Browsing by Issue Date, starting with "2020-03"
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- Thallus structural alterations in green-algal lichens as indicators of elevated CO₂ in a degassing volcanic areaPublication . Bernardo, Filipe Miguel; Rocha, Tânia; Branquinho, Cristina; Garcia, Patrícia; Rodrigues, ArmindoWe hypothesize that the thalli of the green-algal, CO₂-sensitive lichen Usnea rubicunda (Stirton) undergo significant structural alterations as a biological response indicating increased CO₂ emissions. To test that, U. rubicunda thalli were transplanted from a reference site with no volcanism into 36 sites distributed within the volcanically active Furnas caldera, encompassing the gradient of soil diffuse CO₂ degassing areas (700 t d⁻¹ of hydrothermal CO₂). After 6 months of exposure in similar macroclimatic conditions, both Furnas transplants and samples kept at the reference site were retrieved for histology to assess thalli structure and the proportion between the symbionts. On average, cross-sections of Furnas thalli were significantly thicker than reference, owing mostly to the fungal layers of medulla and central cord. The latter occupied a significantly greater than reference relative volumetric density despite a smaller than reference relative percentage of algal occupation on Furnas thalli. These results reveal a positive and time-integrated response of U. rubicunda to the greater availability of CO₂ from hydrothermal emissions in the volcanic environment, translated in greater efficiency of the algae in sustaining the fungal biomass. Histomorphometric structural alterations in the heteromerous thalli of U. rubicunda are suitable response biomarkers with potential to indicate a global rise of CO₂ levels in natural environments.
- Valuable but vulnerable : Over-fishing and under-management continue to threaten groupers so what now?Publication . Mitcheson, Yvonne Sadovy de; Linardich, Christi; Barreiros, João P.; Ralph, Gina M.; Aguilar-Perera, Alfonso; Afonso, Pedro; Erisman, Brad E.; Pollard, David A.; Fennessy, Sean T.; Bertoncini, Áthila A.; Nair, Rekha J.; Rhodes, Kevin L.; Francour, Patrice; Brulé, Thierry; Samoilys, Melita A.; Ferreira, Beatrice P.; Craig, MatthewAmong threats to marine species, overfishing has often been highlighted as a major contributor to population declines and yet fishing effort has increased globally over the past decade. This paper discusses the decadal reassessment of groupers (family Epinephelidae), an important and valuable group of marine fishes subjected to high market demand and intense fishing effort, based on IUCN criteria. Allowing for uncertainty in the status of species listed as Data Deficient, 19 species (11.4%) are currently assigned to a “threatened” category. This first reassessment for a large marine fish taxon permits an evaluation of changes following the original assessments, provides a profile of the current conservation condition of species, identifies the challenges of assessing conservation status, and highlights current and emerging threats. Measures needed to reduce threats and lessons learned from conservation efforts are highlighted. Present threats include intensifying fishing effort in the face of absent or insufficient fishery management or monitoring, growing pressures from international trade, and an inadequate coverage in effectively managed, sized, or located protected areas. Emerging threats involve expansion of fishing effort into deeper waters and more remote locations, shifts to previously non-targeted species, increases in the capture, marketing and use of juveniles, growing demands for domestic and international trade, and, potentially, climate change. Those species most threatened are larger-bodied, longer-lived groupers, most of which reproduce in spawning aggregations.
- Can School Children Support Ecological Research? Lessons from the Oak Bodyguard Citizen Science ProjectPublication . Castagneyrol, Bastien; Valdés-Correcher, Elena; Bourdin, Audrey; Barbaro, Luc; Bouriaud, Olivier; Branco, Manuela; Centenaro, Giada; Csóka, György; Duduman, Mihai-Leonard; Dulaurent, Anne-Maïmiti; Eötvös, Csaba B.; Faticov, Maria; Ferrante, Marco; Fürjes-Mikó, Ágnes; Galmán, Andrea; Gossner, Martin M.; Harvey, Deborah; Howe, Andy G.; Kaennel-Dobbertin, Michèle; Koricheva, Julia; Löveï, Gábor L.; Lupaștean, Daniela; Milanović, Slobodan; Mrazova, Anna; Opgennoorth, Lars; Pitkänen, Juha-Matti; Popović, Marija; Roslin, Tomas V.; Scherer-Lorenzen, Michael; Sam, Katerina; Tahadlová, Markéta; Thomas, Rebecca; Tack, Ayco J. M.Scientific knowledge in the field of ecology is increasingly enriched by data acquired by the general public participating in citizen science (CS) programs. Yet, doubts remain about the reliability of such data, in particular when acquired by schoolchildren. We built upon an ongoing CS program, Oak Bodyguards, to assess the ability of schoolchildren to accurately estimate the strength of biotic interactions in terrestrial ecosystems. We used standardized protocols to estimate attack rates on artificial caterpillars and insect herbivory on oak leaves. We compared estimates made by schoolchildren with estimates made by professional scientists who had been trained in predation and herbivory assessments (henceforth, trained scientists), and trained scientists’ estimates with those made by professional scientists with or without expertise (untrained) in predation or herbivory assessment. Compared with trained scientists, both schoolchildren and untrained professional scientists overestimated attack rates, but assessments made by the latter were more consistent. Schoolchildren tended to overestimate insect herbivory, as did untrained professional scientists. Raw data acquired by schoolchildren participating in CS programs therefore require several quality checks by trained professional scientists before being used. However, such data are of no less value than data collected by untrained professional scientists. CS with schoolchildren can be a valuable tool for carrying out ecological research, provided that the data itself is acquired by professional scientists from material collected by citizens.
