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1.
2.
Green spaces (GS) have many functions that can moderate the climate change impact and help prevent disease and thus alleviate public health expenses in a context of aging societies. However, several socioeconomic, demographic and geographic processes may render the access to GS challenging. Moreover, it is often critical to know what type of GS service to develop at a specific place. Also, measurements accuracy issues could be critical for planning and decision making. As an example of what could happen in many other cities of different sizes, we modeled and compared the access to GS, including several of their specific functions, in the Census Metropolitan Areas (CMA) of Montreal and Quebec City in Canada. We used the Quebec Integrated Chronic Disease Surveillance System (QICDSS) (average of 3 million people per year over 1996–2011) to measure over time, the proximity of each individual to the closest GS boundary using travel costs and spatial interaction models. ANOVA models and their corresponding base regressions were used to evaluate the statistical significance of the relationship of GS distances and surface to density, deprivation, gender and age, including interaction terms. The spatial clustering of the reduction of distances to GS was evaluated on a chronological basis. Unlike the larger CMA of Montreal, Québec City CMA showed greater equity in access to GS, largely due to the specific geographic insertion of linear GS. The CMA of Montreal showed an improvement in the access to GS which benefits the wealthy in the densest areas on the island of Montreal. Everything happens as if a green gentrification process affects the access to GS in Montreal. Our results suggest that for the promotion of GS as an important element of primary prevention in public health, both the quality or functions of GS and the geographic determinants of their access are of higher importance than a simple consideration of total GS surface per capita as often used by decision makers or public health promoters. They also underline the limits of standard measurements of attraction and accessibility and the complexity for large cities to promote environmental justice, given the complexity of their socio-demographic processes.  相似文献   

3.
Public interventions in support of public health and housing in developing countries could benefit from better understanding of spatial heterogeneity and anisotropy. Estimation of directional variation within geographically weighted regression (GWR) faces problems of local parameter instability, border effects and, if extended to non- spatial attributes, potential endogeneity. This study formulates a GWR model where anisotropy is filtered out based on information from directional variograms. Along with classical regressions, the approach is applied to investigate child anaemia and its associations with household characteristics, sanitation and basic infrastructure in 173 regions of sub-Saharan Africa. Based on ordinary least squares (OLS) results, anaemia prevalence rates are up to three times more responsive to child morbidity (related to malaria and other diseases) than to other covariates. GWR estimates provide similar indications, but also point to poor sanitation facilities as a cofactor of severe anaemia particularly in east and southern Africa. The anisotropy-adjusted GWR is spatially stationary in residuals, and its estimated local parameters are less collinear than GWR with no adjustment. However, similar explanatory power and lack of significant bias in parameters estimated by the latter suggest that directional variation is largely captured by modelled co-movements among the variables.  相似文献   

4.
Comparison is now taken as vital to the constitution of knowledge about cities and urbanism. However, debate on comparative urbanism has been far more attentive to the merits of comparisons between cities than it has been to the potential and challenges of comparisons within cities—to what we call “Intra-Urban Comparison” (IUC). We argue that a focus on the diverse forms of urbanism located within cities may generate critical knowledge for both intra- and inter-urban comparative projects. IUCs highlight the diversity inherent in the category “city,” revealing dimensions of the urban that are central to how cities work and are experienced. We mobilise fieldwork within three cities: Mumbai, Delhi and Cape Town, and consider both how these cities have been historically understood as different urban worlds within a city, and discuss key findings from IUCs we have conducted on infrastructures. We find that IUCs can enhance comparative work both within and between cities: reconceptualising urban politics; attending to the varied and contradictory trajectories of urban life; and bringing visibility to the diverse routes through which progressive change can occur.  相似文献   

5.
Spatial disparities in the price of residential heating fuel may have considerable impacts on social well-being. Dependence on relatively expensive fuels in off-gas grid contexts may be linked to high rates of fuel poverty, making it a key policy issue. However, fuel prices in the off-grid sector have received relatively little research attention. This study investigates pricing structures within the heating oil market in Northern Ireland, a region with high rates of fuel poverty, using applied spatial analysis. The results indicate significant spatial variations in the price of heating oil at local level. High prices occur in remote rural areas and urban areas with high rates of gas heating. Prices appear to arise from a complex set of interacting factors related to local market structures, supply costs, market competitiveness and socio-economic factors which affect demand. This study makes a significant contribution to the literature on off-gas residential heating. Although further research is needed, the results presented here suggest that policy responses such as price regulation may have only limited impacts on fuel poverty levels, emphasizing the importance of maximising access to more affordable fuels (e.g. mains gas or renewables) as part of a sustainable energy solution.  相似文献   

