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Journal articles on the topic 'African rivers'
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1
van Gorder, Christian. "Beyond the Rivers of Africa: The Afrocentric Pentecostalism of Mensa Otabil." Pneuma 30, no. 1 (2008): 33–54. http://dx.doi.org/10.1163/157007408x287768.
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AbstractMensa Otabil is an African Pentecostal who has developed an Afrocentric focus as a way of responding to the initiatives and interest that face today's growing African Pentecostal church. Otabil warns African Americans that questions of their relationship with Africa must be addressed. Perhaps Otabil's legacy will be his most immediate role of a motivational speaker and encourager for progress in a part of the world that has been drowned with both internal and external projections of pessimism. What is certain is that Mensa Otabil believes in a Pentecostal faith which is able to speak to Africa's social needs. His conviction is rooted in his conviction that the inherent strength of the great people of Africa is yet to be fully released.
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Patel, Jayanti K. "African Settlements in Gujarat." India Quarterly: A Journal of International Affairs 42, no. 3 (July 1986): 238–46. http://dx.doi.org/10.1177/097492848604200302.
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Indian settlements in Africa are a well-known fact. Studies have been made about their presence and problems. Similarly, there are some African settlements in India. Their presence was first noted by T.H. Esquire as far back as 1926.1 However, so far their presence was noted as a novelty or only in Census Reports. Recently some studies about their social and economic activity have been published. There are some African settlements in Gujarat as Gujarat has had a long tradition of trade with the eastern coast of Africa. The total population of these Africans in Gujarat is nearly five thousand; 3000 of them stay in Saurashtra.2 In the Junagadh District of Saurashtra a small hamlet Jambur, ensconced on the fringe of the Gir Forest between the rivers Saraswati and Karkari, is inhabited entirely (population 500) by Africans.3 Other than this the Africans are settled in mixed areas of Broach, Kutch and Ahmedabad district in Gujarat.
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King, Jackie, and Cate Brown. "Africa's Living Rivers: Managing for Sustainability." Daedalus 150, no. 4 (2021): 240–59. http://dx.doi.org/10.1162/daed_a_01882.
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Abstract Africa's human population is growing rapidly and is set to account for 40 percent of global numbers by 2100. Further development of its inland waters, to enhance water and energy security, is inevitable. Will it follow the development pathway of industrialized countries, often destructive of ecosystems, biodiversity, and river-dependent social structures, or can it chart a new way into the future based on global lessons of equity and sustainability? This essay tracks the global and African growth of the benefits and costs of water resource developments, explores the reasons for the costs, and offers insights on new scientific thinking that can help guide Africa to a more sustainable future.
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da Cunha, L. C., and E. T. Buitenhuis. "Riverine influence on the tropical Atlantic Ocean biogeochemistry." Biogeosciences 10, no. 10 (October 9, 2013): 6357–73. http://dx.doi.org/10.5194/bg-10-6357-2013.
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Abstract. We assess the role of riverine inputs of N, Si, Fe, organic and inorganic C in the tropical Atlantic Ocean using a global ocean biogeochemistry model. We use a standard model scenario and three sensitivity tests to investigate the role of total river nutrient and carbon inputs, as well as the western (South American) and eastern (African) river inputs on the tropical Atlantic Ocean biogeochemistry, between 20° S–20° N and 70° W–20° E. Increased nutrient availability from river inputs in this area (compared to a sensitivity scenario without river nutrient inputs, NO_RIVER) leads to an increase in primary production (PP) and export production (EP), mainly in the coastal ocean area (modeled ocean area with bathymetry <200 m). Model results suggest an enhanced N-fixation by diazotrophs on the tropical Atlantic mainly in open ocean areas. The increased rate of N-fixation in the TODAY scenario is proportional to the increase in PP and EP relative to the NO_RIVER scenario, and may support up to 14% of the coastal ocean export production. Inputs from South American rivers have an impact in coastal PP and EP two times higher than those from African rivers. On the other hand, results suggest that the contribution of African and South American rivers to the total increase in open ocean PP and EP is similar. Considering the amount of delivered nutrients (2–3 times less nutrients and carbon inputs by African rivers) one concludes that African riverine inputs may have a larger impact on the whole tropical Atlantic Ocean biogeochemistry. This is probably due to a combination of nutrient trapping in upwelling areas off the large rivers' outflows and shallow mixed layers in the eastern tropical Atlantic, concomitantly to the differences in delivered nutrient ratios leading to alleviation in limitation conditions, mainly for diatoms. When river inputs are added to the model, we estimate a modest decrease in open ocean sea-air CO2 fluxes (−5.2 Tg C a−1) and an increase in coastal ocean CO2 fluxes, mainly provoked by the remineralization of riverine organic matter delivered by the South American rivers.
