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1.
Biodivers Data J ; 11: e110415, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098784

RESUMO

Background: With the increasing recognition of the significance of arachnid conservation, it is crucial to allocate greater efforts towards implementing targeted monitoring programmes. Despite recent studies, our understanding of arachnid populations in Portugal remains limited. This study serves as the initial inventory of arachnids (Araneae and Opiliones) within the Castro Verde Special Protection Area (SPA) located in Beja, southern Portugal. The surveys were conducted during the spring of 2012 across 80 open grasslands that were grazed by cattle and sheep. New information: A total of 71 species of Araneae and two species of Opiliones have been identified. Notably, three spider species, namely Argennasubnigra, Civizelotesibericus and Walckenaeriacucullata, are documented for the first time in Portugal. Additionally, two harvestmen species (Dasylobusibericus and Homalenotusbuchneri) and 14 spider species (Cheiracanthiumpennatum, Haplodrassusrhodanicus, Marinarozelotesminutus, Tapinocybaalgirica, Agraecinalineata, Tibellusmacellus, Talaverapetrensis, Tetragnathaintermedia, Dipoenaumbratilis, Enoplognathadiversa, Neottiurauncinata, Ruborridionmusivum, Theridionpinastri and Xysticusgrallator) are recorded for the first time in the Beja District. The occurrence of each documented species within the SPA, including family and species details, is presented, underscoring the significance of the Castro Verde SPA for arachnid conservation. These findings contribute novel insights into the biodiversity of the Castro Verde SPA, emphasising the necessity of incorporating this area into arachnid diversity conservation efforts.

2.
Agron Sustain Dev ; 43(3): 39, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200584

RESUMO

European farm households will face increasingly challenging conditions in the coming decades due to climate change, as the frequency and severity of extreme weather events rise. This study assesses the complex interrelations between external framework conditions such as climate change or adjustments in the agricultural price and subsidy schemes with farmers' decision-making. As social aspects remain understudied drivers for agricultural decisions, we also consider value-based characteristics of farmers as internal factors relevant for decision-making. We integrate individual learning as response to extreme weather events into an agent-based model that simulates farmers' decision-making. We applied the model to a region in Eastern Austria that already experiences water scarcity and increasing drought risk from climate change and simulated three future scenarios to compare the effects of changes in socio-economic and climatic conditions. In a cross-comparison, we then investigated how farmers can navigate these changes through individual adaptation. The agricultural trajectories project a decline of active farms between -27 and -37% accompanied by a reduction of agricultural area between -20 and -30% until 2053. The results show that regardless of the scenario conditions, adaptation through learning moderates the decline in the number of active farms and farmland compared to scenarios without adaptive learning. However, adaptation increases the workload of farmers. This highlights the need for labor support for farms. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-023-00890-z.

3.
Sci Rep ; 11(1): 10827, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031443

RESUMO

Mediterranean pastures are experiencing strong changes in management, involving shifts from sheep to cattle-based livestock systems. The impacts of such shifts on biodiversity are still poorly understood. Here, we sought to contrast the grazing regime, vegetation structure, bird species richness and abundance, between sheep and cattle grazed parcels, to understand the mechanisms through which management decisions impact farmland birds. During spring 2019, we characterized livestock management, bird populations and sward structure in 23 cattle and 27 sheep grazed parcels. We used a Structural Equation Model to infer the direct and indirect effects of sheep and cattle grazing on birds. Although no effects were found on overall species richness, there were species-specific responses to sheep and cattle grazed systems. Grazing pressure (variable integrating stocking rate and the number of days in the parcel) had negative impacts on the prevalence/abundance of Zitting Cisticola, Corn Bunting and Little Bustard, either directly or indirectly, through the effects of grazing pressure on vegetation height. Animal density and vegetation cover had direct positive effects in Galerida spp. and Common Quail, respectively. Zitting Cisticola and Little Bustard also showed a direct response to livestock type. Our study emphasizes the importance of grazing pressure as a driver of negative impacts for bird populations in Mediterranean grasslands. Since the ongoing transition from sheep to cattle-based systems involves increases in stocking rate, and therefore potentially higher grazing pressure, we propose a policy change to cap the maximum allowed grazing pressure. At the landscape scale, a mix of sheep and cattle grazed fields would be beneficial for maintaining bird diversity.


