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Rainfall interception by Santa Monica's municipal urban forest   总被引:4,自引:2,他引:2  
Effects of urban forests on rainfall interception and runoff reduction have been conceptualized, but not well quantified. In this study rainfall interception by street and park trees in Santa Monica, California is simulated. A mass and energy balance rainfall interception model is used to simulate rainfall interception processes (e.g., gross precipitation, free throughfall, canopy drip, stemflow, and evaporation). Annual rainfall interception by the 29,299 street and park trees was 193,168 m3 (6.6 m3/tree), or 1.6% of total precipitation. The annual value of avoided stormwater treatment and flood control costs associated with reduced runoff was $110,890 ($3.60/tree). Interception rate varied with tree species and sizes. Rainfall interception ranged from 15.3% (0.8 m3/tree) for a small Jacaranda mimosifolia (3.5 cm diameter at breast height) to 66.5% (20.8 m3/tree) for a mature Tristania conferta (38.1 cm). In a 25-year storm, interception by all street and park trees was 12,139.5 m3 (0.4%), each tree yielding $0.60 (0.4 m3/tree) in avoided flood control costs. Rainfall interception varied seasonally, averaging 14.8% during a 21.7 mm winter storm and 79.5% during a 20.3 mm summer storm for a large, deciduous Platanus acerifolia tree. Effects of differences in temporal precipitation patterns, tree population traits, and pruning practices on interception in Santa Monica, Modesto, and Sacramento, California are described.  相似文献   
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Tree health is a critical parameter for evaluating urban ecosystem health and sustainability. Traditionally, this parameter has been derived from field surveys. We used multispectral remote sensing data and GIS techniques to determine tree health at the University of California, Davis. The study area (363 ha) contained 8,962 trees of 215 species. Tree health conditions were mapped for each physiognomic type at two scales: pixel and whole tree. At the pixel scale, each tree pixel within the tree crown was classified as either healthy or unhealthy based on vegetation index values. At the whole tree scale, raster based statistical analysis was used to calculate tree health index which is the ratio of healthy pixels to entire tree pixels within the tree crown. The tree was classified as healthy if the index was greater than 70%. Accuracy was checked against a random sample of 1,186 trees. At the whole tree level, 86% of campus trees were classified as healthy with 88% mapping accuracy. At the pixel level, 86% of the campus tree cover was classified as healthy. This tree health evaluation approach allows managers to identify the location of unhealthy trees for further diagnosis and treatment. It can be used to track the spread of disease and monitor seasonal or annual changes in tree health. Also, it provides tree health information that is fundamental to modeling and analysis of the environmental, social, and economic services produced by urban forests.  相似文献   
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The current study assesses ageism and heterosexism relating to older adult sexual activity within long-term care facilities. To assess caregiver reactions, 153 residential care facility staff members read one of three vignettes. Each vignette described a scenario in which a staff member walks in on two residents (male/female, male/male, or female/female) engaging in sexual activity. Although no main effects were discovered for vignette type, exploratory analyses revealed that the facility where participants were employed was significantly related to their ratings of approval. Furthermore, an interaction effect between vignette and facility types was also discovered for caregivers’ approval of sexual activity among residents. Additionally, a strong overall approval rating of older adult sexuality was reported by staff members. The results of this study warrant that further research is necessary regarding older adults’ perception of caregiver bias, as well as further investigation of caregivers’ perceptions of older adults’ sexual activity.  相似文献   
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A significant proportion of young people in Australia are currently not being engaged in school and other social systems. This article presents the results of a mixed-methods study of a pilot Family Wellbeing intervention designed to enhance the social and emotional wellbeing (SEWB) of young Aboriginal men and improve engagement in education, employment, and other social participation. A questionnaire incorporating the Kessler Psychological Distress Scale and respondent self-assessment SEWB questions was administered to program participants pre and post intervention (N = 30) and qualitative data were collected from program organisers (N = 6). The results suggest that the Family Wellbeing intervention has the capacity to make a marked contribution to the SEWB of young Aboriginal men; participants experienced strong improvement in capacity to manage relationships, engagement in education and employment, and mental and physical health. The factors that enabled the program to be adapted to the target group and setting are documented.  相似文献   
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Child and family practice and child protection are extraordinarily complex. They require in-depth understanding of intra- and inter-personal skills and intricate service systems, and capacity to operate in a constantly changing policy environment. One way of meeting the needs of such practitioners is facilitating their access to experts working across direct practice, management and leadership and policy-making contexts. This article discusses the rationale for collaboratively delivered post-qualifying courses for child and family practitioners, and discusses a highly successful example of such courses delivered through La Trobe University. It outlines the unique developmental process and model of delivery adopted by the consortium responsible for the postgraduate programme. It concludes with reference to early evaluative findings indicating it as a promising pedagogical model.  相似文献   
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This paper explores the potential of observational sketching as a social science research tool, informed by our own recent experiments with observational sketching techniques and approaches. We first outline the historical roots of academic sketching and note a recent resurgence of interest in sketching in certain disciplines. We then introduce our own explorations in sketching as method, based on a year-long collaboration between an observational artist and a group of qualitative researchers with interests in creative methods. The paper outlines some of the lessons we learnt from our partnership, focusing on three themes: (i) ‘sketchiness’; (ii) ‘concentrated seeing’ and (iii) sketching as interaction. We conclude that observational sketching generates a refreshingly different form of visual data which has considerable potential to be used as a complement to other methods, including as a participatory method and as a useful tool for thinking.  相似文献   
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One in five college women experience sexual victimization (SV), and SV severity is associated with subsequent psychological distress, including sex-related distress. SV severity may also be associated with drinking motives to cope with sex-related distress and to enhance sex (sex-related drinking motives [SRDMs]), particularly if individuals suffer from emotion regulation (ER) difficulties. College women (N = 151) completed a survey assessment of ER, SV history, childhood sexual abuse (CSA), and SRDMs. Twelve regression models assessed six facets of ER as moderators between SV severity and SRDMs. Among women with no or low levels of prior SV severity, women with greater access to ER strategies were less likely to endorse drinking to cope SRDMs. At higher levels of SV severity, women at all levels of access to ER strategies were equally likely to endorse drinking to cope SRDMs, suggesting that access to ER strategies did not mitigate motivations to drink to cope with sex-related distress for these women. Women with severe SV histories may benefit from interventions that build on existing ER strengths or address other factors. However, greater access to ER strategies may serve as a protective factor against SRDMs when SV severity is low.  相似文献   
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This paper further tests dual interest theory and the metaeconomics approach to environmental choice, recognizing a possible role for empathy–sympathy (the basis for an internalized, shared other-interest) in tempering and conditioning the more fundamental tendency to pursue self-interest. To test, we focus on rivers flowing through agricultural areas carrying sediments, chemicals, and fertilizers which are making their way into downstream rivers and lakes. We conduct a framed laboratory experiment modeling this problem: farmers decide on the usage of conservation technology to lessen impacts on the water quality (i.e. on the commons, the capacity to absorb these wastes) in downstream areas, which is more costly than the alternative intensive technology. The results confirm our hypotheses, demonstrating that Upstream Farmers who practice conservation are tempering profit maximization with empathy-based, environmentally conscious behavior. Such behavior better serves the farmers’ own-interest, and also helps Downstream Water Users. Environmental economics models need to explicitly include empathy–sympathy and the moral–ethical context it produces, providing a more scientific basis for conservation policy and programs.  相似文献   
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