Browsing by Issue Date, starting with "2008"
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- Using predictive models of species distribution to validate biodiversity data: case studies for Madeira IslandPublication . Jiménez-Valverde, Alberto; Hortal, Joaquín; Lobo, Jorge M.; Borges, Paulo A. V.; Abreu, Cristina; Aguiar, António F.; Azevedo, Eduardo B.; Boieiro, Mário; Fontinha, Susana; Jardim, Roberto; Oliveira, Paulo; Sérgio, Cecília; Serrano, Artur R. M.; Sim-Sim, Manuela; Nunes, DuarteOs modelos preditivos de distribuição de espécies são uma importante ferramenta para lidar com a falta de informação biogeográfica existente para a maior parte dos taxa. Com esta técnica, estabelece -se uma relação entre a variável dependente (presença/ausência de uma espécie) e um conjunto de variáveis potencialmente preditoras, e é criado um mapa com a probabilidade de presença da espécie para uma determinada área de interesse. Neste capítulo, é usado o programa Maxent para criar modelos de distribuição potencial de um conjunto seleccionado de espécies, e os resultados obtidos são discutidos com base no conhecimento de especialistas nessas espécies.
- Use of ATLANTIS TIERRA 2.0 in mapping the biodiversity (invertebrates and bryophytes) of caves in the Azorean archipelagoPublication . Borges, Paulo A. V.; Gabriel, Rosalina; Pereira, Fernando E. A. P.; Pereira, Enésima; Sousa, EvaIn this contribution the software ATLANTIS Tierra 2.0 is described as a promising tool to be used in the conservation management of the animal and plant biodiversity of caves in Macaronesia. In the Azores, the importance of cave entrances to bryophytes is twofold: i) since these are particularly humid, sheltered habitats, they support a diverse assemblage of bryophyte species and circa 25% of the Azorean brioflora is referred to this habitat and ii) species, either endemic or referred in the European red list due to their vulnerability (19 species) or rarity (13) find refuge there. Cave adapted arthropods are also diverse in the Azores and 21 endemic obligate cave species were recorded. Generally these species have restricted distributions and some are known from only one cave. ATLANTIS Tierra 2.0 allows the mapping of the distribution of all species in a 500 x 500 m grid in a GIS interface. This allows an easy detection of species rich caves (hotspots) and facilitates the interpretation of spatial patterns of species distribution. For instance, predictive models of species distribution could be constructed using the distribution of lava flows or other environmental variables. Using this new tool we will be better equipped to answer the following questions: a) Where are the current “hotspot caves” of biodiversity in the Azores?; b) How many new caves need to be selected as specially protected areas in order to conserve the rarest endemic taxa?; c) Is there congruence between the patterns of richness and distribution of invertebrates and bryophytes?; d) Are environmental variables good surrogates of species distributions?
- Um arquipélago de geometria variável: representações dos Açores no período moderno (séculos XVI-XVIII)*Publication . Rodrigues, José DamiãoNo presente artigo, tendo como objecto de estudo as ilhas dos Açores no período moderno (séculos XVI-XVIII), procuramos demonstrar, a partir da análise de fontes açorianas e estrangeiras (crónicas, histórias, descrições, relatórios) que não existia uma representação espacial única do arquipélago tal como o conhecemos. As identidades territoriais e as representações espaciais correspondentes são indissociáveis de um determinado percurso histórico e das relações e actividades que se desenvolvem no quadro de um espaço concreto. Nos Açores modernos, diversos factores, entre os quais a descontinuidade geográfica e o “poder do lugar”, contribuíram para impedir a construção de uma concepção de região à escala do arquipélago.
- Distribution and abundance of arthropod species in pasture communities of three Azorean islands (Santa Maria, Terceira and Pico)Publication . Borges, Paulo A. V.This work provides evidence that the "hollow curve" is a consistent pattern in the range size distribution of taxonomic and ecological groups of arthropod pasture dwelling species. Many of the inconsistent results relating range size to herbivores diet breadth are probably due to historical constraints in the colonization of the islands and particular characteristics of the habitats studied (e.g. types of resources available). The positive relationship between range size and abundance may be explained by the "resource usage model". However, the slope of the regression line relating distribution to abundance was similar for different groups which suggests there is no difference in the way that the species’ local abundance scales with distribution in the four assemblages of species studied and that there is a close relationship between the trophic groups studied. This suggests that the “resource availability model” could be the explanation for the distribution and abundance of pasture spider and insect species. More work needs to be conducted in order to evaluate the relationship between diet breadth, habitat specialization and range size in the islands.
