City-wide relationships between green spaces,urban land use and topography

The growing proportion of human populations living in urban areas, and consequent trends of increasing urban expansion and densification fuel a need to understand how urban form and land use affect environmental quality, including the availability of urban green spaces. Here we use Sheffield as a case study of city-wide relationships between urban green space extent, quality (vegetation cover and tree-cover), and gradients in urban form and topography. The total area of buildings and length of the road network are equally strong negative predictors of extent of green space, while the former predictor is a more important negative influence upon green space quality. Elevation positively influences extent of green space but negatively influences tree-cover. In contrast, slope of terrain positively influences green space quality and is the best predictor of tree-cover. Overall housing density is a more important negative predictor of extent of green space and tree-cover than the densities of individual housing types. Nevertheless, the latter are more important influences upon levels of vegetation cover. Threshold effects of densities of different housing types suggest opportunities for optimising green space quality, with implications for housing policy. Variation in ecological quality of green space may partly reflect different historical intensities of industrial activity.     

Birds and the urban environment: the value of green walls

The simplest form of a ‘green wall’ is where self-adhering climbing plants colonise vertical surfaces, an approach that has been used on buildings for millennia (Koehler 2008). Green walls in urban areas are now well-known for their insulation and air cleaning capacities, but little is known of their value as habitats for wildlife. This paper presents preliminary findings of their value for urban birds. The abundance of birds, on 27 green walls and within the area enclosed by a semi-circle of 10 m radius immediately surrounding them, was compared with 27 walls without vegetation (bare walls) and similar surroundings. The study was carried out during the summer and winter of 2010–11 in north Staffordshire (UK). Birds exploited the green walls for various reasons (including nesting, food and shelter) but were never found on bare control walls. The roofs of buildings and the surrounding vegetation were used by birds in both regimes, but birds were more abundant in areas with green walls. The use of green walls by birds depended on the time of day, the season and whether the vegetation was evergreen or deciduous. The birds’ activity was always restricted to the upper half of the wall vegetation. Green walls and the immediate surroundings were used by some species of conservation concern in Great Britain (e.g. Passer domesticus and Sturnus vulgaris). Therefore, encouraging householders and businesses to grow vegetation up walls may be an effective way of providing a range of resources for birds in urban areas without the need for expensive additional land-take.     

Relationships between urban green land cover and human health at different spatial resolutions

Relationships between landscape patterns and ecological processes can vary with changing resolution. Many studies in ecosystem services and human health rely on spatial-dependent data, yet the effects of changes in spatial resolution on the linkages between landscape and human health are underexplored. This study seeks to address the research gap by exploring the relationships of green land cover and pattern metrics at 1 m, 10 m, and 30 m with life expectancy in the City of Baltimore, Maryland, USA. Spearman’s rho correlation and stepwise and hierarchical regression models were applied. Results showed that the effects of resolution change did not emerge for percent green land cover but were evident in other pattern metrics. Multivariate relationships showed that metrics at 1 m explained the most variability of the relationships between green land cover and life expectancy after controlling for potential confounding factors (adjusted R²?=?0.776, and 0.752 at 10 m and 0.747 at 30 m). Edge density of coarse vegetation was significantly associated with life expectancy at 1 m (adjusted odds ratio [AOR]?=?1.012, 95%CI?=?1.004–1.024, p?<?0.01) and 10 m (AOR?=?1.018, 95%CI?=?1.009–1.027, p?<?0.001) but not at 30 m. Euclidean distance of fine vegetation had a strong positive association with greater life expectancy at 1 m (AOR?=?2.067, 95%CI?=?1.185–4.072, p?<?0.05) but not at 10 m and 30 m. These findings underscore the importance of acknowledging the effects of resolution on the interpretation of landscape-human health relationships and the need for caution when results are used in planning and management decisions.

