Browsing by Author "Duarte, Maria Cristina"
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- Alguns dados sobre a flora e a vegetação do litoral de Cabo VerdePublication . Costa, José Carlos; Rivas-Martinez, Salvador; Duarte, Maria Cristina; Gomes, Isildo; Lousã, Mário
- 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.
- 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
- 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.
- Cabo Verde’s Poaceae Flora: A Reservoir of Crop Wild Relatives Diversity for Crop ImprovementPublication . Rocha, Vanézia; Duarte, Maria Cristina; Catarino, Silvia; Duarte, Ivani; Romeiras, Maria M.Africa is home to important centers of origin and diversity of crop wild relatives (CWR), including many species adapted to adverse agroecological conditions, namely drought and poor soils. Plant genetic resources from Cabo Verde Islands have been poorly explored for their potential to supplement the genetic pool of cultivated species. In this paper we identify Cabo Verde's CWR from the Poaceae family and provide a checklist of priority CWR taxa, highlighting those of particular conservation concern and the areas which should be the focus of the most intensive conservation efforts in these islands. Our results revealed that Cabo Verde archipelago is an important center of CWR diversity of West African crop millets, namely fonio (e.g., white fonio, Digitaria exilis, and black fonio, Digitaria iburua) and other African millets [e.g., pearl millet (Cenchrus americanus = Pennisetum glaucum), teff millet (Eragrostis tef), finger millet (Eleusine coracana), barnyard millet (Echinochloa colona), proso millet (Panicum miliaceum), and foxtail millet (Setaria italica)], which represent a diverse group of cereal crops, and important components in agriculture and food security of this country. Also, hotspot areas of diversity for in situ conservation were identified in Cabo Verde, as well as several populations occurring under extreme habitats conditions that are well adapted to drylands and poor soils. The evaluation of their potential for new ecologically important adaptive characteristics associated with tolerance to abiotic stresses is discussed. The survey of international Germplasm Banks revealed that very few accessions from Cabo Verde are conserved, contributing to the loss of genetic diversity of plant genetic resources in this archipelago. Particularly, the diversity of millets and the associated indigenous knowledge are critical for the food security and cultural identity of many poor farmers in Cabo Verde.
- Cashew as a high agricultural commodity in West Africa: insights towards sustainable production in Guinea-BissauPublication . Monteiro, Filipa; Catarino, Luís; Batista, Dora; Indjai, Bucar; Duarte, Maria Cristina; Romeiras, MariaIn Sub-Saharan Africa, the West African region has highly diverse agro-climatic conditions, which grant the potential for a remarkable agricultural production of a great diversity of crops. Since the 1980s, the production volumes of most crops have grown vigorously for both domestic and export markets. Traditional food crops—such as rice, groundnuts and sorghum—have been replaced by cash crops, namely cashew. Among the main cashew production areas, West Africa is the most recent and dynamic in the world, accounting for 45% of the worldwide production of cashew nuts in 2015. In consequence, cashew cultivation has acquired an important position in West African smallholder farming, providing positive economic and social effects. In this paper, we provide an overview of the cashew production system in the West African region, using Guinea-Bissau as a case study. In particular, we present some viewpoints concerning the impact of cashew production and discuss how the strong dependence on a single cash crop can compromise the local livelihoods and food security. Finally, some insights are given towards the sustainable production of cashew in the face of the recent risks affecting the agricultural sector in West Africa
- Chromolaena odorata invasion in Guinea-Bissau (West Africa): first records and trends of expansionPublication . Catarino, Luís; Indjai, Bucar; Duarte, Maria Cristina; Monteiro, FilipaThe Siam weed, Chromolaena odorata (L.) R. M. King & H. Rob. (Asteraceae), is recognized as one of the world’s worst tropical weeds. It is a perennial herb or shrub native to the neotropics that has become invasive across the tropical regions of Africa, Asia and Oceania. The species was introduced in 1937 in Nigeria and later spread to neighboring countries. Its presence and effects have been documented in the upland zones of almost all West African countries. Although, until the present study, the species had not been recorded in Guinea-Bissau, its presence in the country was very likely. In this work we document, for the first time, the invasion of Guinea-Bissau by C. odorata, assessing its present distribution and reporting effects, local uses and common names. Dispersal trends, potential consequences of its expansion and recommendations for management and control are also presented
- Chromolaena odorata invasion in Guinea-Bissau (West Africa): first records and trends of expansionPublication . Catarino, Luís; Indjai, Bucar; Duarte, Maria Cristina; Monteiro, FilipaThe Siam weed, Chromolaena odorata (L.) R. M. King & H. Rob. (Asteraceae), is recognized as one of the world’s worst tropical weeds. It is a perennial herb or shrub native to the neotropics that has become invasive across the tropical regions of Africa, Asia and Oceania. The species was introduced in 1937 in Nigeria and later spread to neighboring countries. Its presence and effects have been documented in the upland zones of almost all West African countries. Although, until the present study, the species had not been recorded in Guinea-Bissau, its presence in the country was very likely. In this work we document, for the first time, the invasion of Guinea-Bissau by C. odorata, assessing its present distribution and reporting effects, local uses and common names. Dispersal trends, potential consequences of its expansion and recommendations for management and control are also presented.
