Biology subjects

Marchante, E.

Publications and source records attributed to Marchante, E..

3 recordsLinked to original sources

bioRxiv2025

Distribution patterns of invasive alien plant species in mainland Portugal

Understanding the distribution and diversity of invasive alien species is increasingly vital to meet legal requirements and guide effective management. Portugal currently hosts a large number of invasive alien plant species, with significant environmental and socio-economic impacts. However, the distribution of most of these species in the territory and the factors driving their spread and diversity remain largely unexplored. To address this, we present the first atlas of invasive plants in mainland Portugal. A total of 96 terrestrial and aquatic invasive plants are represented, encompassing all species listed under Portuguese national legislation and the European Unions list of invasive species of concern. Occurrence data were collected from a broad array of sources, including national and international biodiversity observation databases, citizen science data, literature, and data collections owned by managers and researchers, totaling approximately 85,000 records (mean = 879 {+/-} 1,757 per species). Each species was characterized based on multiple distributional parameters, and a k-means analysis was used to group species with similar distribution patterns. The richness of invasive plants was mapped at the municipality level, and the drivers of their spatial variation were investigated using a comprehensive set of 30 variables representing multiple environmental and human factors. Results show that invasive plants occur in all mainland Portuguese municipalities, but with high variability. Four main patterns of distribution were identified: species that are primarily located along the coast (e.g., Acacia saligna), and a gradient of species with narrow (e.g., Reynoutria japonica), moderate (e.g., Ipomoea indica), and wide distribution ranges (e.g., Cortaderia selloana). Species richness was significantly higher in coastal and larger municipalities, particularly those closer to major urban centers and with a higher density of power lines. Our results provide the first comprehensive assessment of the distribution of invasive alien plants in mainland Portugal, establishing a much-needed baseline for future invasion prevention and management efforts.

ecology↗

bioRxiv2023

Recent land use and land cover pressures on Iberian peatlands

Iberian peatlands have been severely affected by land use and land cover (LULC) changes. Despite these pressures, some peatlands persist in the region, although their susceptibility to LULC change remains poorly understood. This study presents the most detailed and extensive distribution data for Iberian peatlands to date and analyzes the dynamics and drivers of LULC in Iberian peatlands and their surrounding areas. We compiled peatland records from various sources and used Corine Land Cover Change layers to determine LULC shifts for 1990, 2000, 2006, 2012, and 2018. Environmental and socioeconomic variables were used to create Boosted Regression Tree models explaining spatial variations in the mean percentage of changed area. Analysis of 270 peatland locations in the Iberian Peninsula revealed that forests and seminatural areas constituted over 80% of the peatlands surroundings. Agricultural areas expanded the most, except between 2006 and 2012 when the artificial areas showed more gains. While most areas experienced an average change of 0%-9.51% of the total area, between 1990 and 2018, lowland peatlands (littoral and sublittoral) suffered more intense changes (9.51% to 38.43%). Our models showed that only elevation and agricultural area density were relevant predictors of spatial distribution changes. Upland Iberian peatlands showed lower susceptibility to LULC changes, while lowland peatlands underwent remarkable transformations. This study substantially expands previous knowledge about the distribution and conservation needs of these ecosystems in the Iberian Peninsula, especially those in littoral and sublittoral lowlands.

ecology↗

bioRxiv2021

Tripartite networks show that keystone species can multitask

Keystone species are disproportionately important for ecosystem functioning (1,2). However, while all species engage in multiple interaction types with other species, the importance of keystone species is often defined based on a single dimension of their Eltonian niche (3), that is, one type of interaction (e.g., keystone predator). Therefore, it remains unclear whether the importance of keystone species is unidimensional or if it extends across interaction types. We conducted a meta-analysis of tripartite interaction networks to examine whether species importance in one dimension of their niche is mirrored in other niche dimensions, and whether this is associated with interaction outcome, intimacy, or species richness. We show that keystone species importance is positively associated across multiple ecological niche dimensions, independently of species abundance, and find no evidence that multidimensionality of keystone species is influenced by the explanatory variables. We propose that the role of keystone species extends across multiple ecological niche dimensions, with important implications for ecosystem resilience and conservation. Significance StatementKeystone species are often identified by focusing on a single type of interaction (e.g., predation, pollination, herbivory) which contrasts with the multiple roles that species play in biological communities. We conducted a meta-analysis of 18 tripartite interaction networks to explore if keystonness is correlated across the multiple dimensions of species Eltonian niches. Our results suggest that species importance tends to span across multiple interaction types, independently from abundance, which can be key to understand community resilience and collapse in face of multiple threats.

ecology↗