- Santa Maria - Zona SubmersaPublication . Neto, Ana I.; Wallenstein, Francisco; Álvaro, Nuno V.; Raposeiro, Pedro M.; Azevedo, José M. N.À semelhança das restantes ilhas do arquipélago dos Açores, em Santa Maria, predomina o substrato rochoso. Os fundos rochosos até aos 30 m de profundidade apresentam morfologias variadas, alternando entre calhau rolado, blocos e escoada lávica compacta, predominando esta última. Há apenas duas baías onde ocorre acumulação de substrato arenoso (Praia Formosa na costa Sul e São Lourenço na costa Leste), com afloramentos pontuais de escoada lávica. Este tipo de fundo ocorre em vários outros locais à volta da ilha, a profundidades que variam entre os 20 e os 30 m, e.g. Baía de Salto dos Cães e junto do Ilhéu das Lagoinhas (costa Norte), Baía do Aveiro e Baía da Maia (costa Leste).
- Improvising at work: the differences between experts and novicesPublication . Batista, Maria da Graça Câmara; Cunha, Miguel Pina eImprovisation is being presented as a relevant process in organizational environments marked by speed and unpredictability, but it is still an under-investigated topic. The theoretical question for which we seek to provide a preliminary insight is: How does novice behavior differ from expert behavior with regard to the use of improvisational action? We build on the integration of several disciplines to advance a theoretical model. We predict that several constructs will have differential effects on lhe adoption of improvisation by experts and novices. The paper contributes to the literature by suggesting that unexpected events with be approached differently by peopte with different levels or expertise, something which in turn will have both theoretical and applied implications.
- Applied Aspects of Marine Parasitology : Proceedings of the International Workshop on Marine ParasitologyPublication . Afonso-Dias, Isabel, ed.; Menezes, Gui M., ed.; Mackenzie, Ken, ed.; Eiras, Jorge C., ed.Marine parasites are of immense ecological and economic importance. Almost all (if not all) groups of marine animals including the various invertebrates and, among the vertebrates, fish, marine birds and reptiles, are hosts to parasites, often with high prevalence’s and intensities of infection. Total global (marine and freshwater) aquaculture in 2004 was estimated to be worth more than US$ 55 billion. The commercial value of cultured salmonid fishes alone in 2001 was around US$ 3.84 billion (7.44 billion for all finfish). Disease, and much of it due to parasites, is the single most important factor threatening the aquaculture industry. Parasites led to the collapse of European flat oyster aquaculture in the years following 1979 and to devastating effects on oyster culture on the North American east coast over many years. Mass mortalities caused by parasites in the wild have not been well documented for marine vertebrates and invertebrates, due to the large spaces in the oceans involved and the difficulties in monitoring such effects, but there can be no doubt that parasites are responsible for mass mortalities of natural fish populations, and there is evidence for the involvement of parasites in beaching’s of whales. Introduction of a monogenean ectoparasite into the Aral Sea led to the total collapse of sturgeon and caviar fisheries there in the thirties. Economic losses may be via effects on the human psyche: reports on herring worms on German television some years ago induced many people to change their dietary habits away from fish, causing considerable losses to fishermen. Fish are routinely screened for parasite infections (many of them only of aesthetic significance), which causes considerable costs. However, the useful role of parasites must not be forgotten. They can be used in the study of host populations and migrations, and in pollution monitoring, because pollution affects the composition of parasite communities, and because some parasites store certain pollutants to a higher degree than their hosts. For all these reasons, a workshop dealing with applied aspects of marine parasites is important. At such a workshop, experts from around the world can meet, exchange ideas and communicate recent findings to younger participants, that is, to the future of the discipline. The list of speakers and participants shows that both these objectives have been achieved at this workshop, which concentrated on fish parasites. Speakers included outstanding experts from Portugal, Canada, the United States, Germany, Britain, Norway, and Chile. Particularly welcome: the conference photo shows many young faces. Seminars at the symposium ranged from disease trends in natural marine communities, the use of parasites in fish population studies, deep-sea parasites, parasites as indicators of environmental change, to parasites in mariculture, to mention only some. Of particular interest also: several seminars dealt with parasites in Azores and other Portuguese waters, and included a visit to the local fish market. There can be no doubt that a seminar on how to prepare whole mounts of parasites was welcomed especially by the younger participants. The Proceedings of this workshop will be useful not only to people involved in local fisheries and parasite work, but also to the international community of parasitologists and to people associated with the fishing industry.