6.
Disparities in park provision raise environmental and health justice concerns. With public agencies stepping back from providing environmental amenities in increasingly neoliberal urban regimes, nonprofits in the U.S. have assumed a prominent role in the parks and recreation sector. But very few studies have comprehensively assessed whether and how park nonprofits contribute to increasing or closing the equity gap in park provision. Focusing on Los Angeles, I analyze how park nonprofits operate and which demographic groups benefit from new and improved parks supported by nonprofits. Based on interviews with local practitioners and geospatial analyses, I find that nonprofits are leading a park equity movement in Los Angeles and helped address park disparities. To do so, nonprofits built diverse coalitions, leveraged complementary strengths, coalesced with public agencies, and helped generate public funds for parks. These findings show that equity-oriented nonprofits can successfully challenge the unjust outcomes of neoliberal governance.  相似文献   

7.
The deserts of North America and elsewhere may serve as ‘ecological petri dishes’ that can be used to study the general effects of global climate change (GCC) as these regions are expected to become warmer and drier at faster rates than other terrestrial regions. We highlight the biological and societal responses to such shifts in environmental parameters predicted to vary with GCC, and we introduce the term tolerance mechanism (TM) to inclusively describe the means by which organisms of natural systems or human society cope with such environmental challenges. We review the historical relationships between biological TMs and water availability, temperature, and energy resources, as well as describe societal TMs. We create a simplified conceptual model to predict the effectiveness of TMs in the context of GCC and conclude that, although currently functional, some desert TMs (e.g., biological adaptations by long-lived taxa) may be outpaced by GCC. We finish with suggested future TM-related research.  相似文献   

8.
The Arctic climate is changing, carrying wide-ranging implications for indigenous and non-indigenous inhabitants, businesses, industry and government across the circumpolar region. The latest scientific assessments indicate that change is happening faster than previously thought, and that the Arctic will continue to experience dramatic climate change in the future. This special edition of Polar Research brings together nine papers on climate change impacts, adaptation and vulnerability in the Arctic, providing important insights on the nature of the risks and opportunities posed by climate change in the circumpolar region, highlighting opportunities for policy response and providing insights on how to conduct effective climate change research with Arctic communities.  相似文献   

9.
We used an isotopic mass-balance model to examine how the hydrogeologic setting of lakes influences isotopic response of evaporating lake water to idealized hydroclimatic changes. The model uses a monthly water and isotope balance approach with simplified water-column structure and groundwater exchanges. The framework for comparative simulations is provided by lakes in a region of the Northern Rocky Mountains that display high interlake geochemical variability, thought to be controlled by groundwater hydraulics. Our analysis highlights several isotopic effects of flow between aquifers and lakes, leading to possible divergence of isotopic paleorecords formed under a common climate. Amplitude of isotopic variation resulting from simulated climate forcing was greatly damped when high groundwater fluxes and/or low lake volume resulted in low lake fluid residence time. Differing precipitation and evaporation scenarios that are equivalent in annual fluid balance (P−E) resulted in different isotopic signatures, interpreted as a result of evaporation kinetics. Concentrating low-δ groundwater inflow during spring months raised springtime lake δ values, a counterintuitive result of coincidence between times of high groundwater inflow and the evaporation season. Transient effects of reduced fluid balance caused excursions opposite in sign from eventual steady-state isotopic shifts resulting from enhanced groundwater inflow dominance. Lags in response between climate forcing and isotopic signals were shortened by high groundwater fluxes and resulting short lake residence times. Groundwater-lake exchange exerts control over patterns of lake isotopic response to evaporation through effects on lake residence time, inflow composition, and seasonal timing of inflow and outflow. Sediments from groundwater-linked lakes, often used for paleoenvironmental analysis, should be expected to reflect isotopic complexities of the type shown here. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

