Browsing by Issue Date, starting with "2022-08"
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- Modelling the role of ground-true riparian vegetation for providing regulating services in a Mediterranean watershedPublication . Aparício, Bruno A.; Nunes, João Pedro; Bernard-Jannin, Léonard; Dias, Luís Filipe; Fonseca, André; Ferreira, TeresaIntensive agricultural and industrial activities are often considered major sources of water contamination. Currently, riparian vegetation (RV) is increasingly being promoted as a solution to balance the potentially adverse effects that agriculture may have on water quality. Nonetheless, existing RV is often overlook in recent modelling efforts, failing to capture the current amount of ecosystem services provide. Here, we used the Soil and Water Assessment Tool ecohydrological model to simulate the influence of ground-true RV on i) nutrient (nitrate and total phosphorus) and sediment exports from agricultural areas and ii) its effect for in-stream concentrations. These results are further compared against a set of hypothetical scenarios of different RV widths and different land-uses. Our results point to a great relevance of existing RV in controlling in-stream concentration of sediments and nutrients where pressure from agriculture is highest, preventing them to surpass limits set in the EU Water Framework Directive. On the other hand, in areas with industry discharges, the role of RV is limited and model results suggest that restoring RV would have limited impacts. We illustrate how existing RV may already provide strong but not acknowledged water quality regulation services, how these services can differ substantially between nearby streams, and that effective strategies to improve water quality using RV must acknowledge existing patterns of vegetation, land use and contamination sources.
- A walk on the wild side: Wild ungulates as potential reservoirs of multi-drug resistant bacteria and genes, including Escherichia coli harbouring CTX-M beta-lactamasesPublication . Torres, Rita Tinoco; Cunha, Mónica V.; Araujo, Débora; Ferreira, Helena; Fonseca, Carlos; Palmeira, Josman DantasExtended-spectrum β-lactamases (ESBL)-producing Enterobacterales have been classified as critical priority pathogens by the World Health Organization (WHO). ESBL are universally distributed and, in 2006, were firstly reported on a wild animal. Understanding the relative contributions of wild animals to ESBL circulation in the environment is urgently needed. In this work, we have conducted a nationwide study in Portugal to investigate the occurrence of bacteria carrying clinically significant antimicrobial resistance genes (ARG), using widely distributed wild ungulates as model species. A total of 151 antimicrobial resistant-Enterobacterales isolates were detected from 181 wild ungulates: 50% (44/88) of isolates from wild boar (Sus scrofa), 40.3% (25/62) from red deer (Cervus elaphus), 41.4% (12/29) from fallow deer (Dama dama) and 100% (2/2) from mouflon (Ovis aries subsp. musimon). Selected isolates showed a diversified resistance profile, with particularly high values corresponding to ampicillin (71.5%) and tetracycline (63.6%). Enterobacterales strains carried blaTEM, tetA, tetB, sul2, sul1 or dfrA1 ARG genes. They also carried blaCTX-M-type genes, which are prevalent in human infections, namely CTX-M-14, CTX-M-15 and CTX-M-98. Strikingly, this is the first report of CTX-M-98 in wildlife. Almost 40% (n = 59) of Enterobacterales were multi-drug resistant. The diversity of plasmids carried by ESBL isolates was remarkable, including IncF, K and P. This study highlights the potential role of wild ungulates as environmental reservoirs of CTX-M ESBL-producing E. coli and in the spill-over of AMR bacteria and their determinants. Our findings suggest that wild ungulates are useful as strategic sentinel species of AMR in terrestrial environments, especially in response to potential sources of anthropogenic pollution, providing early warning of potential risks to human, animal and environmental health.
- Restoration of Triticum aestivum Growth under Salt Stress by Phosphate-Solubilizing Bacterium Isolated from Southern AlgeriaPublication . Belkebla, Nadia; Bessai, Sylia Ait; Melo, Juliana; Caeiro, Maria Filomena; Cruz, Cristina; Nabti, El-hafidSalinity causes significant agricultural losses in many areas in the world. Plant growth promoting bacteria (PGPB) are a promising solution to enhance plant growth and productivity under such stress conditions by different mechanisms, mainly phosphorous solubilization. This study aims to improve wheat seedling growth under salt stress by a halotolerant phosphorous-solubilizing bacterial strain. Soil sample was collected in the south of Algeria (Ghardaia), and bacterial isolation was carried out on nutrient agar (NA) at different NaCl concentrations (300; 600 and 900 mM). The ability of the halotolerant isolates to solubilize inorganic phosphorous at 0; 300; 600 and 900 mM NaCl was determined. The isolate that showed the highest solubilization indexes was selected and identified as Pseudomonas azotoformans. Sterile wheat (Triticum aestivum) seeds were inoculated by this strain and then sown in soil at different NaCl concentrations (0; 100; 200; 300 mM). Different growth parameters were measured after 15 days. The strain showed its highest capacity for phosphorous solubilization (255.152 ± 0.01 µg/mL) at 300 mM NaCl, and for phytate mineralization (0.168 ± 0.002 U/mL) at 100 mM NaCl. The highest amount of soluble phosphorous in the soil was 49.42 ± 0.36 ppm obtained at 100 mM NaCl. Seed germination percentage, shoot and root length and fresh and dry weights were found to be higher in bacterial inoculated seedlings compared to uninoculated ones. According to this study, the use of plant growth promoting bacteria represents an important biotechnological approach to restore phosphorous levels in saline soils and to promote plant growth in salt-affected agricultural land.
