Browsing by Issue Date, starting with "2020-07"
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- Cold Storage Effects on Fitness of the Whitefly Parasitoids Encarsia sophia and Eretmocerus hayatiPublication . Kidane, Dawit; Ferrante, Marco; Man, Xiao-Ming; Liu, Wan-Xue; Wan, Fang-Hao; Yang, Nian-WanSuccessful biological control of the whitefly Bemisia tabaci involves the mass rearing of biocontrol agents in large numbers for field release. Cold storage of the biocontrol agents is often necessary to provide a sufficient number of biocontrol agents during an eventual pest outbreak. In this study, the fitness of two whitefly parasitoids Encarsia sophia Girault and Dodd (Hymenoptera: Aphelinidae) and Eretmocerus hayati Zolnerowich and Rose (Hymenoptera: Aphelinidae) was evaluated under fluctuating cold storage temperatures. The emergence rate of old pupae of either species was not affected when stored at 12, 10, 8 and 6 °C for 1 week. Cold storage had no effect on the longevity of the emerging adult En. sophia except young pupae stored at 4 °C, while Er. hayati was negatively affected after 2 weeks of storage time at all temperatures. Parasitism by adults emerging from older pupae stored at 12 °C for 1 week was equivalent to the control. Combined with the results for the emergence time, we suggest that the old pupal stage of En. sophia and Er. hayati could be stored at 12 and 10 °C, respectively (transferred every 22 h to 26 ± 1 °C for 2 h), for 1 week, with no or little adverse effect.
- Macrobiological Degradation of Esterified Wood with Sorbitol and Citric AcidPublication . Treu, Andreas; Nunes, Lina; Larnøy, ErikThere is a need for new solutions in wood protection against marine wood borers and termites in Europe. A new solution could be the esterification of wood with sorbitol and citric acid (SCA) since these are inexpensive and readily available feedstock chemicals and have shown protective properties against fungal wood degradation in earlier studies and prevented macrobiological degradation, as shown in this study. Protection of wood products in the marine environment lacks available wood preservatives that are approved for marine applications. Termite infestation is opposed mainly by biocide treatments of wood. Several wood modification systems show high resistance against both marine borers and subterranean termites. However, the existing commercialized wood modification products are costly. Both macrobiological forms of degradation represent a great threat for most European wood species, which are rapidly and severely degraded if not properly treated. This study investigated esterified wood in standard field trials against marine wood borers, and against subterranean termites in laboratory trials in a no-choice and choice test. The treatment showed good resistance against wood borers in the marine environment after one season and against subterranean termites in the laboratory after eight weeks. The low termite survival rate (SR) in the no-choice test during the first week of testing indicates a mode of action that is incomparable to other wood modification treatments.
- Increase of insular exotic arthropod diversity is a fundamental dimension of the current biodiversity crisisPublication . Borges, Paulo A. V.; Rigal, François; Ros‐Prieto, A.; Cardoso, PedroA dramatic insect decline has been documented on the grasslands and forests of European or North American mainland. Yet, other parts of the world and other ecosystems remain much less studied with unknown patterns. Using a unique time-series dataset, we investigate recent trends on abundance and richness of arthropods sampled in Azorean native forest over 6 years (2013–2018). We test the hypothesis that biodiversity erosion drivers are changing the diversity and relative species abundance structure (species abundance distribution, SAD) of endemics, native non‐endemics and exotic species over time. We also examine temporal trends in abundance for each individual species. In contrast with mainland studies, we observed no decline in overall arthropod diversity, but a clear increase in the diversity of exotic arthropods and some evidence of a tendency for decreasing abundance for some endemic species. We also document stronger species turnover for exotic species, but no specific changes in the SAD. We argue that many changes, particularly in unique systems such as islands, will be noticed not at the richness but mostly at compositional level. Special attention should be given to exotic species which are known to be one of the major drivers of biodiversity erosion on islands.