10.
Future climate change potentially can have a strong impact on the African continent. Of special concern are the effects on food security and the restricted adaptive capacity of Africa's poverty stricken population. Targeted policy interventions are, therefore, of vital importance. While there is a broad consensus on selection of climate and agricultural indicators, a coherent spatial representation of the populations' vulnerability is still subject to debate, basically because important drivers at household and institutional level are captured at the coarser (sub)-national level only. This paper aims to address this shortcoming by capitalizing on available spatially explicit information on households, food security institutions and natural resources to identify and characterize vulnerable groups in climate change prone areas of East and West Africa. First, we identify and localize groups with varying degrees of vulnerability, using food security and health indicators from georeferenced household surveys. Second, we characterize these vulnerable groups using statistical techniques that report on the frequency of occurrence of household characteristics, social bonding, remittances and agro-ecological endowments. Third we localize areas where climate change conditions affect production of major staple crops even after a maximum adaptation of crop rotations. Fourth, we characterize the vulnerable groups in the climate change affected areas and compare their profiles with the overall assessment to elucidate whether generic or climate change targeted policies are required. Since climate change will impact predominantly on agricultural production, our analysis focuses on the rural areas. For West Africa, we find that vulnerable groups in areas likely to be affected by climate change do not fundamentally differ from vulnerable groups in the study area in general. However, in East Africa there are remarkable differences between these groups which leads to the conclusion that in this part of Africa, poverty reducing strategies for climate change affected areas should differ from generic ones.  相似文献   

11.
陈果 《地理学报》2015,70(12):1973-1986
社会公正是当前地理学的一个热点也是传统研究课题。住房问题往往是社会公正研究和实践的重点案例。中国住房制度改革之后,中国住房拥有率及人均住房面积均大幅度提高。然而在住房分配的过程中,不平等和不公正现象时有发生。如何区别平均和公正,如何看待中国住房改革中的社会公平与不公共存的现象,是了解中国新城市现象的一个重要途径。本文从近期西方政治学和地理学关于住房权(housing rights)、社会公正以及城市权利等文献的讨论出发,通过在广州的实证研究,运用结构方程模型和Pratt指数对涉及住房权主要方面的住房分异的发生途径及其公正性进行综合分析。实证研究说明在住房分配领域,存在着制度因素延续下来所导致的分异。一些制度因素已经转化为市场因素,直接或间接影响个人居住条件和住房所有权的获得,并通过后者进一步影响住房分异。与此同时,纯粹市场因素的影响则相对薄弱。上述结论有助于了解当前中国城市住房权的核心问题,认识社会公正的发展前景,以及探寻减少社会不公正的制度利器。  相似文献   

12.
Geographers have traditionally been interested in the issue of territorial justice conceived in terms of distributional equality. The German constitution incorporates a concept of financial equalization with the objective of creating equivalent living conditions throughout the federal territory. This primarily involves the redistribution of finance, the regulation of which has been a continual source of conflict. The paper looks at the role of the Federal Constitutional Court in mediating such conflict. The Court is the ‘supreme guardian of the constitution’ and a highly influential policy-making institution within the German political system. Commentators have described a process of the judicialization of politics, with an increasing number of important political decisions being taken by the Court, rather than in Parliament. The decisions of the Court within the sphere of financial equalization are examined in this light. Further, the particular relevance of a geographical perspective in this regard is highlighted.  相似文献   

13.
Rainfall is the major driver of crop growth in Mediterranean agricultural regions and its spatial and temporal distributions determine yield potential. This study uses a long term spatial archive of rainfall observations for the Eyre Peninsula (South Australia) to estimate the spatial and temporal impacts of climate change on wheat yield. The three step process involved: (1) cluster analysis and statistical comparison to spatially distinguish heterogeneous “hazardscapes” (places that represent the physical susceptibility to hazards (Khan, 2012)); (2) using historical rainfall reliabilities to estimate the probability of receiving rainfall within a range of predefined thresholds and season for each hazardscape; (3) applying 2030 and 2070 climate change projections to determine the potential future impacts on rainfall. Nine hazardscapes were spatially differentiated each having temporally different historical seasonal rainfall reliabilities. Variations over space and time mean that the impacts of climate change will be spatially explicit. Projected rainfall reductions for 2030 showed marginal impact on hazardscapes with low seasonal reliabilities, primarily in winter and spring. The 2070 projections showed that some hazardscapes were unlikely to receive past rates of rainfall thus limiting the ongoing prospects of current and perhaps the potential adoption of alternative rain-fed land uses. Reductions in rainfall for hazardscapes with higher historical rainfall reliabilities will cause negative impacts on crop development. The ability to quantify the potential spatial and temporal impacts of climate change on seasonal trends will inform land managers' climate change mitigation and adaptation pathways.  相似文献   