- Negative relationship between woody species density and size of urban green spaces in seven European citiesPublication . Alós Ortí, Marta; Casanelles-Abella, Joan; Chiron, François; Deguines, Nicolas; Hallikma, Tiit; Jaksi, Piia; Kwiatkowska, Patrycja K.; Moretti, Marco; Muyshondt, Babette; Niinemets, Ülo; Pinho, Pedro; Pinto, Manuel João; Saar, Peedu; Samson, Roeland; Tryjanowski, Piotr; Van Mensel, Anskje; Laanisto, LauriUrban green spaces (UGSs) are important elements of urban landscapes. Woody vegetation is a key component of UGSs, providing many socio-ecological benefits such as habitat provision and human well-being. Knowing plant diversity and vegetation configuration that underpin urban ecosystem processes and functions is critical to maximize nature contributions to city dwellers. Here, we present a well-replicated multi-city study showing a detailed description of taxonomic and structural diversity of woody vegetation in 225 UGSs distributed across seven European cities along a NE-SW gradient. Our aim was to understand how UGSs attributes, including size and fragmentation, influence woody vegetation features. A total of 418 woody species belonging to 76 families were identified. UGS size displayed weak positive correlations with woody species richness, but a strong negative correlation with woody species density. Alien woody species were abundant in all cities (from 40% of all species recorded in Antwerp to 64% in Lisbon and Zurich). Among the native tree species we found a predominance of Pinus spp. in southern cities and Acer spp. in cooler climates. On average, tree canopies extent was 56% of UGSs. This paper provides insights on the plant diversity and woody vegetation composition in UGSs of different size, climate and urban planning history. Our results encourage and contribute to future urban ecology studies involving different taxa and ecosystem services as well as support effective urban planning and management practices.
- Context‐dependency in carnivore co‐occurrence across a multi‐use conservation landscapePublication . Curveira‐Santos, Gonçalo; Gigliotti, Laura; Sutherland, Chris; Rato, Daniela; Santos-Reis, Margarida; Swanepoel, Lourens H.Carnivore intraguild dynamics depend on a complex interplay of environmental affinities and interspecific interactions. Context-dependency is commonly expected with varying suites of interacting species and environmental conditions but seldom empirically described. In South Africa, decentralized approaches to conservation and the resulting multi-tenure conservation landscapes have markedly altered the environmental stage that shapes the structure of local carnivore assemblages. We explored assemblage-wide patterns of carnivore spatial (residual occupancy probability) and temporal (diel activity overlap) co-occurrence across three adjacent wildlife-oriented management contexts—a provincial protected area, a private ecotourism reserve, and commercial game ranches. We found that carnivores were generally distributed independently across space, but existing spatial dependencies were context-specific. Spatial overlap was most common in the protected area, where species occur at higher relative abundances, and in game ranches, where predator persecution presumably narrows the scope for spatial asymmetries. In the private reserve, spatial co-occurrence patterns were more heterogeneous but did not follow a dominance hierarchy associated with higher apex predator densities. Pair-specific variability suggests that subordinate carnivores may alternate between pre-emptive behavioral strategies and fine-scale co-occurrence with dominant competitors. Consistency in species-pairs diel activity asynchrony suggested that temporal overlap patterns in our study areas mostly depend on species' endogenous clock rather than the local context. Collectively, our research highlights the complexity and context-dependency of guild-level implications of current management and conservation paradigms; specifically, the unheeded potential for interventions to influence the local network of carnivore interactions with unknown population-level and cascading effects.
