DCEA - Artigos em Revistas Internacionais / Articles in International Journals
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Browsing DCEA - Artigos em Revistas Internacionais / Articles in International Journals by Author "Ah-Peng, Claudine"
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- Challenges, advances and perspectives in Island BiogeographyPublication . Borges, Paulo A. V.; Cardoso, Pedro; Gabriel, Rosalina; Ah-Peng, Claudine; Emerson, Brent C.Island biogeographical research is becoming more and more fashionable, with the continuous identification of new challenges that are critical for the advancement of science. In this contribution we identify biases and limitations associated with island biogeographical studies, and also describe recent advances and propose new perspectives. The main proposals include: 1) downscaling island biogeographical studies to local/plot scale; 2) investigating geographical patterns of intra-specific genetic variation to infer dispersal processes among and within islands; 3) using applied biogeographical research to respond to the current island biodiversity crisis; and 4) applying new computer-intensive methods such as artificial intelligence (AI) approaches.
- Characterizing and quantifying water content in 14 species of bryophytes present in azorean native vegetationPublication . Coelho, Márcia Catarina Mendes; Gabriel, Rosalina; Ah-Peng, ClaudineBryophytes are an important component of plant diversity, may be found from sea level to mountaintops, and are particularly conspicuous on the Azores islands. These plants rely on environmental water, which acquires intercepting rain and dew (liquid water) and uses fog (water vapor), and transports both externally, by capillary forces, and internally, in different cells (specialized or not). This study characterizes and quantifies the ability of six liverworts and eight mosses to retain water, through different pathways, and to lose water by evaporation. Twelve replicates of each species were collected in Azorean native vegetation during the summer of 2016. The absolute water content (AWC) was obtained through measurements of specimens saturated, without free water, and completely dry. Most of the 14-target species showed an ectohydric behavior pattern retaining more than 60% of water through gametophyte surface. The AWC value ranged from 646% in Polytrichum commune to 5584% in Sphagnum subnitens. The water loss by direct evaporation showed, for most of species, an exponential decay curve along time. Understanding how much native bryophytes, acquire, store, and release water into the system contributes not only to the knowledge of native vegetation resilience but also to potential impacts on the availability and quality of water—a major ecosystem service performed by bryophytes.
- Functional diversity and composition of bryophyte water-related traits in Azorean native vegetationPublication . Henriques, Débora; Rigal, François; Borges, Paulo A. V.; Ah-Peng, Claudine; Gabriel, RosalinaBACKGROUND: Functional trait-based approaches link species diversity patterns to ecosystem functioning. In the context of global change, understanding these links is vital for developing holistic biodiversity management strategies. Bryophytes, important ecosystem components owing to their biogeochemical functions, have not been the focus of many functional studies. AIMS: This is the first assessment of bryophyte functional diversity in the Azores archipelago, aiming to uncover multivariate trait richness and composition patterns along the elevational gradient on Terceira Island. METHODS: Based on five water acquisition and retention traits of leafy liverworts and mosses, we calculated functional diversity metrics within and among six bryophyte communities sampled along a 1021-m elevational transect. RESULTS: Trait composition differed significantly between coastal and mountain communities. Mosses presented inrolled leaves and ornamented leaf cells at low elevation but not at high elevation. These patterns were associated with an uphill shift from drier and warmer conditions to a moister and cooler environment. CONCLUSIONS: Future climatic changes might affect bryophyte functional diversity patterns in Terceira Island, particularly for mosses. These results can be directly compared with those obtained for other archipelagos where the same protocol has been applied, allowing a joint assessment of insular vegetation functional diversity patterns.