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Mudumbi, J. B. N., S. K. O. Ntwampe, F. M. Muganza, and J. O. Okonkwo. "Perfluorooctanoate and perfluorooctane sulfonate in South African river water." Water Science and Technology 69, no. 1 (October 17, 2013): 185–94. http://dx.doi.org/10.2166/wst.2013.566.
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This study examined the prevalence of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in river water samples (n = 56) and suspended solids (n = 5) from three major Western Cape rivers, in South Africa. Solid phase extraction (SPE) followed by liquid chromatography combined with electrospray tandem mass spectrometry (LC-MS/MS) using an analytical method developed in ISO 25101 (2009), PFOS and PFOA concentration in river water and in suspended solids from the rivers was investigated and quantified. From the results, PFOA and PFOS were detected in all the river water samples and were found in concentrations up to 314 and 182 ng/L for Diep River; 390 and 47 ng/L for Salt River; and 146 and 23 ng/L for Eerste River, respectively. In suspended solids, concentrations for PFOS and PFOA were 28 and 26 ng/g for Diep River; 16 and less than limit of detection for Eerste River; and 14 and 5 ng/g for Salt River, respectively. Some of these concentrations are higher than those previously reported in similar studies in various countries, and this suggests there is a cause for concern, in the Western Cape, South Africa, particularly in catchments where river and ground water is drawn for agricultural purposes in the province.
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Hugueny, Bernard, and Didier Paugy. "Unsaturated Fish Communities in African Rivers." American Naturalist 146, no. 1 (July 1995): 162–69. http://dx.doi.org/10.1086/285792.
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Hamann, Yvonne, Werner Ehrmann, Gerhard Schmiedl, and Tanja Kuhnt. "Modern and late Quaternary clay mineral distribution in the area of the SE Mediterranean Sea." Quaternary Research 71, no. 3 (May 2009): 453–64. http://dx.doi.org/10.1016/j.yqres.2009.01.001.
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AbstractThe present-day clay mineral distribution in the southeastern Levantine Sea and its borderlands reveals a complex pattern of different sources and distribution paths. Smectite dominates the suspended load of the Nile River and of rivers in the Near East. Illite sources are dust-bearing winds from the Sahara and southwestern Europe. Kaolinite is prevalent in rivers of the Sinai, in Egyptian wadis, and in Saharan dust. A high-resolution sediment core from the southeastern Levantine Sea spanning the last 27 ka shows that all these sources contributed during the late Quaternary and that the Nile River played a very important role in the supply of clay. Nile influence was reduced during the glacial period but was higher during the African Humid Period. In contrast to the sharp beginning and end of the African Humid Period recorded in West African records (15 and 5.5 ka), our data show a more transitional pattern and slightly lower Nile River discharge rates not starting until 4 ka. The similarity of the smectite concentrations with fluctuations in sea-surface temperatures of the tropical western Indian Ocean indicates a close relationship between the Indian Ocean climate system and the discharge of the Nile River.
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Kofron, Christopher P. "Status and habitats of the three African crocodiles in Liberia." Journal of Tropical Ecology 8, no. 3 (August 1992): 265–73. http://dx.doi.org/10.1017/s0266467400006490.
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ABSTRACTA representative sample of waterways in Liberia was surveyed for crocodiles, and all three species of African crocodiles were observed. Contrary to previous reports, only Nile crocodiles inhabit the Monrovia mangrove swamps and brackish-water mouths of rivers; there are no slendersnouted or dwarf crocodiles in these habitats. There is partitioning of habitats among the three species in Liberia: Nile crocodiles in mangrove swamps and river mouths (brackish water); slendersnouted crocodiles in rivers through rain forest (freshwater); and dwarf crocodiles in small streams through rain forest (freshwater), some entering the adjacent river. Dwarf crocodiles utilize burrows in the stream banks.Nowhere are crocodiles abundant, and there is an apparent absence of adults. Although 40% of Liberia is forested, deforestation is occurring rapidly by foreign timber companies and slash-and-burn agriculture practised by the largely rural population. Hunting with firearms, although illegal, is widespread, both for subsistence and commercially, without concern for depletion. Mangrove ecosystems near human population centres are being destroyed. The combination of the above factors has apparently depleted the crocodile populations in Liberia.
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Brautigam, Deborah, and Jyhjong Hwang. "Great walls over African rivers: Chinese engagement in African hydropower projects." Development Policy Review 37, no. 3 (February 7, 2019): 313–30. http://dx.doi.org/10.1111/dpr.12350.
