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1.
Beach Profiles surveys and gale climate data were utilised to assess medium timescale beach rotation at four beaches located along the shores of a crenulated embayment within Swansea Bay, Southwest Wales. The proposed Tidal Lagoon is located within this Bay. Results identified a 7 year (1998–2005) record of cyclic summer/winter rotation and a 14 year (1999–2013) record of annual rotation within the subaerial zone on all four assessed beaches. In the absence of headlands to trap sediment it is asserted that the driving force for beach rotation is the presence of Swansea Dockland/Tawe dredged channel complex, Port Talbot Harbour and the Neath dredged channel which form surrogate headlands essentially creating four separate beach systems through restricting sediment by-pass. Seasonal averaged wind and wave variables showed differing correlation with volume changes and cross-correlation results showed that volume variation lagged behind forcing variables by up to six months (i.e. the resolution of the data). This was confirmed by the annually averaged results which showed only subtle correlation. Here volume change in most cases lagged forcing variables by less than one year. Based on correlations, wind direction variability follows closely with volume changes but wind speed, wave period and height are generally opposite. Initial results suggest that the proposed Swansea Bay Tidal Lagoon, located between sediment cells and surrogate headlands, would have little negative effect on subaerial coastal processes. These datasets will be used as a benchmark for monitoring prior to, during and post construction, with results being used to update and inform subsequent strategies.  相似文献   

2.
Environmental inequalities are a common characteristic of urban areas. Environmental inequality is the unequal spatial distribution of environmental risks and goods among social groups. As environmental inequalities are inherently a spatial matter the choice of scale is essential for correctly understanding inequality issues and for designing proper and effective mitigation policies. However, the potential effects of scale of analysis on inequalities results have largely been underestimated in the assessment of environmental inequalities, leading to contradictory results from different studies. In this study we assess the patterns of environmental inequalities and associated scale issues in the city of Santiago (Chile) using a hierarchical multiscale approach. Our approach focuses on the analysis of spatial relationships between three environmental (i.e., surface temperature, air pollution, vegetation cover) and two socio-demographic variables (i.e., household wealth, population density) on multiple grain sizes and extents. We used census data, remote sensing data, and air pollution monitoring stations to generate raster layers at five grain sizes and five nested extents. We tested for inequalities through Pearson correlation analysis resulting in a total of 1530 assessed relationships. Our results show that environmental inequalities are a prevalent phenomenon in the city of Santiago, but the details of these inequalities are highly scale dependent. Changing the grain size and extent of analysis do not only affect the strength of relationships between socio-demographic and environmental variables, but also the spatial distribution of environmental inequalities across the urban landscape. Therefore, due to the scale-dependence of assessment results, researchers and decision-makers should be extremely careful when interpreting their findings and translating them into policy making. If the scale dependency of environmental inequalities is not taken into account, policy interventions may be largely ineffective because the scale at which interventions are designed may not match the scale at which inequalities are generated.  相似文献   

3.
Environmental justice is both a vocabulary for political opportunity, mobilization and action, and a policy principle to guide public decision making. It emerged initially in the US, and more recently in the UK, as a new vocabulary underpinning action by community organizations campaigning against environmental injustices. However, as the environmental justice discourse has matured, it has become increasingly evident that it should play a role in the wider agendas for sustainable development and social inclusion. The links between sustainability and environmental justice are becoming clearer and more widely understood in the UK by NGOs and government alike, and it is the potential synergy between these two discourses which is the focus of this paper. This paper argues that the concept of 'just sustainability' provides a discourse for policymakers and activists, which brings together the key dimensions of both environmental justice and sustainable development.  相似文献   

4.
环境公正研究关注人民生活质量的空间公正问题。从环境经济地理学的角度,本研究以广州市为研究对象,采用1995年、2004年、2013 年的工业企业数据和1990年、2000 年、2010 年的人口普查数据,运用空间可视化工具和多尺度地理加权回归模型等方法,分析了广州市污染企业的分布及其与区域人口社会特征关系的时空变化,然后探讨转型背景下中国城市污染企业分布的环境公正问题。研究发现,广州市污染企业空间分布经历由中心城区集聚向近郊区和边界地带集聚的过程,在城市产业空间重构与社会空间分异的共同作用下,污染企业空间分布的环境不公正问题由最初表现不明显转变为全市范围的阶层差异与企业污染负担之间关系,具有不同于西方环境不公正现象的特征和成因。  相似文献   

