23 research outputs found
Crops Diversification and the Role of Orphan Legumes to Improve the Sub-Saharan Africa Farming Systems
Agriculture is the main economic revenue in sub-Saharan African countries, playing a key role on smallholder livelihoods as household incomes and as food. Food insecurity is known to increase with the inevitable climate changes, which already affect the major farming systems, sub-Saharan Africa (SSA) being particularly susceptible, mostly due to the high dependence of rainfall for crop cycles. As such, to promote food security in a long run, new farming systems have to become more sustainable and productive at the same time. In this chapter, a global overview of major farming systems in sub-Saharan Africa is provided, and current and future production scenarios are discussed. Moreover, some of the major pillars under the sustainable land use intensification are highlighted, and the potential of the undervalued African legumes toward a sustainable crop production is debated. Finally, an outline of key opportunities to diversify cropping systems is explored along with the benefits associated to integration of local and “orphan legumes” that are considered. It is argued that the use of these “orphan legumes” and the implementation of appropriated management approaches will promote a sustainable production of more food from the same land area, relying on mutually beneficial ecological relationships and reducing environmental impacts
Species Diversity and Endemicity in the Angolan Leguminosae Flora
Angola has a great diversity of species and ecosystems and a high level of endemism. However, knowledge of the native flora remains very incomplete and outdated. Leguminosae is the largest family in the country, including many species which are of local or more regional economic importance. Based on an extensive review of bibliographic sources, natural history collections, and online databases, the checklist of Angolan Leguminosae plants was updated, including data on their native distribution, conservation status, and principal uses. The endemic taxa were the subject of additional investigation, including the main habitat, the number of collections preserved in herbaria, and the locality of the first collection. We identified 953 Leguminosae taxa occurring in Angola, of which 165 are endemic to the country. Among the 180 genera found, Crotalaria (136) and Indigofera (96) have the highest number of taxa. Almost half of the studied species have important applications, mainly in traditional medicine (385), forage (267), timber (188), and food (120). Nevertheless, only 27.7% have been assessed according to the IUCN Red List and 10 species are classified as threatened. Thirty-three endemics are known only from the type specimen, revealing the lack of knowledge on these species and the need for further field research. More than 30 type specimens were collected in the Serra da Chela, which highlights the importance of this region for biodiversity conservation.info:eu-repo/semantics/publishedVersio
Current status and trends in Cabo Verde agriculture
With climate change, drought is expected to increase, and its negative impacts will be
particularly important in developing countries, usually with rainfall-dependent agriculture. The Cabo
Verde archipelago is characterized by limited resources, remoteness, vulnerability to natural disasters,
and a fragile environment. In this study, we provide the first report of the current status and trends of
agriculture in Cabo Verde. We present data on the current performance of agricultural production
areas in these islands and discuss them in terms of their most important natural constraint, water. Also,
we assess the impact of institutional strategies on crop production and evaluate recent mechanisms
that have been engaged towards agrarian development in this archipelago. Our results show that,
among the ten Cabo Verde Islands, Santiago has the largest area used for agriculture (52.5%), followed
by Santo Antão (16%) and Fogo (15.8%), and that rainfed farming dominates in all of them. The staple
crops, such as maize and beans, are produced through rainfed subsistence farming, whereas irrigated
crops (i.e., sugarcane, tomatoes) are mostly grown for commercial purposes. The prolonged drought
periods, exposure, erosion and soil degradation, which led to increasing desertification over the last
decades, have been identified as the main constraints to agrarian development across the ten islands
of the archipelago. The strategies of Cabo Verde government to mitigate water scarcity through
small-scale irrigation based mainly on small dams and drip irrigation technology have a marked
effect on agricultural production in the predominantly arid and semi-arid areas of this archipelagoinfo:eu-repo/semantics/publishedVersio
Flora and natural resources of Cabo Verde Islands
Este Livro de Resumos contém informação, ordenada por tópicos, sobre
as comunicações orais e posters apresentados no simpósio organizado no
âmbito do projeto “CVAgrobiodiversity - Climate changes and plant genetic
resources: the overlooked potential of Cabo Verde’s endemic flora” financiado
pela FCT/Aga Khan Network e coordenado pelo Instituto Superior de
Agronomia (ISA) da Universidade de Lisboa, Portugal.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
A Vegetação das Ilhas de Cabo Verde
Situado no Atlântico Oriental, o arquipélago de Cabo Verde integra dez ilhas
totalizando 4033 km2 de superfície cuja diversidade geomorfológica e posição
geográfica ditam uma diversidade climática que, naturalmente, se reflecte num
património biológico muito diversificado.