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Lezine, Anne-Marie, and Jean-Pierre Cazet. "High-Resolution Pollen record from Core KW31, Gulf of Guinea, Documents the History of the Lowland Forests of West Equatorial Africa since 40,000 yr ago." Quaternary Research 64, no. 3 (November 2005): 432–43. http://dx.doi.org/10.1016/j.yqres.2005.08.007.
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AbstractPollen data from core KW31 recovered off the mouth of the Niger River (3°31′1N–05°34ʺ1E; 1181 m water depth) provide an exceptional record of vegetation changes in the West African lowlands between 40,000 and 3500 cal yr B.P. The highly diverse microflora testify for the permanency of rain and secondary forests in the Niger river catchment, at least as gallery formations along rivers, during the last glacial period when dry conditions occurred in relation to enhanced trade-wind circulation. The direct consequence of the post-glacial warming and the correlative increase in monsoon fluxes over West Africa was the increase in forest diversity and the expansion of rain and secondary forests on the nearby continent. Comparison between KW31 pollen record and continental pollen data from 5°S to 25°N allows the evaluation of migration rates of tropical forest populations throughout North West Africa at the beginning of the Holocene and the vegetation response to the shift toward aridity recorded widely at the end of the African Humid Period around 4000 cal yr B.P.
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Zeisler-Vralsted, Dorothy. "African Americans and the Mississippi River: Race, history and the environment." Thesis Eleven 150, no. 1 (January 7, 2019): 81–101. http://dx.doi.org/10.1177/0725513618822010.
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Long touted in literary and historical works, the Mississippi River remains an iconic presence in the American landscape. Whether referred to as ‘Old Man River’ or the ‘Big Muddy,’ the Mississippi River represents imageries ranging from pastoral and Acadian to turbulent and unpredictable. But these imageries – revealed through the cultural production of artists, writers and even filmmakers – did not adequately reflect the experiences of everyone living and working along the river. The African-American community and its relationship to the Mississippi River down the ages is occluded by these discourses. In focusing on this alternate history, namely the African-American experience with the Mississippi River, the overarching framework of this paper will consist of three lenses on the river as: refuge, labor, and cultural icon. From the moment of their arrival, the intersection of their lives with the Mississippi River reveals a history where the river offers freedom, oppression, escape, sustenance, renewal, disease and displacement. From this largely unexplored perspective, distinctions of race and class are exposed and reinforced. Although rivers have long been included in the historical record, whether through a geographical, spiritual, aesthetic or recreational perspective, the juncture where human lives intersect with rivers, constructing memory and identity, remains overlooked despite a plethora of cultural artifacts such as song, prose and poetry that distinguish experiences. These cultural artifacts, in turn, differentiate reciprocal relationships with the river based on race and class. For the African-American community, the Mississippi River alternated between liberator and oppressor, informing the social construct of an identity that was at times lamented, celebrated, demeaned and feared. But how did these linkages with the river not only influence a distinct collective memory but also nurture a culture with certain understandings and perspectives about the river? And if so, what have been their ramifications? Through an examination of folklore, song and first-person accounts, these questions will be addressed as multiple narratives persist, offering a history that makes more explicit the distinctive experiences of the African-American communities in their engagement with the Mississippi River.
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Rabelo, Leandro Bonesi, and Lucy Satiko Hashimoto Soares. "FEEDING INTERACTION OF THE NON-NATIVE AFRICAN CATFISH (Clarias gariepinus BURCHELL, 1822) IN ITANHÉM RIVER ESTUARY, BAHIA, BRAZIL." Brazilian Journal of Oceanography 62, no. 3 (September 2014): 179–86. http://dx.doi.org/10.1590/s1679-87592014051406203.
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A total of 214 stomachs of Clarias gariepinus, Centropomus undecimalis and C. parallelus from the Itanhém and Caravelas Rivers, northeastern Brazil, were analyzed to investigate the impact of the non-native species Clarias gariepinus on the Itanhém River food web as compared to that of the adjacent Caravelas River, where this species has not been registered. In Itanhém River, shrimp was the most important food for C. gariepinus, and Teleostei for C. parallelus. In the Caravelas River, Brachyura was the main food item for C. parallelus, and Teleostei for C. undecimalis. There was no food overlap between the species within or between rivers. There is no evidence, in the results of this study, of changes in the diet of the Centropomus parallelus due to the presence of the non-native species.
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Potgieter, Natasha, Simbarashe Karambwe, Lutendo Sylvia Mudau, Tobias Barnard, and Afsatou Traore. "Human Enteric Pathogens in Eight Rivers Used as Rural Household Drinking Water Sources in the Northern Region of South Africa." International Journal of Environmental Research and Public Health 17, no. 6 (March 20, 2020): 2079. http://dx.doi.org/10.3390/ijerph17062079.