5.
Quantitative environmental justice (EJ) research has relied on aggregated data from census units to determine disproportionate hazard exposure. Additionally, variables typically used to analyze ethnic inequities in exposure (e.g., percent Hispanic) are too broad and assume a degree of homogeneity that may not exist, given the diversity of ethnic minority populations. We address these limitations through a study that utilizes primary household level survey data and cancer risk estimates from the National-Scale Air Toxics Assessment (NATA) to analyze intra-ethnic inequities in exposure to vehicular air pollutants in the Miami metropolitan area, Florida. Our analysis disaggregates the Hispanic category based on five characteristics (language proficiency, U.S. citizenship, nativity, unemployment status, and national origin) and finds that risk burdens are significantly higher for Hispanic respondents who are foreign-born, unemployed, and of Cuban origin. Findings highlight the advantages of downscaling EJ analyses to the household level and considering intra-ethnic heterogeneity in EJ research and policy.  相似文献   

6.
This study assessed spatial context and the local impacts of putative factors on the proportion of prostate cancer diagnosed at late-stages in Florida during the period 2001–2007. A logistic regression was performed aspatially and by geographically-weighted regression (GWR) at the nodes of a 5 km spacing grid overlaid over Florida and using all the cancer cases within a radius of 125 km of each node. Variables associated significantly with high percentages of late-stage prostate cancer included having comorbidities, smoking, being Black and living in census tracts with farmhouses. Having private or public insurance, being married or diagnosed in a for-profit facility, as well as living in census tracts with high household income reduced significantly this likelihood. Geographically-weighted regression allowed the identification of areas where the local odds ratio is significantly different from the ratio estimated using aspatial regression (State-level). For example, the local odds ratios for the comorbidity covariates were significantly smaller than the State-level odds ratio in Tallahassee and Pensacola, while they were significantly larger in Palm Beach. This emphasizes the need for local strategies and cancer control interventions to reduce the percentage of prostate cancer diagnosed at late-stages and ultimately eliminate health disparities.  相似文献   

7.
This paper applies a spatial perspective to environmental problems in search for the paths to sustainability, using polluting plant relocation in China as a case study. It examines how environmental improvement in one place may lead to environmental degradation in another place, how geographic concepts such as location, distance, spread and backwash effects, and land use models can help understand such phenomenon, and what the implications are for the environmental Kuznets curve (EKC) and development policies. Field research was conducted from 2006 to 2012 in Chinese cities of Beijing, Dalian, Shanghai, Guangzhou, Wuxi, Hangzhou, and Ningbo. It involved intensive site observations and in-depth interviews with government officials of environmental protection, economic development, and business recruitment, and grassroots environmentalists. The results indicate that environmental improvement in all these cities has led to environmental degradation in their suburbs and rural areas due to relocation of polluting plants. Environmental spread and backwash effects may help explain the severe intra-regional environmental and economic disparities and environmental injustice. The powerful and wealthy may achieve rapid economic growth and environmental recovery at the expenses of the powerless and poor, leading to environmental poverty and sustainability disparities.  相似文献   

8.
Regional environmental evaluation often requires a large amount of spatial information. Remote sensing (RS) and geographic information systems (GIS) are capable of managing large amounts of spatially related datum, and providing the ability to integrate multiple layers and to derive additional information. A methodological reference framework, using RS, GIS, and AHP (the analytic hierarchy process), is developed for environmental vulnerability assessment. Using this proposed method, we carried out a case study in the Tibetan Plateau. An environmental vulnerability index (EVI) proposed incorporates 15 factors covering natural conditions, environmental issues, and human activities. According to the EVI values, the vulnerability was classified into five levels: slight (EVI<2.2), light (2.2EVI<2.7), moderate (2.7EVI<3.0), heavy (3.0EVI3.4), and extreme vulnerability (>3.4). The case study showed that the majority of the area in the Tibetan Plateau is ecologically lightly (light level; 22% of the total area), moderately (moderate level; 27%), and heavily (heavy level; 30%) vulnerable. Except for a clearly horizontal distribution, the environmental vulnerability increased clearly with increasing elevation (vertical distribution). The case study verified the usefulness and feasibility of the methods developed, for the results gained reflect the reality of the Tibetan environment closely. Further use in other regions should pay attention to what factors seem to be important in determining the local environmental vulnerability, and how is the impact of each factor on the complex environment.  相似文献   

