Culture, Trade and Diaspora in Pre-Atlantic Western Africa

Author(s):  
Toby Green
Keyword(s):  
2016 ◽  
Vol 13 (11) ◽  
pp. 3343-3357 ◽  
Author(s):  
Zun Yin ◽  
Stefan C. Dekker ◽  
Bart J. J. M. van den Hurk ◽  
Henk A. Dijkstra

Abstract. Observed bimodal distributions of woody cover in western Africa provide evidence that alternative ecosystem states may exist under the same precipitation regimes. In this study, we show that bimodality can also be observed in mean annual shortwave radiation and above-ground biomass, which might closely relate to woody cover due to vegetation–climate interactions. Thus we expect that use of radiation and above-ground biomass enables us to distinguish the two modes of woody cover. However, through conditional histogram analysis, we find that the bimodality of woody cover still can exist under conditions of low mean annual shortwave radiation and low above-ground biomass. It suggests that this specific condition might play a key role in critical transitions between the two modes, while under other conditions no bimodality was found. Based on a land cover map in which anthropogenic land use was removed, six climatic indicators that represent water, energy, climate seasonality and water–radiation coupling are analysed to investigate the coexistence of these indicators with specific land cover types. From this analysis we find that the mean annual precipitation is not sufficient to predict potential land cover change. Indicators of climate seasonality are strongly related to the observed land cover type. However, these indicators cannot predict a stable forest state under the observed climatic conditions, in contrast to observed forest states. A new indicator (the normalized difference of precipitation) successfully expresses the stability of the precipitation regime and can improve the prediction accuracy of forest states. Next we evaluate land cover predictions based on different combinations of climatic indicators. Regions with high potential of land cover transitions are revealed. The results suggest that the tropical forest in the Congo basin may be unstable and shows the possibility of decreasing significantly. An increase in the area covered by savanna and grass is possible, which coincides with the observed regreening of the Sahara.


2021 ◽  
pp. 127092
Author(s):  
Panshak S. Kumdet ◽  
Samuel T. Ivande ◽  
Filibus Danjuma Dami
Keyword(s):  

2021 ◽  
Vol 49 (02) ◽  
pp. 142-147
Author(s):  
Michael Leschnik ◽  
Katja Silbermayr ◽  
Abigail Guija ◽  
Barbara Nell

AbstractCanine African Trypanosomosis (CAT) is a rarely described disease with frequently lethal outcome. A 5-year-old female mongrel dog weighing 22 kg was presented in Austria due to unilateral uveitis, pancytopenia, and anorexia 4 months after return from a trip through Western Africa. Trypanosoma spp. flagellates were detected in a blood smear and identified as Trypanosoma congolense forest type by PCR. Initial treatment with imidocarb and miltefosine led to clinical improvement but only isometamidium chloride hydrochloride applied intramuscularly led to complete eradication of the pathogen from the dog’s blood 4 months later.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
U Laaser ◽  
V Bjegovic-Mikanovic

Abstract Background To reach the targets of SDG3 not more than a decade is left. How do the Low and Middle-Income Countries in Northern Africa - in the immediate neighborhood to Europe - compare to the 15 members of the Economic Community of West African States (ECOWAS), and well-developed European countries around the Baltic Sea (the “Northern Dimension”) incl. Russia? Methods We used quantifiable mortality indicators and targeted reductions until 2030, as published for SDG3.1/2/3 by the United Nations in 2015. To estimate progress or delay we used the methodology of the United Nations Development Program (UNDP) based on the target year 2030, a year of observation, and a year at baseline. For the comparison between Northern Africa/Northern Europe we calculated for indicator 3.3 the Premature Years of Life Lost (PYLL) and for the comparison of Northern/Western Africa the more sensitive indicators 3.1 and 2, the Maternal Mortality Ratio (MMR), the Neonatal Mortality Rate NMR, and the under-five Mortality Rate (<5MR). Results In Northern Africa, only Algerian and Morocco will achieve the 2030 target 3.4 in time i.e., 2.5 and 7 years in advance, whereas Egypt, Libya and Tunisia are in delay Mauretania even by 14.5 years. The countries around the Baltic Sea likely will achieve the targeted reduction before 2030, Estonia on top already 2025, followed by Latvia and Finland in 2026, and the Russian Federation in 2027. Among the 15 West African states, Capo Verde has reached the targets 3.1 and 2 already, followed by Senegal (e.g., 4.0 years in advance for <5MR) and Ghana, whereas Guinea Bissau is positioned at the end with a delay of 4,2 years for MMR. The countries of Northern Africa are on track except for Algeria, with 6.2 years in delay for MMR and Mauretania for all indicators. Conclusions Whereas the European countries are well in advance of the SDG targets, Northern Africa shows a mixed picture and the countries of Western Africa with a few exceptions are in delay. Key messages European countries around the Baltic Sea and Russia are well on track for SDG3, reducing their premature mortality by one third until 2030. Whereas the European countries are well in advance of the SDG targets, Northern Africa shows a mixed picture and the countries of Western Africa with a few exceptions are in delay.


2021 ◽  
Vol 13 (6) ◽  
pp. 1114
Author(s):  
Jianyu Lin ◽  
Yu Zheng ◽  
Xinyong Shen ◽  
Lizhu Xing ◽  
Huizheng Che

The particle linear depolarization ratio (PLDR) and single scatter albedo (SSA) in 1020 nm from the Aerosol Robotic Network (AERONET) level 2.0 dataset was utilized among 52 stations to identify dust and dust dominated aerosols (DD), pollution dominated mixture (PDM), strongly absorbing aerosols (SA) and weakly absorbing aerosols (WA), investigate their spatial and temporal distribution, net radiative forcing and radiative forcing efficiency in global range, and further compare with VIIRS Deep Blue Production. The conclusion about net radiative forcing suggests that the high values of radiative forcing from dust and dust dominated aerosols, pollution dominated mixture both mainly come from western Africa. Strongly absorbing aerosols in South Africa and India contribute greatly to the net radiative forcing and the regions with relative high values of weakly absorbing aerosols are mainly located at East Asia and India. Lastly, the observation of VIIRS Deep Blue satellite monthly averaged products depicts the characteristics about spatial distribution of four kinds of aerosol well, the result from ground-based observation presents great significant to validate the measurements from remote sensing technology.


Zootaxa ◽  
2011 ◽  
Vol 2902 (1) ◽  
pp. 44 ◽  
Author(s):  
CHUNXIA WANG ◽  
SHUQIANG LI

Three new species of the family Telemidae from Côte d’Ivoire and Cameroon are diagnosed, described, and illustrated: i.e., Cangoderces christae sp. nov. and Seychellia jeremyi sp. nov. from Côte d’Ivoire; Cangoderces milani sp. nov. from Cameroon. All types of the new species are deposited in the Nationaal Natuurhistorisch Museum, Leiden, the Netherlands (RMNH).


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