Assuntos
Agricultura/métodos , Aves/classificação , Gado/crescimento & desenvolvimento , Animais , Biodiversidade , Aves/crescimento & desenvolvimento , Bovinos , Conservação dos Recursos Naturais , Pradaria , Herbivoria , Gado/classificação , Região do Mediterrâneo , Modelos Teóricos , Ovinos
4.
Bioscience ; 71(4): 337-349, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33867867

RESUMO

In the current era of Big Data, existing synthesis tools such as formal meta-analyses are critical means to handle the deluge of information. However, there is a need for complementary tools that help to (a) organize evidence, (b) organize theory, and (c) closely connect evidence to theory. We present the hierarchy-of-hypotheses (HoH) approach to address these issues. In an HoH, hypotheses are conceptually and visually structured in a hierarchically nested way where the lower branches can be directly connected to empirical results. Used for organizing evidence, this tool allows researchers to conceptually connect empirical results derived through diverse approaches and to reveal under which circumstances hypotheses are applicable. Used for organizing theory, it allows researchers to uncover mechanistic components of hypotheses and previously neglected conceptual connections. In the present article, we offer guidance on how to build an HoH, provide examples from population and evolutionary biology and propose terminological clarifications.

5.
Materials (Basel) ; 14(4)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672140

RESUMO

We report on the pilot scale synthesis and melt spinning of poly(ethylene furanoate) (PEF), a promising bio-based fiber polymer that can heave mechanical properties in the range of commercial poly(ethylene terephthalate) (PET) fibers. Catalyst optimization and solid state polycondensation (SSP) allowed for intrinsic viscosities of PEF of up to 0.85 dL·g-1. Melt-spun multifilament yarns reached a tensile strength of up to 65 cN·tex-1 with an elongation of 6% and a modulus of 1370 cN·tex-1. The crystallization behavior of PEF was investigated by differential scanning calorimetry (DSC) and XRD after each process step, i.e., after polymerization, SSP, melt spinning, drawing, and recycling. After SSP, the previously amorphous polymer showed a crystallinity of 47%, which was in accordance with literature. The corresponding XRD diffractograms showed signals attributable to α-PEF. Additional, clearly assignable signals at 2θ > 30° are discussed. A completely amorphous structure was observed by XRD for as-spun yarns, while a crystalline phase was detected on drawn yarns; however, it was less pronounced than for the granules and independent of the winding speed.

6.
Conserv Lett ; 13(4): e12713, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32999687

RESUMO

Increasing evidence-synthesized in this paper-shows that economic growth contributes to biodiversity loss via greater resource consumption and higher emissions. Nonetheless, a review of international biodiversity and sustainability policies shows that the majority advocate economic growth. Since improvements in resource use efficiency have so far not allowed for absolute global reductions in resource use and pollution, we question the support for economic growth in these policies, where inadequate attention is paid to the question of how growth can be decoupled from biodiversity loss. Drawing on the literature about alternatives to economic growth, we explore this contradiction and suggest ways forward to halt global biodiversity decline. These include policy proposals to move beyond the growth paradigm while enhancing overall prosperity, which can be implemented by combining top-down and bottom-up governance across scales. Finally, we call the attention of researchers and policy makers to two immediate steps: acknowledge the conflict between economic growth and biodiversity conservation in future policies; and explore socioeconomic trajectories beyond economic growth in the next generation of biodiversity scenarios.

7.
People Nat (Hoboken) ; 2(2): 305-316, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32626843

RESUMO

Making agriculture sustainable is a global challenge. In the European Union (EU), the Common Agricultural Policy (CAP) is failing with respect to biodiversity, climate, soil, land degradation as well as socio-economic challenges.The European Commission's proposal for a CAP post-2020 provides a scope for enhanced sustainability. However, it also allows Member States to choose low-ambition implementation pathways. It therefore remains essential to address citizens' demands for sustainable agriculture and rectify systemic weaknesses in the CAP, using the full breadth of available scientific evidence and knowledge.Concerned about current attempts to dilute the environmental ambition of the future CAP, and the lack of concrete proposals for improving the CAP in the draft of the European Green Deal, we call on the European Parliament, Council and Commission to adopt 10 urgent action points for delivering sustainable food production, biodiversity conservation and climate mitigation.Knowledge is available to help moving towards evidence-based, sustainable European agriculture that can benefit people, nature and their joint futures.The statements made in this article have the broad support of the scientific community, as expressed by above 3,600 signatories to the preprint version of this manuscript. The list can be found here (https://doi.org/10.5281/zenodo.3685632).

