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111.
In the last two decades, the Portuguese Government has responded to the decline of centres of commerce. In this paper, we analyse the three different experiences of town centre management (TCM) schemes developed in Portugal since the turn of the millennium. The first two stages were developed using public sector initiatives and their impacts were limited. The third stage is still under way and is composed of private projects created by local business owners. Taking Lisbon as a case study for this third stage we conclude that these projects have become a pro-active means of intervention in Portuguese town centres.  相似文献   
112.
113.
Urban Ecosystems - The Andes region is one of the fastest urbanizing regions of the world. The current rate of environmental degradation of streams in this region create an urgent need for...  相似文献   
114.
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   
115.
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   
116.
Afforestation is inserted in the urban environment and interferes directly in the surface runoff. In order to quantify the rainfall interception by tree species, an experiment was carried out in the city of Uruaçu, Goiás, Brazil, with the four most common tree species in the urban afforestation of the region. The species chosen were the Mangifera indica (mango tree), the Caesalpinia peltophoroides (sibipiruna tree), the Pachira aquatica (munguba tree) and the Licania tomentosa (oiti). In order to register precipitation, ten pluviographs were used. They are capable of measuring precipitation over time in terms of duration, volume, and intensity. For events with a mean cumulative precipitation of 16.7 mm, the mean values of interception found in each species were: Mangifera indica - 8.0 mm; Pachira aquatica - 7.4 mm; Licania tomentosa - 7.2 mm; and Caesalpinia peltophoroides - 4.8 mm. The research confirms the importance of studies related to the identification of the species’ individual characteristics that interfere in the rainfall interception capacity and that can consequently contribute to urban drainage actions. In addition, it proves the existence of variations of rainfall interception in relation to rainfall events and during their occurrences and emphasizes the need for a careful definition of the species that will compose the urban afforestation.  相似文献   
117.
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   
118.
McClung  Teegan  Ibáñez  Inés 《Urban Ecosystems》2018,21(1):147-155
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   
119.
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   
120.
This article provides an exploratory analysis of the life narratives of migrants in the Portuguese-speaking world. By interweaving the life experiences of eight participants in three thematic clusters – ‘shared past’, language and sense of community – we propose a critique of the deep-seated idea of the Lusophone space as a community constructed by the harmonious conviviality of different countries and people. Drawing on contributions from cultural studies, social psychology, anthropology and sociology, we first aim to give voice to the human subjects who embark on migrations and then to understand how the engendered process of identity construction is framed by their social world, simultaneously reframing it. Thus, we aim at shedding light on the ways in which aspects of the political discourses on Lusophony are used (and are instrumental) to the migrants’ identity narrative (re)construction.  相似文献   
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