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1.
PLoS One ; 13(12): e0208718, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30557407

RESUMO

Policy-makers require strategies to select a set of sustainability indicators that are useful for monitoring sustainability. For this reason, we have developed a model where sustainability indicators compete for the attention of society. This model has shown to have steady situations where a set of sustainability indicators are stable. To understand the role of the network configuration, in this paper we analyze the network properties of the Entangled Sustainability model. We have used the degree distribution, the clustering coefficient, and the interaction strength distribution as main measures. We also analyze the network properties for scenarios compared against randomly generated scenarios. We found that the stable situations show different characteristics from the unstable transitions present in the model. We also found that the complex emergent feature of sustainability shown in the model is an attribute of the scenarios, however, the randomly generated scenarios do not present the same network properties.


Assuntos
Modelos Teóricos , Desenvolvimento Sustentável , Algoritmos , Simulação por Computador , Humanos , Crescimento Sustentável
2.
PLoS One ; 13(11): e0206672, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383800

RESUMO

Interactions between people and ecological systems, through leisure or tourism activities, form a complex socio-ecological spatial network. The analysis of the benefits people derive from their interactions with nature-also referred to as cultural ecosystem services (CES)-enables a better understanding of these socio-ecological systems. In the age of information, the increasing availability of large social media databases enables a better understanding of complex socio-ecological interactions at an unprecedented spatio-temporal resolution. Within this context, we model and analyze these interactions based on information extracted from geotagged photographs embedded into a multiscale socio-ecological network. We apply this approach to 16 case study sites in Europe using a social media database (Flickr) containing more than 150,000 validated and classified photographs. After evaluating the representativeness of the network, we investigate the impact of visitors' origin on the distribution of socio-ecological interactions at different scales. First at a global scale, we develop a spatial measure of attractiveness and use this to identify four groups of sites. Then, at a local scale, we explore how the distance traveled by the users to reach a site affects the way they interact with this site in space and time. The approach developed here, integrating social media data into a network-based framework, offers a new way of visualizing and modeling interactions between humans and landscapes. Results provide valuable insights for understanding relationships between social demands for CES and the places of their realization, thus allowing for the development of more efficient conservation and planning strategies.


Assuntos
Ecossistema , Modelos Teóricos , Mídias Sociais , Adulto , Conservação dos Recursos Naturais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fotografação , Fatores Socioeconômicos , Análise Espacial , Viagem
3.
Sci Total Environ ; 579: 1215-1227, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27919556

RESUMO

In this paper, we reflect on the implications for science, policy and practice of the recently introduced concept of Nature-Based Solutions (NBS), with a focus on the European context. First, we analyse NBS in relation to similar concepts, and reflect on its relationship to sustainability as an overarching framework. From this, we derive a set of questions to be addressed and propose a general framework for how these might be addressed in NBS projects by funders, researchers, policy-makers and practitioners. We conclude that: To realise their full potential, NBS must be developed by including the experience of all relevant stakeholders such that 'solutions' contribute to achieving all dimensions of sustainability. As NBS are developed, we must also moderate the expectations placed on them since the precedent provided by other initiatives whose aim was to manage nature sustainably demonstrates that we should not expect NBS to be cheap and easy, at least not in the short-term.


Assuntos
Ecologia , Política Ambiental , Conservação dos Recursos Naturais/métodos , Ecossistema , Europa (Continente)
4.
Parasitol Int ; 65(2): 163-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26620805

RESUMO

The recent identification of Pseudamphistomum truncatum, (Rudolphi, 1819) (Trematoda: Opisthorchiidae) and Metorchis bilis (Braun, 1790) Odening, 1962 (synonymous with Metorchis albidus (Braun, 1893) Loos, 1899 and Metorchis crassiusculus (Rudolphi, 1809) Looss, 1899 (Trematoda: Opisthorchiidae)) in otters from Britain caused concern because of associated biliary damage, coupled with speculation over their alien status. Here, we investigate the presence, intensity and phylogeny of these trematodes in mustelids (principally otters) across Europe (Czech Republic, Denmark, France, Germany, Norway, Poland and Sweden and Britain). The trematodes were identified to species using the internal transcribed spacer II (ITS2) locus. Both parasites were found across Europe but at unequal frequency. In the German state of Saxony, eight out of eleven (73%) otters examined were infected with P. truncatum whilst this parasite was not found in either mink from Scotland (n=40) or otters from Norway (n=21). Differences in the phylogenies between the two species suggest divergent demographic histories possibly reflecting contrasting host diet or competitive exclusion, with M. bilis exhibiting greater mitochondrial diversity than P. truncatum. Shared haplotypes within the ranges of both parasite species probably reflect relatively unrestricted movements (both natural and anthropogenic) of intermediate and definitive hosts across Europe.


