Browsing by Author "Melo, Catarina"
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- Assessing the effects of climate change on arthropod abundance in Azorean pastures: PASTURCLIM project's baseline monitoring dataPublication . Wallon, Sophie; Melo, Catarina; Tsafack, Noelline; Elias, Rui B.; Borges, Paulo A.V.Background The data we present are part of the project PASTURCLIM (Impact of climate change on pasture’s productivity and nutritional composition in the Azores). The project aims to assess the consequences of climate change (e.g. temperature increase) on the grass production and its quality for forage, as well as to assess changes in the arthropod communities associated with the Azorean intensive pastures. An in situ experiment was set up using Open Top Chambers (OTCs), in order to simulate an increasing of temperature (average of +1.2ºC) on pastures. In this contribution, we present the data relative to the arthropod sampling. New information We provide an inventory of all arthropods recorded inside OTCs and in control plots in three intensively managed pastures dominated by grasses in Terceira Island (Azores): two of them dominated by ryegrass, Lolium multiflorum Lam. (Poaceae), located respectively at 186 m and 301 m above sea level; and one field dominated by common velvetgrass, Holcus lanatus L. (Poaceae), located at an altitude of 385 m. A total of 41351 specimens were collected. Organisms collected belong to four classes, 15 orders, 60 families and 171 species/morphospecies (including 34 taxa identified only at order, family or genus level). Therefore, for only 137 taxa, we have a scientific name associated (n = 38918). A total of 75% of the species (n = 129 species) are considered introduced (including all the species with indeterminate colonisation status that are possibly also exotic species (n = 7622)), representing 71% of the total abundance (n = 29664 specimens). A total of 19% of the species (n = 33 species) are considered native non-endemic representing 28% of the total abundance (n = 11608 specimens). Only one endemic species was sampled, the wolf spider Pardosa acorensis Simon, 1883 (1% of the species), representing 0.2% of the total abundance (n = 79 specimens). Spiders (5056 specimens) and beetles (18310 specimens) were the dominant taxa representing, respectively, 20 and 78 morphospecies. Since the main aim of this study was to have a better knowledge on arthropod communities present in Azorean pastures under a simulated temperature increase, the principal novelty of this paper is the contribution with distribution and abundance data to a baseline knowledge on the future consequences of climate changes on arthropod communities in Azorean pastures.
- Canopy insect herbivores in the Azorean Laurisilva forests: key host plant species in a highly generalist insect communityPublication . Ribeiro, Sérvio P.; Borges, Paulo A. V.; Gaspar, Clara; Melo, Catarina; Serrano, Artur R. M.; Amaral, João; Aguiar, Carlos; André, Genage; Quartau, José A.This article explores patterns of insect herbivore distribution in the canopy of the Laurisilva forests on seven islands in the Azores archipelago. To our knowledge, this is one of the first extensive studied of this type in tree or shrub canopies of oceanic island ecosystems. One of the most frequently debated characteristics of such ecosystems is the likely prevalence of vague, ill-defined niches due to taxonomic disharmony, which may have implications for insect-plant interactions. For instance, an increase in ecological opportunities for generalist species is expected due to the lack of predator groups and reduced selection for chemical defence in host plants. The following two questions were addressed: 1) Are specialists rare species, and insect herbivore species randomly distributed among host plant species in the Azores? 2) Are the variances in insect herbivore species composition, frequency and richness explained by host plants or by regional island effects? We expect a proportional distribution of herbivore species between host plants, influenced by host frequency and distinct island effects; otherwise, deviation from expectation might suggest habitat preference for specific host tree crowns. Canopy beating tray samples were performed on seven islands, comprising 50 transects with 1 to 3 plant species each (10 replicates per species), giving 1320 samples from ten host species trees or shrubs in total. From a total of 129 insect herbivore species, a greater number of herbivore species was found on Juniperus brevifolia (s=65) and Erica azorica (s=53). However, the number of herbivore species per individual tree crown was higher for E. azorica than for any other host, on all islands, despite the fact that it was only the fourth more abundant plant. In addition, higher insect species richness and greater insect abundance were found on the trees of Santa Maria Island, the oldest in the archipelago. Insect species composition was strongly influenced by the presence of E. azorica, which was the only host plant with a characteristic fauna across the archipelago, whereas the fauna of other plant crowns was grouped by islands. The great insect occurrence on E. azorica reflects strong habitat fidelity, but only four species were clearly specialists. Our findings indicate a broadly generalist fauna. The simplicity of Azorean Laurisilva contributed to the understanding of insect-plant mechanisms in canopy forest habitats.