9.
The concerns of political ecology since its beginnings as a field have been predominantly set in rural areas with limited focus on urban industrial risks. Further, debates on the global South (often from Anglo‐American perspectives) have not fully appreciated the divergent and differentiated perceptions of urban risks and, therefore, everyday forms of resistance within civil society. Instead, work has mainly focused on civil society power relations against the state and industry that are driven by coherent populist political agendas. Against this setting, this paper's contribution aims to better contextualize ‘other’ third world localities in political ecology through a case study of urban industrial risks in the upper/middle income (as opposed to rural, low/lower middle income) country, South Africa. In doing so, the paper sheds light on the derelict aspect of civil society contestation, especially along class and ethnic lines, over urban landfill infrastructure as a livelihood resource or a health hazard. The paper draws upon frameworks of self‐reflexivity and reflexive localism as complementary to the mainstream political ecology to illuminate differentiated civil society reflexiveness and therefore, aims to advance the discussion of other political ecologies. The case study of the largest formal landfill site in Africa, the Bisasar landfill situated in Durban, highlights differences underlying power relations and constraints within civil society (in leadership, social networking, resources and mistrust) that have implications for mainstream political ecology notions of civil society coherence.  相似文献   

10.
This article comprehensively explores the effects of socio-economic status on residents' fresh food access in Saskatoon and Regina, Saskatchewan, Canada. Spatial effects potentially resulting from agglomeration of food retailers and clustering of neighborhoods with similar characteristics have been integrated into analysis using spatial regression models. Key findings include: areas with a larger percentage of population density, single-parent households, senior populations, higher educational populations, and minority groups tend to have higher access to supermarkets and local grocery stores, although the effects vary by city. Areas with higher private car access are more inclined to be farther from these food retailers, meanwhile the influence of public transportation is found to be insignificant in both cities. Regression results demonstrate that ignoring spatial interaction leads to overestimates of the true disparities when investigating food-access inequality among residents with different socio-economic status.  相似文献   

11.
The combined effects of two global trends, urbanization and climate change, have generated considerable concern regarding their adverse and disproportionate impacts on the health of urban populations. This study contributes to climate‐justice research by determining whether elevated levels of urban heat, indicated by land surface temperature (LST), are distributed inequitably with respect to race/ethnicity, age, and socioeconomic status in Pinellas County, Florida. Our study utilizes 2010 MODIS and Landsat medium‐resolution, remotely sensed thermal data, census socio‐demographic information, and both conventional and spatial statistical methods. Results indicate that LST is significantly greater in census tracts characterized by higher percentages of certain racial/ethnic minorities and higher poverty rates, even after controlling for contextual factors and the effects of spatial autocorrelation. This reveals the presence of a landscape of thermal inequity: uneven distribution of heat within the built urban environment and a community structure with varying vulnerability.  相似文献   

12.
Hypotheses based on a set of socio-economic, cultural, and political functional units are examined. The geographic techniques employed in the study include spatial mean, standard distance, standard deviational ellipse, nearest neighbor analysis, and spatial analysis on a network: cross K function and network cross K function. The study not only explores the spatial pattern, distribution, and association of key socio-economic, cultural, and political units which could reveal internal structures and activities of an urban system, but also demonstrates a number of operational procedures that permit applications of traditional and advanced spatial analysis approaches in the study of real urban systems.  相似文献   

13.
The spatial inequality of foreign direct investment (FDI) can intensify uneven economic development. As globalization and economic transition proceeds, foreign investors are changing their behaviors in FDI location, based on institutional change and agglomeration effects. In order to reduce the inequality, this research employs spatial statistics and analyses to examine the change in the spatial inequality of FDI among regions and among prefectural cities, and uses regression models and spatial regime analyses to investigate factors influencing the inequality from 1990 to 2010. The spatial diffusion of FDI clusters from the eastern/coastal region to the interior shows the trend of FDI convergence among regions. However, increasing numbers of FDI clusters and hot spots show the increasing divergence among cities within three regions. Agglomeration effects have replaced institutional factors to become one of the most significant factors influencing the FDI inequality among cities. Additionally, special economic zones, coastal open cities, provincial capital cities, and development zones lost their advantages in FDI as more reforms set in. The spatial regime analyses further indicate the significance of market size in FDI in prefecture-level cities and the significance of agglomeration economies in FDI in capitals and municipalities.  相似文献   