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People living in rural areas still rely on the use of environmental water that is contaminated by human and animal activities. This study assessed the occurrence of human enteric pathogens in rivers that are used by rural communities Vhembe District of South Africa as a source of drinking water covering two seasons (winter and summer) over a one-year period. Water quality was assessed using physico characteristics and indicator organisms (total coliforms, E. coli, Clostridium perfringens). Pathogens tested included bacteria (Pathogenic E. coli, Salmonella-, Shigella- and Vibrio spp.), protozoa (Cryptosporidium- and Giardia spp.), and enteric viruses (Rota-, Noro-, Entero-, and Adenoviruses) while using published molecular protocols. The results showed that the indicator bacteria counts exceeded South African drinking water quality guideline limits and pathogenic E. coli was detected in the samples. No Shigella spp. were isolated, while Vibrio spp. and Salmonella spp. were present; parasites were detected in four rivers and Enteric viruses were predominantly detected in the winter season. The results indicated the poor condition of water and the potential health risks to consumers highlighting the need for implementing river catchment management strategies for continued sustainability in these rivers.
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Ingenbleek, Paul T. M. "The Biogeographical Foundations of African Marketing Systems." Journal of Macromarketing 40, no. 1 (January 8, 2020): 73–87. http://dx.doi.org/10.1177/0276146719896393.
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The marketing literature is showing an increasing interest in Africa. This article addresses the contextual macro-level characteristics that such studies have in common, and traces the typical characteristics of African marketing systems back to their ultimately biogeographical foundations. These foundations include the north-south orientation of the main continental axis, the low presence of geological boundaries such as mountains and rivers, and Africa as the “cradle of mankind.” Through their evolutionary consequences, these factors evolved into the aggregate marketing system traits typical to Africa, which include the existence of multi-level markets connected by traders, a sharp distinction between the formal and informal sectors, and an overwhelming presence of micro-entrepreneurs and smallholder farmers. This analysis generates new insights into, among others, the role of biogeographical factors in marketing systems theory and the potential sources of competitive advantage and disadvantage for the endogenous African firms inherent to the system.
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Chigamba, Gladys, Moses Limuwa, and Emmanuel Kaunda. "Does Paying for Aquatic Resources Matter? A Case of an African Riverine Ecosystem." Sustainability 13, no. 8 (April 9, 2021): 4177. http://dx.doi.org/10.3390/su13084177.
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Valuation of environmental goods and services has an important role to play in the protection and conservation of riverine resources. However, the literature shows a dearth of information regarding factors that influence people’s willingness to pay (WTP) for riverine resources. This research study was undertaken to find out key factors that affect the willingness of people to pay for the conservation of aquatic resources in the lower section of the Linthipe River in Malawi. Data was collected through household interviews, focus group discussions, key informant interviews, and contingent valuation (CV) surveys. The study noted that communities were willing to offer $3.51 per year for the conservation of aquatic resources in the river. This study established that the people’s WTP is a function of education level, household usage of the goods and services, community support in the management of the resources, household income, and distance of the household from the river ecosystem. The study further discovered that the pay-out level of the users along the Linthipe River was driven by household usage of resources from the river, period of stay in the area, and level of household income. Our recommendation is that government and development partners should popularize the important role played by rivers and streams to surrounding communities and beyond to appeal for more support from users. The authorities must further empower the communities along the rivers and streams to sustainably manage the aquatic resources for the continued appreciation of aquatic resources by future generations.
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Fatah-Black, Karwan. "Slaves and Sailors on Suriname's Rivers." Itinerario 36, no. 3 (December 2012): 61–82. http://dx.doi.org/10.1017/s0165115313000053.
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On transatlantic slave ships the Africans were predominantly there as cargo, while Europeans worked the deadly job of sailing and securing the vessel. On the plantations the roles changed, and the slaves were transformed into a workforce. European sailors and African slaves in the Atlantic world mostly encountered each other aboard slave ships as captive and captor. Once the enslaved arrived on the plantations new hierarchies and divisions of labour between slave and free suited to the particular working environment were introduced. Hierarchies of status, rank and colour were fundamental to the harsh and isolated working environments of the ship and the plantation. The directors of Surinamese plantations shielded themselves from the wrath of their enslaved by hiring sailors, soldiers or other white ruffians to act as blankofficier (white officer). These men formed a flexible workforce that could be laid off in case tensions on plantations rose. Below the white officers there were non-white slave officers, basjas, managing the daily operations on the plantations. The bomba on board slave ships played a similar role.