9.
Glob Chang Biol ; 25(3): 1032-1048, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30548757

RESUMO

The European Union (EU) has recently published its first list of invasive alien species (IAS) of EU concern to which current legislation must apply. The list comprises species known to pose great threats to biodiversity and needs to be maintained and updated. Horizon scanning is seen as critical to identify the most threatening potential IAS that do not yet occur in Europe to be subsequently risk assessed for future listing. Accordingly, we present a systematic consensus horizon scanning procedure to derive a ranked list of potential IAS likely to arrive, establish, spread and have an impact on biodiversity in the region over the next decade. The approach is unique in the continental scale examined, the breadth of taxonomic groups and environments considered, and the methods and data sources used. International experts were brought together to address five broad thematic groups of potential IAS. For each thematic group the experts first independently assembled lists of potential IAS not yet established in the EU but potentially threatening biodiversity if introduced. Experts were asked to score the species within their thematic group for their separate likelihoods of i) arrival, ii) establishment, iii) spread, and iv) magnitude of the potential negative impact on biodiversity within the EU. Experts then convened for a 2-day workshop applying consensus methods to compile a ranked list of potential IAS. From an initial working list of 329 species, a list of 66 species not yet established in the EU that were considered to be very high (8 species), high (40 species) or medium (18 species) risk species was derived. Here, we present these species highlighting the potential negative impacts and the most likely biogeographic regions to be affected by these potential IAS.


Assuntos
Biodiversidade , Ecossistema , Espécies Introduzidas/tendências , Animais , Conferências de Consenso como Assunto , Política Ambiental , União Europeia , Espécies Introduzidas/estatística & dados numéricos , Medição de Risco
10.
Artigo em Inglês | MEDLINE | ID: mdl-30424500

RESUMO

No saturation in the introduction, acceleration of spread and the increasing impacts of alien species are a characteristic feature of the Anthropocene. Concomitantly, alien species affecting human health are supposed to increase, mainly due to increasing global trade and climate change. In this study, we assess challenges and solutions posed by such species to the public health sector in Austria over the next few decades. We did so using an online questionnaire circulated to 131 experts and stakeholders working on human health and biological invasions, supplemented by in-depth interviews with eleven selected experts. Results from the online survey and in-depth interviews largely support and complement each other. Experts and stakeholders suggest that (i) the allergenic Ambrosia artemisiifolia (common ragweed), the photodermatoxic Heracleum mantegazzianum (giant hogweed), and vectors of diseases such as Aedes albopictus (Asian tiger mosquito) are considered the alien species posing the most severe challenges; (ii) challenges are expected to increase in the next few decades and awareness in the public health sector is not sufficient; (iii) effective and efficient solutions are mainly related to prevention. Specific solutions include pathway management of introduction and spread by monitoring and controlling established populations of ragweed, hogweed and mosquitos.


Assuntos
Mudança Climática , Gerenciamento Clínico , Política de Saúde/legislação & jurisprudência , Espécies Introduzidas/legislação & jurisprudência , Saúde Pública/legislação & jurisprudência , Áustria , Humanos , Inquéritos e Questionários
11.
Proc Natl Acad Sci U S A ; 115(10): E2264-E2273, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29432147

RESUMO

Our ability to predict the identity of future invasive alien species is largely based upon knowledge of prior invasion history. Emerging alien species-those never encountered as aliens before-therefore pose a significant challenge to biosecurity interventions worldwide. Understanding their temporal trends, origins, and the drivers of their spread is pivotal to improving prevention and risk assessment tools. Here, we use a database of 45,984 first records of 16,019 established alien species to investigate the temporal dynamics of occurrences of emerging alien species worldwide. Even after many centuries of invasions the rate of emergence of new alien species is still high: One-quarter of first records during 2000-2005 were of species that had not been previously recorded anywhere as alien, though with large variation across taxa. Model results show that the high proportion of emerging alien species cannot be solely explained by increases in well-known drivers such as the amount of imported commodities from historically important source regions. Instead, these dynamics reflect the incorporation of new regions into the pool of potential alien species, likely as a consequence of expanding trade networks and environmental change. This process compensates for the depletion of the historically important source species pool through successive invasions. We estimate that 1-16% of all species on Earth, depending on the taxonomic group, qualify as potential alien species. These results suggest that there remains a high proportion of emerging alien species we have yet to encounter, with future impacts that are difficult to predict.