     

The green factor: Unpacking green job growth

Drawing on data from the Labour Force Survey of the United Kingdom (2011–14), this article estimates the number of green jobs in Scotland and identifies change over time, using a methodological framework that can be applied to any region, based on ISCO‐08 and O*NET. The findings highlight the value of charting changes in green jobs based on inclusive rather than “purist” definitions to better capture the broader impact of greening on jobs. The findings also indicate a need for greater analytical attention to issues of green job quality and inclusive green job growth.     

Spatial distribution and the value of green spaces for urban red-tailed hawks

Raptors increasingly live and nest successfully in urban areas. In the urban landscape of Hartford, CT, red-tailed hawks established home ranges in large green spaces such as parks, golf courses, and cemeteries but also nested successfully in the commercial district of downtown and in densely built urban and suburban neighborhoods. Data collected from 11 radio-tagged breeding adult hawks indicated that year-round home ranges averaged 107.7 ha, much smaller than home ranges reported for hawks inhabiting rural areas. Most hawk home ranges had multiple core areas that were usually associated with favored perches or larger patches of ‘usable’ green space, defined as patches ≥0.25 ha in size, and home range size was positively associated with larger usable green space patches in core areas. Most nests were located in the largest core area and were within a larger patch of green space within the largest core area. Rather than just the amount or size of green space patches, the value of urban green spaces for these hawks likely also varies with the number and proximity of suitable perches such as buildings or tall trees, types and density of prey, and amount of human activity in and adjacent to these spaces. Territoriality and intraspecific competition may also influence home range size and dispersion of red-tailed hawks nesting in Hartford. In this urban area, mortality due to ingestion of rodenticides and collisions with vehicles affected hawk reproductive success.

     

绿色建筑,构建未来的蓝图——绿色建筑在天津的发展

目前,全球能源短缺和环境问题已成为制约人类社会发展的主要矛盾。在1927年斯德哥尔摩举行的联合国人类环境研讨会上,全球代表第一次将“可持续发展”观点搬上议程。经过30年的深化,可持续发展已经达成共识,建筑业作为能源消耗大户由传统的高能耗、高污染型的发展模式逐渐转向高效生态型发展模式,绿色建筑正是实现这一转变的必由之路。     

The ‘green green grass of home’? Return migration to rural Ireland

There have been calls recently to challenge some of the orthodoxies of counterurbanisation. This paper contributes to this by highlighting the complexity of rural in-migration processes, through a focus on rural return migration. There has been a significant increase in return migration to the Republic of Ireland (ROI) since 1996. The paper is based on the life narratives of some of the 1980s generation of emigrants who have recently returned to live in Ireland. It focuses on those Irish return migrants who spent a substantial part of their lives in the large urban centres of Britain and the US, and are currently living in rural Ireland. Their narratives of return are explored in terms of discourses of rurality, in particular through notions of a rural idyll and belonging/not belonging. It is argued that return migrants draw on classic counterurbanisation discourses in their narratives of return, but that these are interwoven with notions of family/kinship. Furthermore, the idyllisation of rural life is complicated by aspects of the specificity of the position of the return migrant. It is suggested that rural return migrants are positioned somewhere between locals and incomers, reflecting the complexity of Irish rural repopulation processes, and that the phenomenon of rural return complicates accepted understandings of counterurbanisation.     

The repeal of the land acts: the challenge of land reform policies in South Africa

This paper analyses South Africa’s land reform policies post-1994 against the backdrop of the apartheid government’s manoeuvres through the repeal of the notorious Land Acts in 1991. The paper concludes that the democratic government could have avoided the challenges of ineffective land reform by taking into consideration land dispossession prior to 1913.     

