Browsing by Author "Romeiras, Maria M."
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- Agro-Economic Transitions in Guinea-Bissau (West Africa): Historical Trends and Current InsightsPublication . Havik, Philip; Monteiro, Filipa; Catarino, Silvia; Correia, A.; Catarino, Luís; Romeiras, Maria M.The present study provides a critical analysis of the introduction of exotic food crop species and their impact on agricultural transformations in Guinea-Bissau, based on survey data and a review of the literature from the 1800s to the present. It applies a multidisciplinary analysis to map historical and contemporary agrarian knowledge in Guinea-Bissau, presenting the first list of exotic cultivated species introduced in the country. Our results show that many introduced crops have gained widespread acceptance among local producers, with 63 exotic cultivated species native to America and Asia. The most representative families are Fabaceae, Solanaceae, and Anacardiaceae, including the country’s main former and current cash crops. First driven by peanuts in colonial times and by cashew after independence from 1980s onwards, Guinea-Bissau rapidly became one of Africa’s major exporters. The current cashew monoculture—like peanuts before it—relies almost exclusively on smallholder agriculture, raising concerns with regard to biodiversity, sustainability, and food security. The paper analyses historical trends in agro-economic transformations taking into account policies, programs, performance, and scientific research. Despite the existence of a long-standing single crop economy, further research is needed in this largely understudied country to assess the impact of long-term agrarian change.
- An expanded molecular phylogeny of Plumbaginaceae, with emphasis on Limonium (sea lavenders): Taxonomic implications and biogeographic considerationsPublication . Koutroumpa, Konstantina; Theodoridis, Spyros; Warren, Ben H.; Jiménez, Ares; Celep, Ferhat; Doğan, Musa; Romeiras, Maria M.; Santos‐Guerra, Arnoldo; Fernández‐Palacios, Jóse María; Caujapé‐Castells, Juli; Moura, Mónica; Menezes de Sequeira, Miguel; Conti, ElenaPlumbaginaceae is characterized by a history of multiple taxonomic rearrangements and lacks a broad molecular phylogenetic framework. Limonium is the most species-rich genus of the family with ca. 600 species and cosmopolitan distribution. Its center of diversity is the Mediterranean region, where ca. 70% of all Limonium species are endemic. In this study, we sample 201 Limonium species covering all described infrageneric entities and spanning its wide geographic range, along with 64 species of other Plumbaginaceae genera, representing 23 out of 29 genera of the family. Additionally, 20 species of the sister family Polygonaceae were used as outgroup. Sequences of three chloroplast (trnL-F, matK, and rbcL) and one nuclear (ITS) loci were used to infer the molecular phylogeny employing maximum likelihood and Bayesian analyses. According to our results, within Plumbaginoideae, Plumbago forms a non-monophyletic assemblage, with Plumbago europaea sister to Plumbagella, while the other Plumbago species form a clade sister to Dyerophytum. Within Limonioideae, Ikonnikovia is nested in Goniolimon, rejecting its former segregation as genus distinct from Goniolimon. Limonium is divided into two major clades: Limonium subg. Pteroclados s.l., including L. sect. Pteroclados and L. anthericoides, and L. subg. Limonium. The latter is divided into three well-supported subclades: the monospecific L. sect. Limoniodendron sister to a clade comprising a mostly non-Mediterranean subclade and a Mediterranean subclade. Our results set the foundation for taxonomic proposals on sections and subsections of Limonium, namely: (a) the newly described L. sect. Tenuiramosum, created to assign L. anthericoides at the sectional rank; (b) the more restricted circumscriptions of L. sect. Limonium (= L. sect. Limonium subsect. Genuinae) and L. sect. Sarcophyllum (for the Sudano-Zambezian/Saharo-Arabian clade); (c) the more expanded circumscription of L. sect. Nephrophyllum (including species of the L. bellidifolium complex); and (d) the new combinations for L. sect. Pruinosum and L. sect. Pteroclados subsect. Odontolepideae and subsect. Nobiles.