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Luiselli, L., G. C. Akani, N. Ebere, F. M. Angelici, G. Amori, and E. Politano. "Macro-habitat preferences by the African manatee and crocodiles – ecological and conservation implications." Web Ecology 12, no. 1 (July 4, 2012): 39–48. http://dx.doi.org/10.5194/we-12-39-2012.
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Abstract. African manatees (Trichechus senegalensis) and crocodiles are threatened species in parts of their range. In West Africa, crocodiles may constitute the main predators for manatees apart from humans. Here, we explore the macro-habitat selection of manatees and two species of crocodiles (West African crocodiles Crocodylus suchus and dwarf crocodile Osteolaemus tetraspis) in the Niger Delta (Nigeria), testing the hypotheses that (i) manatees may avoid crocodiles in order to minimize risks of predation, and (ii) the two crocodile species do compete. The study was carried out between 1994 and 2010 with a suite of different field techniques. We observed that the main macro-habitat types were freshwater rivers and coastal lagoons for manatees, mangroves for West African crocodiles, and rivers and creeks for dwarf crocodiles, with (i) the three species differing significantly in terms of their macro-habitat type selection, and (ii) significant seasonal influence on habitat selection of each species. Null models for niche overlap showed a significantly lower overlap in macro-habitat type use between manatee and crocodiles, whereas the two crocodiles were relatively similar. Null model analyses did not indicate any competitive interactions between crocodiles. On the other hand, manatees avoided macro-habitats where crocodiles, and especially West African crocodiles, are abundant.
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MCKITTRICK, MEREDITH. "MAKING RAIN, MAKING MAPS: COMPETING GEOGRAPHIES OF WATER AND POWER IN SOUTHWESTERN AFRICA." Journal of African History 58, no. 2 (June 7, 2017): 187–212. http://dx.doi.org/10.1017/s0021853717000032.
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AbstractThis article explores the alchemy whereby ritual and political worlds invisible to Europeans were rendered visible on European maps. It begins with a puzzle: representations of southwestern Africa's rivers on those maps bear little resemblance to physical reality as the cartographers would have understood it. Using GIS technology to georeference a series of maps and highlight the placement of rivers on them illustrates the convergence of cartographers’ representations and regional political cosmologies linking power to control over water. Travelers’ accounts and colonial archives illuminate how knowledge was produced and why African ideas about geography were inadvertently embedded in those maps well into the twentieth century. This method opens a window into otherwise-obscured African intellectual history and demonstrates that even something as apparently and unambiguously ‘European’ as modern mapping was the result of on-the-ground negotiations well into the colonial period.
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Cotrim da Cunha, L., and E. T. Buitenhuis. "Riverine influence on the tropical Atlantic Ocean biogeochemistry." Biogeosciences Discussions 9, no. 2 (February 17, 2012): 1945–69. http://dx.doi.org/10.5194/bgd-9-1945-2012.
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Abstract. We assess the role of riverine inputs of N, Si, Fe, organic and inorganic C in the tropical Atlantic Ocean using a global ocean biogeochemistry model. We use two sensitivity tests to investigate the role of the western (South American Rivers) and eastern (African Rivers) riverine nutrient inputs on the tropical Atlantic Ocean biogeochemistry (between 20° S–20° N and 70° W–20°). Increased nutrient availability from river inputs in this area (compared to an extreme scenario with no river nutrients) leads to an increase in 14 % (0.7 Pg C a−1) in open ocean primary production (PP), and 21 % (0.2 Pg C a−1) in coastal ocean PP. We estimate very modest increases in open and coastal ocean export production and sea-air CO2 fluxes. Results suggest that in the tropical Atlantic Ocean, the large riverine nutrient inputs on the western side have a larger impact on primary production and sea-air CO2 exchanges. On the other hand, African river inputs, although smaller than South American inputs, have larger impact on the coastal and open tropical Atlantic Ocean export production. This is probably due to a combination of nutrient trapping in upwelling areas off the Congo River outflow, and differences in delivered nutrient ratios leading to alleviation in limitation conditions mainly for diatoms.
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Mark, Peter. "Constructing Identity: Sixteenth- and Seventeenth-Century Architecture in the Gambia-Geba Region and the Articulation of Luso-African Ethnicity." History in Africa 22 (January 1995): 307–27. http://dx.doi.org/10.2307/3171919.
