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Cercosporoid fungi (Mycosphaerellaceae, Mycosphaerellales, Ascomycota) are one of the largest and most diverse groups of hyphomycetes causing a wide range of diseases of economically important plants as well as of plants in the wild. Although more than 6000 species are known for this group, the documentation of this fungal group is far from complete. Especially in the tropics, the diversity of cercosporoid fungi is poorly known. The present study aims to identify and characterise cercosporoid fungi collected on host plants belonging to Fabaceae in Benin, West Africa. Information on their morphology, host species and DNA sequence data (18S rDNA, 28S rDNA, ITS and tef1) is provided. DNA sequence data were obtained by a simple and non-culture-based method for DNA isolation which has been applied for cercosporoid fungi for the first time in the context of the present study. Among the loci used for the phylogenetic analysis, tef1 provided the best resolution together with the multigene dataset. Species delimitation in many cases, however, was only possible by combining molecular sequence data with morphological characteristics. Based on forty specimens recently collected in Benin, 18 species are presented with morphological descriptions, illustrations and sequence data. Among these, six species in the genus Cercospora and two species in Pseudocercospora are proposed as species new to science. The newly described species are Cercospora (C.) beninensis on Crotalaria macrocalyx, C. parakouensis on Desmodium tortuosum, C. rhynchophora on Vigna unguiculata, C. vignae-subterraneae on Vigna subterranea, C. tentaculifera on Vigna unguiculata, C. zorniicola on Zornia glochidiata, Pseudocercospora sennicola on Senna occidentalis and Pseudocercospora tabei on Vigna unguiculata. Eight species of cercosporoid fungi are reported for Benin for the first time, three of them, namely C. cf. canscorina, C. cf. fagopyri and C. phaseoli-lunati are new for West Africa. The presence of two species of cercosporoid fungi on Fabaceae previously reported from Benin, namely Nothopassalora personata and Passalora arachidicola, is confirmed.
Background: The West African country of Burkina Faso (BFA) is an example for the enduring importance of traditional plant use today. A large proportion of its 17 million inhabitants lives in rural communities and strongly depends on local plant products for their livelihood. However, literature on traditional plant use is still scarce and a comprehensive analysis for the country is still missing.
Methods: In this study we combine the information of a recently published plant checklist with information from ethnobotanical literature for a comprehensive, national scale analysis of plant use in Burkina Faso. We quantify the application of plant species in 10 different use categories, evaluate plant use on a plant family level and use the relative importance index to rank all species in the country according to their usefulness. We focus on traditional medicine and quantify the use of plants as remedy against 22 classes of health disorders, evaluate plant use in traditional medicine on the level of plant families and rank all species used in traditional medicine according to their respective usefulness.
Results: A total of 1033 species (50%) in Burkina Faso had a documented use. Traditional medicine, human nutrition and animal fodder were the most important use categories. The 12 most common plant families in BFA differed considerably in their usefulness and application. Fabaceae, Poaceae and Malvaceae were the plant families with the most used species. In this study Khaya senegalensis, Adansonia digitata and Diospyros mespiliformis were ranked the top useful plants in BFA. Infections/Infestations, digestive system disorders and genitourinary disorders are the health problems most commonly addressed with medicinal plants. Fabaceae, Poaceae, Asteraceae, Apocynaceae, Malvaceae and Rubiaceae were the most important plant families in traditional medicine. Tamarindus indica, Vitellaria paradoxa and Adansonia digitata were ranked the most important medicinal plants.
Conclusions: The national-scale analysis revealed systematic patterns of traditional plant use throughout BFA. These results are of interest for applied research, as a detailed knowledge of traditional plant use can a) help to communicate conservation needs and b) facilitate future research on drug screening.
Although there is an increasing need for data in ecological studies, many datasets are still lost or not sufficiently visible due to a lack of appropriate data archives. With the West African Data and Metadata Repository, we present a secure long-term archive for a data-poor region allowing detailed documentation by metadata following the EML standard and giving data holders the opportunity to define levels of data access and conditions of use. This article gives an overview of structure, functions and content. The repository is online at the URL http://westafricandata.senckenberg.de.
This thesis develops a conceptual framework for a better understanding of the impact of slow-onset climate and environmental changes on human migration in developing countries. Its regional focus is on the West African Sahel, where the majority of the population depends on agriculture and thus is highly vulnerable to environmental changes. Migration from fragile environments is predominantly considered one of several household strategies to adapt to and minimise the risk of environmental stress. Based on qualitative and quantitative data from two selected rural study areas, Bandiagara in Mali and Linguère in Senegal, this thesis analyses the drivers of migration from the two areas.
The findings illustrate that, even though people highly depend on the natural environment, migration motives are manifold and that migration often is not a household strategy to cope with environmental changes. Although environmental conditions shape migration in the region and the migrants’ support is crucial for most households, environmental stress plays a relatively small role as a driver of migration - at least in Mali, where it is considerably less important than in Senegal. On the contrary, migration is often driven by better opportunities elsewhere rather than by livelihood stressors in the home area. Particularly the migration of young people is often an individual rather than a household decision and influenced by individual aspirations, such as aspirations for consumer goods or a better future, rather than by environmental stress.