- Antimalarial and Cytotoxic Activity of Native Plants Used in Cabo Verde Traditional MedicinePublication . Essoh, Anyse P.; Cassiano, Gustavo Capatti; Mandim, Filipa; Barros, Lillian; Gomes, Isildo; Medeiros, Márcia Melo; Moura, Mónica; Cravo, Pedro Vitor Lemos; Romeiras, Maria M.Medicinal plants have historically been a source of drugs in multiple applications, including the treatment of malaria infections. The Cabo Verde archipelago harbors a rich diversity of native plants, most of which are used for medicinal purposes. The present study investigated the in vitro antiplasmodial activities of four native plants from Cabo Verde (i.e., Artemisia gorgonum, Lavandula rotundifolia, Sideroxylon marginatum, and Tamarix senegalensis). Traditional preparations of these medicinal plants, namely aqueous extracts (infusions) and ethanolic extracts, were tested against both chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains using the SYBR Green detection method. The in vitro cytotoxicity was evaluated in Caco-2 and PLP2 cells using a sulforhodamine B colorimetric assay. An ethanolic extract of A. gorgonum and infusions of T. senegalensis exhibited high antiplasmodial activities (EC50 < 5 µg/mL) without cytotoxicity (GI50 > 400 µg/mL). Extracts of L. rotundifolia and S. marginatum exhibited moderate activities, with EC50 values ranging from 10–30 µg/mL. The A. gorgonum ethanolic extract showed activity toward early ring stages, and parasites treated with the T. senegalensis infusions progressed to the early trophozoite stage, although did not develop further to the late trophozoite or schizont stages. Antimalarial activities and the lack of cytotoxicity of the extracts are reported in the present study and support previous claims by traditional practitioners for the use of these plants against malaria while suggesting their ethnopharmacological usefulness as future antimalarials.
- Antimalarial and cytotoxic activity of native plants used in Cabo Verde traditional medicinePublication . Essoh, Anyse P.; Cassiano, Gustavo Capatti; Mandim, Filipa; Barros, Lillian; Gomes, Isildo; Medeiros, Márcia Melo; Moura, Mónica; Cravo, Pedro Vitor Lemos; Romeiras, Maria M.Medicinal plants have historically been a source of drugs in multiple applications, including the treatment of malaria infections. The Cabo Verde archipelago harbors a rich diversity of native plants, most of which are used for medicinal purposes. The present study investigated the in vitro antiplasmodial activities of four native plants from Cabo Verde (i.e., Artemisia gorgonum, Lavandula rotundifolia, Sideroxylon marginatum, and Tamarix senegalensis). Traditional preparations of these medicinal plants, namely aqueous extracts (infusions) and ethanolic extracts, were tested against both chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains using the SYBR Green detection method. The in vitro cytotoxicity was evaluated in Caco-2 and PLP2 cells using a sulforhodamine B colorimetric assay. An ethanolic extract of A. gorgonum and infusions of T. senegalensis exhibited high antiplasmodial activities (EC50 < 5 g/mL) without cytotoxicity (GI50 > 400 g/mL). Extracts of L. rotundifolia and S. marginatum exhibited moderate activities, with EC50 values ranging from 10–30 g/mL. The A. gorgonum ethanolic extract showed activity toward early ring stages, and parasites treated with the T. senegalensis infusions progressed to the early trophozoite stage, although did not develop further to the late trophozoite or schizont stages. Antimalarial activities and the lack of cytotoxicity of the extracts are reported in the present study and support previous claims by traditional practitioners for the use of these plants against malaria while suggesting their ethnopharmacological usefulness as future antimalarials.
- Antimalarial and Cytotoxic Activity of Native Plants Used in Cabo Verde Traditional MedicinePublication . Essoh, Anyse P.; Cassiano, Gustavo Capatti; Mandim, Filipa; Barros, Lillian; Gomes, Isildo; Medeiros, Márcia Melo; Moura, Mónica; Cravo, Pedro Vitor Lemos; Romeiras, Maria M.Medicinal plants have historically been a source of drugs in multiple applications, including the treatment of malaria infections. The Cabo Verde archipelago harbors a rich diversity of native plants, most of which are used for medicinal purposes. The present study investigated the in vitro antiplasmodial activities of four native plants from Cabo Verde (i.e., Artemisia gorgonum, Lavandula rotundifolia, Sideroxylon marginatum, and Tamarix senegalensis). Traditional preparations of these medicinal plants, namely aqueous extracts (infusions) and ethanolic extracts, were tested against both chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains using the SYBR Green detection method. The in vitro cytotoxicity was evaluated in Caco-2 and PLP2 cells using a sulforhodamine B colorimetric assay. An ethanolic extract of A. gorgonum and infusions of T. senegalensis exhibited high antiplasmodial activities (EC50 < 5 μg/mL) without cytotoxicity (GI50 > 400 μg/mL). Extracts of L. rotundifolia and S. marginatum exhibited moderate activities, with EC50 values ranging from 10–30 μg/mL. The A. gorgonum ethanolic extract showed activity toward early ring stages, and parasites treated with the T. senegalensis infusions progressed to the early trophozoite stage, although did not develop further to the late trophozoite or schizont stages. Antimalarial activities and the lack of cytotoxicity of the extracts are reported in the present study and support previous claims by traditional practitioners for the use of these plants against malaria while suggesting their ethnopharmacological usefulness as future antimalarials.
