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- Modelling the response of urban lichens to broad-scale changes in air pollution and climatePublication . Rocha, Bernardo; Matos, Paula; Giordani, Paolo; Piret, Lõhmus; Branquinho, Cristina; Casanelles-Abella, Joan; Aleixo, Cristiana; Deguines, Nicolas; Hallikma, Tiit; Laanisto, Lauri; Moretti, Marco; Alós Ortí, Marta; Samson, Roeland; Tryjanowski, Piotr; Pinho, PedroTo create more resilient cities, it is important that we understand the effects of the global change drivers in cities. Biodiversity-based ecological indicators (EIs) can be used for this, as biodiversity is the basis of ecosystem structure, composition, and function. In previous studies, lichens have been used as EIs to monitor the effects of global change drivers in an urban context, but only in single-city studies. Thus, we currently do not understand how lichens are affected by drivers that work on a broader scale. Therefore, our aim was to quantify the variance in lichen biodiversity-based metrics (taxonomic and trait-based) that can be explained by environmental drivers working on a broad spatial scale, in an urban context where local drivers are superimposed. To this end, we performed an unprecedented effort to sample epiphytic lichens in 219 green spaces across a continental gradient from Portugal to Estonia. Twenty-six broad-scale drivers were retrieved, including air pollution and bio-climatic variables, and their dimensionality reduced by means of a principal component analysis (PCA). Thirty-eight lichen metrics were then modelled against the scores of the first two axes of each PCA, and their variance partitioned into pollution and climate components. For the first time, we determined that 15% of the metric variance was explained by broad-scale drivers, with broad-scale air pollution showing more importance than climate across the majority of metrics. Taxonomic metrics were better explained by air pollution, as expected, while climate did not surpass air pollution in any of the trait-based metric groups. Consequently, 85% of the metric variance was shown to occur at the local scale. This suggests that further work is necessary to decipher the effects of climate change. Furthermore, although drivers working within cities are prevailing, both spatial scales must be considered simultaneously if we are to use lichens as EIs in cities at continental to global scales.
- Microclimate simulation and lichen-based validation analyzing street trees' impact on atmospheric pollutant dispersion at the urban canyon scalePublication . Girotti, Carolina; Matos, Paula; Shimomura, Alessandra R. Prata; Kurokawa, Fernando Akira; Correia, Ezequiel; Lopes, AntónioThis study investigates the impact of street trees on air pollutant concentrations, specifically NO₂ and PM10, in urban environments using computational fluid dynamics (CFD) simulations with ENVI-met software. The study explores how different levels of tree cover influence the dispersion of atmospheric pollutants, focusing on three scenarios: current tree cover, complete removal of street trees, and a 50 % reduction in tree cover. Avenida da Liberdade in Lisbon, known for its high tree density, serves as the study site. To ensure the accuracy of the simulations, the method was validated using air quality data from a local monitoring station, supplemented by an analysis of lichen diversity on 80 trees, a common biomonitor for pollution. The results indicate that both NO₂ and PM10 concentrations are higher under tree canopies, with the greatest increase observed on the windward side of the avenue. Specifically, PM10 levels rose by up to 2.97 %, and NO₂ by up to 25.84 % in the scenario with the highest tree cover. Moreover, the study highlights that street trees have a more significant effect on NO₂ concentrations compared to PM10. The findings suggest that, in this specific case—where there is a high density of trees and low wind speed— reducing tree coverage and improve permeability to the wind, could improve pollution dispersion. This study provides key findings into the complex role of urban trees in air quality and offers a foundation for future research into the modelling of additional pollutants, such as PM2.5 and ozone, to gain a more comprehensive understanding of their impacts on urban air quality.
- Incorporating biotic interactions to better model current and future vegetation of the maritime AntarcticPublication . Rocha, Bernardo; Pinho, Pedro; Giordani, Paolo; Concostrina-Zubiri, Laura; Vieira, Gonçalo; Pina, Pedro; Branquinho, Cristina; Matos, PaulaMaritime Antarctica’s harsh abiotic conditions forged simple terrestrial ecosystems, mostly constituted of bryophytes, lichens, and vascular plants. Though biotic interactions are, together with abiotic factors, thought to help shape this ecosystem, influencing species’ distribution and, indirectly, mediating their response to climate, the importance of these interactions is still fairly unknown. We modeled current and future abundance patterns of bryophytes, lichens, and vascular plants, accounting for biotic interactions and abiotic drivers, along a climatic gradient in maritime Antarctica. The influence of regional climate and other drivers was modeled using structural equation models, with and without biotic interactions. Models with biotic interactions performed better; the one offering higher ecological support was used to estimate current and future spatial distributions of vegetation. Results suggest that plants are confined to lower elevations, negatively impacting bryophytes and lichens, whereas at higher elevations both climate and other drivers influence bryophytes and lichens. Our findings strongly support the use of biotic interactions to predict the spatial distribution of Antarctic vegetation.
