Repositório da Universidade dos Açores
Repositório Institucional da Universidade dos Açores
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Restoring functional farmland biodiversity for biological pest control
Publication . Wyckhuys, Kris; Bushley, Kathryn; Gratton, Claudio; Gurr, Geoff; Pozsgai, Gabor; Tscharntke, Teja; Wanger, Thomas; Lu, Yanhui; Elkahky, Maged
ABSTRACT: Roughly 40% of global agri-food production is lost to pests during an era when productivity gains are essential to humanity. Restoring farmland biodiversity for conservation biological control offers potential to secure win-win outcomes for yield and the environment. However, achieving this is hindered by gaps in our understanding of agrobiodiversity, including a lack of data on the occurrence, identity, and interactions of farm-dwelling (plant, animal, microbial) biota. Limited interdisciplinary collaboration and weak policy frameworks exacerbate these issues. Comprehensive data capture using standardized metrics, universal protocols, farmer–scientist cooperation, and next-generation tools could consolidate the evidence base on which to reform farming practice. This will involve ecologists stepping outside their comfort zones to promote behavioral change and make ecological intensification a reality.
Origanum vulgare subsp. virens (Hoffmanns. & Link) Bonnier & Layens Essential Oils: Chemotypes and Bioactivity as Antifungal, Antifeeding and Enzyme Inhibitors
Publication . Ferreira, Rui; Martins, Mariana; Santos, Vanessa; Sardinha, Duarte; Tavares, Wilson; Sabina, Samuel; Espinel, Guacimara; Barreto, Maria Carmo; Oliveira, Luísa; Cabrera, Raimundo; Castilho, Paula; Kitić, Dušanka; Šavikin, Katarina; Randjelović, Milica
ABSTRACT: Essential oils (EOs) from the leaves of Origanum vulgare subsp. virens (Hoffmanns. & Link) Bonnier & Layens, representing three chemotypes—thymol-rich, carvacrol-rich, and a mixed thymol–carvacrol type—were chemically characterized and comparatively assessed for their antifungal, insecticidal, and enzyme-inhibitory activities. This integrated approach provides a comparative assessment of all three chemotypes across multiple biological models, including phytopathogenic fungi, insect bioassays, and key enzyme targets. All EOs displayed antifungal activity for the tested phytopathogenic fungi (Alternaria alternata, Botrytis cinerea, and Fusarium oxysporum) at concentrations above 0.5 mg/mL, with the thymol-rich chemotype showing the highest activity. The minimum inhibition concentration for Oidium farinosum conidial growth was determined and found to be similar for thymol and carvacrol chemotypes and lower for the terpene mixture. Insect control activity was evaluated by an antifeeding assay, where carvacrol and especially thymol chemotypes can be classified as feeding deterrents. EOs and standards revealed a weak toxicity against Ceratitis capitata, with less than 20% mortality at a concentration of 50 mg/mL, and both chemotypes were found to be ineffective in preventing egg deposition. The acetylcholinesterase (AChE) inhibition assay revealed that carvacrol had the greatest inhibitory effect on AChE, followed by EOs, and, finally, thymol. Regarding the α- and β-glucosidase (α- and β-GLU) inhibitory assays, thymol had the strongest inhibitory effect on α-GLU, while plant β-GLU was not inhibited by the standards or OEs.
Spatially explicit assessment of carbon storage and sequestration in forest ecosystems
Publication . almeida, bruna; Monteiro, Luís; Tiengo, Rafaela; Freire Gil, Artur José; Cabral, Pedro
ABSTRACT: Forests play an important role in the global carbon cycle, making accurate assessments of carbon dynamics essential for effective forest management and climate change mitigation strategies. This research examines the spatiotemporal patterns of carbon storage and sequestration (CSS) in forests' aboveground biomass using satellite data, machine learning (Support Vector Machines), carbon modelling and spatial statistics. The methodology follows a two-step classification process: (i) binary forest classification and (ii) forest type classification, mapping seven forest types within two main categories - Broadleaves (Quercus suber, Quercus ilex, Eucalyptus sp., and other species) and Coniferous (Pinus pinaster, Pinus pinea, and other species). We analyzed the relationship between forest type and CSS at the Nomenclature of Territorial Units for Statistics (NUTS) III level and identified spatial clusters, outliers, and hot and cold spots of carbon sequestration at the municipal level across mainland Portugal. The broadleaved category demonstrated the highest classification accuracy in both years, decreasing slightly from 90.3 % in 2018 to 89 % in 2022, while the Coniferous group had the lowest accuracy, declining from 84.1 % in 2018 to 83.6 % in 2022. Anselin's Local Moran's I identified clusters of carbon sequestration, while the Getis-Ord Gi analysis confirmed these findings, revealing statistically significant hotspots of carbon sequestration in the northern and central regions and cold spots in the southern region. By providing insights at the sub-regional and municipal levels, this study offers a robust framework to support sustainable forest management and climate change mitigation strategies. Moreover, it can assist decision-makers in prioritizing natural capital, and developing nature-based solutions to tackle climate change and biodiversity loss.
Species traits may predict extinction risk of Azorean endemic arthropods
Publication . Oyarzabal da Silva, Guilherme; Cardoso, Pedro; Rigal, François; Canelas Boieiro, Mário Rui; Coelho dos Santos, Ana Margarida; Amorim do Rosário, Isabel; Malumbres-Olarte, Jagoba; Costa, Ricardo; Lhoumeau, Sébastien Georges André; Pozsgai, Gabor; Gabriel, Rosalina; Borges, Paulo; Littlewood, Nick; Bahlai, Christie
ABSTRACT: Oceanic islands, recognised for their isolation, high endemic species richness and unique evolutionary paths compared with their continental counterparts, are extremely susceptible to anthropogenic activities. The fragmentation of island habitats and disruption of native ecosystems has increased the risk of extinction for many endemic species, including arthropods. Extinction is not random, and some species traits may increase the probability of species entering an extinction trajectory. Studying species traits alongside International Union for Conservation of Nature (IUCN) threat levels may offer valuable insights into their vulnerability and inform targeted conservation strategies. Here, we aim to test the predictability of IUCN threat categories and conservation status based on endemic Azorean arthropods' functional traits: body size, trophic group and vertical strata occupancy. We demonstrate that species with limited vertical occupancy, particularly those restricted to ground level, are more vulnerable to extinction than those that inhabit the forest canopy. Contrary to our expectations, body size and trophic group did not appear to be direct predictors of the threat level. Overall, our findings underscore previous and ongoing effects of human activities in island ecosystems. Hence, we emphasise the need to look at species traits as predictors of future extinctions in endemic island arthropods.
The Ripple Effects of Climate Change on Tibetan Alpine Arthropods
Publication . Oyarzabal da Silva, Guilherme; Borges, P.A.V.