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911.
S. T. A. Pickett M. L. Cadenasso E. J. Rosi-Marshall K. T. Belt P. M. Groffman J. M. Grove E. G. Irwin S. S. Kaushal S. L. LaDeau C. H. Nilon C. M. Swan P. S. Warren 《Urban Ecosystems》2017,20(1):1-14
Urban areas are understood to be extraordinarily spatially heterogeneous. Spatial heterogeneity, and its causes, consequences, and changes, are central to ecological science. The social sciences and urban design and planning professions also include spatial heterogeneity as a key concern. However, urban ecology, as a pursuit that integrates across these disciplines, lacks a theoretical framework that synthesizes the diverse and important aspects of heterogeneity. This paper presents the concept of dynamic heterogeneity as a tool to explore how social and ecological heterogeneities interact and how they together act as both an outcome of past interactions and a driver future heterogeneity and system functions. To accomplish this goal, we relate heterogeneity to the fundamental concept of the human ecosystem. The human ecosystem concept identifies key processes that require operationalized models of dynamic heterogeneity in three process realms: the flow of materials, the assembly of urban ecosystem biota, and the locational choices humans make concerning land. We exemplify a specific dynamic model of heterogeneity in each of these realms, and indicate a range of complementary statistical approaches to integrate the drivers and outcomes of dynamic heterogeneity across the three realms. We synthesize a hierarchical framework for a theory of dynamic urban heterogeneity, noting its complementarity to other major urban theories and general model approaches. We hypothesize that human actions and structures amplify the dynamics of heterogeneity in urban systems. 相似文献
912.
Soil nitrogen (N) mineralization is an important process determining terrestrial N availability, and evidence suggests elevated temperatures will enhance N mineralization rates. Along a 40 km urban-rural gradient of chestnut oak forest stands in Louisville, KY, we expected N mineralization rates would be higher in urban than in rural forests in part due to increased temperatures caused by the urban heat island. However, a 12-month field study along this Louisville gradient showed that annual N mineralization rates were lower in urban than in rural stands. Since variation in precipitation inputs and other factors across this land-use gradient may be influencing soil N mineralization rates, we conducted a three-month soil incubation experiment in the lab to determine the extent to which a + 2 °C temperature difference could affect soil N mineralization in urban and rural soils. Across the range of temperatures tested, rural soils mineralized N at twice the rate of urban soils under base (7.86 vs. 3.65 mg N kg?1 AFDW soil d?1) and elevated (9.08 vs. 4.76 mg N kg?1 AFDW soil d?1) temperatures (p < 0.01). A 2 °C temperature difference, did not significantly alter total inorganic N production in urban (p = 0.272) or rural soils (p = 0.293). The proportion of nitrate produced was lower in the urban (15.1 %) than in the rural soils (72.3 %; p < 0.01). These results suggest that differences in soil organic matter quality and potentially decomposer community composition are the primary explanatory factors for forests along this Louisville gradient. 相似文献
913.
Getting closure: The role of urban forest canopy density in moderating summer surface temperatures in a large city 总被引:1,自引:0,他引:1
With a growing number of people living in urban areas, city residents are more frequently exposed to stresses related to the built environment including elevated summer surface temperatures contributing to the urban heat island (UHI) effect. This study examines the role of urban tree density in moderating surface temperature variation in a densely populated city (Toronto, Canada). By applying parallel aspatial (OLS) and spatial regression (GWR) approaches with satellite derived data describing tree canopy density and surface temperature, one dimension of tree canopy quality (i.e., canopy density) is shown to contribute directly to a reduction in the surface urban heat island (SUHI) effect at a local scale. Though the model fit differed between the two regression approaches, both exhibited moderately strong explanatory power and demonstrated that observed surface temperature decreases in locations with increasing high-density and closed tree canopy. Study findings provide an empirical basis to recommend that municipal urban forest strategies embrace canopy quality metrics, such as increasing the density of existing urban forest stands, as a part of tree planting objectives seeking to effectively deliver temperature moderation as a valuable ecosystem service. 相似文献
914.
ABSTRACTThe article analyses the politics of ‘double discourse’ in relation to Roma that has evolved in contemporary neoliberal Europe. On the one hand, the double discourse promotes the integration, rights and equal opportunities of Roma, on the other, it denies recognition of, and ways to address, enduring structural violence and rising social insecurity. The article argues that the politics of ‘double discourse’, as a neoliberal approach towards Roma, is structured by two contradictory discourses that speak to different audiences, using duplicitous approaches to create anti-Roma consensus and maintain the critical difference and subordinated position of the racialised Romani populations in Europe. By studying the representation of Roma in the cases of so-called 'child theft' in Greece and Ireland, and in the recent ‘refugee crisis’, the paper identifies and discusses three dimensions of contemporary neoliberal double discourse: racialised de-Europeanisation, neoliberal undeservingness and (dis)articulation of citizenship. 相似文献
915.
K.G. Nijhoff M.C. Gordano 《Innovation: The European Journal of Social Science Research》2017,30(2):182-203
This paper echoes the need to further explore the social effects of European Union integration by examining the increasingly complex and diverse scenario of intra-European mobility. Much research has focused on the intensification of East-to-West migrant flows after the enlargements of 2004 and 2007, inspiring a rich conceptualization of migrant typologies. Theoretically, this paper argues that some of these typologies can be extrapolated to better understand the experiences of other European movers. Empirically, it offers a qualitative and comparative analysis of diverse European young adults’ experiences of mobility: 8 Polish citizens in The Hague and 10 Spaniards in London. The analysis is based on four main dimensions derived from the literature: (1) Motivations to migrate, (2) Labour market participation, (3) Attachments and transnational ties and (4) Family composition and future outlooks. Results map individual differences and similarities contextualized by generational, gendered, educational and socio-economic aspects. 相似文献
916.