- Jardins Históricos dos Açores, um mundo por descobrir…Publication . Gil, Ana Cristina Correia, dir.; Fialho, Adolfo Fernando da Fonte, ed.
- Insect occurrence in agricultural land‐uses depends on realized niche and geographic range propertiesPublication . Waldock, Conor A.; De Palma, Adriana; Borges, Paulo A. V.; Purvis, AndyGeographic range size predicts species' responses to land-use change and intensification, but the reason why is not well established because many correlates of larger geographic ranges, such as realized niche breadth, may mediate species' responses to environmental change. Agricultural land uses (hereafter 'agroecosystems') have warm, dry and more variable microclimates than do cooler and wetter mature forests, so are predicted to filter for species that have warmer, drier and broader fundamental and realized niches. To test these predictions, we estimated species' realized niches, for temperature and precipitation, and geographic range sizes of 764 insect species by matching GBIF occurrence records to global climate layers, and modelled how species presence/absence in mature forest and nearby agroecosystems depend on species' realized niches or geographic ranges. The predicted species niche effects consistently matched the expected direction of microclimatic transition from mature forest to agroecosystems. We found a clear signal that species with preference for warmer and drier climates were more likely to be present in agroecosystems. In addition, the probability that species occurred in different land-use types was predicted better by species' realized niche than their geographic range size. However, niche effects are often context-dependent and varied amongst studies, taxonomic groups and regions used in this analysis: predicting which particular aspects of species' realized niche cause sensitivity to land-use change, and the underpinning mechanisms, remains a major challenge for future research and multiple components of species' realized niches may be important to consider. Using realized niches derived from open-source occurrence records can be a simple and widely applicable tool to help identify when biodiversity responds to the microclimate component of land-use change.
- The fruit flies (Diptera, Tephritidae) of the Madeira archipelago with the description of a new Oedosphenella FreyPublication . Penado, Andreia; Smit, John T.; Aguiar, António F.; Cravo, Délia; Rego, Carla; Santos, Renata; Boieiro, MárioA checklist of the tephritid fauna (Diptera: Tephritidae) from Madeira archipelago is presented, including 17 known species and new distribution records for Porto Santo and Desertas Islands. An identification key to Madeira Tephritidae species with detailed illustrations is also provided. A new species of Oedosphenella Frey 1936, discovered in Madeira Island in 2004, is described as Oedosphenella bob sp. n. This genus is redefined and a key to the known species is provided. Comparative morphological analysis revealed that Bevismyia basuto Munro 1957 from Malawi should be included in the genus Oedosphenella. Therefore, we consider the genus name Oedosphenella Frey 1936 to be a senior synonym of Bevismyia Munro 1957 syn.n.
- Potential Role of Native Arbuscular Mycorrhizal Fungi (AMF) in the Restoration of LaurisilvaPublication . Melo Drumonde, Catarina; Borges, Paulo A. V.; Freitas, Helena; Nunes, Luis V.The beneficial association of seedlings with arbuscular mycorrhizal fungi (AMF) is thought to improve early tree establishment through increased uptake of poorly labile soil nutrients (particularly P) and enhancing plant tolerance to biotic and abiotic factors. Seedlings of Juniperus brevifolia, an endemic woody plant of the Azores archipelago with potential commercial value, was grown in the nursery with and without inoculation by a commercial plant growth promoter consisting of AMF isolated from the Azores (MICOazorica). Treatments were arranged in a randomized complete block design in a greenhouse. At six months after planting, all AMF-inoculated plants were colonized. The percentage of colonization varied between 46% and 96% (Mean 70%). At harvest, all physical parameters were significantly greater in AMF-inoculated plants relative to uninoculated plants. Based on the obtained results, we strongly advise the use of native AMF, in strategies used in restoration programs in the Azores.