- Microscale is key to model current and future Maritime Antarctic vegetationPublication . Matos, Paula; Rocha, Bernardo; Pinho, Pedro; Miranda, Vasco; Pina, Pedro; Goyanes, Gabriel; Vieira, GonçaloDespite being one of the most pristine regions in the world, Antarctica is currently also one of the most vulnerable to climate change. Antarctic vegetation comprises mostly lichens and bryophytes, complemented in some milder regions of Maritime Antarctica by two vascular plant species. Shifts in the spatial patterns of these three main vegetation groups have already been observed in response to climate change, highlighting the urgent need for the development of comprehensive large-scale ecological models of the effects of climate change. Besides climate, Antarctic terrestrial vegetation is also strongly influenced by non-climatic microscale conditions related to abiotic and biotic factors. Nevertheless, the quantification of their importance in determining vegetation patterns remains unclear. The objective of this work was to quantify the importance of abiotic and biotic microscale conditions in determining the spatial cover patterns of the major functional types, lichens, vascular plants and bryophytes, explicitly determining the likely confinement of each functional type to the microscale conditions, i.e., their ecological niche. Microscale explained >60 % of the spatial variation of lichens and bryophytes and 30 % of vascular plants, with the niche analysis suggesting that each of the three functional types may be likely confined to specific microscale conditions in the studied gradient. Models indicate that the main microscale ecological filters are abiotic but show the potential benefits of including biotic variables and point to the need for further clarification of vegetation biotic interactions' role in these ecosystems. Altogether, these results point to the need for the inclusion of microscale drivers in ecological models to track and forecast climate change effects, as they are crucial to explain present vegetation patterns in response to climate, and for the interpretation of ecological model results under a climate change perspective.
- Functional diversity in marine fish assemblagesPublication . Henriques, Sofia; Dolbeth, Marina; Matos, Paula; Pecuchet, Laurene; Bernardo, Cristiane Palaretti; Weigel, Benjamin; McLean, Matthew; Hidalgo, Manuel; Tzanatos, Evangelos; Vasconcelos, Rita P.In the last decades, the rising interest in trait-based ecology is closely related to a growing demand for knowledge on ecosystems’ functioning and on mechanisms generating ecological patterns and processes, and with the urgency for approaches that allow to predict the consequences of climate change and anthropogenic impacts (McGill et al., 2006; De Bello et al., 2021a,b). This fundamental knowledge is difficult to obtain when considering specific species (i.e., taxonomic-based ecology), therefore ecologists are increasingly using functional diversity approaches (i.e., trait-based ecology), with the added advantage of allowing the comparison across different ecosystems and biogeographical regions, which due to biogeographical reasons support different species compositions (e.g., Henriques et al., 2017a,b). Functional diversity (FD) refers to the distribution and range of what species do (as determined by their functional traits) in a given ecosystem, influencing how the ecosystem operates or functions (e.g., stability, dynamics, productivity; Tilman, 2001; Petchey and Gaston, 2006). Currently, the most accepted definition of the trait was proposed by Violle and colleagues in which a trait is defined as “any morphological, physiological or phenological feature measurable at the individual level, from the cell to the whole organism” (Violle et al., 2007). For a trait to be considered a functional trait, it needs to influence organismal performance (fitness), meaning its growth, reproduction, and/or survival (McGill et al., 2006; Violle et al., 2007). Additionally, traits can also be related to the effect of organisms on ecosystem properties, or on the other hand, to how they respond to a disturbance or environmental change (Hooper et al., 2005). In this way, traits can be further divided into the following: (1) effect traits, those that significantly affect another trophic level (e.g., predator-prey interactions) and/or an ecosystem process (e.g., nutrient cycling, primary productivity), regardless of whether they affect or not the organismal performance; (2) response traits, those that allow organisms to survive, grow, and reproduce under different disturbances and/or environmental conditions (biotic and abiotic factors; Lavorel and Garnier, 2002).
- Rice fields play a complementary role within the landscape mosaic supporting structurally and functionally distinct waterbird communitiesPublication . Paulino, João; Granadeiro, José Pedro; Matos, Paula; Catry, TeresaThis study aims to understand how the structure and functions of waterbird communities in rice fields compare to those in other habitats within an agricultural landscape encompassing five habitats: saltpans, lakes, intertidal areas, pastures and rice fields. Over 2 years, waterbird counts were conducted every 15 days in these habitats. Non-metric multidimensional scaling was used to compare the composition and functional structure of the waterbird communities. Differences in both metrics were found among habitats throughout the year. These appear to be driven by spatial (presence of permanent water cover) and temporal gradients (yearly seasonality). Rice fields occupy a central position within the gradients. The composition and functional structure of waterbird communities in rice fields undergo significant changes throughout the year associated with the annual rice production cycle. Other habitats maintain more consistent communities, reflecting their more stable environmental conditions. Rice fields play a complementary role to other habitats in the landscape, likely acting as a buffer, partially mitigating the loss of some waterbird species amid the global decline of natural wetlands.
- Ant functional structure and diversity changes along a post-grazing succession in Mediterranean oak woodlandsPublication . Frasconi Wendt, Clara; Nunes, Alice; Köbel, Melanie; Verble, Robin; Matos, Paula; Boieiro, Mário; Branquinho, CristinaGrazing exclusion may be used to promote the recovery of disturbed ecosystems. A promising way for the evaluation of its effectiveness is through the monitoring of key biological groups, particularly those more responsive to disturbance and playing key roles in ecosystem functioning. Ants have been used as ecological indicators as they are abundant, diverse and sensitive to environmental changes. Here, we aimed to evaluate changes in ant taxonomic and functional structure and diversity, using functional groups, along a post-grazing succession in a Mediterranean oak woodland and to understand which environmental variables drive them. The post-grazing succession comprised a chronosequence of grazing excluded sites for 8, 12 and 18 years and a grazed control site. We found that ant species richness, functional structure and diversity increased with years since grazing exclusion: Generalist/Opportunist and the Hot Climate specialists increased in the 18 years grazing excluded site, while the Cryptic Species group increased in the 12 years grazing excluded site. Yet, their responses were not linear over time. Time since grazing exclusion and vegetation structure explained differences in ant taxonomic and functional structure and diversity. The Invasive/Exotic group dominated in all sites, except in the longest excluded site, where it occurred in the lowest proportion. The invasive Argentine ant dominated the grazed site, where it may have led to ant taxonomic and functional homogenization. Our results suggest that the time and changes in habitat structure may favour the recovery of ant biodiversity, although the presence of the invasive Argentine ant species may have slowed it down.