14.
Chironomids have been used extensively for reconstructing past temperatures from the late glacial chronozone but far less work has focused on their use as temperature proxies throughout the Holocene, and little work has been undertaken within the UK. Northern England does have many detailed palaeoclimate records, although the majority of these are reconstructions from ombrotrophic peat bogs, which yield a combined temperature and precipitation proxy record. A lake sediment core from Talkin Tarn, dating back 6000 years, was therefore analysed for chironomid remains in an attempt to produce a Holocene temperature reconstruction. Although chironomids have been shown to respond to air temperature by many modern training sets, it is also known that they can respond to other environmental factors. Pollen and loss-on-ignition analyses were therefore undertaken to ascertain whether the lake had been subjected to major environmental changes. Some anthropogenic changes in land use were detected, which may have affected the lake water chemistry and sediments, but they seem to have had little direct impact on the chironomid fauna for the majority of the record. Part of the geology of the catchment is limestone, which suggests that the lake may be buffered against any changes in pH. A chironomid-inferred mean July temperature transfer function from a Norwegian training set was applied to the chironomid data and produced a reconstruction with significant fluctuations throughout the later Holocene, which were associated with cold and warm stenotherms within the assemblages. The uppermost chironomid sample from the lake core (less than 100 years old) has a reconstructed temperature of 14.6 °C (± sample-specific error of 1.18 °C), which compares well with the contemporary mean July average of 14.8 °C. It is therefore concluded that chironomids can be used to reconstruct Holocene temperature, provided the site is well-buffered in relation to pH changes and can be shown not to have been influenced to any great extent by anthropogenic disturbance.  相似文献   

15.
Geografisk Tidsskrift, Danish Journal of Geography 106(2):7–20, 2006

In its Regional Plan of 2005, The Greater Copenhagen Authority (abbreviated as “HUR” in Danish) places special emphasis on the future recreational values associated with the regional green structure. In this paper, the development of the urban green structure in Greater Copenhagen is elaborated upon, focusing on land use changes and the effectiveness of regionally coordinated planning measures. EU MOLAND data are used to analyse the development of the region's green structure during the period 1954 to 1998. Analysis of two “green wedges” within the green structure illustrates that the development of the green recreational areas is the result of both formal and more informal planning initiatives. Development has shown equal phases that correspond to the applied regional planning measures and the general economic conditions. However, local preferences in the involved municipalities likewise have played an important role and have resulted in different urbanisation pressure within the two wedges. Land use has transformed from an agricultural to a primarily recreational landscape. In some areas, however, urbanisation pressure has resulted in residential and green industrial areas instead of the planned recreational land use. Based on its historical development it is concluded that future preservation and development of the green structure in Greater Copenhagen requires regional planning measures to be incorporated into municipal plans. In this way the increasingly independent municipalities will comply to objectives of the Regional Plan 2005.  相似文献   

16.
This study of fossils (pollen, plant macrofossils, stomata and fish) and sediments (lithostratigraphy and geochemistry) from the Wendel site in North Dakota, USA, emphasizes the importance of considering ground-water hydrology when deciphering paleoclimate signals from lakes in postglacial landscapes. The Wendel site was a paleolake from about 11,500 14C yr BP to 11,100 14C yr BP. Afterwards, the lake-level lowered until it became a prairie marsh by 9,300 14C yr BP and finally, at 8,500 14C yr BP, an ephemeral wetland as it is today. Meanwhile, the vegetation changed from a white spruce parkland (11,500 to 10,500 14C yr BP) to deciduous parkland, followed by grassland at 9,300 14C yr BP. The pattern and timing of these aquatic and terrestrial changes are similar to coeval kettle lake records from adjacent uplands, providing a regional aridity signal. However, two local sources of ground water were identified from the fossil and geochemical data, which mediated atmospheric inputs to the Wendel basin. First, the paleolake received water from the melting of stagnant ice buried under local till for about 900 years after glacier recession. Later, Holocene droughts probably caused the lower-elevation Wendel site to capture the ground water of up-gradient lakes.  相似文献   

