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61.
A desirable function for terrestrial urban ecosystems is the mitigation of nitrogen (N) pollution associated with cities and suburbs. To assist in maximizing this function, identifying locations of sources and sinks of N in the urban environment is crucial to inform management strategies. Lawns are an extensive land cover in urbanized landscapes, and in general, they have demonstrated the capacity to function as a sink for N inputs. How N is cycled by lawns, however, is likely not uniform across the physical heterogeneity or management activities that exist in lawns. We investigated the influence of heterogeneity in light availability on N cycling in lawns that were irrigated but not fertilized. Light availability is affected by tree canopy and built structures and is, therefore, heterogeneous both within individual lawns and among lawns. Light is expected to control N retention and loss through effects on primary productivity. We experimentally examined N regulation over one calendar year by measuring net primary production (NPP), N retention using an isotopic tracer, and N leaching in existing unfertilized lawns under heterogeneous light conditions. We used a budgetary approach to estimate gaseous N loss which we assume is primarily via denitrification. Light functioned as a limiting resource for primary productivity. From low to high light conditions, annual NPP increased 177 to 430 g C?m?2?y?1 and retention of N isotope tracer increased from 50 to 65% as a result of increased retention in plants. Nitrate leaching losses were low overall and were not affected by light levels. Light availability regulated the fate of N inputs and unfertilized lawns may function as substantial sinks for reactive N through storage in the terrestrial system and N loss by denitrification. However, whether or not denitrification is generally an N sink will depend on the ratio of non-reactive (i.e., N2) to reactive (i.e., N2O, NO) denitrification products. Overall, we find that effective strategies for managing N sources and sinks in cities will likely need to consider light availability, particularly in systems receiving water subsidies via irrigation. 相似文献
62.
Kyle?T.?MartinsEmail author Andrew?Gonzalez Martin?J.?Lechowicz 《Urban Ecosystems》2017,20(6):1359-1371
The role of urban expansion on bee diversity is poorly understood, but it may play an important role in restructuring pollinator diversity observed in rural regions at the urban perimeter. We studied bee communities in two habitats essential for pollinators (residential gardens and semi-natural areas) at 42 sites situated at the edge of greater Montreal, Canada. Bee species richness, abundance and functional diversity all increased with urbanization in both habitat types, but gardens and semi-natural areas supported distinct bee communities with unique responses to urbanization in terms of species turnover. Compared to semi-natural sites, residential gardens supported bees that foraged from a greater number but a lower proportion of available plant species. Bees did not discriminate between exotic and indigenous plant species in either gardens or semi-natural sites and were attracted to flowers in either habitat irrespective of their origins. Protecting semi-natural ruderal areas and providing residential garden habitats for pollinators are both effective means of promoting regional bee diversity in urbanizing regions. 相似文献
63.
64.
The systemic impact of adoption suggests the need to explore adoption-specific curricula in baccalaureate and graduate degree programs. Using a convenience sample, the present exploratory study collected data in two phases. Phase one included email requests for adoption syllabi to professional email lists and to identified faculty with adoption research and practice expertise. In phase two, 22 faculty members who responded by emailing syllabi were invited to participate in an online survey. Results only begin to unveil what we know about adoption-specific curricula in higher education. Suggestions for future research are discussed. 相似文献
65.
The paper focuses on the commodification and politicisation of cultural heritage using as a case study the ongoing debate on the return of the Parthenon Marbles from the U.K. to Greece, recently reignited by the press release for the movie The Monuments Men in 2014. Greece has been in the throes of a severe financial crisis for over six years with the ever imminent threat of Grexit constantly disputed. In parallel with this ongoing turmoil, discourses of Greek antiquity have been persistently prominent in the media. In this context, we problematise the complex nexus of relationships between the financial crisis, national identity and cultural heritage. We combine the Discourse‐Historical Approach and Interactional Sociolinguistics drawing data from an online forum, and investigate how the users negotiate pro‐/anti‐return positions and make the financial crisis relevant in the argumentation process. The analysis shows that history, identity, value, and debt are recontextualised in relation to the Parthenon sculptures. The analysis identifies an underlying process of value trade off and brings the current political and economic environment to the fore. We close the paper by foregrounding the implications of our study and provide directions for further research. 相似文献
66.
Bruno Cardinale Lagomarsino Matías Gutman Lucía Freira María Laura Lanzalot Maximiliano Lauletta Leandro E. Malchik Felipe Montaño Campos Bianca Pacini Martín A. Rossi Christian Valencia 《Economic inquiry》2017,55(3):1579-1584
We provide experimental evidence on the effect of peer pressure on individual behavior. Specifically, we study the effect of being exposed to an observer in a public restroom on handwashing and urinal flushing behavior. Our estimates show that being exposed to an observer increases the probability of handwashing by 13 percentage points and the probability of urinal flushing by 15 percentage points. Given that handwashing and urinal flushing have social benefits that exceed individual benefits, our findings provide support for peer pressure as an additional way of addressing the social suboptimality arising from externalities. (JEL C91, C93) 相似文献
67.
