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2.
Sci Rep ; 13(1): 10323, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365263

RESUMO

Understanding the changing plant ecosystems that existed in East Africa over the past millennia is crucial for identifying links between habitats and past human adaptation and dispersal across the region. In the Horn of Africa, this task is hampered by the scarcity of fossil botanical data. Here we present modelled past vegetation distributions in Ethiopia from the Last Glacial Maximum (LGM) to present at high spatial and temporal resolution. The simulations show that, contrary to long-standing hypotheses, the area covered by Afromontane forests during the Late Glacial was significantly larger than at present. The combined effect of low temperatures and the relative rainfall contribution sourced from the Congo Basin and Indian Ocean, emerges as the mechanism that controlled the migration of Afromontane forests to lower elevations. This process may have enabled the development of continuous forest corridors connecting populations that are currently isolated in mountainous areas over the African continent. Starting with the Holocene, the expansion of forests began to reverse. This decline intensified over the second half of the Holocene leading to a retreat of the forests to higher elevations where they are restricted today. The simulations are consistent with proxy data derived from regional pollen records and provide a key environmental and conceptual framework for human environmental adaptation research.


Assuntos
Ecossistema , Florestas , Humanos , África Oriental , Congo , Etiópia
3.
Biodivers Data J ; 8: e54205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714013

RESUMO

BACKGROUND: The W National Park and its two hunting zones represent a unique ecosystem in Burkina Faso for biodiversity conservation. This study aims at providing a detailed view of the current state of the floristic diversity as a baseline for future projects aiming at protecting and managing its resources. We combined intensive inventories and distribution records from vegetation plots, photo records and herbarium collections. NEW INFORMATION: This is the first comprehensive checklist of vascular plants of the Burkina Faso part of the transborder W National Park. With 721 documented species including 19 species new to Burkina Faso, the Burkina Faso part of the W National Park is, so far, the nature reserve with most plant species in Burkina Faso. To a large extent, this may be assigned to its high habitat diversity and moderate degree of disturbance, but also to a relatively large area within an even larger complex of neighbouring protected areas, as well as comprehensive spatial, ecological and seasonal sampling efforts. However, as a World Heritage Site and regarding the current general context of insecurity, the W National Park and the entire WAP Complex require more international attention in order to ensure its conservation.

4.
J Ethnobiol Ethnomed ; 11: 9, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25971673

RESUMO

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.


Assuntos
Medicinas Tradicionais Africanas/estatística & dados numéricos , Plantas Medicinais , Burkina Faso/epidemiologia , Conservação dos Recursos Naturais , Humanos , Medicinas Tradicionais Africanas/métodos , Fitoterapia/métodos , Fitoterapia/estatística & dados numéricos
5.
Environ Monit Assess ; 184(2): 655-78, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21448628

RESUMO

The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1 km(2) and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , África , Animais , Biota , Monitoramento Ambiental/normas , Desenvolvimento Vegetal , Plantas/classificação
6.
J Am Soc Mass Spectrom ; 16(7): 1151-61, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15921924

RESUMO

A new version of the single-reference-extended kinetic method is presented in which direct entropy correction is incorporated. Results of calibration experiments with the monodentate base pyridine and the bidentate base ethylenediamine are presented for which the method provides proton affinities in excellent agreement with published values and reasonable predictions for the protonation entropies. The method is then used to determine the proton affinity and protonation entropy of the non-protein amino acid beta-oxalylaminoalanine (BOAA). The PA of BOAA is found to be 933.1 +/- 7.8 kJ/mol and a prediction for the protonation entropy of -39 J mol(-1) K(-1) is also obtained, indicating a significant degree of intramolecular hydrogen bonding in the protonated form. These results are supported by hybrid density functional theory calculations at the B3LYP/6-311++G**//B3LYP/6-31+G* level. They indicate that the preferred site of protonation is the alpha-nitrogen atom (PA = 935.0 kJ/mol) and that protonated BOAA has a strong hydrogen bond between the hydrogen on the alpha-amino group and one of the carbonyl oxygen atoms on the side chain.


Assuntos
Diamino Aminoácidos/química , Entropia , Neurotoxinas/química , Prótons , Etilenodiaminas/química , Fabaceae/química , Ligação de Hidrogênio , Cinética , Plantas Medicinais/química , Piridinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos
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