17.
We compared geographic trends in body mass in a number of populations of the olivaceous field mouse (Abrothrix olivaceus,) along a latitudinal gradient in Chile, and tested the expected neutral tendency resulting from the opposite influences of environmental temperature and aridity across the gradient. Also, we studied water economy through physiological measurements of total evaporative water loss and urine osmolality in individuals from populations inhabiting two contrasting habitats (northern semiarid shrubland and southern temperate rainforest) and acclimated during six months to the same conditions. No change in male body mass with latitude was found across 39 populations. Evaporative water loss in rodents from the semiarid shrubland was significantly lower than that of individuals from the temperate rainforest, and urine osmolality was significantly higher in rodents from the semiarid habitat. We found a better tolerance of water shortage in the rodent population from the xeric habitat, thus suggesting the occurrence of local adaptation to the prevailing habitat conditions. The mechanisms by which rodents regulate their water economy in face of spatial and temporal fluctuations in environmental conditions constitute an essential component of the physiological flexibility that is necessary to cope with challenging climate change scenarios.  相似文献   

18.
To date, little is known about the extent to which the creation of municipal green spaces over an entire city addresses social or racial inequalities in the distribution of environmental amenities – or whether such an agenda creates contributes to green gentrification. In this study, we evaluate the effects of creating 18 green spaces in socially vulnerable neighborhoods of Barcelona during the 1990s and early 2000s. We examined the evolution over time of six socio-demographic gentrification indicators in the areas close to green spaces in comparison with the entire districts. Our results indicate that new parks in the old town and formerly industrialized neighborhoods seem to have experienced green gentrification. In contrast, most economically depressed areas and working-class neighborhoods with less desirable housing stock and more isolated from the city center gained vulnerable residents as they became greener, indicating a possible redistribution and greater concentration of vulnerable residents through the city.  相似文献   

19.
Species distribution models of stray cats were developed using two types of occurrence data: (i) a combined dataset of stray cats and cat colonies in Auckland and projected to the wider New Zealand area; and (ii) population density as an analogue for country-wide stray cat occurrence. These occurrence data, together with sets of environmental variables were used as input to the Maxent modelling tool to produce maps of suitability for the species. Environmental variables used in the models consist of current bioclimatic conditions, and a future climate scenario (RCP8.5 for year 2070 CCSM model). Commonly occurring bias in the modelling process due to latitude, the area for selecting background points in model evaluation, inherent spatial autocorrelation of occurrence points, and correlated bioclimatic variables were explicitly addressed. Results show that the North Island consistently provide more suitable areas for stray cats with increased suitability in a high emission climate change condition. Key protected areas at risk from the increased suitability to stray cats are also presented.  相似文献   

20.
The nature of rainfall events is explored through six years of below average rainfall, associated with negative Southern Oscillation Index (SOI), and three years of above average rainfall, associated with positive SOI (and strong La Niña conditions), at arid Fowlers Gap, Australia. There is a greater probability of rainfall in wet years, but the events themselves also change significantly. Rainfall depth per event was 116% larger on average in wet years than dry, and average event rainfall rate was 85% higher. However, these results are influenced by a small number of very large events in the wet years, and events of <2 mm occur at about the same rate in dry and wet years. Rainfall event profiles in dry years showed more Huff first quartile events likely to promote partitioning of rain into infiltration. In contrast, larger events in wet years showed a preponderance of Huff third quartile profiles likely to be associated with greater partitioning of rainfall into overland flow. This co-variation in rainfall event profile with annual rainfall, not previously described, is reasoned to increase the amplitude of ecological impacts of the SOI-related rainfall variability at this site.  相似文献   

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