research predominantly examines experiences and motivations of the middle-class gentrifier groups, while overlooking experiences of non-gentrifying groups including the impact of in situ local processes on gentrification itself. In this paper, I discuss gentrification, neighbourhood belonging and spatial distribution of class in Istanbul by examining patterns of belonging both of gentrifiers and non-gentrifying groups in historic neighbourhoods of the Golden Horn/Halic. I use multiple correspondence analysis (MCA), a methodology rarely used in gentrification research, to explore social and symbolic borders between these two groups. I show how gentrification leads to spatial clustering by creating exclusionary practices and eroding social cohesion, and illuminate divisions that are inscribed into the physical space of the neighbourhood.     

Desert pavement characteristics on wadi terrace and alluvial fan surfaces: Wadi Al-Bih, U.A.E. and Oman

In arid mountain areas, the dating and correlation of alluvial depositional surfaces is often uncertain. Especially in regions where the geomorphology is not well known, surface modification by the development of soil and desert pavement may allow the correlation of geomorphic surfaces and estimation of at least their relative ages. Pleistocene wadi terraces and associated alluvial fans occur in Wadi Al-Bih, U.A.E. and Oman, for which correlations and age relationships are not known. Three age-related groups of fans and terraces have been identified and mapped on the basis of their morphostratigraphic relationships. Deposition of the oldest terrace sediments and associated fans followed a long period of sustained incision after Miocene uplift of the region. The younger two groups of terraces and fans are inset within the older group. To identify the gross effects of pavement development, comparisons have been made between terrace surface and subsurface particle-size distributions. The older terraces have finer surface sediments and a greater contrast between finer surface and subsurface sediments than the younger terraces. This reflects the degree of pavement development. Particle size on the fan surfaces is comparable with that on the equivalent terrace surfaces. Criteria for the classification of pavements were developed based on clast fracturing and angularity, size, sorting, packing, and surface texture, from which a simple index of pavement development has been derived. Other properties, rock varnish and weathering characteristics, were also recorded; but these proved to be less discriminatory than pavement characteristics. The pavement data have been augmented by observations on soils. Detailed studies of pavements on terraces (8 sites, 12 samples covering the three age groups) and fans (5 sites, 10 samples covering the three age groups) allow differentiation between age-groups. The three terraces show three different age-related pavement types, expressed by differences in the pavement development index. Weakly-developed pavements (little fracturing, sub-rounded clasts, some modification of the depositional fabric, incipient soil development, stage I CaCO₃ accumulation) occur on the youngest terrace and fan surfaces. Moderately-developed pavements (clast fracturing, sub-angular clasts, moderate sorting and packing, deeper soil development, stage II CaCO₃ accumulation) occur on the middle terrace and fan surfaces. Well-developed pavements (complete clast fracturing into small angular fragments, mature sorting and packing of the pavement surface, deep soil development with strong horizonation, stage III CaCO₃ accumulation) occur on the highest terrace and oldest fan surfaces. There are minor differences between the youngest pavements on terraces and fans, which reflect initial sedimentological differences. These differences become less as the pavements develop. On the basis of comparative studies, the oldest terrace is estimated to date from sometime prior to ca. 100 ka BP, the second terrace and the most extensive fan surface from the Late Pleistocene, and the youngest terrace and fan phase from the Latest Pleistocene or Early Holocene.     

Neighbourhoods and health: A review of the New Zealand literature

Over the past two decades, there has been a resurgence of interest into place‐based influences on health. Researchers have identified that various characteristics of neighbourhoods exert an influence on the health outcomes and behaviours of local residents. Understanding the processes linking places to health provides considerable potential for a range of policy interventions. We review the New Zealand‐based neighbourhoods and health research. Consideration is given to the types of neighbourhood characteristics, as well the range of health outcomes that have been studied. Finally, we suggest some priorities for further research into the mechanisms underpinning neighbourhood influences on health in New Zealand.     