Assuntos
Espécies Introduzidas/estatística & dados numéricos , Animais , Biodiversidade , Ecossistema , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Espécies Introduzidas/história , Modelos Biológicos , Dinâmica Populacional/história
12.
ACS Omega ; 3(9): 11290-11299, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459238

RESUMO

Here, we provide a deeper insight into the state of sulfur confined in ultramicroporous carbon (UMC) and clarify its electrochemical reaction mechanism with lithium by corroborating the results obtained using various experimental techniques, such as X-ray photoelectron spectroscopy, electron energy loss spectroscopy, in situ Raman spectroscopy, and in situ electrochemical impedance spectroscopy. In combination, these results indicate that sulfur in UMC exists as linear polymeric sulfur rather than smaller allotropes. The electrochemical reactivity of lithium with sulfur confined in UMC (pore size ≤0.7 nm) is different from that of sulfur confined in microporous carbon (≤2 nm, or ultramicroporous carbon containing significant amount of micropores) and mesoporous carbon (>2 nm). The observed quasi-solid-state reaction of lithium with sulfur in UMC with a single voltage plateau during the discharge/charge process is due to the effective separation of solvent molecules from the active material. The size of carbon pores plays a vital role in determining the reaction path of lithium with sulfur confined in UMC.

13.
Ambio ; 46(4): 428-442, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28150137

RESUMO

Interdisciplinarity is needed to gain knowledge of the ecology of invasive species and invaded ecosystems, and of the human dimensions of biological invasions. We combine a quantitative literature review with a qualitative historical narrative to document the progress of interdisciplinarity in invasion science since 1950. Our review shows that 92.4% of interdisciplinary publications (out of 9192) focus on ecological questions, 4.4% on social ones, and 3.2% on social-ecological ones. The emergence of invasion science out of ecology might explain why interdisciplinarity has remained mostly within the natural sciences. Nevertheless, invasion science is attracting social-ecological collaborations to understand ecological challenges, and to develop novel approaches to address new ideas, concepts, and invasion-related questions between scholars and stakeholders. We discuss ways to reframe invasion science as a field centred on interlinked social-ecological dynamics to bring science, governance and society together in a common effort to deal with invasions.


Assuntos
Ecologia , Comunicação Interdisciplinar , Espécies Introduzidas
14.
Nat Commun ; 8: 14435, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198420

RESUMO

Although research on human-mediated exchanges of species has substantially intensified during the last centuries, we know surprisingly little about temporal dynamics of alien species accumulations across regions and taxa. Using a novel database of 45,813 first records of 16,926 established alien species, we show that the annual rate of first records worldwide has increased during the last 200 years, with 37% of all first records reported most recently (1970-2014). Inter-continental and inter-taxonomic variation can be largely attributed to the diaspora of European settlers in the nineteenth century and to the acceleration in trade in the twentieth century. For all taxonomic groups, the increase in numbers of alien species does not show any sign of saturation and most taxa even show increases in the rate of first records over time. This highlights that past efforts to mitigate invasions have not been effective enough to keep up with increasing globalization.


Assuntos
Espécies Introduzidas , Simulação por Computador , Geografia , Internacionalidade , Ilhas , Especificidade da Espécie , Fatores de Tempo
15.
Science ; 346(6206): 241-4, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25278504

RESUMO

In 2010, the international community, under the auspices of the Convention on Biological Diversity, agreed on 20 biodiversity-related "Aichi Targets" to be achieved within a decade. We provide a comprehensive mid-term assessment of progress toward these global targets using 55 indicator data sets. We projected indicator trends to 2020 using an adaptive statistical framework that incorporated the specific properties of individual time series. On current trajectories, results suggest that despite accelerating policy and management responses to the biodiversity crisis, the impacts of these efforts are unlikely to be reflected in improved trends in the state of biodiversity by 2020. We highlight areas of societal endeavor requiring additional efforts to achieve the Aichi Targets, and provide a baseline against which to assess future progress.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Extinção Biológica
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