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The precolonial architectural history of the northern Upper Guinea coast from the Gambia to the Geba rivers has yet to be studied in depth. Yet this region, the first to be visited and described by European travelers in the fifteenth and early sixteenth centuries, is among the best-documented parts of sub-Saharan Africa for the four centuries of precolonial African-European contact. The establishment of communities of Luso-African traders in the sixteenth and seventeenth century makes the Gambia-Casamance-Bissau area important to the study of early sustained cultural interaction between Europeans and West Africans.One result of the establishment of Portuguese and Luso-African trading communities was the development of a distinctive style of architecture, suited to the climate and making use of locally-available building materials. The history of the trade itself has been extensively studied by George Brooks. His work, along with that of Jean Boulègue, provides a firm foundation for the study of local architecture and living space. It is not my intention to rewrite these excellent sources, although much of my material is drawn from the same primary documents they have used, and although, in presenting the historical context from which seventeenth-century coastal architecture developed, I necessarily cover some ground that Brooks has already trod.In addition to the history of building styles, several related questions that are highly significant to the history of European-African cultural interaction need to be addressed. These questions include: what were the respective roles of Africans, Europeans, and Luso-Africans in the development of a distinctive architectural style? Is it possible to discern the influence of evolving Luso-African construction on local African architecture? And of local building styles on Afro-European construction? In other words, to what extent does architecture reflect mutual, two-way interaction between European and African society?
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SAMRAOUI, BOUDJÉMA, ZINEB BOUHALA, ANTONIO RUIZ GARCIA, JOAQUÍN MÁRQUEZ-RODRÍGUEZ, MANUEL FERRERAS-ROMERO, HAMED A. EL-SEREHY, and FARRAH SAMRAOUI. "Trichoptera and Plecoptera of the Seybouse River, northeast Algeria: Distribution, phenology and new records." Zootaxa 4845, no. 4 (September 4, 2020): 552–64. http://dx.doi.org/10.11646/zootaxa.4845.4.5.
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The stoneflies and caddisflies of North Africa are still poorly known as vast areas of Algeria have yet to be investigated. A survey of the macroinvertebrates of the Seybouse River, northeast Algeria, was carried out from July 2014 to December 2016. Three species of stoneflies (Capnopsis schilleri, Capnioneura petitpierreae, and Tyrrhenoleuctra tangerina) and five taxa of caddisflies (Mesophylax aspersus, Hydropsyche maroccana, H. resmineda, H. artax/lobata, and H. gr. pellucidula) were identified. All taxa are new records to the Seybouse River and seven of them are new to northeastern Algeria. A multivariate analysis indicated that the Hydropsychidae exhibited a clear longitudinal gradient along the Seybouse River while Mesophylax aspersus seemed adapted to species-poor, intermittent streams. Further investigations of the stoneflies and caddisflies may inform conservation efforts and will prove useful to monitor the Seybouse River and similarly threatened North African rivers and streams.
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DeSombre, Elizabeth R. "Learning to Manage Global Environmental Risks, vols. 1 & 2. By The Social Learning Group. Edited by William C. Clark, Nancy Dickson, Jill Jäger, and Josee van Eijndhoven. Cambridge, MA: MIT Press, 2001. Vol. 1: $75.00 cloth, $30.00 paper. Vol. 2: $60.00 cloth, $27.00 paper." American Political Science Review 96, no. 3 (September 2002): 681–82. http://dx.doi.org/10.1017/s0003055402940360.
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I have a colleague who collects maps of Africa that demonstrate a specific phenomenon: the developed world's unlearning of African geography. Across the centuries, the maps seem to show that mapmakers know less about the geography of the African continent—particularly the internal parts—than previously was the case. Rivers change direction; mountain ranges disappear. This unlearning, my colleague argues, comes from notions about the acceptability of sources of information previously used. These maps show the social nature of “learning,” the idea that while in many cases there may be actual answers (after all, African geography exists), what information you look for, and from whom, determines how you will view the information you get, and ultimately what you will do with it.
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Elias, Julius D., Jasper N. Ijumba, Yunus D. Mgaya, and Florence A. Mamboya. "Study on Freshwater Macroinvertebrates of Some Tanzanian Rivers as a Basis for Developing Biomonitoring Index for Assessing Pollution in Tropical African Regions." Journal of Ecosystems 2014 (October 13, 2014): 1–8. http://dx.doi.org/10.1155/2014/985389.
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Macroinvertebrates and physicochemical parameters were assessed at 15 sites along five rivers in Kilimanjaro region, Tanzania, with the aim of understanding their ecological status and setting a base to the development of a biological index for tropical regions. Investigated rivers that occur within Pangani basin include Karanga, Rau, Lumbanga, Sere, and Umbwe. Sampling sites were categorized according to the level of water and habitat quality as follows: reference or least impacted (4 sites), moderately impacted (5 sites), and highly impacted (6 sites) sites. A total of 12,527 macroinvertebrates belonging to 13 orders and 48 families were recorded. The highest total abundance of 4,110 individuals per m2 was found in Karanga river, while Umbwe river had the lowest with 1,203 individuals per m2. Chironomidae was the most abundant family (2,588 individuals per m2) and the least were Hydridae and Thiaridae, each having 5 individuals per m2. High numbers of taxa were noted among the orders: Ephemeroptera (8), Odonata (8), Diptera (7), and Trichoptera (6). In conclusion, orders with greater diversity of macroinvertebrate families offer a wide range of tolerance to pollution and, thus can potentially be used to develop a biomonitoring index for evaluating pollution in tropical African rivers.
