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- Mass Timber Buildings: The associated risks of rainwater exposure during construction in the Portuguese climatePublication . Lima, Daniel F.; Duarte, Sónia; Branco, Jorge M.; Nunes, LinaThe increase in the number and complexity of wooden buildings creates a series of challenges, like moisture control and management during the construction phase. The risks associated with the direct exposure of timber elements to rain during construction depend on the severity of the climate and the specific details of each project and therefore must be analysed locally. In this context, the results of 16 weeks of moisture content monitorization of Cross Laminated Timber (CLT) floor-wall connection specimens exposed to the outdoors are presented and evaluated. The monitorization demonstrated that end-grain surfaces are the most sensitive to the action and movement of water in CLT and within a few days of exposure to rain reached alarming moisture content (MC>30 %), with water entrapment at the interface between elements, preventing drying in a reasonable time for construction workflow (MC>30 % after 39 days of drying). On the other hand, zones with faster drying exhibited severe physical damage such as delamination and cracks. Additionally, the study evaluates the feasibility of using satellite-obtained meteorological data to develop a degradation risk map (Scheffer Climate Index) for mainland Portugal. The high coefficient of determination (R2 ≥ 0.81) and model efficiency (EF ~ 0.80–0.90) demonstrate the reliability of the data. Finally, two degradation risk maps for mainland Portugal are presented.
- Molecular identification of the invasive subterranean termite Reticulitermes grassei (Blattodea: Rhinotermitidae) outside its known distribution: introduction routes and implications for pest management strategiesPublication . Hernández-Teixidor, David; Duarte, Sónia; Taheri, Ahmed; Borges, Paulo A. V.; Nunes, LinaDespite providing important ecosystem services, termites are also serious pests of wooden structures. Termites are highly adaptive organisms that cause concern as an invasive species. Predictions of the future spread of their distribution range due to factors such as climate change, urban growth, and global trade present new challenges to our capacity to protect our wood and wood-based materials and structures effectively. Reticulitermes grassei Clément, 1978 (Blattodea: Rhinotermitidae) is a subterranean termite native to the Iberian Peninsula and France, whose global distribution has widened over recent years. This article updates the distribution range of this species, confirming its identification in the Azores, Madeira, and Morocco through molecular analysis. The origin and consequences of these putative invasive populations are discussed in light of previously available data. The resulting network showed a highly structured base consisting of many haplotypes from the southern and southwestern Iberian Peninsula (Spain and Portugal), including those from Morocco (in natural landscapes) and Switzerland (in infrastructures). The more derived part of the network includes the haplotypes from southwest France, the northwest Iberian Peninsula, the United Kingdom, Azores, and Madeira, the last 3 being linked probably to human-mediated transportation events. The potential impacts of invasive subterranean termite populations expanding into new regions are concerning, especially in urban environments, and remain uncertain in natural areas. The challenges posed by these termites could be especially worrying in island ecosystems. Hence, it is crucial to implement early warning systems and monitoring programs in regions susceptible to subterranean termite invasions.
- Fichas de Espécies - ArthropodaPublication . Borges, Paulo A. V.; Vieira, Virgilio; Wallon, Sophie; Cardoso, Pedro; Picanço, Ana; Lamelas-López, Lucas; Amorim do Rosário, Isabel; Serrano, Artur; Nunes, Lina; Duarte, Sónia; Soares, António O.; Stüben, Peter E.; Borges, IsabelABSTRACT: Arthropods, and especially certain groupsof insects, due to their enormous specificrichness, abundance and fidelity tocertain habitats, among other factors, area fundamental tool in studies of ecologicalbio-indicators and biodiversity.
- Insulation Materials Susceptibility to Biological Degradation Agents: Molds and Subterranean TermitesPublication . Nunes, Lina; Duarte, Sónia; Parracha, João Luís; Jones, Dennis; Paulmier, Ivan; Kutnik, MagdalenaInsulation materials are fundamental for decreasing energy losses and guaranteeing thermal and acoustic comfort in buildings, which may significantly contribute to decreasing the energy consumption related with poor thermal building conditions. These insulation materials should have a low susceptibility to biological degradation agents to decrease the risks of degradation of other construction materials, as well as decrease possible health risks related with the development of noxious biological degradation agents regarding indoor air quality, for example, or decrease possible structural risks posed by those agents. The present study aimed at evaluating the susceptibility of several insulation materials to mold growth and subterranean termites’ attack. Insulation materials, including expanded polystyrene (EPS), mineral wool (MW), and expanded cork agglomerate (ICB), were tested against mold development, using maritime pine as a control. Three types of inoculations were made: (1) natural indoor inoculation; (2) artificial inoculation using Aspergillus niger and Penicillium funiculosum; and (3) artificial inoculation using Aureobasidium pullulans. The susceptibility of the insulation materials referred to, plus wood/glass fiber (WGF), was evaluated for two subterranean termite species: Reticulitermes grassei and Reticulitermes flavipes. The expanded cork agglomerate showed a higher susceptibility to molds than the other insulation materials tested. The remaining materials revealed a good performance, showing no growth or traces of growth of molds. All the materials tested showed susceptibility to subterranean termites, with both species being able to cross them to obtain access to the wood. However, wood/glass fiber showed a negative effect, which translated into lower survival rates and attack degrees of the wood. Some tested materials showed a good resistance to the development of biological degradation agents, namely an organic material (coconut fiber), a composite of organic and inorganic materials (WGF), and an inorganic material (EPS). These results indicate that it is possible to pursue the development of innovative and effective insulation materials with a low susceptibility to biological degradation agents, regardless of their organic or inorganic origin.