晋陕蒙接壤区林草覆盖变化的遥感分析

以晋陕蒙接壤区1986年和2000年的TM影象为信息源,运用遥感技术与地理信息系统技术,结合建立了两期全区土地资源数据库,从中提取林草覆盖空间数据.分析得出2000年全区有林草地面积332.19×104hm2,占总面积的56.87%,其中林地占13.72%,草地占86.28%.14年间林草植被净增加了2.29×104hm2,占林草面积的0.69%,总的变化趋势是林草覆盖对生态环境的保护和调节功能趋向衰减.林地被毁、草地开垦和沙漠化是林草覆盖减少的主要原因,而其新增部分主要是实施植树造林、退耕还林还草等生态环境建设措施的结果.     

中国大城市低收入邻里及其居民的贫困集聚度和贫困决定因素

基于2007 年在中国6 个大城市开展的大规模家庭户调查,采用FGT指数法和逻辑回归分析方法,探讨中国大城市低收入邻里及其居民的贫困集聚程度和决定因素。研究发现,老城衰败邻里的贫困集聚度最高,同时承受多重不利状况的下岗/失业人员的贫困集聚度也是最高;事实贫困、被剥夺感与社会福利分配之间存在不匹配现象。在贫困的决定因素方面,制度保障和市场薪酬对城市贫困的发生具有同等重要的作用,但对不同低收入邻里和不同社会群体又表现出不同的关联性。随着市场作用的加强,市场薪酬机制正在成为贫困产生的更为重要的决定性因素。     

Affective neighbourly relations between migrant and local residents in Shanghai

In urban China there is growing scholarly interest in neighbourhood social interaction, but most studies focus on overt neighbouring activities whilst less is known about the affective dimension of neighbourhood relations, such as mutual trust and care. By surveying 1,420 residents from Shanghai, this study examines the affective relationship between rural migrants and local urban neighbours and explores whether the frequency of neighbouring and contextual characteristics may affect this outcome. Our results show that residents who interact more with out-group neighbours also tend to describe their relationship with them as more caring and amicable. Furthermore, residents in working class neighbourhoods tend to rely on intergroup neighbouring as means of facilitating mutual trust. In contrast, residents of neighbourhoods with commodified housing stock already possess a strong affective relationship with out-group neighbours because of a shared identity as middle-class homeowners and, therefore, do not rely on neighbourly interactions as a facilitator of neighbourly trust.     

伊洛河流域不同地貌类型区的景观空间结构对比分析——以洛宁县为例

运用景观生态学原理,借助遥感和地理信息系统技术,选取斑块密度、边缘密度、分维数、景观多样性、景观优势度和破碎化指数等指标,对比分析了伊洛河流域的洛宁县不同地貌类型区的景观空间分布和空间格局特征,探讨了该地区不同地貌类型区人类活动与景观结构之间的关系。结果显示从南北中山区向内到南北低山区到南北塬陵区再到川涧区,斑块破碎化指数从0.0190到0.3225到0.4378再到0.1794,总体呈增加趋势,破碎化程度增大,川涧区则由于遥感影像解析精度问题,使得破碎化指数低于塬陵区;景观多样性指数从0.1828到0.3586到0.2983再到0.3634,总体也呈增大趋势;平均斑块分维数从1.1148到1.3854到1.2263再到1.3680,呈两低两高分布。     

Vegetation heterogeneity in Monte Desert ecosystems: A multi-scale approach linking patterns and processes

We review the current state of research on vegetation heterogeneity in the Monte Desert at scales varying from landscape to intra-patch. Different factors are related to vegetation heterogeneity at every scale. At a coarse scale (i.e. landscapes and communities) vegetation heterogeneity is commonly determined by abiotic factors, whereas biotic interactions usually influence fine scale (patch, intrapatch) heterogeneity. Communities are distributed at the landscape scale according to differences in precipitation, topography and soil attributes. On the other hand, there is evidence that the spatial pattern of plant patches within communities is determined by runon –runoff processes, although biotic influences such as grazing can induce changes in the spatial pattern of patches when plant cover is strongly reduced. In the same way, at patch and intrapatch scales, biotic interactions (i.e. plant –plant interactions, grazing) determine the size and the species composition of plant patches as well as the distribution of species inside plant patches. However, the mechanisms operating behind such biotic interactions at small scales are commonly related to plant-induced changes in the physical environment. We also found evidence of cross-scale interactions, feedbacks, and non-linear effects such as those induced by grazing disturbance. Our analysis showed some regional differences in patterns and processes related to vegetation heterogeneity along the Monte Desert which can be ascribed to climatic and taxonomic variation among areas. Although information about vegetation heterogeneity and its causes and consequences in the Monte Desert is abundant, some areas where knowledge is scarce are detailed.     