- Mosses and liverworts show contrasting elevational distribution patterns in an oceanic island (Terceira, Azores) : the influence of climate and spacePublication . Henriques, Débora; Borges, Paulo A. V.; Ah-Peng, Claudine; Gabriel, RosalinaDue to ongoing global changes, it is essential to establish a baseline record from which to determine future shifts in species distributions and community assembly patterns. In this context, we used digitised historical bryophyte distribution data along a 1021 m elevational gradient in Terceira Island (Azores) to determine how bryophyte species distribution varies with elevation and which spatial and climatic drivers contribute to this variation. We used ordinary least squares analysis to test for climatic and spatial data as explanatory variables for bryophyte richness and Mid-Domain Null simulations to assess the influence of spatial constraints on species distributions. Bryophyte richness follows a hump-shaped pattern, with mosses predominating in the first half of the gradient and liverworts in the second half. While moss richness did not correlate to any climatic variables and responded weakly to the presence of forest cover, liverwort presence was related to temperature, rainfall, humidity and the occurrence of native forest areas, suggesting that these plants are more sensitive to changes in their environment and can thus be used as better indicator species for climate change. Despite their inherent biases, our study shows that historically compiled data can be a valuable tool for preliminary assessment of macroecological patterns.
- A roadmap for island biology : 50 fundamental questions after 50 years of The Theory of Island BiogeographyPublication . Patiño, Jairo; Whittaker, Robert J.; Borges, Paulo A. V.; Fernández-Palacios, José María; Ah-Peng, Claudine; Araújo, Miguel B.; Ávila, Sérgio P.; Cardoso, Pedro; Cornuault, Josselin; Boer, Erik J.; Nascimento, Lea; Gil, Artur José Freire; González-Castro, Aarón; Gruner, Daniel S.; Heleno, Ruben; Hortal, Joaquín; Illera, Juan Carlos; Kaiser-Bunbury, Christopher N.; Matthews, Thomas J.; Papadopoulou, Anna; Pettorelli, Nathalie; Price, Jonathan; Santos, Ana C.; Steinbauer, Manuel J.; Triantis, Kostas A.; Valente, Luis; Vargas, Pablo; Weigelt, Patrick; Emerson, Brent C.AIMS The 50th anniversary of the publication of the seminal book, The Theory of Island Biogeography, by Robert H. MacArthur and Edward O. Wilson, is a timely moment to review and identify key research foci that could advance island biology. Here, we take a collaborative horizon-scanning approach to identify 50 fundamental questions for the continued development of the field. LOCATION: Worldwide. METHODS: We adapted a well-established methodology of horizon scanning to identify priority research questions in island biology, and initiated it during the Island Biology 2016 conference held in the Azores. A multidisciplinary working group prepared an initial pool of 187 questions. A series of online surveys was then used to refine a list of the 50 top priority questions. The final shortlist was restricted to questions with a broad conceptual scope, and which should be answerable through achievable research approaches. RESULTS: Questions were structured around four broad and partially overlapping island topics, including: (Macro)Ecology and Biogeography, (Macro)Evolution, Community Ecology, and Conservation and Management. These topics were then subdivided according to the following subject areas: global diversity patterns (five questions in total); island ontogeny and past climate change (4); island rules and syndromes (3); island biogeography theory (4); immigration–speciation–extinction dynamics (5); speciation and diversification (4); dispersal and colonization (3); community assembly (6); biotic interactions (2); global change (5); conservation and management policies (5); and invasive alien species (4). MAIN CONCLUSIONS: Collectively, this cross-disciplinary set of topics covering the 50 fundamental questions has the potential to stimulate and guide future research in island biology. By covering fields ranging from biogeography, community ecology and evolution to global change, this horizon scan may help to foster the formation of interdisciplinary research networks, enhancing joint efforts to better understand the past, present and future of island biotas.
