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1.
Nat Commun ; 11(1): 5601, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154374

RESUMO

The extent to which species can balance out the loss of suitable habitats due to climate warming by shifting their ranges is an area of controversy. Here, we assess whether highly efficient wind-dispersed organisms like bryophytes can keep-up with projected shifts in their areas of suitable climate. Using a hybrid statistical-mechanistic approach accounting for spatial and temporal variations in both climatic and wind conditions, we simulate future migrations across Europe for 40 bryophyte species until 2050. The median ratios between predicted range loss vs expansion by 2050 across species and climate change scenarios range from 1.6 to 3.3 when only shifts in climatic suitability were considered, but increase to 34.7-96.8 when species dispersal abilities are added to our models. This highlights the importance of accounting for dispersal restrictions when projecting future distribution ranges and suggests that even highly dispersive organisms like bryophytes are not equipped to fully track the rates of ongoing climate change in the course of the next decades.


Assuntos
Briófitas/fisiologia , Mudança Climática , Dispersão Vegetal/fisiologia , Briófitas/classificação , Briófitas/crescimento & desenvolvimento , Ecossistema , Europa (Continente) , Extinção Biológica , Previsões , Modelos Teóricos , Vento
2.
J Environ Manage ; 131: 185-95, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24161807

RESUMO

Species distribution models (SDMs) studies suggest that, without control measures, the distribution of many alien invasive plant species (AIS) will increase under climate and land-use changes. Due to limited resources and large areas colonised by invaders, management and monitoring resources must be prioritised. Choices depend on the conservation value of the invaded areas and can be guided by SDM predictions. Here, we use a hierarchical SDM framework, complemented by connectivity analysis of AIS distributions, to evaluate current and future conflicts between AIS and high conservation value areas. We illustrate the framework with three Australian wattle (Acacia) species and patterns of conservation value in Northern Portugal. Results show that protected areas will likely suffer higher pressure from all three Acacia species under future climatic conditions. Due to this higher predicted conflict in protected areas, management might be prioritised for Acacia dealbata and Acacia melanoxylon. Connectivity of AIS suitable areas inside protected areas is currently lower than across the full study area, but this would change under future environmental conditions. Coupled SDM and connectivity analysis can support resource prioritisation for anticipation and monitoring of AIS impacts. However, further tests of this framework over a wide range of regions and organisms are still required before wide application.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Plantas
3.
Ecol Lett ; 10(8): 701-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17594425

RESUMO

Niche-based models calibrated in the native range by relating species observations to climatic variables are commonly used to predict the potential spatial extent of species' invasion. This climate matching approach relies on the assumption that invasive species conserve their climatic niche in the invaded ranges. We test this assumption by analysing the climatic niche spaces of Spotted Knapweed in western North America and Europe. We show with robust cross-continental data that a shift of the observed climatic niche occurred between native and non-native ranges, providing the first empirical evidence that an invasive species can occupy climatically distinct niche spaces following its introduction into a new area. The models fail to predict the current invaded distribution, but correctly predict areas of introduction. Climate matching is thus a useful approach to identify areas at risk of introduction and establishment of newly or not-yet-introduced neophytes, but may not predict the full extent of invasions.


Assuntos
Centaurea/fisiologia , Clima , Demografia , Ecossistema , Modelos Teóricos , Área Sob a Curva , Europa (Continente) , América do Norte , Dinâmica Populacional , Especificidade da Espécie
4.
Microb Ecol ; 45(3): 282-90, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12658523

RESUMO

The aim of this study was to determine the diversity of cultivable bacteria able to degrade feathers and present in soil under temperate climate. We obtained 33 isolates from soil samples, which clustered in 13 ARDRA groups. These isolates were able to grow on solid medium with pigeon feathers as sole carbon and nitrogen source. One representative isolate of each ARDRA group was selected for identification and feather degradation tests. The phylogenetic analysis of 16S rDNA gene fragments revealed that only 4 isolates were gram positives. Two other isolates belonged to the Cytophaga-Flavobacterium group, and the remaining to Proteobacteria. High keratinolysis activity was found for strains related to Bacillus, Cytophagales, Actinomycetales, and Proteobacteria. The 13 selected strains showed variable efficiency in degrading whole feathers and 5 strains were able to degrade maximum 40% to 98% of the whole feathers. After 4 weeks incubation, five strains grown on milled feathers produced more than 0.5 U keratinase per mL. Keratinase activities across the 13 strains were positively correlated with the percentage of feather fragmentation and protein concentration.


Assuntos
Bactérias Aeróbias/metabolismo , Plumas/metabolismo , Microbiologia do Solo , Animais , Bactérias Aeróbias/genética , Bactérias Aeróbias/isolamento & purificação , Sequência de Bases , Columbidae , DNA Bacteriano/química , DNA Bacteriano/genética , Variação Genética , Queratinas/metabolismo , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética
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