14.
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   

15.
Nathan Frey 《Urban geography》2017,38(10):1534-1549
This study examines equity issues in access to urban environmental amenities using Washington, D.C. as a case study. The amenities that are the focus of this study, urban trees and urban parks, have a range of social and health benefits for city dwellers, and Washington, D.C. is a major city with a large, diverse population and long-standing geographic divisions by race and class. Using spatial regression techniques, the study examines disparities in access to these amenities by race, ethnicity, and socioeconomic status at citywide and sub-city scales. Mixed evidence is found for disparities in access across amenities and across scales. The results emphasize the need for studies of access to urban environmental amenities to pay closer attention to the differences between amenities and to issues of scale.  相似文献   

16.
GIS-based proximity models are one of the key tools for the assessment of exposure to air pollution when the density of spatial monitoring stations is sparse. Central to exposure assessment that utilizes proximity models is the ‘exposure intensity–distance’ hypothesis. A major weakness in the application of this hypothesis is that it does not account for the Gaussian processes that are at the core of the physical mechanisms inherent in the dispersion of air pollutants.

Building upon the utility of spatial proximity models and the theoretical reliability of Gaussian dispersion processes of air pollutants, this study puts forward a novel Gaussian weighting function-aided proximity model (GWFPM). The study area and data set for this work consisted of transport-related emission sources of PM2.5 in the Houston-Baytown-Sugar Land metropolitan area. Performance of the GWFPM was validated by comparing on-site observed PM2.5 concentrations with results from classical ordinary kriging (OK) interpolation and a robust emission-weighted proximity model (EWPM). Results show that the fitting R2 between possible exposure intensity calculated by GWFPM and observed PM2.5 concentrations was 0.67. A variety of statistical evidence (i.e., bias, root mean square error [RMSE], mean absolute error [MAE], and correlation coefficient) confirmed that GWFPM outperformed OK and EWPM in estimating annual PM2.5 concentrations for all monitoring sites. These results indicate that a GWFPM utilizing the physical dispersing mechanisms integrated may more effectively characterize annual-scale exposure than traditional models. Using GWFPM, receptors’ exposure to air pollution can be assessed with sufficient accuracy, even in those areas with a low density of monitoring sites. These results may be of use to public health and planning officials in a more accurate assessment of the annual exposure risk to a population, especially in areas where monitoring sites are sparse.  相似文献   


17.
Natural resource-management studies have become increasingly attentive to the influences of human factors. Among these,cultural biases shape people's responses to changes in natural resource systems. Several studies have applied grid-group cultural theory to assess the effects of multiple value biases among stakeholders on natural resource management. We developed and administered a questionnaire in the Heihe River Basin(n = 364) in northwestern China to investigate the appropriateness of applying this theory in the Chinese context of natural resource management. The results revealed various cultural biases among the respondents. In descending order of prevalence, these biases were hierarchism(46.98%), individualism(26.65%), egalitarianism(18.96%), and fatalism(2.78%), with the remaining respondents(4.67%) evidencing no obvious bias. Our empirical study revealed respondents' worldviews and the influence of sociodemographic characteristics on cultural biases, as theoretically posited. Among the variables examined, age had a positive and significant effect across all biases except individualism. The correlation of income to all cultural biases was consistently negative. Only education had a negative and significant effect across all biases. Women were found to adhere to egalitarianism, whereas men adhered to individualism and hierarchism. Thus, grid-group cultural theory was found to be appropriate in the Chinese context, with gender, age, education, and income evidently accounting for cultural biases. Relationships between environmental attitudes and cultural biases conformed with the hypothesis advanced by grid-group cultural theory. This finding may be of value in explaining individuals' environmental attitudes and facilitating the development and implementation of natural resource-management policies.  相似文献   

