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1.
Glob Chang Biol ; 29(12): 3271-3284, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36924241

RESUMO

At large scales, the mechanisms underpinning stability in natural communities may vary in importance due to changes in species composition, mean abundance, and species richness. Here we link species characteristics (niche positions) and community characteristics (richness and abundance) to evaluate the importance of stability mechanisms in 156 butterfly communities monitored across three European countries and spanning five bioclimatic regions. We construct niche-based hierarchical structural Bayesian models to explain first differences in abundance, population stability, and species richness between the countries, and then explore how these factors impact community stability both directly and indirectly (via synchrony and population stability). Species richness was partially explained by the position of a site relative to the niches of the species pool, and species near the centre of their niche had higher average population stability. The differences in mean abundance, population stability, and species richness then influenced how much variation in community stability they explained across the countries. We found, using variance partitioning, that community stability in Finnish communities was most influenced by community abundance, whereas this aspect was unimportant in Spain with species synchrony explaining most variation; the UK was somewhat intermediate with both factors explaining variation. Across all countries, the diversity-stability relationship was indirect with species richness reducing synchrony which increased community stability, with no direct effects of species richness. Our results suggest that in natural communities, biogeographical variation observed in key drivers of stability, such as population abundance and species richness, leads to community stability being limited by different factors and that this can partially be explained due to the niche characteristics of the European butterfly assemblage.


Assuntos
Borboletas , Ecossistema , Animais , Biodiversidade , Teorema de Bayes , Europa (Continente)
2.
Commun Biol ; 5(1): 143, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177761

RESUMO

Climatic anomalies are increasing in intensity and frequency due to rapid rates of global change, leading to increased extinction risk for many species. The impacts of anomalies are likely to vary between species due to different degrees of sensitivity and extents of local adaptation. Here, we used long-term butterfly monitoring data of 143 species across six European bioclimatic regions to show how species' population dynamics have responded to local or globally-calculated climatic anomalies, and how species attributes mediate these responses. Contrary to expectations, degree of apparent local adaptation, estimated from the relative population sensitivity to local versus global anomalies, showed no associations with species mobility or reproductive rate but did contain a strong phylogenetic signal. The existence of phylogenetically-patterned local adaptation to climate has important implications for forecasting species responses to current and future climatic conditions and for developing appropriate conservation practices.


Assuntos
Adaptação Fisiológica/genética , Borboletas/genética , Borboletas/fisiologia , Clima , Ecossistema , Filogenia , Distribuição Animal , Animais , Simulação por Computador , Europa (Continente) , Filogeografia
3.
Ecol Evol ; 11(23): 16434-16445, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34938447

RESUMO

Trait and functional trait approaches have revolutionized ecology improving our understanding of community assembly, species coexistence, and biodiversity loss. Focusing on traits promotes comparability across spatial and organizational scales, but terms must be used consistently. While several papers have offered definitions, it remains unclear how ecologists operationalize "trait" and "functional trait" terms. Here, we evaluate how researchers and the published literatures use these terms and explore differences among subdisciplines and study systems (taxa and biome). By conducting both a survey and a literature review, we test the hypothesis that ecologists' working definition of "trait" is adapted or altered when confronting the realities of collecting, analyzing and presenting data. From 486 survey responses and 712 reviewed papers, we identified inconsistencies in the understanding and use of terminology among researchers, but also limited inclusion of definitions within the published literature. Discrepancies were not explained by subdiscipline, system of study, or respondent characteristics, suggesting there could be an inconsistent understanding even among those working in related topics. Consistencies among survey responses included the use of morphological, phonological, and physiological traits. Previous studies have called for unification of terminology; yet, our study shows that proposed definitions are not consistently used or accepted. Sources of disagreement include trait heritability, defining and interpreting function, and dealing with organisms in which individuals are not clearly recognizable. We discuss and offer guidelines for overcoming these disagreements. The diversity of life on Earth means traits can represent different features that can be measured and reported in different ways, and thus, narrow definitions that work for one system will fail in others. We recommend ecologists embrace the breadth of biodiversity using a simplified definition of "trait" more consistent with its common use. Trait-based approaches will be most powerful if we accept that traits are at least as diverse as trait ecologists.

4.
Animals (Basel) ; 10(8)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785203

RESUMO

The pressure elicited by invasive species on native species significantly increases with the increase of the overlap of their ecological niches. Still, the specific mechanisms of the trophic displacement of native species during the invasion process are unclear. The effects of the invasive American mink (Neovison vison) on the critically endangered European mink (Mustela lutreola) was assessed by analyses of diet and niche overlap during the invasion process. To do this, the isotopic composition (δ13C and δ15N) of both species of mink and their four main types of prey was analysed. Significant trophic overlap between the native European mink and invasive American mink was found when they coexisted in sympatry. Furthermore, both mink species were characterised by significant individual variation in diet and no obvious change in diet of the native species in response to the arrival of the introduced species was observed. High niche overlap registered between both species in sympatry with no displacement in diet of the native mink in response to the arrival of the invasive mink is expected to have important consequences for the viability and conservation of the native mink populations, as it suggests high competitive pressure.