- Primeira citação de Cydalima perspectalis (Walker, 1859) para a ilha de São Miguel, Açores (Portugal) (Lepidoptera: Crambidae)Publication . Vieira, VirgilioA traça-do-buxo Cydalima perspectalis (Walker, 1859) é citada pela primeira vez para a ilha de São Miguel, arquipélago dos Açores. É uma espécie originária da Ásia Oriental, invasora, que causa danos graves em diferentes plantas ornamentais do género Buxus L. na Europa. Também, são apresentadas algumas notas sobre a distribuição e ecologia desta espécie.
- Distribution of ecosystem services within oilseed rape fields : Effects of field defects on pest and weed seed predation ratesPublication . González, Ezequiel; Seidl, Miroslav; Kadlec, Tomáš; Ferrante, Marco; Knapp, MichalFrequent extreme weather events, which jeopardize agriculture by affecting crop health, characterize the ongoing climate change. Temporary patches where sown plants are poorly developed (hereafter “field defects”) are likely to increase with climate change and can be colonized by other plant species. Although perennial non-crop habitats can act as refuges for beneficial insects in agricultural landscapes and increase ecosystem services (ESs) in neighbouring arable fields, the relevance of field defects is unknown. Here, we quantified two ESs (pest and weed seed predation) in field defects within oilseed rape crops and related the ES levels with the activity-density of ground beetles and temperature. In 10 fields, we used artificial caterpillars made of plasticine and seed cards of two weed species (Taraxacum sp. and Stellaria sp.) to quantify the ESs in two sampling periods (spring and summer) and three habitat types: field defects, crops grown in standard conditions (field interiors) and crop-defect boundaries. Ground beetles were sampled using pitfall traps and classified into feeding guilds and body-size classes. Insects and mammals were the main pest predators, and predation increased in summer but did not differ among habitats. Seed predation rates for both species were significantly higher in summer. Predation upon Taraxacum seeds was higher in the field interiors, whereas the predation rate upon Stellaria seeds was significantly higher in the field interiors and defects compared to that in the crop-defect boundaries. The predation rate by insects increased with the activity-density of the medium- and large-sized carnivorous carabids, whereas the seed predation rate for both weed species was positively related to the activity-density of medium-sized herbivorous carabids. Finally, the mean and maximum temperatures were negatively linked to the predation rates on artificial caterpillars and seeds of Taraxacum, respectively. Our results suggest that these ephemeral habitats are not related to a strong decrease in ecosystem services; thus, field defects may not cause substantial changes in ES provisioning. We confirmed that ground beetles are important providers of both investigated ESs and showed that microclimatic conditions might play an important role in the regulation of ESs in agroecosystems.
- The Azorean edible abalone Haliotis tuberculata, an alternative heavy metal-free marine resource?Publication . Torres, Paulo; Rodrigues, Armindo; Prestes, Afonso L.; Neto, Ana I.; Álvaro, Nuno V.; Martins, Gustavo M.Abalones are considered a delicacy and exploited for food worldwide. In many places, overfishing has led to the decimation of wild stocks and many are now reared in aquaculture systems. In the Azores, there is no tradition of eating abalones and Haliotis tuberculata stocks are still virtually untouched. However, as tourism in the islands grows and the stocks of other shellfish diminish, there is an increasing pressure to find alternative edible resources, leading to a rising interest in abalones. According to previous studies performed in the region, other edible species, including the local highly appreciated limpets and the giant barnacle, present high concentration levels of some heavy metals, which has been attributed to the volcanic origin of the islands. Here we analysed the metal content in the edible tissue of Haliotis tuberculata from São Miguel Island, Azores. The potential human health risks due to its consumption was assessed by estimating the average daily intake (EDI) and target hazard quotient (THQ) of metals. Similarly to other organisms in the Azores, abalones have higher than normal levels of some heavy metals, particularly cadmium, reflecting a local natural source that should be closely monitored from a public health point of view.
