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91.
Landscape urbanization threatens plant phylogenetic diversity in the Brazilian Atlantic Forest 总被引:1,自引:0,他引:1
Valdecir Silva-Junior Danielle G. Souza Rubens T. Queiroz Luiz G. R. Souza Elâine M. S. Ribeiro Bráulio A. Santos 《Urban Ecosystems》2018,21(4):625-634
Urbanization causes species loss around the world, but its effects on phylogenetic diversity are poorly known in tropical forests. Using a patch-landscape approach in an urbanizing region of the Brazilian Atlantic Forest, we tested whether the increase in landscape urbanization reduces plant species density, phylogenetic richness and divergence, and increases the relatedness among co-occurring individuals and species. We assessed plant responses to urbanization in adult (diameter at breast height?>?10 cm) and sapling communities (2.5–10 cm diameter) separately, as saplings are proxies of the future flora. We sampled 2860 woody plants belonging to 155 species in nine circular landscapes with urbanization level varying from 0% to 45%, and estimated the relatedness among the species that have increased and decreased in relative abundance in more urbanized landscapes (winner and losers, respectively). As expected, species density and phylogenetic richness decreased with the increase in urbanization. These responses were consistent for adult and sapling communities, suggesting a persistent loss of species and lineages in more urbanized landscapes. Contrary to our expectations, phylogenetic divergence and structure did not respond to urbanization, indicating that the more urbanized landscapes still retain much evolutionary history. However, because the relatedness among winners was greater than among losers, it is likely that the phylogenetic divergence gradually reduces and the relatedness increases, resulting in impoverished forests with uncertain ability to provide ecosystem services such as carbon storage and pest control. This environmental cost should be taken into account to align urban sprawl with biodiversity conservation. 相似文献
92.
Improving and measuring transparency in NGOs: A disclosure index for activities and projects 下载免费PDF全文
J. David Cabedo Iluminada Fuertes‐Fuertes Amparo Maset‐LLaudes José Miguel Tirado‐Beltrán 《Nonprofit management & leadership》2018,28(3):329-348
Nongovernmental organizations (NGOs) are established not with the aim of making profits but rather to provide social values by implementing different projects and activities. Transmitting complete information about these projects to society is a key element of transparency, as they operate within an atmosphere of public trust. Although there is a large body of literature on transparency in NGOs from a global perspective, very little research has been conducted on transparency within the area of projects and activities. This study takes a deeper look at this line and contributes to the literature on transparency in NGOs by proposing an index to measure the information transparency of the projects implemented by these organizations. The index captures three dimensions of the information about the projects (technical, financial, and scope) and makes it possible to: analyze the level of transparency of the portfolio of projects, detect the specific aspects that could be improved in each organization, and carry out comparisons among organizations. 相似文献
93.
Joaquín Castillo de Mesa María de las Olas Palma García Luis Gómez Jacinto 《European Journal of Social Work》2018,21(6):902-915
ABSTRACTSocial network services are allowing more social connectivity and making possible sharing information and knowledge of a different nature. This article analyses if social workers related to active social policies from Malaga province (Spain) are using social network services to share information and knowledge and if there is a mirror between online and offline relationships. Since it is an experimental model, through virtual ethnography and through social network analysis methodology, we observed the presence, connectivity and analysed the structure of relationships that keep 235 professionals from 52 organizations in Facebook®. Moreover, the model uses the statistical technique of modularity for detecting online communities, which are compared with distribution of professionals in their organizations. Results show how social network services applied to social intervention are massively and frequently used by professionals. On the other hand, the detected communities reflect existence of analogy between online and offline relationships. The online structure shows a high degree of cohesion and how certain professionals have higher capacity of influence and diffusion depending on position in the online structure. It argues about the opportunity to incorporate social network services towards social intervention as a manner of social innovation to improve cooperation and diffusion of information and knowledge. 相似文献
94.
Ríos-Chelén Alejandro Ariel Cuatianquiz-Lima Cecilia Bautista Amando Martínez-Gómez Margarita 《Urban Ecosystems》2018,21(1):15-25
Urban Ecosystems - Vermilion flycatchers, a suboscine, sing songs with more elements in territories with higher urban noise levels. We tested the hypothesis that this pattern is achieved through... 相似文献
95.