Assuntos
Vison/parasitologia , Lontras/parasitologia , Trematódeos/genética , Trematódeos/isolamento & purificação , Infecções por Trematódeos/veterinária , Animais , Europa (Continente)/epidemiologia , França/epidemiologia , Fluxo Gênico , Alemanha/epidemiologia , Haplótipos , Espécies Introduzidas , Mitocôndrias/genética , Filogenia , Polônia/epidemiologia , Trematódeos/classificação , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia , Reino Unido
5.
Environ Sci Technol ; 47(20): 11757-65, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24033312

RESUMO

Liver samples from 140 otters (Lutra lutra) from Sweden and Norway were analyzed for 10 perfluoroalkyl carboxylic acids (PFCAs; C6-C15), 4 perfluoroalkane sulfonic acids (PFSAs; C4,C6,C8,C10) and perfluorooctane sulfonamide (FOSA). Perfluorooctane sulfonic acid (PFOS) was the dominant compound accounting for approximately 80% of the fluorinated contaminants and showing concentrations up to 16 µg/g wet weight. Perfluorononanoic acid (PFNA) was the dominant PFCA (up to 640 ng/g wet weight) closely followed by the C10 and C11 homologues. A spatial comparison between otters from southwestern Norway, southern and northern Sweden sampled between 2005 and 2011 revealed that the samples from southern Sweden had generally the largest contaminant load, but two PFCAs and FOSA were higher concentrated in the Norwegian samples. A temporal trend study was performed on otters from southern Sweden collected between 1972 and 2011. Seven PFCAs (C8-C14), PFOS and perfluorodecane sulfonic acid (PFDS) showed significantly increasing trends with doubling times between 5.5 and 13 years. The PFCAs also showed significantly increasing trends over the period 2002 to 2011. These findings together with the exceptionally high liver concentrations of PFOS are of great concern for the Scandinavian otter populations.


Assuntos
Espécies em Perigo de Extinção , Monitoramento Ambiental , Fluorocarbonos/análise , Lontras/metabolismo , Ácidos Alcanossulfônicos/análise , Animais , Ácidos Graxos , Modelos Lineares , Fígado/metabolismo , Noruega , Suécia , Fatores de Tempo
6.
J Anim Ecol ; 77(6): 1183-90, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18657209

RESUMO

1. Wolves Canis lupus L. recolonized the boreal forests in the southern part of the Scandinavian peninsula during the late 1990s, but so far there has been little attention to its effect on ecosystem functioning. Wolf predation increases the availability of carcasses of large prey, especially moose Alces alces L., which may lead in turn to a diet switch in facultative scavengers such as the wolverine Gulo gulo L. 2. Using 459 wolverine scats collected during winter-spring 2001-04 for DNA identity and dietary contents, we compared diet inside and outside wolf territories while controlling for potential confounding factors, such as prey density. We tested the hypothesis that wolverine diet shifted towards moose in the presence of wolves, while taking into account possible sexual segregation between the sexes. Occurrence of reindeer, moose and small prey was modelled against explanatory covariates using logistic mixed-effects models. Furthermore, we compared diet composition and breadth among habitats and sexes. 3. Occurrence of reindeer, moose and small prey in the diet varied with prey availability and habitat. As expected, diet contained more moose and less reindeer and small prey in the presence of wolves. Their diet in tundra consisted of 40% reindeer Rangifer tarandus L., 39% moose and 9% rodents. In forest with wolf, their diet shifted to 76% moose, 18% reindeer and 5% rodents; compared to 42% moose, 32% reindeer and 15% rodents in forest without wolf. This diet switch could not be explained by higher moose density in wolf territories. Female diet consisted of more small prey than for males, but there was a tendency for females to use the highly available moose carrion opportunistically and to hunt less on small prey within wolf territories. 4. Our study highlights how wolves increase scavenging opportunities for wolverines, and how sexual differences in diet may also apply to large scavengers. Due to their more restricted home range, female wolverines are forced to rely more on hunting small prey. The relatively high occurrence of wolf kills, however, forms an important food source to wolverines in this area. The recolonization of wolves may therefore have contributed to the consequent recolonization of wolverines into the same area.


Assuntos
Dieta , Comportamento Alimentar/fisiologia , Mustelidae/fisiologia , Lobos/fisiologia , Animais , Cervos , Ecossistema , Feminino , Masculino , Roedores , Países Escandinavos e Nórdicos
7.
J Appl Ecol ; 45(5): 1382-1391, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19330031

RESUMO

The re-establishment of large carnivores in Norway has led to increased conflicts and the adoption of regional zoning for these predators. When planning the future distribution of large carnivores, it is important to consider details of their potential habitat tolerances and strength of inter-specific differentiation. We studied differentiation in habitat and kill sites within the large-carnivore community of south-eastern Norway.We compared habitat selection of the brown bear Ursus arctos L., Eurasian lynx Lynx lynx L., wolf Canis lupus L. and wolverine Gulo gulo L., based on radio-tracking data. Differences in kill site locations were explored using locations of documented predator-killed sheep Ovis aries L. We modelled each species' selection for, and differentiation in, habitat and kill sites on a landscape scale using resource selection functions and multinomial logistic regression. Based on projected probability of occurrence maps, we estimated continuous patches of habitat within the study area.Although bears, lynx, wolves and wolverines had overlapping distributions, we found a clear differentiation for all four species in both habitat and kill sites. The presence of bears, wolves and lynx was generally associated with rugged, forested areas at lower elevations, whereas wolverines selected rugged terrain at higher elevations. Some degree of sympatry was possible in over 40% of the study area, although only 1.5% could hold all four large carnivores together.Synthesis and applications. A geographically differentiated management policy has been adopted in Norway, aimed at conserving viable populations of large carnivores while minimizing the potential for conflicts. Sympatry of all four carnivores will be most successful if regional zones are established of adequate size spanning an elevational gradient. High prey densities, low carnivore densities, low dietary overlap and scavenging opportunities have most probably led to reduced competitive exclusion. Although regional sympatry enhances the conservation of an intact guild of large carnivores, it may well increase conflict levels and resistance to carnivore conservation locally.

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