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851.
Species that successfully inhabit urban ecosystems are rare, and urbanisation often drives localised extinctions of native species. Nonetheless, some species take advantage of the novel conditions available in cities and increase in abundance. Trends in the abundance and distribution of species in urban areas have received much attention, but the precise elements of urban ecosystems that affect the survival of urban-dwelling species are largely unknown. Animals that successfully exploit urban environments may do so because of increases in the availability of resources or habitats. Here we assess the effects of anthropogenic landscapes and prey abundance on the persistence of an orb-weaving spider, Nephila plumipes. We assessed spider persistence for six months in situ along an urban gradient in Sydney. We then transplanted spiders from a common garden into sites along the gradient, monitored their persistence in the new environment and measured a suite of environmental variables at local and landscape scales. The abundance of prey was closely linked with spider persistence, in both the survey and the transplant experiment, and was positively associated with anthropogenic habitats. The surveyed spiders survived longer when located closer to the coast and transplanted spiders persisted longer in smaller sites with more impervious surfaces and reduced vegetation cover. Our study shows that urbanisation has a strong effect on potential prey abundance and can lead to increased persistence of N. plumipes, demonstrating the broad impacts that habitat disturbance can have on the life history and trophic interactions of city-dwelling animals. 相似文献
852.
The environmental factors affecting the spatial dynamics of bird communities in urban parks are well understood, but much less attention has been paid to the seasonal dynamics of bird communities. Since migrant and resident human commensal birds might have contrasting responses to environmental factors of urban parks, we expected different seasonal dynamics among parks. On the other hand, because bird species can have different habitat relationships throughout the year, we also expected different responses of bird richness to environmental variables between breeding and non-breeding seasons. Bird surveys were conducted in 14 small urban parks (1–4 Ha) of Mar del Plata city (Argentina) for one full annual cycle. Bird richness changed between seasons, but bird abundance remained constant. Bird community composition did not vary between seasons, but urban parks near the urban center, with the highest pedestrian traffic and isolation to other green areas had the least seasonal change of composition. During the breeding season, bird richness was negatively affected by the percentage cover of high buildings surrounding the immediate limits of parks, whereas during the non-breeding season bird richness was not related with any environmental variable. Bird composition variation among parks was affected by the distance to the urban center during both seasons. Results showed that urbanization promotes a seasonal homogenization of bird communities in urban parks, probably by affecting the presence of migrant species and promoting the temporal stability of human commensal species. 相似文献
853.
ABSTRACTMaking informed financial decisions is crucial to the wellbeing of Chinese migrant workers. Using interview survey data (N = 329), this study examined financial knowledge and behaviors of migrant workers in China. Results showed that participants demonstrated low levels of financial knowledge (51.4%) and beneficial financial behaviors (51.0%). Multivariate results indicated that a modest proportion of the variance in financial behaviors was explained by financial knowledge, attitudes, and socio-demographic characteristics (e.g., marital status and income). Findings underscore the importance of disseminating culturally-relevant educational interventions to financially at-risk, low-paid migrant workers in China. 相似文献
854.
Irga Peter J. Burchett Margaret D. O’Reilly Gabe Torpy Fraser R. 《Urban Ecosystems》2016,19(2):885-898
Urban Ecosystems - Many street trees in urban areas are deciduous and drop leaves during autumn. These leaves are a potential growing substrate for fungi, which when aerosolized and inhaled, can... 相似文献
855.
This study assessed social skills in post-institutionalized (PI) children with respect to age at adoption, age at assessment, and gender. Parent ratings of social skills (Social Skills Rating System) and behavior problems (Child Behavior Checklist) were obtained for 214 children and 127 adolescents who were adopted from socially-emotionally depriving Russian institutions. Results showed that children adopted before 18 months of age have better social skills than those adopted after this age; those assessed in childhood demonstrate better social skills than those assessed in adolescence. PI females, especially later-adopted adolescents, have particularly poor social skills. Children with poor social skills tend to have higher rates of behavior problems. 相似文献
856.
