From the flowers to the cells: a trait-based and cytogenomic study of Macaronesian Aeonium genus (Crassulaceae)

Tese de mestrado, Biologia dos Recursos Vegetais, Universidade de Lisboa, Faculdade de Ciências, 2019Macaronesian region comprises five archipelagos (i.e., Azores, Madeira, Selvagens, Canary Islands and Cabo Verde) in the Northeastern Atlantic Ocean. Volcanic in nature, all archipelagos reach high altitudes even in relatively small areas and harbor an extremely rich endemic flora, including notable examples of plant radiation, such as the genus Aeonium (ca. 41 taxa), Sonchus (ca. 31 taxa) and Echium (ca. 27 taxa). Considered a biodiversity hotspot, Macaronesia is recognized as a model for studying the evolutionary processes involved in flora diversification. Aeonium genus (Crassulaceae) includes about 41 taxa and is considered the most speciose radiation of Macaronesia, occupying many contrasting habitat types in the Canary Islands, Madeira and Cabo Verde. The great species richness and the wide range of characters observed in Aeonium species make it a model of study par excellence. This dissertation aimed to study the reproductive traits and cytogenomic variation patterns of Aeonium genus in order to understand the characters that influence the distribution of the most speciose radiation of Macaronesian Region. For these purposes, a holistic approach was used that integrates different methods in the areas of reproductive biology (Chapter 2), cytogenomics (Chapter 3) and conservation biology (Chapter 4), based on extensive fieldwork on the islands of the Canary Islands. The reproductive trait-based results (Chapter 2) showed that inflorescence height was positively correlated to flower number and geographic range size. This suggested that species that invest in taller inflorescences and more reproductive units have wider distributions and a more generalist behavior. According to the cytogenomic results (Chapter 3), Aeonium species tend to have small genomes, being subshrubs the large-genomed ones. Comparative analysis across the genus revealed a positive correlation between 2C-values and conservation status, owning endangered species, on average, large genomes. Finally, in a conservation approach (Chapter 4), most of Aeonium taxa occur in Tenerife in Teno Rural Park and Anaga Rural Parks, being there their hotspot of biodiversity. The representation of Aeonium endemics in the network of the Protected Areas is relatively high once a large area (40%) of Canary Islands is classified as protected. Thus, by integrating the knowledge of the various approaches applied in the three chapters (2 – 4) of this dissertation, it was possible to contribute with new data to explain the distribution of Aeonium and detect hotspots areas of species diversity, based on inflorescence height, genome size and abiotic factors. Some species have their limited range of occurrence, among other external factors (e.g., anthropogenic action and invasive species), by the reduced inflorescence height. On the other hand, species with a larger genome do not respond to this trend and have also limited dispersal ranges. However, further morphological, cytogenomic analyzes and more fieldwork in all Macaronesian Islands to inventory all Aeonium species will reinforce the results and identify the main factors leading to the large diversification of largest plant radiation of Macaronesia, contributing to the preservation of the unique biodiversity existing in these island ecosystems

Juromenha: a Chave do Guadiana - O lugar, a fortificação e o futuro

A Arquitectura Militar enquanto disciplina integrante da História da Arte é um fenómeno recente. É uma área na qual, em Portugal, ainda há muito por descobrir e conhecer. A presente investigação tem como objectivo estudar a Fortaleza de Juromenha, situada no Alentejo, monumento militar do século XVII, dos pontos de vista histórico e artístico, desde os seus antecedentes até aos dias de hoje, focando-se particularmente na fortificação moderna abaluartada, na história da sua construção, e no papel que desempenhou ao longo da Guerra da Restauração. A falta de uma monografia sobre a Fortaleza de Juromenha, uma das fortificações de maior destaque na defesa da fronteira do Alentejo durante a Guerra da Restauração, considerada a Chave do Guadiana, motivou a escolha desta fortificação como objecto de estudo para a presente dissertação. Esse é o principal objectivo desta dissertação, escrever uma monografia sobre a Fortaleza de Juromenha.Military Architecture as History of Art’s discipline is a recent phenomenon. In Portugal, it is an area were there is still much to investigate and to know. The objective of this work is to study the Juromenha’s fortress, in Alentejo, military monument from the XVII century, from historical and artistic points of view, since its background to present days, focusing particulary on the modern fortification, the history of its construction, and the role that it played during the Restoration War. The lack of a monogrphy about the Juromenha’s fortress, one of the most important fortifications in the defense of the Alentejo’s border during the Restoration War, considered to be the Guadiana’s Key, motivated the choice of this fortification as case study for this dissertation. This is the main objective of this dissertation, to write a monography about Juromenha’s fortress