城市土地经营存在的问题与对策

土地是城市发展不可缺少的资源．是城市存在和发展的载体,科学管理与合理利用土地资源是城市可持续发展的保证。中国的城市土地市场改革开始于1980年末．在此之前中国几乎不存在土地市场．土地的分配和开发严格受国家控制。1988年以后．土地使用权商业化．土地市场开始发育。1991年实施《中华人民共和国城镇国有土地使用权出让和转让暂行条例》,     

The specific value of freedom

This article examines the question of how to assess our overall freedom in terms of its so-called specific value, i.e., the part of its value that can be reduced to the value of the various specific things we are free to do or be. It is argued that existing preference-based freedom rankings may fail to capture this value adequately and, drawing on earlier work by Puppe (J Econ Theory 68:174–199, 1996; in: Laslier et al. (eds.) Freedom in economics. New perspectives in normative analysis, 1998) and Puppe and Xu (Soc Choice Welf, this issue, 2010), an alternative, more general framework is proposed. Two rankings of freedom’s specific value are axiomatically characterized. The article concludes with a discussion of possible extensions of the framework.     

The value of planned death

In this paper we propose a theoretical model of evaluating the economic costs and benefits of physician assisted suicide (euthanasia). The contemplation of euthanasia is modeled akin to the valuation of a real option. Our modeling of the decision shows that euthanasia is optimal when certain conditions are satisfied. The findings in this paper suggest that if more money is spent on medical research (such as pain management), the demand for Euthanasia could be reduced.     

The value of being precise

This study investigates how individuals assess imprecise information. We focus on two essential dimensions of decision under uncertainty, outcomes and probabilities, and their respective precision. We believe the precision of information is highly relevant in the investment setting, as reflected in the well-known “home (familiarity) bias”, and the outcome and probability dimensions, separately or jointly, may affect investors’ knowledge of uncertainty and perceived risk of the investment options, and subsequently affect investors’ choices. To test this conjecture, we conducted three experiments. Our results show that 1) participants demonstrate a pattern of preference for precision and aversion of extreme vagueness and associate vagueness with higher perceived risk and lower investment (experiments one and two); 2) participants prefer vague outcome information to vague probability information (experiment two); 3) familiarity indeed positively affects the precision of estimated values, but this association is stronger for the outcome dimension than for probabilities (experiment three). Our results confirm that precision in information, especially in the outcome dimension has an impact on investors’ resource allocation choices.     

陆桥经济带协作发展的战略构想

陆桥经济带的东部口岸是江苏的连云港市和山东的日照市,西部口岸是新疆的阿拉山口,陇海-兰新铁路干线是该地带的经济大动脉.它东连太平洋,西接大西洋,成为横跨亚欧大陆的国际大通道,也是惟一横贯我国东、中、西部的经济长廊.它有东西两个口岸,向东可以走海路,向西可以走陆路,是我国走向中亚、西亚、东欧、西欧的最捷径.该经济带内包括新、甘、青、宁、陕、晋、豫、皖、苏、鲁10个省区,360万平方公里的地域和近3亿人口,各种社会经济资源丰富.因此,加快这一地带的经济协作和区域联合,对于推动我国从沿海到内地再到边疆大范围的经济提升与发展具有极为重要的战略意义;同时,对于亚太经济、环太平洋经济乃至世界经济也会产生重要的影响.     

The value of conducting door-to-door surveys

This paper argues that door-to-door surveys are a valuable tool for collecting information about health and the environment in urban areas in a manner consistent with community-based participatory research principles. We describe in detail how a door-to-door survey on food shopping and physical activity was conducted with the primary food shopper in 514 households on 30 randomly selected blocks in West and Southwest Philadelphia over seven weeks during the summer of 2010. We identify the elements of our door-to-door protocol that had benefits for the quality of the data collected, flow of data collection, the perceived safety of interviewers and residents, and that informed subsequent phases of this multimethod four-year study of urban food and physical activity environments. We conclude that door-to-door surveys are appropriate and valuable in certain research contexts, when spending time in a community, conducting observations and building relationships are central to the goals and success of a study.     

The influence of plant type on green roof rainfall retention

Urban Ecosystems - Green roofs can mitigate the flood risk by reducing the volume of runoff through direct interception and subsequent evapotranspiration (ET), but the planting choices can...