5.
J Environ Manage ; 265: 110497, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32292169

RESUMO

Against a backdrop of accelerating digital innovation in nature conservation and environmental management, a real-world experiment was conducted with the research aims of assessing: 1) the effects of introducing a digital data-entry platform on volunteer data submission; and 2) the extent to which coordinators influence digital platform use by their volunteers. We focussed on a large-scale volunteer-based initiative aimed at eradicating the non-native American mink (Neovison vison) from northern Scotland. This geographically dispersed conservation initiative adopted a digital platform that allowed volunteers to submit records to a central database. We found that the platform had a direct and positive effect on volunteer data submission behaviour, increasing both the number and frequency of submissions. However, our analysis revealed striking differences in coordinator engagement with the platform, which in turn influenced the engagement of volunteers with this centrally introduced digital innovation. As a consequence, the intended organisation-wide rolling out of a digital platform translated into a diversely-implemented innovation, limiting the efficacy of the tool and revealing key challenges for digital innovation in geographically-dispersed conservation initiatives.


Assuntos
Conservação dos Recursos Naturais , Voluntários , Humanos , Escócia
6.
Sci Total Environ ; 674: 603-614, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31026792

RESUMO

The aim of this paper is to test two methodologies, applicable to different spatial scales (from regional to local), to predict the capacity of agroecosystems to provide habitats for the species richness of butterflies and birds, based on the ways their socio-metabolic flows change the ecological functionality of bio-cultural landscapes. First, we use the more general Intermediate Disturbance-Complexity (IDC) model to assess how different levels of human appropriation of photosynthetic production affect the landscape functional structure that hosts biodiversity. Second, we apply a more detailed Energy-Landscape Integrated Analysis (ELIA) model that focusses on the energy storage carried out by the internal biomass loops, and the energy information held in the network of energy flows driven by farmers, in order to correlate both (the energy reinvested and redistributed) with the energy imprinted in the landscape patterns and processes that sustain biodiversity. The results obtained after applying both models in the province and the metropolitan region of Barcelona support the Margalef's energy-information-structure hypothesis by showing positive relations between butterflies' species richness, IDC and ELIA, and between birds' species richness and energy information. Our findings support the view that strong relationships between farming energy flows, agroecosystem functioning and biodiversity can be detected, and highlight the importance of farmers' knowledge and labour to maintain bio-cultural landscapes.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental , Agricultura , Animais , Biodiversidade , Aves , Borboletas , Ecossistema , Fazendas , Humanos
7.
Sci Total Environ ; 569-570: 1013-1021, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27387798

RESUMO

Anticoagulant rodenticides (ARs) are highly toxic compounds that are exclusively used for the control of rodent pests. Despite their defined use, they are nonetheless found in a large number of non-target species indicating widespread penetration of wildlife. Attempts to quantify the scale of problem are complicated by non-random sampling of individuals tested for AR contamination. The American mink (Neovison vison) is a wide ranging, non-native, generalist predator that is subject to wide scale control efforts in the UK. Exposure to eight ARs was determined in 99 mink trapped in NE Scotland, most of which were of known age. A high percentage (79%) of the animals had detectable residues of at least one AR, and more than 50% of the positive animals had two or more ARs. The most frequently detected compound was bromadiolone (75% of all animals tested), followed by difenacoum (53% of all mink), coumatetralyl (22%) and brodifacoum (9%). The probability of mink exposure to ARs increased by 4.5% per month of life, and was 1.7 times higher for mink caught in areas with a high, as opposed to a low, density of farms. The number of AR compounds acquired also increased with age and with farm density. No evidence was found for sexual differences in the concentration and number of ARs. The wide niche and dietary overlap of mink with several native carnivore species, and the fact that American mink are culled for conservation throughout Europe, suggest that this species may act as a sentinel species, and the application of these data to other native carnivores is discussed.


Assuntos
Exposição Ambiental , Espécies Introduzidas , Vison/metabolismo , Rodenticidas/metabolismo , Espécies Sentinelas/metabolismo , Animais , Anticoagulantes/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Feminino , Masculino , Escócia
8.
Cir. Esp. (Ed. impr.) ; 92(6): 404-409, jun.-jul. 2014. tab
Artigo em Espanhol | IBECS | ID: ibc-124835

RESUMO

INTRODUCCIÓN: El objetivo del estudio es observar la evolución psicológica en un grupo de pacientes intervenidos mediante gastrectomía vertical laparoscópica (GVL) y tras un año de seguimiento multidisciplinar. MÉTODOS: Un total de 46 pacientes con un IMC de 35 o superior completaron las pruebas psicológicas antes de la cirugía, y volvieron a cumplimentar dichas pruebas al año de la GVL (tras un seguimiento médico, nutricional y psicológico). RESULTADOS: Se observó una mejoría en todas las escalas analizadas, excepto el perfeccionismo. Los cambios más significativos se refieren al área de sintomatología alimentaria, con una mejora del 89% en bulimia (p < 0,01), y un 55% en insatisfacción corporal (p < 0,01) e ineficacia (p < 0,01). Por otra parte, en el área de calidad de vida cabe destacar una mejoría del 57% en el cambio de salud (p < 0,01). CONCLUSIÓN: La GVL con un seguimiento multidisciplinar se confirma como una intervención efectiva para mejorar los síntomas bulímicos y la calidad de vida. Estos resultados son similares a los recogidos en diferentes estudios con bypass gástrico, y no tanto a otros con gastroplastia vertical anillada y banda gástrica ajustable. Sin embargo, son necesarios estudios a largo plazo para confirmar esta tendencia