Does the Person‐of‐the‐Therapist Training (POTT) Promote Self‐Care? Personal Gains of MFT Trainees Following POTT: A Retrospective Thematic Analysis 下载免费PDF全文
As we recognize how taxing our profession can be, therapist's self‐care has become a salient topic in mental health. However, we are still discerning how to promote self‐care in our practice and in training. In this paper, we present a study on the personal gains that MFT students experienced after participating in the Person‐of‐the‐Therapist Training (POTT). We propose that the reported changes (better understanding of self, change to self, relational changes, and change as a process) constitute improvements in the trainees’ well‐being, and can therefore be considered self‐caring behaviors and practices. We state that models like POTT, that focus on embracing our vulnerability, can help clinicians be more caring toward ourselves. We conclude this paper by presenting clinical and training recommendations. 相似文献
68.
The way public policies are managed in Brazil has changed since the 1988 Federal Constitution. This study aimed to identify how changes in the structure of public expenditure composition at Brazilian federal states influenced local human development in these states. The states’ public expenditures were categorized according to their nature as spending indices whereas human development was measured through a human development index (HD). To verify the relationships between these variables, an accounting-social theoretical model was created and estimated through latent growth modeling (LGM). The LGM measurement period comprised five administration cycles of the Brazilian states (1988–2011). Variables were measured on data of the second year of state government term; their mean initial values and growth rates were recorded. Results show that, influenced by policies of centralized regulation promoted by the federal government, only the social spending growth rates had statistically significant effect on the human development growth rate, although not considered of great magnitude. Among mean initial values, the most significant was that of minimum spending (SIm), which denotes the direct impact of the Fiscal Accountability Law [Lei de Responsabilidade Fiscal, in Portuguese] on human development improvements. The mean initial value of economic spending also showed a positive and significant effect on HD growth rate. 相似文献
69.
While nature is widely acknowledged to contribute to people’s well-being, nature based well-being indicators at city-level appear to be underprovided. This study aims at filling this gap by introducing a novel indicator based on the proximity of city-residents to nature that is of high-amenity. High-amenity nature is operationalized by combining unique systematic data on people’s perceptions of what are the locations of attractive natural areas with data on natural land cover. The proposed indicator departs from the usual assumption of equal well-being from any nature, as it approximates the ‘actual’ subjective quality of nature near people’s homes in a spatially explicit way. Such indicator is used to rank 148 ‘cities’ in the Netherlands, Denmark, and Germany. International comparability of the indicator is enhanced by the use of a definition of cities as functional urban areas (FUAs), which are consistently identified across countries. Results demonstrate that the average ‘nearness’ of FUA populations to high amenity nature varies widely across the observed FUAs. A key finding, that complements insights from existing city-level indicators, is that while populations of FUAs with higher population densities may live relatively far from nature in general, they also live, on average, closer to high-amenity nature than inhabitants of lower density FUAs. Our results may stimulate policy-debates on how to combine urban agglomeration with access to natural amenities in order to account for people’s wellbeing. 相似文献
70.
Laura?BiniEmail author Francesco?Dainelli Francesco?Giunta 《Journal of Management and Governance》2017,21(1):63-91
This paper offers a contribution to the call for research on the effectiveness of regulatory interventions governing management commentary disclosure. Specifically, we focus on the mandatory requirement concerning performance indicator disclosure introduced by the Modernisation Directive (2003/51/EC). In keeping with other regulators, the European legislator opted to implement a regulatory approach based on a rule with loose specifications. To understand the effects of this Directive, we have investigated the Italian context, in which neither the national legislator nor the standard setter have supported companies with detailed specifications or guidelines aimed at integrating the European provision. We have compared companies’ disclosure practices before and after the adoption of the Directive, investigating the number of disclosed indicators and also their modalities of presentation, as they are considered essential to guaranteeing the quality of this disclosure. Our results document that a mandatory intervention, even if based on loose specifications, is associated with an increase in disclosure practices. Nevertheless, such regulation does not seem able to guarantee high quality disclosure practices. In fact, before and after the regulation, companies primarily disclose common financial measures. Moreover, the usefulness of such disclosure is undermined by a limited compliance with the international guidelines concerning the modalities of presentation. These results reveal some weaknesses in the European approach to performance indicator regulation. In general, the EU legislator fails to explain the purpose and the objective of performance indicator disclosure and does not take into account the differences between financial and non-financial indicators. Furthermore, it does not provide firms with clear guidelines concerning the presentation modalities. 相似文献