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Patience, Zisadza-Gandiwa, Chiganze Samuel, Chirombe Paul, Mashapa Clayton, Muboko Never, and Gandiwa Edson. "Abundance and Distribution of African Fish Eagles along Major Rivers in Gonarezhou National Park, Zimbabwe." Greener Journal of Biological Sciences 3, no. 9 (November 17, 2013): 336–41. http://dx.doi.org/10.15580/gjbs.2013.9.111213952.
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Mark, Peter. "“Portuguese” Architecture and Luso-African Identity in Senegambia and Guinea, 1730–1890." History in Africa 23 (January 1996): 179–96. http://dx.doi.org/10.2307/3171940.
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Along the West African coast and in the immediate hinterland from the Gambia River to Sierra Leone in the eighteenth and the first half of the nineteenth century, a region of extensive long-distance trade, the buildings people lived in, as well as the physical layout of their communities, served as important elements in the articulation of their cultural identity. At the same time, architecture reflected contact between the various populations of the region. These groups included a small number of Portuguese and a somewhat larger population of several thousand Luso-Africans, whose commercial role as traders, declining by the late eighteenth century, was limited essentially to the navigable lower reaches of coastal rivers and waterways.These Luso-Africans, faced by Europeans who contested their efforts to define themselves as a group, were gradually marginalized and ultimately subsumed into the neighboring coastal populations, leaving only traces of their distinctive culture. Among the elements that comprised the Luso-African cultural legacy were houses built in “Portuguese” style: rectangular structures with whitewashed exteriors and a vestibule or a porch. From the sixteenth to the eighteenth centuries, these houses helped to define the Luso-African community.The local African populations of West Atlantic-speakers (Floups, Bagnuns, Bijogos, and Papels) and, further down the coast, Susus, Temnes and Bulloms, were for the most part organized into small-scale, decentralized societies. Mande-speaking peoples inhabited the small states of the lower Gambia and the more important state of Kaabu in Guinea-Bissau; they, together with ‘juula’ merchants, comprised the western outriders of the Mande diaspora. Further east, in the newly-established Islamic state of Fuuta Jaloo (Futa Jalon), lived the Fulbe.
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Selemani, Juma R., Jing Zhang, Ying Wu, Alfred N. N. Muzuka, Karoli N. Njau, Guosen Zhang, Maureen K. Mzuza, Arafa Maggid, Miao Zhang, and Lijun Qi. "Distribution of organic carbon: possible causes and impacts in the Pangani River Basin ecosystem, Tanzania." Environmental Chemistry 15, no. 3 (2018): 137. http://dx.doi.org/10.1071/en17185.
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Environmental contextUnderstanding the sources of organic carbon and its spatial and seasonal variation is essential for implementing measures to control water pollution. There is, however, only limited information about organic carbon in east African rivers. This study reports the distribution of dissolved and particulate organic carbon in the Pangani River Basin, using isotopes to trace sources of carbon to the basin and its flux to the Indian Ocean. AbstractThere is limited information on organic carbon in African rivers, especially from the eastern side. Here, we report distribution and impacts of total suspended matter (TSM), and dissolved and particulate organic carbon (DOC & POC) in the Pangani River Basin (PRB) ecosystem together with their fluxes to the Indian Ocean. δ13C was also used to trace sources of carbon in the basin. Results showed that the basin is supplied with carbon from allochthonous sources dominated by C3 plants, with higher levels of TSM and DOC in the wet season than in the dry season. Several factors, including altitude, temperature, rainfall, lithology and anthropogenic activities, have a significant influence on the seasonal and spatial distribution of organic carbon in the basin. High discharge in the wet season mobilised terrestrial organic carbon to elevate concentrations of DOC, POC and TSM. Mean concentrations of DOC, dissolved inorganic carbon (DIC), POC and TSM in PRB were in ranges comparable to that in other tropical rivers but their fluxes were lower than in most tropical rivers around the world. Diverting water from the river for irrigation and hydroelectric power production was one of the factors that reduced the flux of carbon. Observed hypoxic conditions in the reservoir indicates that the quality of water for human and aquatic ecosystem health is possibly threatened by a high level of organic carbon; furthermore, the trends of increasing population, deforestation, temperature and rainfall will likely increase the concentration of organic carbon in the future. Better management of waste, afforestation and reforestation are recommended to restore degraded natural forest, so as to reduce uptake of organic carbon from the terrestrial environment.