- Differential seed dispersal systems of endemic junipers in two oceanic Macaronesian archipelagos: the influence of biogeographic and biological characteristicsPublication . Rumeu, Beatriz; Elias, Rui B.; Padilla, D. P.; Melo, Catarina; Nogales, ManuelThis article evaluates the seed dispersal systems of two congeneric and endemic fleshy-fruited plants in the context of two relatively close oceanic archipelagos. For this purpose, representative populations of the endangered junipers Juniperus cedrus in the Canary Islands and Madeira, and Juniperus brevifolia in the Azores were studied. Despite both species sharing the same biogeographic region, we set out to test whether different conditions of the islands and biological characteristics of each juniper species determine the distinctive guilds of seed dispersers involved. We assessed the quantitative and qualitative role of the potential frugivores, showing that the wintering Turdus torquatus and the native Turdus merula were the main seed dispersers for J. cedrus and J. brevifolia, respectively (Frequency of occurrence: 74.9%, 80.2%; germination increase with respect to controls: 11.6%, 15.5%; for J. cedrus and J. brevifolia, respectively). The endemic lizard Gallotia galloti was quantitatively outstanding as seed disperser of J. cedrus, although its qualitative effect does not appear to be beneficial. The introduced rabbit Oryctolagus cuniculus acts as a disruptor in both natural seed dispersal systems, as inferred from the high percentage of damaged seeds found in their droppings. Our results indicate that J. cedrus and J. brevifolia are primarily adapted to ornithochory processes, T. torquatus and T. merula being their respective legitimate long-distance dispersers. Although these birds should be playing a key role in the connectivity of fragmented populations, the dependence of J. cedrus on a migrant bird involves a notable fragility of the system.
- Diversidade da fauna de insectos fitófagos e de inimigos naturais em culturas frutícolas da ilha Terceira, Açores: a importância do maneio e da heterogeneidade ambientalPublication . Santos, Ana M. C.; Borges, Paulo A. V.; Hortal, Joaquín; Rodrigues, Ana C.; Medeiros, Carlos; Azevedo, Eduardo B.; Melo, Catarina; Lopes, David João Horta"A evidência mostra que os artrópodes constituem uma fracção importante da biodiversidade estrutural e funcional dos habitats terrestres (Kim, 1993). Por outro lado, só é possível conservar os processos ecológicos associados aos artrópodes promovendo a gestão correcta dos seus habitats. Para tal, é necessária uma correcta identificação e caracterização das suas comunidades de forma a promover a sua boa gestão. Durante os últimos anos têm sido realizados nos Açores vários estudos de inventariação e caracterização ecológica dos artrópodes em alguns dos habitats mais importantes destas ilhas: i) habitat cavernícola (Borges & Oromí, 1994); ii) pastagens semi-naturais e intensivas (Borges & Brown, 2001, 2003, 2004); iii) florestas nativas dos Açores (Borges et al., 2000, 2005a, b, 2006; Ribeiro et al., 2005). No entanto, na diversidade de usos do solo das ilhas açoreanas, as fruteiras constituem um habitat mal estudado em termos da cadeia trófica de artrópodes (contudo ver Oliveira, 2002). […]" (da Introdução).
- Effects of a short-term temperature increase on arthropod communities associated with pasturesPublication . Wallon, Sophie; Tsafack, Noelline; Pozsgai, Gabor; Melo, Catarina; Borges, Paulo A. V.; Elias, R.B.ABSTRACT: The impact of climate change on islands is expected to cause dramatic consequences on native biodiversity. However, limited data are available for arthropod communities in island agroecosystems. In this study, we simulate a small-scale climatic change (average of +1.2°C), using Open Top Chambers (OTCs) in forage crops in the Azores Archipelago (Portugal) and test the responses of arthropod communities associated with intensively-managed pastures. At three sites, twenty 1 x 1 m plots were established: 10 treatment plots with OTCs and 10 control plots. Arthropods were sampled with pitfall traps on two sampling events (winter and summer of 2020). When considering all species collected, arthropods' abundance was lower in OTCs. Specific taxa, namely spiders and beetles, showed a fast response to the OTCs' presence. The assemblage of non-indigenous spiders well adapted to pastures showed a significant difference in diversity with a slightly greater richness, but lower abundance inside the warmer plots. However, the presence of OTCs resulted in a decrease in beetle richness and abundance. This decline may be attributed to the multiple effects of warming. Therefore, it is imperative to conduct further investigations to elucidate the ecological processes that underlie the observed patterns.