- As árvores em números: registo e discussão dos resultadosPublication . Soares, Ana Luísa; Cunha, Ana Raquel; Vasconcelos, Teresa; Rego, Francisco Castro; Monteiro, José; Arsénio, Pedro; Forte, Paulo; Azambuja, Sónia Talhé; Romeiras, Maria M.Capítulo 2. Pretendemos, neste capítulo, apresentar os resultados e evidenciar a composição arbórea de cada jardim. A identidade própria de cada um deve-se ao contexto histórico e cultural da construção que terá influenciado o seu traçado, mas também à sua localização e topografia, numa cidade conhecida pelas suas sete colinas e pela envolvente urbanística. Cada jardim é também marcado pelo seu próprio traçado e pela composição e estética dos seus planos de plantação, que caracterizam a sua diversidade arbórea. A realização deste levantamento permitiu obter informação sobre vários aspetos relativos à diversidade botânica e à composição dos jardins estudados. O desafio é, pois, mostrar através do número de espécimes (27.610) e de espécies (799) inventariados, a diversidade e riqueza do património arbóreo existente em Lisboa. Com base nos resultados apurados, apresentam-se de seguida algumas das principais conclusões.
- Assessing the conservation of Miombo timber species through an integrated index of anthropogenic and climatic threatsPublication . Catarino, Silvia; Romeiras, Maria M.; Pereira, José M. C.; Figueira, RuiAim: Angolan Miombo woodlands, rich in timber species of the Leguminosae family, go through one of the highest rates of deforestation in sub-Saharan Africa. This study presents, on the basis of updated information of the distribution of Leguminosae timber species native to Angola, an integrated index framing the main threats for trees, which aims to support new conservation measures. Location: Sub-Saharan Africa, Republic of Angola. Methods: The current distribution areas of six Leguminosae timber species (i.e., Afzelia quanzensis, Brachystegia spiciformis, Guibourtia coleosperma, Isoberlinia angolensis, Julbernardia paniculata, and Pterocarpus angolensis) were predicted through ensemble modeling techniques. The level of threat to each species was analyzed, comparing the species potential distribution with a threat index map and with the protected areas. The threat index of anthropogenic and climatic factors encompasses the effects of population density, agriculture, proximity to roads, loss of tree cover, overexploitation, trends in wildfires, and predicted changes in temperature and precipitation. Results: Our results revealed that about 0.5% of Angola's area is classified as of “Very high” threat, 23.9% as “High” threat, and 66.5% as “Moderate” threat. Three of the studied species require special conservation efforts, namely B. spiciformis and I. angolensis, which have a large fraction of predicted distribution in areas of high threat, and G. coleosperma since it has a restricted distribution area and is one of the most valuable species in international markets. The priority areas for the conservation of Leguminosae timber species were found in Benguela and Huíla.Main conclusions: This study provides updated data that should be applied to inform policymakers, contributing to national conservation planning and protection of native flora in Angola. Moreover, it presents a methodological approach for the predictions of species distribution and for the creation of a threat index map that can be applied in other poorly surveyed tropical regions.