Desert pavement development and landscape stability on the Eastern Libyan Plateau, Egypt

Desert pavement surfaces of the eastern Libyan Plateau in central Egypt represent a stable landscape preserving Middle and Upper Paleolithic artifacts. Detailed measurements of pavement clasts indicate significant variability in clast size, density, lithology and orientation between pavements, but no spatial relationship among any of these pavement variables over the study area. Pavement characteristics are unrelated to local geomorphic features including slope gradient and aspect, suggesting a desert pavement surface that has developed without significant influence from transporting mechanisms such as overland flow and slope failure. Meridional vertical cracks in surface clasts implicate thermal stresses due to diurnal solar variation as a mechanical weathering process, whereas the presence of a clast-free silty layer within all soil profiles indicates that these are accretionary pavement surfaces that have grown upward over time. The desert pavement in this region has likely developed in situ through mechanical breakdown of surface clasts and desert pedogenesis, indicating long-term stability for this region and minimal taphonomic effects on artifacts > 2 cm in diameter deposited on this surface over the last ca. 100 ka.     

Automated building generalization based on urban morphology and Gestalt theory

Building generalization is a difficult operation due to the complexity of the spatial distribution of buildings and for reasons of spatial recognition. In this study, building generalization is decomposed into two steps, i.e. building grouping and generalization execution. The neighbourhood model in urban morphology provides global constraints for guiding the global partitioning of building sets on the whole map by means of roads and rivers, by which enclaves, blocks, superblocks or neighbourhoods are formed; whereas the local constraints from Gestalt principles provide criteria for the further grouping of enclaves, blocks, superblocks and/or neighbourhoods. In the grouping process, graph theory, Delaunay triangulation and the Voronoi diagram are employed as supporting techniques. After grouping, some useful information, such as the sum of the building's area, the mean separation and the standard deviation of the separation of buildings, is attached to each group. By means of the attached information, an appropriate operation is selected to generalize the corresponding groups. Indeed, the methodology described brings together a number of well-developed theories/techniques, including graph theory, Delaunay triangulation, the Voronoi diagram, urban morphology and Gestalt theory, in such a way that multiscale products can be derived.     

Living where others dare not: Microhabitat distribution in Chorizanthe rigida,a serotinous desert annual

We studied the small scale distribution pattern of Chorizanthe rigida, a serotinous desert annual, in a shrub-mound-to-desert-pavement gradient. Two sites were established in the Mojave Desert and two sites where established in the Sonoran Desert. We placed transects along a soil surface gradient from shrub mounds to desert pavements, and measured land surface properties, soil characteristics, and C. rigida's small scale distribution. A Principal Components Analysis was done on the resulting site × soil variables matrix. C. rigida established preferentially in desert pavements outside shrub canopies. Pavements showed finer soil textures and higher electrical conductivities, while shrub mounds had sandy textures, low surface rockiness, higher nitrogen, and higher cover of annuals. We discuss a probable relationship between seed retention and the establishment on desert pavements: timing seed release allows this species to avoid wind- or animal-induced seed dispersal into shrub mounds and establish outside the nurse mounds, where most annual plants concentrate. The seeds encased in the serotinous involucres, released after rains, are dispersed by run-off into the desert pavements and transition zones where, once developed, the dead seed-retaining structures of adult C. rigida plants persist for years releasing seeds to subsequent rain events.     

科尔沁沙地水域景观格局的时空动态——以奈曼旗为例

对位于科尔沁沙地腹地的奈曼旗近30 a来土地利用/覆被信息中水域类型的景观格局指数进行了时空组合分析。结果表明,大尺度研究区（8 135.15 km2）1975-1985年水体与湿地斑块的类型面积和数量增加,形状趋于复杂;1985-2005年斑块类型面积和数量大幅减少,形状趋于简单;中尺度研究区（892.74 km2）水体与湿地斑块的类型面积在波动中减小,湿地斑块数量减少和形状简单化的转折期相对较短且滞后于水体。小尺度研究区（110.42 km2）集中了人畜以及上游活动的干扰,水体与湿地斑块仅在个别时期出现,难以连续存在。在各尺度研究区内,河漫滩斑块类型面积变化趋势各异,数量和形状复杂程度都相对稳定;且随着研究区增大形状更加不规则。水域类型的景观格局虽然在不同时空上的动态过程存在差异性,但其发展方向具有相同趋势,发展过程受到气候波动和人类活动干扰的共同影响。     