BACKGROUND: The aim of this study is to observe the psychological changes at one-year postop in a group of patients undergoing laparoscopic vertical sleeve gastrectomy (GVL) and multidisciplinary follow-up. METHODS: A total of 46 patients with a BMI-35 or higher, who were selected for GVL, completed psychological testing. After GVL surgery, patients received psychological, nutritional, and medical attention during 12 months, and they retook the same tests. RESULTS: Psychological tests showed an improvement on almost all scales tested, except perfectionism. The most significant change was in the benchmark for Eating Disorders with an improvement of 89% for bulimia (P<.01), and 55% for body dissatisfaction (P<.01) and ineffectiveness (P<.01). In quality of life there was an improvement of 57% in the change in health status (P<.01). CONCLUSION: During our study, a protocol involving GVL and multidisciplinary follow-ups proved to be an effective intervention for improving bulimic symptoms and quality of living. The results of these psychological changes are similar to Roux-en-Y Gastric bypass but different to vertical banded gastroplasty or adjustable gastric band, according to previous studies. However, long-term studies are necessary to confirm this trend


Assuntos
Humanos , Obesidade Mórbida/psicologia , Cirurgia Bariátrica/psicologia , Redução de Peso , Obesidade Mórbida/cirurgia , Qualidade de Vida/psicologia , Bulimia/epidemiologia , Autoimagem , Imagem Corporal , Psicometria/instrumentação
9.
Cir Esp ; 92(6): 404-9, 2014.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-24447872

RESUMO

BACKGROUND: The aim of this study is to observe the psychological changes at one year postop in a group of patients undergoing laparoscopic vertical sleeve gastrectomy (GVL) and multidisciplinary follow- up. METHODS: A total of 46 patients with a BMI-35 or higher, who were selected for GVL, completed psychological testing. After GVL surgery, patients received psychological, nutritional, and medical attention during 12 months, and they retook the same tests. RESULTS: Psychological tests showed an improvement on almost all scales tested, except perfectionism. The most significant change was in the benchmark for Eating Disorders with an improvement of 89% for bulimia (P<.01), and 55% for body dissatisfaction (P<.01) and ineffectiveness (P<.01). In quality of life there was an improvement of 57% in the change in health status (P<.01). CONCLUSION: During our study, a protocol involving GVL and multidisciplinary follow-ups seems proved to be an effective intervention for improving bulimic symptoms and quality of living. The results of these psychological changes are similar to Roux-en-Y Gastric bypass but different to vertical banded gastroplasty or adjustable gastric band, according to previous studies. However, long-term studies are necessary to confirm this trend.


Assuntos
Gastroplastia/psicologia , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Adulto , Feminino , Seguimentos , Gastroplastia/métodos , Humanos , Laparoscopia , Masculino , Inquéritos e Questionários
10.
Oecologia ; 174(2): 427-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24065555

RESUMO

Trophic relationships between invasive species in multiply invaded ecosystems may reduce food limitation relative to more pristine ecosystems and increase resilience to control. Here, we consider whether invasive predatory American mink Neovison vison are trophically subsidized by invasive crayfish. We collated data from the literature on density and home range size of mink populations in relation to the prevalence of crayfish in the diet of mink. We then tested the hypothesis that populations of an invasive predator reach higher densities and are more resilient to lethal control when they have access to super-abundant non-native prey, even in the absence of changes in density dependence, hence compensatory capacity. We found a strong positive relationship between the proportion of crayfish in mink diet and mink population density, and a negative relationship between the proportion of crayfish in mink diet and mink home range size, with crayfish contribution to mink diet reflecting their abundance in the ecosystem. We then explored the consequence of elevated mink density by simulating a hypothetical eradication program with a constant harvest in a Ricker model. We found that mink populations were more resilient to harvest in the presence of crayfish. As a result, the simulated number of mink harvested to achieve eradication increased by 500% in the presence of abundant crayfish if carrying capacity increased by 630%. This led to a threefold increase in time to eradication under a constant harvest and an approximately 20-fold increase in the cumulative management cost. Our results add to evidence of inter-specific positive interactions involving invasive species, and our simple model illustrates how this increases management cost.


Assuntos
Astacoidea , Cadeia Alimentar , Espécies Introduzidas , Vison , Animais , Conservação dos Recursos Naturais , Modelos Biológicos , Densidade Demográfica , Dinâmica Populacional , Comportamento Predatório
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