18.
区域规划环境评价的空间特性决定其对空间尺度的敏感性。本文从理论层面对区域规划环评中空间尺度与基础数据的关系、空间尺度与显著环境因子识别以及评价指标体系的关系、空间尺度与大气环境影响预测的关系进行了初步探讨。并以"上海高桥镇区域规划环境影响评价"(2005年)和"上海浦东新区国民经济与社会发展规划战略环境评价"(2010年)为例,通过对比方法,进一步说明空间尺度与显著环境因子识别和评价指标体系以及与环境影响预测的关系。结果表明:基础数据收集、汇总是区域规划环评中极为重要的环节,由于不同类型的基础数据表现出不同的空间特征,需要根据评价区域的实际和评价要求,合理选择数据所涵盖的空间范围和空间分辨率。区域规划环境评价应根据本身的层次、涉及范围,筛选出合理的显著环境因子,并建立相应的评价指标体系。大尺度上环境空气质量预测评价的结果侧重于总体描述、解释污染物散布的宏观空间格局和趋势,而在小尺度上则更有利于揭示局地精细化的污染扩散规律。  相似文献   

19.
Rapid channel erosion in the Rio Puerco watershed of northwest New Mexico has been attributed to land use, climate changes, and internal channel adjustments. The objectives of this study were to assess (1) the impacts of land uses on sediment load, (2) the quantitative relationships between land use and sediment load, and (3) the effectiveness of different erosion control methods. The impacts of land uses on sediment load were assessed via hypotheses that, holding other erosion-related variables constant, sediment load correlates positively with grazing intensity and with density of unpaved roads, and correlates negatively with the number of erosion control treatments. We calculated the average annual sediment load for 17 subbasins of 0.67–17.97 km2 by comparing sediment accumulation at two points in time (mid-1960s and 1999) behind intact sediment retention structures. We assessed land use via grazing records and measurements of unpaved roads generated from aerial photographs. Soil characteristics, vegetation, and physical factors were quantified for each subbasin. Using 18 variables for each subbasin, we employed Mallow's Cp as a selection criterion. We used six statistical models, including multiple regression and principal components analysis, to determine inherent mathematical relationships between significant independent variables and sediment load. The results indicate that sediment load does not correlate with grazing intensity except in small, relatively low-relief basins with fewer bedrock exposures. However, this interpretation may be compromised by the low quality of data available to quantify grazing. Sediment load is highly sensitive to the presence of unpaved roads, which serve as high gradient, channelized conduits of water and sediment during storms. Sediment load does not correlate with erosion control except in the subset of small, relatively low-relief subbasins that also proved sensitive to grazing intensity. Overall, the statistical analyses suggest that the impact of land uses on sediment load can be assessed using the data available although physical factors appear more significant than land use in producing high sediment loads in the Rio Puerco subbasins. Historical erosion control techniques, as implemented in the Rio Puerco watershed, prove largely ineffective against accelerated sediment loads because they have not been appropriately implemented or maintained.  相似文献   

20.
恢复效果评估是湿地恢复工程评价以及湿地后续高效管理和利用的基础。以西宁湟水国家湿地公园为案例区,构建基于生态系统特征-生态系统过程-生态系统服务(ECPS)的评估体系,筛选与区域自然环境相适应的的评价因子,采用样方调查、野外监测、问卷调查等方法获取评估数据,从时空尺度评价湿地恢复区植被特征、水文过程到生态系统服务变化情况,并对影响湿地恢复的主要过程和因素展开分析和讨论。结果显示,湿地恢复的综合评价指数为41分,湿地恢复效果较好:① 湿地恢复区植物增加了11种,而湿地植被的平均盖度也增加了35.5%,重点监测的三种优势湿地植物(芦苇、小香蒲和篦齿眼子菜)在单位面积上的平均生物量较参照区平均增加30.9%。② 从生态过程指标来看,湿地恢复区TSIp (Total System Interflow of P)指数和FCIp (Finn Cycle Index of P)指数较参照区分别提升了37.2%和26.3%,说明湿地物质交换和循环过程有一定的改善。③ 从生态系统服务指标的变化来看,栖息地、土壤肥力、水质净化、大气调节、休闲娱乐服务分别增加了92.3%,50.9%,98.3%,73.8%和82.6%。④ 从湿地恢复的影响因素来看,湿地水深、水域面积、水温和底泥颗粒粒径大小与湿地植被恢复相关,并进一步影响湿地生态过程恢复和生态系统服务的空间分布。  相似文献   

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