Cosmogenic He exposure ages of Pleistocene debris flows and desert pavements in Capitol Reef National Park, Utah

The Quaternary history of the Capitol Reef area, Utah, is closely linked to the basaltic-andesite boulder deposits that cover much of the landscape. Understanding the age and mode of emplacement of these deposits is crucial to deciphering the Quaternary evolution of this part of the Colorado Plateau. Using cosmogenic ³He exposure age dating, we obtained apparent exposure ages for several key deposits in the Capitol Reef area. Coarse boulder diamicts capping the Johnson Mesa and Carcass Creek Terraces are not associated with the Bull Lake glaciation as previously thought, but were deposited 180±15 to 205±17 ka (minimum age) and are the result of debris flow deposition. Desert pavements on the Johnson Mesa surface give exposure ranging from 97±8 to 159±14 ka and are 34–96 kyears younger than the boulder exposure ages. The offset between the boulder and pavement exposure ages appears to be related to a delay in pavement formation until the penultimate glacial/interglacial transition or periodic burial and exposure of pavement clasts since debris flow deposition. Incision rates for the Capitol Reef reach of the Fremont River calculated from the boulder exposure ages range from 0.40 to 0.43 m kyear⁻¹ (maximum rates) and are some of the highest on the Colorado Plateau.     

广州市土地覆被格局异质性的尺度与等级特征

基于SPOT遥感数据源形成广州市土地覆被类型图,在中心城区选取互相垂直的南北和东西两条样带,用Fortran编程计算各样带在125m、250m、500m和1000m 4个幅度下的景观多样性指数,以及Moran I、Geary C系数和半变异函数。再将样带分别自北向南和自西向东等间距划分,形成一系列面积相等的区域,计算各区域以及样带整体上的多样性指数的尺度方差。结果表明,土地覆被景观多样性在不同的研究幅度下都存在正的空间自相关性,并具有方向性。尺度方差结果显示,尺度方差与尺度和幅度都有关,随着研究尺度增大,尺度方差都呈下降之势,而随幅度增大,尺度方差并非单调变化。如125m和250m两种幅度时,方差随着尺度增大而减少。尺度方差结果进一步揭示研究样带上土地覆被存在多尺度等级结构,并且具有方向性特点,同时也反映尺度方差不失为景观异质性研究的一种有效方法。     

Spatial and temporal variations of vegetation in Qinghai Province based on satellite data

This paper used five years (2001-2006) time series of MODIS NDVI images with a 1-km spatial resolution to produce a land cover map of Qinghai Province in China. A classi-fication approach for different land cover types with special emphasis on vegetation, espe-cially on sparse vegetation, was developed which synthesized Decision Tree Classification, Supervised Classification and Unsupervised Classification. The spatial distribution and dy-namic change of vegetation cover in Qinghai from 2001 to 2006 were analyzed based on the land cover classification map and five grade elevation belts derived from Qinghai DEM. The result shows that vegetation cover in Qinghai in recent five years has been some improved and the area of vegetation was increased from 370,047 km2 in 2001 to 374,576 km2 in 2006. Meanwhile, vegetation cover ratio was increased by 0.63%. Vegetation cover ratio in high mountain belt is the largest (67.92%) among the five grade elevation belts in Qinghai Prov-ince. The second largest vegetation cover ratio is in middle mountain belt (61.80%). Next, in the order of the decreasing vegetation cover ratio, the remaining grades are extreme high mountain belt (38.98%), low mountain belt (25.55%) and flat region belt (15.46%). The area of middle density grassland in high mountain belt is the biggest (94,003 km2), and vegetation cover ratio of dense grassland in middle mountain belt is the highest (32.62%), and the in-creased area of dense grassland in high mountain belt is the greatest (1280 km2). In recent five years the conversion from sparse grass to middle density grass in high mountain belt has been the largest vegetation cover variation and the converted area is 15931 km2.