- Extinction debt on oceanic islandsPublication . Triantis, Kostas A.; Borges, Paulo A. V.; Ladle, Richard J.; Hortal, Joaquín; Cardoso, Pedro; Gaspar, Clara; Dinis, Francisco; Pereira, Enésima; Silveira, Lúcia M. A.; Gabriel, Rosalina; Melo, Catarina; Santos, Ana M. C.; Amorim, Isabel R.; Ribeiro, Sérvio P.; Serrano, Artur R. M.; Quartau, José A.; Whittaker, Robert J.Habitat destruction is the leading cause of species extinctions. However, there is typically a time-lag between the reduction in habitat area and the eventual disappearance of the remnant populations. These “surviving but ultimately doomed” species represent an extinction debt. Calculating the magnitude of such future extinction events has been hampered by potentially inaccurate assumptions about the slope of species–area relationships, which are habitat- and taxon-specific. We overcome this challenge by applying a method that uses the historical sequence of deforestation in the Azorean Islands, to calculate realistic and ecologically-adjusted species–area relationships. The results reveal dramatic and hitherto unrecognized levels of extinction debt, as a result of the extensive destruction of the native forest:>95%, in<600 yr. Our estimations suggest that more than half of the extant forest arthropod species, which have evolved in and are dependent on the native forest, might eventually be driven to extinction. Data on species abundances from Graciosa Island, where only a very small patch of secondary native vegetation still exists, as well as the number of species that have not been found in the last 45 yr, despite the extensive sampling effort, offer support to the predictions made. We argue that immediate action to restore and expand native forest habitat is required to avert the loss of numerous endemic species in the near future.
- Invasibility and species richness of island endemic arthropods: a general model of endemic vs. exotic speciesPublication . Borges, Paulo A. V.; Lobo, Jorge M.; Azevedo, Eduardo B.; Gaspar, Clara; Melo, Catarina; Nunes, Luis V.This paper has two objectives. First, we examine how a variety of biotic, abiotic and anthropogenic factors influence the endemic and introduced arthropod richness on an oceanic island. Second, we look at the relationship between the endemic and introduced arthropod richness, to ask whether areas with high levels of endemic species richness deter invasions.
- List of arthropods (Arthropoda)Publication . Borges, Paulo A. V.; Vieira, Virgilio; Amorim, Isabel R.; Bicudo, Nuno; Fritzén, Niclas; Gaspar, Clara; Heleno, Ruben; Hortal, Joaquín; Lissner, Jorgen; Logunov, Dmitri; Machado, António; Marcelino, José; Meijer, Seline S.; Melo, Catarina; Pereira, Enésima; Moniz, João; Pereira, Fernando E. A. P.; Santos, Ana M.; Simões, Ana M.; Torrão, Elisabete
- List of arthropods (Arthropoda)Publication . Borges, Paulo A. V.; Vieira, Virgilio; Dinis, Francisco; Jarroca, Sandra; Aguiar, Carlos; Amaral, João; Aarvik, Leif; Ashmole, Philip; Ashmole, Myrtle; Amorim, Isabel R.; André, Genage; Argente, Maria C.; Arraiol, Anabela; Cabrera, Almudena; Diaz, Suraya; Enghoff, H.; Gaspar, Clara; Pereira, Enésima; Gisbert, Hugo M.; Gonçalves, Paula; Lopes, David João Horta; Melo, Catarina; Mota, José A.; Oliveira, Odelta; Oromí, Pedro; Pereira, Fernando E. A. P.; Pombo, Dalberto; Quartau, José A.; Ribeiro, Sérvio P.; Rodrigues, Ana C.; Santos, Ana M. C.; Serrano, Artur R. M.; Simões, Ana M.; Soares, António O.; Sousa, António B.; Vieira, Luís; Vitorino, Álvaro; Wunderlich, Joerg
- New records and detailed distribution and abundance of selected arthropod species collected between 1999 and 2011 in Azorean native forestsPublication . Borges, Paulo A. V.; Gaspar, Clara; Crespo, Luís C.; Rigal, François; Cardoso, Pedro; Pereira, Fernando; Rego, Carla; Amorim, Isabel; Melo, Catarina; Aguiar, Carlos; André, Genage; Pereira, Enésima; Ribeiro, Sérvio P.; Hortal, Joaquín; Santos, Ana M. C.; Barcelos, Luís Miguel Duarte; Enghoff, H.; Mahnert, Volker; Pita, Margarida T.; Ribes, Jordi; Baz, Arturo; Sousa, António B.; Vieira, Virgilio; Wunderlich, Jörg; Parmakelis, Aristeidis; Whittaker, Robert J.; Quartau, José A.; Serrano, Artur R. M.; Triantis, Kostas A.BACKGROUND: In this contribution we present detailed distribution and abundance data for arthropod species identified during the BALA – Biodiversity of Arthropods from the Laurisilva of the Azores (1999-2004) and BALA2 projects (2010-2011) from 18 native forest fragments in seven of the nine Azorean islands (all excluding Graciosa and Corvo islands, which have no native forest left). NEW INFORMATION: Of the total 286 species identified, 81% were captured between 1999 and 2000, a period during which only 39% of all the samples were collected. On average, arthropod richness for each island increased by 10% during the time frame of these projects. The classes Arachnida, Chilopoda and Diplopoda represent the most remarkable cases of new island records, with more than 30% of the records being novelties. This study stresses the need to expand the approaches applied in these projects to other habitats in the Azores, and more importantly to other less surveyed taxonomic groups (e.g. Diptera and Hymenoptera). These steps are fundamental for getting a more accurate assessment of biodiversity in the archipelago.