- Scaling a- and b-diversity : bryophytes along an elevational gradient on a subtropical oceanic Island (La Palma, Canary Islands)Publication . Hernández-Hernández, Raquel; Borges, Paulo A. V.; Gabriel, Rosalina; Rigal, François; Ah-Peng, Claudine; González-Mancebo, Juana M.QUESTIONS: We addressed three questions: (1) what is the variation of a- and b-diversity of bryophyte communities across spatial scales in an elevational gradient; (2) is spatial variation characteristic of different phylogenetic (mosses/ liverworts) and/or ecological groups (terrestrials/epiphytes); and (3) what is the CONTRIBUTION of species richness and species replacement (true turnover) to b-diversity along the elevational gradient? LOCATION: La Palma, Canary Islands, Spain. METHODS: An elevational transect spanning 0–2200 m a.s.l was sampled at altitudinal intervals of ca. 200 m, two 10 m 9 10 m plots were established at each elevation and inside each plot three 2 m 9 2 m quadrats were randomly selected. Within each quadrat, bryophytes were sampled in three replicate microplots of 10 cm 9 5 cm, for each substrate: soil, rocks, leaves, humus, decaying wood and tree trunks at three heights. We evaluated a- and b-diversity at plot and elevational level for all bryophytes and for phylogenetic and ecological Groups. Values of b-diversity were further decomposed into replacement and richness differences. We tested the relationship between a- and b-diversity and elevation using linear models with and without a quadratic term (elevation2) in an AICc-based framework. RESULTS: A total of 121 species were recorded along the transect. Alpha-diversity showed a hump-shaped pattern with elevation for all bryophytes, liverworts and epiphytic species, however, terrestrial species and mosses displayed no clear pattern. Species replacement was the main driver of b-diversity for all bryophytes and also for mosses and terrestrial species, and at different scales (elevational belt and quadrat). The contribution of species replacement increased with elevation, except for epiphytes and terrestrials. CONCLUSIONS: Our study contributes towards an understanding of the spatial organization of bryophyte diversity at different scales along an insular elevational gradient. We showed that bryophyte diversity was mostly influenced by species replacement at the largest scale. The observed differences in b-diversity decomposition between bryophyte phylogenetic and ecological groups could be dependent on climatic conditions and substrate availability. The strong differences observed along the elevational gradient related to true turnover are especially important in the current global change scenario.
- Topography-driven isolation, speciation and a global increase of endemism with elevationPublication . Steinbauer, Manuel J.; Field, Richard; Grytnes, John-Arvid; Trigas, Panayiotis; Ah-Peng, Claudine; Attorre, Fabio; Birks, H. John B.; Borges, Paulo A. V.; Cardoso, Pedro; Chou, Chang-Hung; De Sanctis, Michele; Sequeira, Miguel M.; Duarte, Maria C.; Elias, Rui B.; Fernández-Palacios, José María; Gabriel, Rosalina; Gereau, Roy E.; Gillespie, Rosemary G.; Greimler, Josef; Harter, David E. V.; Huang, Tsurng-Juhn; Irl, Severin D. H.; Jeanmonod, Daniel; Jentsch, Anke; Jump, Alistair S.; Kueffer, Christoph; Nogué, Sandra; Otto, Rüdiger; Price, Jonathan; Romeiras, Maria M.; Strasberg, Dominique; Stuessy, Tod; Svenning, Jens-Christian; Vetaas, Ole R.; Beierkuhnlein, CarlAIM: Higher-elevation areas on islands and continental mountains tend to be separated by longer distances, predicting higher endemism at higher elevations; our study is the first to test the generality of the predicted pattern. We also compare it empirically with contrasting expectations from hypotheses invoking higher speciation with area, temperature and species richness. Location Thirty-two insular and 18 continental elevational gradients from around the world. Methods We compiled entire floras with elevation-specific occurrence information, and calculated the proportion of native species that are endemic (‘percent endemism’) in 100-m bands, for each of the 50 elevational gradients. Using generalized linear models, we tested the relationships between percent endemism and elevation, isolation, temperature, area and species richness. RESULTS: Percent endemism consistently increased monotonically with elevation, globally. This was independent of richness–elevation relationships, which had varying shapes but decreased with elevation at high elevations. The endemism–elevation relationships were consistent with isolation-related predictions, but inconsistent with hypotheses related to area, richness and temperature. Main conclusions Higher per-species speciation rates caused by increasing isolation with elevation are the most plausible and parsimonious explanation for the globally consistent pattern of higher endemism at higher elevations that we identify. We suggest that topography-driven isolation increases speciation rates in mountainous areas, across all elevations and increasingly towards the equator. If so, it represents a mechanism that may contribute to generating latitudinal diversity gradients in a way that is consistent with both present-day and palaeontological evidence.