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- Diversification of Aeonium Species Across Macaronesian Archipelagos: Correlations Between Genome-Size Variation and Their Conservation StatusPublication . Brilhante, Miguel; Roxo, Guilherme; Catarino, Sílvia; Dos Santos, Patrícia; Reyes-Betancort, J. Alfredo; Caujapé-Castells, Juli; Sequeira, Miguel Menezes; Talhinhas, Pedro; Romeiras, Maria M.The rich endemic flora of the Macaronesian Islands places these oceanic archipelagos among the top biodiversity hotspots worldwide. The radiations that have determined the evolution of many of these insular lineages resulted in a wealth of endemic species, many of which occur in a wide range of ecological niches, but show small distribution areas in each of them. Aeonium (Crassulaceae) is the most speciose lineage in the Canary Islands (ca. 40 taxa), and as such can be considered a good model system to understand the diversification dynamics of oceanic endemic floras. The present study aims to assess the genome size variation within Aeonium distribution, i.e., the Macaronesian archipelagos of Madeira, Canaries and Cabo Verde, and analyse it together with information on distribution (i.e., geography and conservation status), taxonomy (i.e., sections), morphological traits (i.e., growth-form), geological data (i.e., island’s geological age), and environmental variables (i.e., altitude, annual mean temperature, and precipitation). Based on extensive fieldwork, a cytogeographic screening of 24 Aeonium species was performed. The conservation status of these species was assessed based on IUCN criteria. 61% of the taxa were found to be threatened (4% Endangered and 57% Vulnerable). For the first time, the genome size of a comprehensive sample of Aeonium across the Macaronesian archipelagos was estimated, and considerable differences in Cx-values were found, ranging from0.984 pg (A. dodrantale) to 2.768 pg (A. gorgoneum). An overall positive correlation between genome size and conservation status was found, with the more endangered species having the larger genomes on average. However, only slight relationships were found between genome size, morphological traits, and environmental variables. These results underscore the importance of characterizing the cytogenomic diversity and conservation status of endemic plants found in Macaronesian Islands, providing, therefore, new data to establish conservation priorities.
- From historical research to urban ecology: A new perspective on the evolution of the landscape art in LisbonPublication . Cunha, Ana Raquel; Romeiras, Maria Manuel; Brilhante, Miguel; Rego, Francisco Castro; Soares, Ana LuísaLisbon has unique characteristics and hosts a higher average biodiversity than other European cities. Its Mediterranean climate allows the coexistence of different tree species, and the contact with other geographies and cultures resulting from the Portuguese discoveries contributed to the botanical richness of species from around the world. This study focused on the 1929 and 2014 tree inventories, which allowed a comparative analysis of the tree collections in Lisbon’s gardens, revealing similarities and singularities and tracing their evolution over time. Tree abundance and species richness increased between the two dates, as did the number of green areas in Lisbon. This tendency is explained by the introduction of Landscape Architecture in Portugal in the mid-20th century when landscape architects first became part of the Lisbon municipality; the Repartição de Arborização e Jardinagem was then created, launching an innovative period for the town’s green spaces, where aesthetics were articulated with contemporary landscape concepts such as ecology. The present study allowed us to assess the evolution of almost a century of plantations, providing tools to prepare the future of Lisbon’s urban ecology. Moreover, it significantly contributes to the understanding of Lisbon’s historical gardens and parks as a valuable natural and cultural heritage.