- Effects of fish removal in the Furnas Lake, AzoresPublication . Bio, Ana; Couto, A.; Costa, R.; Prestes, Afonso L.; Vieira, N.; Valente, A.; Azevedo, José M. N.The Furnas Lake is a small volcanic, monomitic and increasingly eutrophised water body. Next to agricultural nutrient inputs, high densities of herbivorous fish are thought to contribute to high levels of turbidity in the lake, through zooplankton consumption and re-suspension of the nutrients accumulated in the sediment. According to the alternative state hypothesis a shift from turbid to clear water conditions is favoured by reduction of nutrient concentrations, increased light availability and reduction of planktivorous and benthos-feeding fish stock. To improve water quality in the Furnas Lake, a substantial part of the bottom-feeding fish population (62% of the estimated common carp population, Cyprinus carpio, and 5% of the estimated roach population, Rutilus rutilus) was removed. Effects of fish removal on turbidity and associated trophic state were analysed next to postmanipulation chlorophyll a concentration, zooplankton and macrophytes densities. Results suggest that fish removal was not enough to change lake conditions towards a lasting clear state dominated by macrophytes. Excessive nutrient load, in water and sediments, nutrient input from the lake basin and fish recruitment causing enhanced zooplankton grazing are appointed causes. Any further biomanipulation efforts should be associated to nutrient reduction; and continued monitoring of water quality, fish stock, macrophytes and zooplankton is needed.
- Science, society, politics, and the media: joining efforts to manage the risk of termite infestation in the AzoresPublication . Arroz, Ana Margarida Moura; Palos, Ana Cristina Pires; Rego, Isabel Estrela; Borges, Paulo A. V.Termites are well-established and serious pests of structural wood infestation in different parts of the world. Presently, in the Azores archipelago (Portugal), the drywood termite Cryptotermes brevis (Insecta, Isoptera) has been referred to four of the nine islands, and the damages to the buildings and other artefacts are severe and constitute a serious threat, especially in its main towns. In order to control the situation there has been a considerable scientific and political investment to survey and classify the infestation, and to develop mitigation strategies, over the last five years. Nevertheless, the infestation is far from being controlled and, also, most of the Azorean citizens are still unaware of the dangers and risks associated to this urban pest. If, however, effective educational and management practices are initiated soon, the losses from C. brevis can be greatly reduced. Therefore, the major aims of this research project are: (i) to understand people’s perspectives about the consequences of the termite infestation and their appraisal about the effectiveness of the proposed and existing management strategies; (ii) to understand the functions of the media in the making of public opinion; (iii) to develop simple ways of communicating complex technical information according to people’s perception of who is accountable and trustworthy, in order to avoid misunderstandings between science, politics, managers and society; (iv) to develop and implement devices focused on the communication between the population and the main stakeholders, to promote the involvement of citizens and their commitment as essential partners of the termite control. This paper aims to integrate data from the abovementioned stakeholders in order to identify communication problems, to create adequate strategies to solve conflicts, to facilitate dialogue and partnerships among stakeholders and to promote termite risk literacy. Data was gathered using several techniques, including interviews, descriptive-interpretative analysis of media, scientific discourses and existing operational programs. Data shows that the lack of integration among stakeholders is the most obvious barrier to be overcome by the communication devices to implement.
- A Lista Top 100Publication . Martín, José L.; Borges, Paulo A. V.; Arechavaleta, Manuel; Faria, Bernardo F."Evitar a extinção das espécies é um dos maiores desafios actuais da ciência da conservação. A magnitude da perda de espécies é hoje tão importante que alguns autores defendem que estamos a ser testemunhas da sexta grande extinção na história da vida (Leakey & Lewin, 1995). De facto, no nosso planeta desta vez é a acção devastadora do Homem a força motriz que está a alterar habitats, a colocar em risco ecossistemas, e a extinguir inúmeras espécies, muitas delas desconhecidas para a ciência (Lawton & May, 1995; Pimm et al., 1995, 1996; Chapin et al., 2000). Durante os últimos séculos estas extinções tem sido muito significativas nas ilhas de todo o mundo (Reid & Miller, 1989; Lawton & May, 1995; Sadler, 1999; Steadman & Martin, 2003), o que tem estimulado o debate sobre a questão se os endemismos insulares são intrinsecamente mais sensíveis às ameaças do que as formas continentais (Manne et al., 1999; Sax et al., 2002; Frankham, 2005). Contudo embora não pareça claro que assim seja (Manne & Pimm, 2001; Biber, 2002), o facto é que as ilhas por serem territórios com muitos taxa endémicos de distribuição reduzida a espaços limitados e, como consequência disso, com poucas possibilidades de escapar a uma eventual ameaça –como por exemplo a introdução de um novo predador–, tem o risco de extinção aumentado (Duncan & Blackburn, 2007). Evidências mostram igualmente que nas ilhas o número de espécies de plantas vasculares não nativas tem subido mais do que a extinção do número de espécies nativas mas que nas aves as extinções igualam o ganho de espécies exóticas (Sax et al., 2002). O facto é que, independentemente da maior ou menor propensão ao desaparecimento das espécies insulares, as consequências devastadoras das ameaças externas nos territórios isolados levam a que as extinções nas ilhas sejam mais frequentes do que nos espaços abertos continentais (Quammen, 1997). [...]"