- Decomposing the Causes for Niche Differentiation Between Species Using HypervolumesPublication . Carvalho, José Carlos; Cardoso, PedroHutchinson’s n-dimensional hypervolume concept holds a central role across different fields of ecology and evolution. The question of the amount of hypervolume overlap and differentiation between species is of great interest to understand the processes that drive niche dynamics, competitive interactions and, ultimately, community assembly. A framework is proposed to decompose overall differentiation among hypervolumes into two distinct components: niche shifts and niche contraction/expansion processes. Niche shift corresponds to the replacement of space between the hypervolumes occupied by two species, whereas niche contraction/expansion processes correspond to net differences between the amount of space enclosed by each hypervolume. A procedure to implement non-continuous trait data in the estimation of n-dimensional hypervolumes is proposed. Hypervolumes were constructed for three Darwin’ finches, Geospiza conirostris, Geospiza magnirostris, and Geospiza difficilis using intraspecific trait data. Results showed that significant niche shifts, not niche contraction, occurred between G. conirostris and G. magnirostris in Genovesa island, where they live in sympatry. This means that G. conirostris occupied a different niche space and not a reduced space on Genovesa. G. difficilis was well differentiated from the other two species. The proposed framework allows disentangling different processes underlying niche partitioning between coexisting species. This framework offers novel insights to understand the drivers of niche partitioning strategies among coexisting species.
- Building a robust, densely-sampled spider tree of life for ecosystem researchPublication . Macías-Hernández, Nuria; Domènech, Marc; Cardoso, Pedro; Emerson, Brent C.; Borges, Paulo A. V.; Lozano-Fernandez, Jesús; Paulo, Octávio S.; Vieira, Ana; Enguídanos, Alba; Rigal, François; Rosário, Isabel Amorim do; Arnedo, Miquel A.Phylogenetic relatedness is a key diversity measure for the analysis and understanding of how species and communities evolve across time and space. Understanding the nonrandom loss of species with respect to phylogeny is also essential for better-informed conservation decisions. However, several factors are known to influence phylogenetic reconstruction and, ultimately, phylogenetic diversity metrics. In this study, we empirically tested how some of these factors (topological constraint, taxon sampling, genetic markers and calibration) affect phylogenetic resolution and uncertainty. We built a densely sampled, species-level phylogenetic tree for spiders, combining Sanger sequencing of species from local communities of two biogeographical regions (Iberian Peninsula and Macaronesia) with a taxon-rich backbone matrix of Genbank sequences and a topological constraint derived from recent phylogenomic studies. The resulting tree constitutes the most complete spider phylogeny to date, both in terms of terminals and background information, and may serve as a standard reference for the analysis of phylogenetic diversity patterns at the community level. We then used this tree to investigate how partial data affect phylogenetic reconstruction, phylogenetic diversity estimates and their rankings, and, ultimately, the ecological processes inferred for each community. We found that the incorporation of a single slowly evolving marker (28S) to the DNA barcode sequences from local communities, had the highest impact on tree topology, closely followed by the use of a backbone matrix. The increase in missing data resulting from combining partial sequences from local communities only had a moderate impact on the resulting trees, similar to the difference observed when using topological constraints. Our study further revealed substantial differences in both the phylogenetic structure and diversity rankings of the analyzed communities estimated from the different phylogenetic treatments, especially when using non-ultrametric trees (phylograms) instead of time-stamped trees (chronograms). Finally, we provide some recommendations on reconstructing phylogenetic trees to infer phylogenetic diversity within ecological studies.
- Using Open Remote Sensing and Geographic Data for SMART Monitoring of Nature-based TOURISM in the Azores Islands Natural Parks : towards (more) SustainabilityPublication . Gil, Artur José Freire; Fernández-Urrutia, Manuel; Tiago, Flávio Borges; Tiago, Maria TeresaA remote sensing-based operational tool using Sentinel-2 and Landsat-8 free and open access satellite multispectral data, and based on the Google Earth Engine (GEE) platform, is under development for monitoring land-cover/land-use changes in the Azores Islands Natural Park.
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