This thesis claims that research should consider people’s capabilities to migrate or to stay as well as their individual aspirations and preferences - in addition to the household’s needs and the opportunities elsewhere. This is important in order to explain why some people stay in and others migrate from an area affected by environmental stress, though living under similar conditions. Depending on people’s capabilities to choose freely between staying and migrating and their preferences and aspirations for one or the other activity, people can either be “voluntary migrants”, “voluntary non-migrants”, “forced migrants” or “trapped people”.
Moreover, it is important to consider social trends and transformation processes in the analysis of the linkages between environment change and migration. Higher education levels and aspirations to a “modern” lifestyle among young people, for instance, might decrease the impact of environmental factors on migration, despite worsening environmental conditions.
Particularly in savannas, termites are ecosystem engineers and a keystone group in ecology. For the understanding of the savanna vegetation, mound building termites are of particular interest. Due to their special soil chemistry and physical structure, termite mounds often host other plants than the surrounding savanna. As our knowledge of the specific contribution of mound-building termites to overall savanna diversity and ecosystem dynamics doubtlessly is not complete, this paper summarises the state of the art in order to stimulate further research. According to the research interest of the authors, focus is laid on the West African savanna and on the genus Macrotermes.
Non-Timber Forest Products (NTFPs) make a major contribution to the livelihoods and diets of rural households in the savanna ecosystems of West Africa. However, land use change and climatic variability might affect their availability in the future. Based on a survey among 227 households in Northern Benin, we investigated local substitution patterns for the seeds of the three socio-economically most important NTFP-species in the region, Vitellaria paradoxa, Adansonia digitata and Parkia biglobosa, being major sources for protein, fat, and micronutrients in local daily diets. Our study compared substitution patterns between, firstly, three income groups, to assess whether a households’ socio-economic status has an influence on the choice of surrogates (low cost vs. more costly options). Secondly, we compared substitution patterns between the five major ethnic groups in the study region (the Fulani, the Bariba, the Ditammarie, the Kabiyé and the Yom). The choice of substitutes differed significantly across income groups. However, the poorest households clearly show to be the most vulnerable: up to 30 % of the sampled households stated they would lack an adequate replacement for the NTFPs in question. Furthermore, ethnic affiliation showed to have a considerable impact on the preferred alternative products due to underlying cultural traditions of plant use. Subsequently, aiming at maintaining – and enhancing – the local supply of V. paradoxa, P. biglobosa and A. digitata in order to secure their contributions to local diets, local land use policy should have a particular focus on their ethnic-conditioned use and particularly the specific requirements of the poorest community members.
Knowledge about the herbaceous layer in relation to environmental factors in West African savannas is still scarce. Early life-cycle events like germination of the herbaceous species are of special interest, as these stages can play critical roles in establishing of the plants and determine population and community dynamics. We aim to assess intraspecific differences in the germinability of herbaceous savanna species with respect to environmental conditions to reveal adaptations in this early life cycle stage. The study was conducted in the Sudanian savanna of Burkina Faso in West Africa. We collected seeds of two annual herbs (Chamaecrista mimosoides, Spermacoce stachydea) along a climatic gradient from different habitats and land use types and conducted germination experiments under equal conditions in climate chambers. For both species several environmental factors showed a significant impact on the germination rates. While higher precipitation caused an increase in the germination rate only for S. stachydea, habitat conditions had a significant influence for both species. Intermediate habitats with balanced soil moisture caused an enhancement of the germination success. Moreover shrub cover had a positive effect on the germinability of C. mimosoides, whereas the germinability of S. stachydea decreased due to an increasing herbaceous cover. The study showed that certain environmental factors are able to modify the intraspecific variability of the germinability trait, which might affect the establishment of the species populations.
Gender in Fulani proverbs
(2018)
Presented paper deals with Fulani people of West Africa and with the influence of their way of life on their language. One part of the Fulani people lives nomadic pastoral live, meanwhile another part is sedentary, living in the towns. The authors of the paper pay their attention to the the gender of Fulani proverbs which reflects the way of life of Fulani people.
Until recently the Nigerian Nok Culture had primarily been known for its terracotta sculptures and the existence of iron metallurgy, providing some of the earliest evidence for artistic sculpting and iron working in sub-Saharan Africa. Research was resumed in 2005 to understand the Nok Culture phenomenon, employing a holistic approach in which the sculptures and iron metallurgy remain central, but which likewise covers other archaeological aspects including chronology, settlement patterns, economy, and the environment as key research themes. In the beginning of this endeavour the development of social complexity during the duration of the Nok Culture constituted a focal point. However, after nearly ten years of research and an abundance of new data the initial hypothesis can no longer be maintained. Rather than attributes of social complexity like signs of inequality, hierarchy, nucleation of settlement systems, communal and public monuments, or alternative African versions of complexity discussed in recent years, it has become apparent that the Nok Culture, no matter which concept is followed, developed complexity only in terms of ritual. Relevant information and arguments for the transition of the theoretical background are provided here.