Shanna K. Kattari Angela Lavery Leslie Hasche 《Journal Of Human Behavior In The Social Environment》2017,27(8):865-880
With an estimated 21.3% of persons aged 15 and older experiencing disability in the USA, social workers will see clients present with disabilities across all practice settings and stages of human development. Yet, the training and terminology of social workers—which often closely aligns with medical professionals—may seem to occur in isolating silos or disciplinary theories. Social work education often views the needs of older adults and people with disabilities as two distinct populations, despite the fact that many of these individuals share similar needs for access, resources, and support. Furthermore, when discussing human development, the focus may skew to individual affective, behavioral, and cognitive processes and indicators of abnormal development and frailty. Thus, by clarifying terminology and applying a social model of disability across the life span, we identify how educational efforts related to human behavior and the social environment can promote intersectional and inclusive social work related to aging and disability. 相似文献
917.
K.E. Kushner N. Sopcak R. Breitkreuz N. Pitre D.L. Williamson G. Rempel 《Community, Work & Family》2017,20(2):119-141
We examined first-time fathers’ and mothers’ perspectives about their ideal world of support in the context of dominant social ideology, ethno-cultural ideals, and the pragmatics of their everyday family, workplace, and socioeconomic circumstances during their first 18 months as parents. Twelve Canadian-born and six Chinese immigrant couples participated in individual in-depth interviews. We conducted a three-part analysis: fathers’ perspectives, mothers’ perspectives, and couples’ perspectives. Fathers focused on fulfilling dual fathering ideals of ‘time with family’ and ‘providing for family’; mothers emphasized fulfilling a mothering ideal of ‘caring for children'. Examining couples’ perspectives revealed a more nuanced understanding of their shared focus on ‘caring for family'. Parents in this study found the current social ideal of the ‘new’ father, who is both financial provider and nurturing co-parent, appealing, yet difficult to achieve. Couples wanted informal (i.e. family and social network) support, along with formal (i.e. workplace and childcare) support to enable them to provide family care and financial stability for their family. Findings contribute to understanding family and paid work experiences and decision-making among couples as new parents. We offer insights into the complexity of intersections among social ideals, personal expectations, family care, and paid work for fathers and mothers. 相似文献
918.
S. Cowlishaw 《International Gambling Studies》2017,17(2):343-348
This paper provides a response to the commentary by Delfabbro and King (2017), which describes major criticisms of articles situated in a ‘political economy’ conceptual framework. The current paper argues that these criticisms obfuscate legitimate concerns about industry involvement in gambling research, and disregard important evidence about activities of hazardous-consumption industries which provide grounds for strong concern about commercial practices of the gambling industry. Although many aspects of the commentary by Delfabbro and King (2017) are contentious, the current paper summarizes conceptual and empirical literature which supports concern about (a) agency and collaboration in practices of the gambling industry, which make assertions of equivalence with a conspiracy theory both inappropriate and misleading, and (b) the role of research on problem gambling behaviours and pathologies in supporting agendas that may undermine public health. This indicates the need for the scientific community to take seriously its role in improving awareness of the hazards of commercial involvement in gambling research, and thus helping researchers to make informed decisions about these risks and their own manner of engagement with the gambling industry. 相似文献
919.
Erin K. Wilson 《Globalizations》2017,14(7):1076-1093
AbstractRecent religious studies and international relations scholarship has highlighted secularism as a critical element in dominant modes of identity, power, and exclusion in global politics. Yet, the implications of these insights for global justice theory and practice have rarely been considered. This article suggests that the current dominance of secularism within global justice theory and practice risks undermining the global justice project. Specifically, I argue that secularism’s dominance constitutes an ontological injustice, where both alternative non-secular visions of the world and visions of alternative non-secular worlds are subordinated to secular ontologies. However, this argument raises a crucial question: if, despite secularism’s claim to neutrality and universality, the dominance of secular ontologies contributes to rather than ameliorates injustice, the question that remains is: what are the alternatives? The article concludes by exploring some preliminary responses to this question. 相似文献
920.
Using the eye gaze of others to direct one's own attention develops during the first year of life and is thought to be an important skill for learning and social communication. However, it is currently unclear whether infants differentially attend to and encode objects cued by the eye gaze of individuals within familiar groups (e.g., own race, more familiar sex) relative to unfamiliar groups (e.g., other race, less familiar sex). During gaze cueing, but prior to the presentation of objects, 10‐month‐olds looked longer to the eyes of own‐race faces relative to 5‐month‐olds and relative to the eyes of other‐race faces. After gaze cueing, two objects were presented alongside the face and at both ages, infants looked longer to the uncued objects for faces from the more familiar‐sex and longer to cued objects for the less familiar‐sex faces. Finally, during the test phase, both 5‐ and 10‐month‐old infants looked longer to uncued objects relative to cued objects but only when the objects were cued by an own‐race and familiar‐sex individual. Results demonstrate that infants use face eye gaze differently when the cue comes from someone within a highly experienced group. 相似文献