- Asymmetric globalization and top performers incomePublication . Hellier, JoëlThis paper proposes a new explanation for the rise in top performers’ income based on an asymmetry in globalization, with one country producing globalized non-rivalrous performances (music, films, series, entertainment programmes etc.) whereas other countries produce purely domestic ones. In the country with globalized performances, the globalization dynamics (growing number of countries involved in the global market) entails an increase in the number and incomes of performers and an increase in inequality by the top. The higher the performer’s talent, the higher the globalization-driven increase in income. In countries with purely national performances, the participation in the global economy reduces the number and incomes of performers and lessens inequality by the top. In contrast, when globalization is symmetric (all countries producing globalized performances), there is no change in the number and incomes of performers in all countries compared to autarky. These results are in line with several characteristics observed in activities directly impacted by the cultural supremacy of American and English speaking countries in the global economy: 1) the share of Anglo-Saxon countries in the top 100 richest is substantially higher for actresses, actors, singers and TV show and film producers than for other occupations (CEOs, businessmen etc.), 2) the increase in the share of top incomes is significantly higher in Anglo-Saxon countries, and 3) the increase in inequality is greater in those countries.
- The insurance-growth nexus in Portugal : a multivariate Toda-Yamamoto Granger causality testPublication . López Atienza, Alejandro; Garcia, Maria TeresaThis dissertation provides new insights on the insurance-growth nexus in Portugal, using a multivariate time series analysis over the period 1983-2020. The analysis performed is based around the Granger causality concept, using the Toda and Yamamoto methodology as a consequence of the statistical properties of our time series. The results suggest that there is no causality relation in the Granger sense between economic growth and insurance development in Portugal.
- A primazia pela acomodação da economia brasileiraPublication . Moreira, Marcelo JoséA economia-mundo capitalista está imersa em uma inércia generalizada. Um movimento de lenta acumulação, baixo investimento, limitadas taxas de crescimento, mas com elevado nível de lucro, e que se dá por uma intensa pressão sobre os níveis das desigualdades existentes, combinando reestruturação mundial da geração de riqueza e renda a um padrão de reprodução da força de trabalho ao nível de sua limitada manutenção. Inércia que se verifica, sobretudo, a partir da crise financeiro-produtiva da primeira década dos anos de 2000. O Brasil não está alheio a essa inércia e aos seus desdobramentos. Este artigo pretende, a partir de uma reflexão conceitual, discutir os elementos que caracterizam o que denomino de estrutura da acomodação da economia brasileira.
- Nutrient-limited subarctic caves harbour more diverse and complex bacterial communities than their surface soilPublication . Sofia Reboleira, Ana; Bodawatta, Kasun H.; Ravn, Nynne M. R.; Lauritzen, Stein-Erik; Skoglund, Rannveig Øvrevik; Poulsen, Michael; Michelsen, Anders; Jønsson, Knud AndreasBackground: Subarctic regions are particularly vulnerable to climate change, yet little is known about nutrient availability and biodiversity of their cave ecosystems. Such knowledge is crucial for predicting the vulnerability of these ecosystems to consequences of climate change. Thus, to improve our understanding of life in these habitats, we characterized environmental variables, as well as bacterial and invertebrate communities of six subarctic caves in Northern Norway. Results: Only a minuscule diversity of surface-adapted invertebrates were found in these caves. However, the bacte‑ rial communities in caves were compositionally diferent, more diverse and more complex than the nutrient-richer surface soil. Cave soil microbiomes were less variable between caves than between surface communities in the same area, suggesting that the stable cave environments with tougher conditions drive the uniform microbial communi‑ ties. We also observed only a small proportion of cave bacterial genera originating from the surface, indicating unique cave-adapted microbial communities. Increased diversity within caves may stem from higher niche specialization and levels of interdependencies for nutrient cycling among bacterial taxa in these oligotrophic environments. Conclusions: Taken together this suggest that environmental changes, e.g., faster melting of snow as a result of global warming that could alter nutrient infux, can have a detrimental impact on interactions and dependencies of these complex communities. This comparative exploration of cave and surface microbiomes also lays the founda‑ tion to further investigate the long-term environmental variables that shape the biodiversity of these vulnerable ecosystems.
- Alexandre Luís da Cunha. Um Professor Liberal no Mundo Atlântico (primeira metade do século XIX)Publication . Silva, Carlos Manique DaEste artigo procura narrar a história de vida de uma personalidade-Alexandre Luís da Cunha (1803-1852)-que nasceu, viveu e faleceu no Funchal (ilha da Madeira, Por-tugal), mas que, por razões várias, nomeadamente, profissionais e políticas (por duas vezes se encontrou na situação de exilado liberal), circulou no mundo atlântico. A sua atividade profissional foi muito intensa e diversificada, embora se tivesse identificado, sobretudo, com a docência. No texto procura-se elucidar os aspetos mais marcantes da vida pessoal e pro-fissional de Alexandre Luís da Cunha, enfatizando a sua condição de liberal, manifestada na luta pela liberdade de expressão e pelos valores da tolerância.