Codificador JPEG baseado em FPGA

O presente trabalho consiste na implementação em hardware de unidades funcionais dedicadas e optimizadas, para a realização das operações de codificação e descodificação, definidas na norma de codificação com perda Joint Photographic Experts Group (JPEG), ITU-T T.81 ISO/IEC 10918-1. Realiza-se um estudo sobre esta norma de forma a caracterizar os seus principais blocos funcionais. A finalidade deste estudo foca-se na pesquisa e na proposta de optimizações, de forma a minimizar o hardware necessário para a realização de cada bloco, de modo a que o sistema realizado obtenha taxas de compressão elevadas, minimizando a distorção obtida. A redução de hardware de cada sistema, codificador e descodificador, é conseguida à custa da manipulação das equações dos blocos Forward Discrete Cosine Transform (FDCT) e Quantificação (Q) e dos blocos Forward Discrete Cosine Transform (IDCT) e Quantificação Inversa (IQ). Com as conclusões retiradas do estudo e através da análise de estruturas conhecidas, descreveu-se cada bloco em Very-High-Speed Integrated Circuits (VHSIC) Hardware Description Language (VHDL) e fez-se a sua síntese em Field Programmable Gate Array (FPGA). Cada sistema implementado recorre à execução de cada bloco em paralelo de forma a optimizar a codificação/descodificação. Assim, para o sistema codificador, será realizada a operação da FDCT e Quantificação sobre duas matrizes diferentes e em simultâneo. O mesmo sucede para o sistema descodificador, composto pelos blocos Quantificação Inversa e IDCT. A validação de cada bloco sintetizado é executada com recurso a vectores de teste obtidos através do estudo efectuado. Após a integração de cada bloco, verificou-se que, para imagens greyscale de referência com resolução de 256 linhas por 256 colunas, é necessário 820,5 μs para a codificação de uma imagem e 830,5 μs para a descodificação da mesma. Considerando uma frequência de trabalho de 100 MHz, processam-se aproximadamente 1200 imagens por segundo

Genome size variation within Crithmum maritimum: Clues on the colonization of insular environments

Angiosperms present an astonishing diversity of genome sizes that can vary intra- or interspecifically. The remarkable new cytogenomic data shed some light on our understanding of evolution, but few studies were performed with insular and mainland populations to test possible correlations with dispersal, speciation, and adaptations to insular environments. Here, patterns of cytogenomic diversity were assessed among geographic samples (ca. 114) of Crithmum maritimum (Apiaceae), collected across the Azores and Madeira archipelagos, as well as in adjacent continental areas of Portugal. Using flow cytometry, the results indicated a significant intraspecific genome size variation, spanning from reduced sizes in the insular populations to larger ones in the mainland populations. Moreover, there was a tendency for an increase in genome size along the mainland populations, associated with lower temperatures, higher precipitation, and lower precipitation seasonality. However, this gradient might be the result of historic phylogeographical events associated with previous dispersal and extinction of local populations. Overall, our findings provided evidence that smaller genome sizes might play a critical role in the colonization of islands, corroborating other studies that argue that organisms with smaller genomes use fewer resources, having a selective advantage under insular environments. Although further studies are needed to improve our understanding of the mechanisms underlying genome size evolution on islands, conservation strategies must be promoted to protect the rich cytogenomic diversity found among C. maritimum populations, which occur in coastal areas that are particularly threatened by human activity, pollution, invasive species, and climate changes.info:eu-repo/semantics/publishedVersio

Diversification of Aeonium Species Across Macaronesian Archipelagos: Correlations Between Genome-Size Variation and Their Conservation Status

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.info:eu-repo/semantics/publishedVersio

Natural and Historical Heritage of the Lisbon Botanical Gardens: An Integrative Approach with Tree Collections

Botanical gardens have long contributed to plant science and have played a leading role in ex situ conservation, namely of threatened tree species. Focusing on the three botanical gardens of Lisbon (i.e., Botanical Garden of Ajuda—JBA, Lisbon Botanical Garden—JBL, and Tropical Botanical Garden—JBT), this study aims to reveal their natural heritage and to understand the historical motivations for their creation. Our results showed that these gardens contain a total of 2551 tree specimens, corresponding to 462 taxa, within 80 plant families. Of these, 85 taxa are found in the three gardens, and more than half of the taxa are hosted in JBL (334 taxa), whereas 230 and 201 taxa were recorded in JBT and JBA, respectively. The motivations for the creation of each garden are reflected in the different geographic origins of the trees they host in their living collections. The Palearctic species are dominant in JBA and JBL, and Tropical trees prevail in JBT. With more than 250 years of history, these gardens hold an invaluable natural and historical heritage, with their living collections providing valuable sources of information for the conservation of threatened plant species, at local and global scalesinfo:eu-repo/semantics/publishedVersio