- Assessing the vulnerability of urban tree species to climate change: The case study of Lisbon gardensPublication . Cunha, Ana Raquel; Soares, Ana Luísa; Catarino, Sílvia; Duarte, Maria Cristina; Romeiras, Maria M.To mitigate the effects of climate change on urban green spaces, adaptive strategies are required, particularly regarding tree species. Lisbon is a most vulnerable city to extreme climate events and the performance and management of the numerous and diverse trees found in its gardens and parks are of much concern. We evaluated the vulnerability of such trees to predicted future Lisbon climates using the Climate Assessment Tool (Climate Change Alliance of Botanic Gardens, 2024) and inventories from 63 historical gardens and parks, including three botanical gardens. With the extensive information of the latter we: (i) identified and classified the species according to biogeographical origins; (ii) pinpointed those most vulnerable to, or favoured by climate change; and (iii) assessed the vulnerability of each studied site, according to the species present, their risk level and abundance. Among the selected 318 taxa (corresponding to 19,579 trees), the Palaearctic biogeographical region predominates. The highest risk levels were found in 50 % (77 %, for the most pessimistic climate scenario) of the Palaearctic species, which include many native taxa. Conversely, about 56 % of the Neotropical species are predicted to perform better under the worst climate change scenario. Only one of the ten most abundant tree species in Lisbon – Jacaranda mimosifolia – might remain invulnerable. Management plans for most Lisbon green spaces must therefore reexamine the use of Palaearctic species and tackle challenging adjustments, including the gradual replacement of familiar species (increasingly more difficult to maintain) by others with better performance under future climate conditions.
- Assessment of the vulnerability of coastal mangrove ecosystems in MozambiquePublication . Charrua, Alberto B.; Bandeira, Salomão O.; Catarino, Silvia; Cabral, Pedro; Romeiras, Maria M.Mangrove forests are among the most productive ecosystems on Earth. However, there is still insufficient information available for strategic prediction of conservation and management intervention, particularly in the case of Mozambique. This country has the longest coastline and mangrove forests of Eastern Africa, but is prone to global climate hazards. Using recent field data and environmental parameters subjected to the Variance Inflation Factor (VIF) collinearity test (bioclimatic variables, slop, salinity, land cover, and elevation), we ran MaxEnt to model the distribution of mangrove forests based on occurrence data of the most emblematic and representative mangrove species in Mozambique (Avicennia marina and Rhizophora mucronata). Moreover, in order to understand which areas should be prioritized for management interventions on mangroves and costal dunes, an Exposure Index (EI) to climate hazards and erosion was compared with the potential distribution of these species. Our results showed that average wind speed of summer season, land surface elevation, Mean Diurnal Range, and saltwater exposure (salinity) were determinant on the distribution models of both species. The central coastal region of Mozambique (so-called swamp coast) presents the largest potentially suitable areas for mangroves species occurrence, having the highest levels of exposure. We also found that A. marina presents a higher EI than R. mucronata. The scarcity of studies concerning the central region of Mozambique; which was recently devastated by cyclone Idai (category four, 2019), which hit Mozambique and the neighbouring countries, reinforce the urgency for management intervention. The findings of this study should be used by managers and decision makers to promote best practices to safeguard lives and people's livelihoods and assets threatened by coastal climate hazards and anthropogenic impacts.
- Bayesian methods to analyze historical collections in time and space: a case study using Cabo Verde endemic floraPublication . Romeiras, Maria M.; Carine, Mark; Duarte, Maria Cristina; Catarino, Silvia; Dias, Filipe S.; Borda-de-Água, LuísBiological collections, including herbarium specimens, are unique sources of biodiversity data presenting a window on the history of the development and accumulation of knowledge of a specific geographical region. Understanding how the process of discovery impacts that knowledge is particularly important for oceanic islands which are often characterized by both high levels of endemic diversity and high proportions of threatened taxa. The archipelagos of the Macaronesian region (i.e. Azores, Canaries, Savages, Madeira, and Cabo Verde) have been the focus of attention for scientific expeditions since the end of the 17th century. However, there is no integrated study describing the historical process of collecting, discovery and description of its flora. Using as a case study the Cabo Verde endemic angiosperm flora, we review the history of collecting in the flora and apply a Bayesian approach to assess the accumulation of species discovery, through time and space across the nine islands of the archipelago. Our results highlight the central role not only of natural characteristics (e.g. area, age, maximum altitude and average value of the terrain ruggedness index) but also historical factors (i.e. the location of major harbors) for the development of knowledge of the flora. The main factors that have determined the process of species description in the archipelago and how this impact our understanding of diversity patterns across archipelagos are discussed