- A Green and Simple Protocol for Extraction and Application of a Peroxidase-Rich Enzymatic ExtractPublication . Rosa, Gonçalo P.; Barreto, Maria do Carmo; Pinto, Diana C. G. A.; Seca, Ana M. L.Recently there is a great social expectation that scientists should produce more sustainable and environmentally friendly chemical processes. Within this necessity, biocatalysis presents many attractive features because reactions are often performed in water, under mild conditions, the catalyst is biodegradable and can be obtained from renewable raw materials. In this work, we propose a simple, rapid and low-cost method for the preparation and application of an enzymatic extract from turnip root. The protocol described includes (1) the preparation of the enzymatic extract, (2) the procedure for the assessment of the more favorable working parameters (temperature, pH) and (3) the methodology for the application of the extract as the catalyst for biotransformation reactions. We anticipate that the protocol in this research will provide a simple way for obtaining an enzymatic extract which can operate efficiently under mild conditions and can effectively catalyze the biotransformation of simple phenols.
- Primeiro registo de Thera cupressata (Geyer, [1831]) para as ilhas dos Açores (Portugal) (Lepidoptera: Geometridae)Publication . Vieira, VirgilioA traça-do-cipreste Thera cupressata (Geyer, [1831]) é citada pela primeira vez para a ilha de São Miguel, arquipélago dos Açores (Portugal). É uma borboleta originária da Europa. Também, são apresentadas breves notas sobre a distribuição e ecologia desta espécie.
- Biochemical study of attached macroalgae from the Madeira Archipelago and beach-cast macroalgae from the Canary Islands: multivariate analysis to determine bioresource potentialPublication . Nunes, Nuno; Valente, Sofia; Ferraz, Sónia; Barreto, Maria do Carmo; Carvalho, Miguel A. A. Pinheiro deFifteen attached macroalgae from the Madeira Archipelago, comprising three green, three red and nine brown algal species, as well as two beach-cast macroalgal samples, collected along the north shore of Gran Canaria, were assessed for their biochemical properties. The analysis included the determination of total minerals, total carbohydrates, protein, lipids, chlorophyll a, total carotenoids, total phenolic content, fucoxanthin and phycobilins (allophycocyanin, phycocyanin and phycoerythrin). The results showed a high variability of biochemical composition, allowing for the targetting of specific bioresources for particular purposes, including functional foods. This work provides the foundation for a biorefinery strategy implementation plan, for which specific macroalgae may be targeted for valuable and beneficial compounds.
- Mapping and assessing land cover/land use and aboveground carbon stocks rapid changes in small oceanic islands' terrestrial ecosystems: A case study of Madeira Island, Portugal (2009–2011)Publication . Massetti, Andrea; Gil, Artur José FreireSmall islands face environmental issues directly or indirectly related to land cover/land use changes (LCLUC), such as natural hazards, climate change, loss of biodiversity and proliferation of invasive alien species, some of which are caused by direct human exploitation. A Land Cover/Land Use Change (LCLUC) detection approach based on PCA and vegetation indices derived from low cost high-resolution RapidEye multispectral satellite data and available vegetation maps was developed to assess vegetated/forested aboveground carbon stocks and their changes in Madeira Island, Portugal, for the period between December 2009 and August 2011 due to catastrophic events occurred in 2010. During this period, the identified LCLUC revealed a relevant decrease of vegetated areas (especially those dominated by native/endemic communities) substituted by increases of non-vegetated and human-managed vegetated/forested areas. In particular, there was a decrease of 2% of vegetated areas, 30% of which were represented by native/endemic vegetation. The largest and most accurate LCLUC detected were used to estimate changes in aboveground biomass carbon (AGC) stocks. In 2010 more than 25,000 Mg of AGC stocks may have been released. Both relevant LCLUC and AGC stocks depletion in such short period of time may have been strongly enhanced by two catastrophic events that affected Madeira in February (flashflood and landslides) and August 2010 (wildfires). This straightforward and cost-effective methodological approach may be successfully applied in remote territories such as islands or mountainous areas, where the logistic and economic costs associated to periodic and standard airborne remote sensing campaigns for mapping, assessing and monitoring aboveground biomass carbon stocks are generally unaffordable for most decision-makers and land managers in these territories.
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