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1.
Sci Rep ; 8(1): 2870, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29434266

RESUMO

Plant traits are both responsive to local climate and strong predictors of primary productivity. We hypothesized that future climate change might promote a shift in global plant traits resulting in changes in Gross Primary Productivity (GPP). We characterized the relationship between key plant traits, namely Specific Leaf Area (SLA), height, and seed mass, and local climate and primary productivity. We found that by 2070, tropical and arid ecosystems will be more suitable for plants with relatively lower canopy height, SLA and seed mass, while far northern latitudes will favor woody and taller plants than at present. Using a network of tower eddy covariance CO2 flux measurements and the extrapolated plant trait maps, we estimated the global distribution of annual GPP under current and projected future plant community distribution. We predict that annual GPP in northern biomes (≥45 °N) will increase by 31% (+8.1 ± 0.5 Pg C), but this will be offset by a 17.9% GPP decline in the tropics (-11.8 ± 0.84 Pg C). These findings suggest that regional climate changes will affect plant trait distributions, which may in turn affect global productivity patterns.


Assuntos
Folhas de Planta/fisiologia , Algoritmos , Mudança Climática , Ecossistema , Fenômenos Fisiológicos Vegetais
2.
PLoS One ; 11(1): e0147285, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26799732

RESUMO

Species distribution modeling has been widely used in studying habitat relationships and for conservation purposes. However, neglecting ecological knowledge about species, e.g. their seasonal movements, and ignoring the proper environmental factors that can explain key elements for species survival (shelter, food and water) increase model uncertainty. This study exemplifies how these ecological gaps in species distribution modeling can be addressed by modeling the distribution of the emu (Dromaius novaehollandiae) in Australia. Emus cover a large area during the austral winter. However, their habitat shrinks during the summer months. We show evidence of emu summer habitat shrinkage due to higher fire frequency, and low water and food availability in northern regions. Our findings indicate that emus prefer areas with higher vegetation productivity and low fire recurrence, while their distribution is linked to an optimal intermediate (~0.12 m3 m(-3)) soil moisture range. We propose that the application of three geospatial data products derived from satellite remote sensing, namely fire frequency, ecosystem productivity, and soil water content, provides an effective representation of emu general habitat requirements, and substantially improves species distribution modeling and representation of the species' ecological habitat niche across Australia.


Assuntos
Migração Animal/fisiologia , Dromaiidae/fisiologia , Ecossistema , Incêndios/estatística & dados numéricos , Modelos Teóricos , Solo/classificação , Animais , Austrália , Desastres , Geografia , Tecnologia de Sensoriamento Remoto , Imagens de Satélites , Estações do Ano , Água
3.
PLoS One ; 7(10): e48104, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23110182

RESUMO

One of the available tools for mapping the geographical distribution and potential suitable habitats is species distribution models. These techniques are very helpful for finding poorly known distributions of species in poorly sampled areas, such as the tropics. Maximum Entropy (MaxEnt) is a recently developed modeling method that can be successfully calibrated using a relatively small number of records. In this research, the MaxEnt model was applied to describe the distribution and identify the key factors shaping the potential distribution of the vulnerable Malayan Sun Bear (Helarctos malayanus) in one of the main remaining habitats in Peninsular Malaysia. MaxEnt results showed that even though Malaysian sun bear habitat is tied with tropical evergreen forests, it lives in a marginal threshold of bio-climatic variables. On the other hand, current protected area networks within Peninsular Malaysia do not cover most of the sun bears potential suitable habitats. Assuming that the predicted suitability map covers sun bears actual distribution, future climate change, forest degradation and illegal hunting could potentially severely affect the sun bear's population.


Assuntos
Biodiversidade , Ecologia/métodos , Modelos Biológicos , Ursidae/crescimento & desenvolvimento , Animais , Mudança Climática , Ecologia/tendências , Entropia , Previsões , Geografia , Malásia , Densidade Demográfica , Dinâmica Populacional , Árvores/crescimento & desenvolvimento , Clima Tropical , Ursidae/metabolismo
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