Urban Ecosystems - The global trend of increasing urbanization is generating isolated patches of vegetation that could be strongly influenced by the surrounding landscape. Simultaneously, many of... 相似文献
96.
Ferenc Michal Sedláček Ondřej Fuchs Roman Hořák David Storchová Lenka Fraissinet Maurizio Storch David 《Urban Ecosystems》2018,21(2):369-377
Urban Ecosystems - Urban bird communities are homogenized across large spatial scales, suggesting that the urban environment acts as an environmental filter. We hypothesize that large scale... 相似文献
97.
María del Mar Gálvez-Rodríguez Arturo Haro-de-Rosario 《Information, Communication & Society》2018,21(10):1402-1418
The role of community manager is gaining importance as the proper usage of social media becomes a key factor for achieving more active involvement of citizens in social and political issues. Focused on Spanish local governments and in line with the literature of Excellence Theory, this paper aims to analyze whether some characteristics of the community manager function are determinant in their fostering of citizens’ online engagement via social media. In particular ‘independence’, ‘having access to the dominant coalition’, ‘gender diversity’, ‘continuous training’ and ‘culture of the organization’ are the characteristics considered in this paper. As to the main findings, this study confirms that community managers have not as yet achieved their goal of embedding the use of social media by citizens as a means of establishing more direct contact with their local governments. Moreover, in line with Excellence Theory, community managers of local governments should be aware of the importance of having direct access to key managers of the organization in order to better achieve the objectives of the organization and, more specifically, to increase citizens’ engagement. Furthermore, continuous training in issues related to social media truly helps develop the skills and potential of community managers. Likewise, an excellent communication department should rely on good professionals no matter their gender, and, in this sense, the gender of community managers is not a significant factor in their performance. However, the results of this study also reveal that in the case of public sector community managers, an authoritarian culture seems to be a determining factor for obtaining better results in enhancing citizens’ engagement. 相似文献
98.
Zdeněk Hlávka Marie Hušková Claudia Kirch Simos G. Meintanis 《Econometric Reviews》2017,36(4):468-492
We develop testing procedures which detect if the observed time series is a martingale difference sequence. Furthermore, tests are developed that detect change–points in the conditional expectation of the series given its past. The test statistics are formulated following the approach of Fourier–type conditional expectations first proposed by Bierens (1982) and have the advantage of computational simplicity. The limit behavior of the test statistics is investigated under the null hypothesis as well as under alternatives. Since the asymptotic null distribution contains unknown parameters, a bootstrap procedure is proposed in order to actually perform the test. The performance of the bootstrap version of the test is compared in finite samples with other methods for the same problem. A real–data application is also included. 相似文献
99.
Bráulio M. Veloso Thais R. Correa Marcos O. Prates Gabriel F. Oliveira Andréa I. Tavares 《Statistics and Computing》2017,27(4):1099-1110
Crime or disease surveillance commonly rely in space-time clustering methods to identify emerging patterns. The goal is to detect spatial-temporal clusters as soon as possible after its occurrence and to control the rate of false alarms. With this in mind, a spatio-temporal multiple cluster detection method was developed as an extension of a previous proposal based on a spatial version of the Shiryaev–Roberts statistic. Besides the capability of multiple cluster detection, the method have less input parameter than the previous proposal making its use more intuitive to practitioners. To evaluate the new methodology a simulation study is performed in several scenarios and enlighten many advantages of the proposed method. Finally, we present a case study to a crime data-set in Belo Horizonte, Brazil. 相似文献
100.
This article evaluates the pension policy pathways of the 11 former state socialist nations that have joined the European Union since 2004. Focusing primarily on the post‐2004 period, the analysis discusses the most important measurable outcomes of these countries’ pension reforms, in terms of poverty alleviation, pension adequacy and fiscal sustainability. Going beyond the quantifiable concepts, we also investigate the quality of the 11 countries’ pension systems in terms of equity as well as efficiency, emphasizing the less conspicuous design errors present in these systems. Although these errors have received little attention to date, they may harm pension schemes along several dimensions, including their fiscal sustainability. 相似文献