- Conservation and sustainable use of the medicinal Leguminosae plants from AngolaPublication . Catarino, Silvia; Duarte, Maria Cristina; Costa, Esperança; Carrero, Paula Garcia; Romeiras, Maria M.Leguminosae is an economically important family that contains a large number of medicinal plants, many of which are widely used in African traditional medicine. Angola holds a great socio-cultural diversity and is one of the richest floristic regions of the world, with over 900 native Leguminosae species. This study is the first to assess the medicinal uses of the legumes in Angola and provides new data to promote the conservation and the sustainable use of these unique resources. We document the ethnobotanical knowledge on Angola by reviewing the most important herbarium collections and literature, complemented by recent field surveys. Our results revealed that 127 native legume species have medicinal uses and 65% of them have other important uses by local populations. The species with most medicinal applications are Erythrina abyssinica, Bauhinia thonningii and Pterocarpus angolensis. The rich flora found in Angola suggests an enormous potential for discovery of new drugs with therapeutic value. However, the overexploitation and the indiscriminate collection of legumes for multiple uses such as forage, food, timber and medical uses, increases the threats upon the native vegetation. Efforts to assess the conservation status of these species are urgently needed, and future actions should promote the sustainable use of medicinal plants in Angola together with the implementation of conservation strategies.
- Conservation priorities for African Vigna species: Unveiling Angola’s diversity hotspotsPublication . Catarino, Sílvia; Rangel, Josefa; Darbyshire, Iain; Costa, Esperança; Duarte, Maria Cristina; Romeiras, Maria M.It is widely recognized that the conservation of the Crop Wild Relatives (CWR) in their wild habitats is fundamental to ensure the continuous supply of novel genetic material, crucial for future crop improvement. Vigna unguiculata (cowpea) and V. subterranea (bambara groundnut) are amongst the most significant African legumes as sources of food and fodder. In this study we investigated the diversity of Vigna species in Angola, to identify hotspot areas for their in situ conservation, and thus underpin future food security in Sub- Saharan Africa. Based on four criteria (i.e. potential utilization for crop improvement, threat status, ethnobotanical value, and geographical distribution) we prioritize Vigna CWR for conservation actions in Angola. Our results reveal that 28 Vigna species occur in Angola, two of which are endemic (V. mendesii and V. ramanniana). These species are unevenly distributed across the country, with greater dominance in the central-north and western areas, where four hotspot areas (Saurimo, Serra da Chela, N’dalatando, and Huambo) are identified. However, significant gaps in the current in situ conservation strategies are highlighted by our results, since the CWR diversity hotspots remain unprotected and only nine of the 28 Vigna species are recorded in protected areas. Moreover, in light of the fact that only one accession of Vigna collected in Angola exists in genebanks globally at present, we recommend a targeted seed collecting programme to support future management and ex situ conservation of plant genetic resources in Angola. Our study calls attention to the fact that Angola, together with Zambia, has the highest Vigna species richness in Sub- Saharan Africa, and provides new data and tools for the sustainable use of these species in crop improvement.