Plant growth forms dictate adaptations to the local climate

Adaptive radiation is a significant driver of biodiversity. Primarily studied in animal systems, mechanisms that trigger adaptive radiations remain poorly understood in plants. A frequently claimed indicator of adaptive radiation in plants is growth form diversity when tied to the occupation of different habitats. However, it remains obscure whether morphological adaptations manifest as growth form diversity per se or as its constituent traits. We use the classic Aeonium radiation from the Canary Islands to ask whether adaptation across climatic space is structured by growth form evolution. Using morphological sampling with site-associated climate in a phylogenetic context, we find that growth forms dictate adaptations to the local environment. Furthermore, we demonstrate that the response of specific traits to analogous environments is antagonistic when growth forms are different. This finding suggests for the first time that growth forms represent particular ecological functions, allowing the co-occurrence of closely related species, being a product of divergent selection during evolution in sympatry.info:eu-repo/semantics/publishedVersio

Tackling Food Insecurity in Cabo Verde Islands: The Nutritional, Agricultural and Environmental Values of the Legume Species

Legume species are important food sources to reduce hunger and deal with malnutrition; they also play a crucial role in sustainable agriculture in the tropical dry islands of Cabo Verde. To improve the knowledge of the heritage of plant genetic resources in this Middle Income Country, this study had three main goals: (i) to provide a checklist of food legumes; (ii) to investigate which species are traded in local markets and, based on field surveys, to compare species for their chemical, phenolic, antioxidant, and nutritional composition; and (iii) to discuss the agronomic value and contribution to food security in this archipelago. Our results revealed that 15 species are used as food and 5 of them are locally traded (Cajanus cajan, Lablab purpureus, Phaseolus lunatus, Phaseolus vulgaris, and Vigna unguiculata). The role of these species as sources of important minerals, antioxidants, and nutritional components for food security is highlighted, and the native ones (Lablab purpureus and Vigna unguiculata) stand-out as particularly well-adapted to the climate of these islands, which are already experiencing the adverse effects of climate change. We conclude that the sustainable use of these genetic resources can contribute to the reduction of hunger and poverty, thus meeting some challenges of the Sustainable Development Goals.info:eu-repo/semantics/publishedVersio

Diversity of Useful Plants in Cabo Verde Islands: A Biogeographic and Conservation Perspective

Cabo Verde’s biodiversity is threatened by activities that meet human needs. To counteract this, an integration of scientific and indigenous knowledge is required, but no comprehensive list of the useful local plants is available. Thus, in this work, we assess (1) their diversity and phytogeography; (2) the role of geophysical, historical, and socio-economic factors on species distribution and uses; and (3) potentially relevant species for sustainable development. Data were obtained from flora, scientific publications, historical documents, herbarium specimens and field work. Many species were introduced since the 15th century to support settlement and commercial interests. We identified 518 useful taxa, of which 145 are native, 38 endemic and 44 endangered. The number of useful taxa is correlated with altitude and agricultural area, as well as with rural population indicators, but not with total population or socio-economic indicators such as gross domestic product. Native taxa are mostly used for fuelwood, forage and utilitarian purposes. Agrobiodiversity and traditional practices seem crucial to cope with recurrent droughts and ensure food security. Most of the introduced species do not present conservation problems, contrasting with the overuse of some native taxa. The safeguarding of native populations will ensure the sustainable exploitation of these resources and benefit the local economy.info:eu-repo/semantics/publishedVersio

Inter- and intra-island speciation and their morphological and ecological correlates in Aeonium (Crassulaceae), a species-rich Macaronesian radiation

Background and Aims The most species-rich and ecologically diverse plant radiation on the Canary Islands is the Aeonium alliance (Crassulaceae). In island radiations like this, speciation can take place either within islands or following dispersal between islands. Aiming at quantifying intra- and inter-island speciation events in the evolution of Aeonium, and exploring their consequences, we hypothesized that (1) intra-island diversification resulted in stronger ecological divergence of sister lineages, and that (2) taxa on islands with a longer history of habitation by Aeonium show stronger ecological differentiation and produce fewer natural hybrids. Methods We studied the biogeographical and ecological setting of diversification processes in Aeonium with a fully sampled and dated phylogeny inferred using a ddRADseq approach. Ancestral areas and biogeographical events were reconstructed in BioGeoBEARS. Eleven morphological characters and three habitat characteristics were taken into account to quantify the morphological and ecological divergence between sister lineages. A co-occurrence matrix of all Aeonium taxa is presented to assess the spatial separation of taxa on each island. Key Results We found intra- and inter-island diversification events in almost equal numbers. In lineages that diversified within single islands, morphological and ecological divergence was more pronounced than in lineages derived from inter-island diversification, but only the difference in morphological divergence was significant. Those islands with the longest history of habitation by Aeonium had the lowest percentages of co-occurring and hybridizing taxon pairs compared with islands where Aeonium arrived later. Conclusions Our findings illustrate the importance of both inter- and intra-island speciation, the latter of which is potentially sympatric speciation. Speciation on the same island entailed significantly higher levels of morphological divergence compared with inter-island speciation, but ecological divergence was not significantly different. Longer periods of shared island habitation resulted in the evolution of a higher degree of spatial separation and stronger reproductive barriers.info:eu-repo/semantics/publishedVersio