Face à escassez de recursos naturais e às características climáticas
especialmente limitantes, a
subsistência das populações caboverdianas
acenta principalmente nas
actividades agrícolas e pecuárias
que, praticadas de forma extensiva,
levou a uma forte degradação dos
ecossistemas naturais
Reserva Natural de Santa Luzia (Cabo Verde): Guia Ilustrado da Flora e Vegetação
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
Spatial and temporal trends of burnt area in Angola: implications for natural vegetation and protected area management
Fire is a key driver of natural ecosystems in Africa. However, human activity and
climate change have altered fire frequency and severity, with negative consequences for biodiversity
conservation. Angola ranks among the countries with the highest fire activity in sub-Saharan Africa.
In this study, we investigated the spatial and temporal trends of the annual burnt area in Angola,
from 2001 to 2019, and their association with terrestrial ecoregions, land cover, and protected areas.
Based on satellite imagery, we analyzed the presence of significant trends in burnt area, applying the
contextual Mann–Kendall test and the Theil–Sen slope estimator. Data on burnt areas were obtained
from the moderate-resolution imaging spectroradiometer (MODIS) burnt area product and the
analyses were processed in TerrSet. Our results showed that ca. 30% of the country’s area burned
every year. The highest percentage of annual burnt area was found in northeast and southeast Angola,
which showed large clusters of decreasing trends of burnt area. The clusters of increasing trends
were found mainly in central Angola, associated with savannas and grasslands of Angolan Miombo
woodlands. The protected areas of Cameia, Luengue-Luiana, and Mavinga exhibited large areas
of decreasing trends of burnt area. Conversely, 23% of the Bicuar National Park was included in
clusters of increasing trends. Distinct patterns of land cover were found in areas of significant trends,
where the clusters of increasing trends showed a higher fraction of forest cover (80%) than the clusters
of decreasing trends (55%). The documentation of burnt area trends was very important in tropical
regions, since it helped define conservation priorities and management strategies, allowing more
effective management of forests and fires in countries with few human and financial resourcesinfo:eu-repo/semantics/publishedVersio
Topography-driven isolation, speciation and a global increase of endemism with elevation
Aim: Higher-elevation areas on islands and continental mountains tend to be separated by longer distances, predicting higher endemism at higher elevations; our study is the first to test the generality of the predicted pattern. We also compare it empirically with contrasting expectations from hypotheses invoking higher speciation with area, temperature and species richness.
Location: Thirty-two insular and 18 continental elevational gradients from around the world.
Methods: We compiled entire floras with elevation-specific occurrence information, and calculated the proportion of native species that are endemic (‘percent endemism’) in 100-m bands, for each of the 50 elevational gradients. Using generalized linear models, we tested the relationships between percent endemism and elevation, isolation, temperature, area and species richness.
Results: Percent endemism consistently increased monotonically with elevation, globally. This was independent of richness–elevation relationships, which had varying shapes but decreased with elevation at high elevations. The endemism–elevation relationships were consistent with isolation-related predictions, but inconsistent with hypotheses related to area, richness and temperature.
Main conclusions: Higher per-species speciation rates caused by increasing isolation with elevation are the most plausible and parsimonious explanation for the globally consistent pattern of higher endemism at higher elevations that we identify. We suggest that topography-driven isolation increases speciation rates in mountainous areas, across all elevations and increasingly towards the equator. If so, it represents a mechanism that may contribute to generating latitudinal diversity gradients in a way that is consistent with both present-day and palaeontological evidence