Cross-sectional research on internationally adopted children has indicated an association between early attachment disturbances and language deficits. Raaska et al. (2013) have speculated that this relationship is likely bidirectional. In an attempt to elucidate the causal relationship between these two risk factors, the attachment disturbances and language skills of 44 internationally adopted children were assessed in a cross-lagged structural equation model. Greater attachment disturbances at wave 1 predicted less gain in language by wave 2. In contrast, language at wave 1 was not predictive of attachment disturbances at wave 2. These results suggest that early attachment problems may present an important risk for later language development and should be an immediate and primary focus of post-adoptive intervention for families adopting internationally. 相似文献
857.
858.
Fiona M. Brooks Kayleigh L. Chester Nigel C. Smeeton Neil H. Spencer 《Journal of youth studies》2016,19(1):36-54
The geographies of the current generation of young people are markedly distinct from previous generations by virtue of their access to a virtual playground. The vast majority of young people now engage in video gaming as a leisure activity. Drawing on findings from the 2009/2010 WHO Health Behaviour in School-aged Children study this paper set out to investigate the factors that might be associated with higher levels of video gaming. Information was collected from 4404 school students aged 11, 13 and 15 years, using anonymised self-completed questionnaires. Higher usage was defined as game play exceeding two hours a day. Separate analyses were conducted for boys and girls. For both genders higher levels of game playing was associated with early adolescence, opposite sex friends and minimal parental mediation. Bullying and going to bed hungry were associated with higher usage for boys only, while life satisfaction and family activities were linked to girls’ game playing only. Parents were identified as effective mediators of young people’s video game usage. The study identified gendered motivations for higher levels of game play, suggesting different interventions for boys and girls may be required in order for young people to create a balanced approach to video gaming. 相似文献
859.
Peter Hart 《Journal of youth studies》2016,19(7):869-884
‘Professional boundaries’ set limits on appropriate behaviours in the relationship between the service users and practitioners. The professional literature often assumes boundaries are maintained by the practitioners, occupational bodies, or organisational policy. However in youth work this is under-researched. An ethnographic study of four youth clubs in the North East of England into ethical practice revealed that young people were surprisingly adept at maintaining boundaries with the youth workers. These boundaries were negotiated and maintained through the young people's use of space, their willingness to interact with the workers, the way they shared information with the workers, and their inclusion of youth workers into their social networking. Young people also showed a sophisticated awareness of the organisational boundaries youth workers were operating within, and often cooperated in maintaining them with the worker. The article concludes by arguing youth workers should take seriously young people's ability and willingness to set and work within boundaries, and see their negotiation and maintenance as a mutual endeavour. However, this may provide a challenge to organisations with rigid policy-defined boundaries. 相似文献
860.
Andrea M. Collins 《International Feminist Journal of Politics》2016,18(4):559-573
Amidst global concern over the state of transnational large-scale agricultural investments, several efforts have been made to set global standards for “responsible agricultural investment.” While these efforts have received mixed reviews from the international community, very little attention has been paid to the gendered language of these principles. Through examining two separate sets of agricultural investment principles – one created by the United Nations Food and Agriculture Organization (FAO), the United Nations Conference on Trade and Development, the International Fund for Agricultural Development and the World Bank, and the other by the United Nations Committee on World Food Security – this article finds that, despite different processes and participants in the creation of these principles, they nonetheless share a language of “empowerment” targeted at women and marginalized groups. However, in contrast to early feminist discourses of empowerment, these principles instead perpetuate the notion that empowerment is to be found through efficiency, productivity and participation in land and labor markets. This article takes a critical look at this language of economic empowerment in each set of principles, and points to the dangers of equating efficiency, productivity and participation with feminist empowerment. By not acknowledging the broader gender dynamics of agricultural governance and markets, these discourses risk deepening existing inequalities rather than moving toward meaningful social change. 相似文献