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Peters, Penelope. "Deep Rivers: Selected Songs of Florence Price and Margaret Bonds." Canadian University Music Review 16, no. 1 (March 1, 2013): 74–95. http://dx.doi.org/10.7202/1014417ar.
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This essay examines the songs of two African-American women, Florence Price (1888–1953) and Margaret Bonds (1913–72), who embarked upon their compositional studies and careers only a couple of generations after the emancipation. Both discovered in the poetry of Langston Hughes (1902–67) the means for reconciling the musical traditions of their African-American heritage with those of their European training. Through detailed analysis of the textual and musical symbolism in Price's Song to a Dark Virgin and Bonds's The Negro Speaks of Rivers and Three Dream Portraits, the author demonstrates the influence of spirituals ("plantation songs"), blues, and jazz and reveals how these African-American idioms are integrated with the melodic and harmonic idioms from the early twentieth-century European tradition.
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Kondakov, Alexander V., Ekaterina S. Konopleva, Abiona J. Adesanya, Yulia V. Bespalaya, Jean J. Braun, Mikhail Y. Gofarov, Artem A. Lyubas, et al. "The global freshwater bivalve checklist’s extension: Freshwater occurrences and phylogenetic position of Galatea clams from West Africa (Venerida: Donacidae)." Ecologica Montenegrina 35 (October 25, 2020): 144–58. http://dx.doi.org/10.37828/em.2020.35.12.
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The bivalve genus Galatea Bruguière, 1797 (Venerida: Donacidae) was thought to contain exclusively brackish-water clams, the ranges of which are confined to estuaries and lower tidal parts of large rivers in West Africa. This genus was therefore included to the global freshwater bivalve checklists (Bogan 2013; Graf 2013) as a largely estuarine group. Conversely, a review of published data alongside our field surveys indicate that at least three populations of Galatea spp. largely occur in freshwater environment, i.e. those from the Sanaga (Cameroon), Niger (Nigeria), and Volta (Ghana) rivers. The systematic placement of these populations is unclear, as are the taxonomic status and validity of numerous nominal taxa described in this genus from a variety of localities throughout the Atlantic Coast of Africa (Angola to Senegal). We tentatively assign the populations from Niger and Volta to Galatea paradoxa (Born, 1778), while the Sanaga’s population is considered here as Galatea schwabi (Clench, 1929). However, these taxa do not share clear morphological differences and may belong to a single widespread species. In this study, we present the first DNA sequence data for a Galatea member, i.e. G. schwabi. Our COI phylogeny supports its placement within the family Donacidae suggesting sister relationships between Galatea and Donax Linnaeus, 1758. Most Galatea populations play a vital role for local riparian communities in West Africa as an intensively exploited food source. Furthermore, the clams are heavily threaten by anthropogenic impacts such as dam construction, riverbed substrate mining, and river pollution. The fishing loads and habitat degradation altogether lead to the rapid decreasing of Galatea populations in several water bodies, e.g. the Volta River in Ghana. It is impossible to develop conservation and management plans for these clams due to the lack of reliable species-level taxonomic concept of the genus. It is clear that the Galatea taxonomy and ecology need a thorough revision in the future based on DNA sequences of newly collected samples from all West African rivers, in which these remarkable clams occur.
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Juízo, Dinis, and Peder Hjorth. "Application of a district management approach to Southern African river basin systems: the case of the Umbeluzi, Incomati and Maputo river basins." Water Policy 11, no. 6 (October 1, 2009): 719–30. http://dx.doi.org/10.2166/wp.2009.301.
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In recent years, the ‘river basin as a management unit’ approach has been adopted as a solution to water management. The situation between Swaziland, Mozambique and South Africa regarding managing the water resources of the Incomati, Maputo, and Umbeluzi shared river basins is an interesting case that might need a different approach. These rivers flow downstream to the Maputo estuary where their waters are needed for urban water supply (Maputo city) and fresh water pulses for the estuary. The Incomati and Umbeluzi are heavily committed upstream while the Maputo appears still to have a relative abundance of untapped water resources. At basin level, the three countries fail to reach a consensus on the best strategies to accommodate multiple demands, particularly in the downstream area. The IncoMaputo agreement that was concluded by the three governments is unique in that it comprises two basins (Maputo and Incomati), allowing a multi-basin approach to the problem. However, the Umbeluzi was left out of the agreement. This paper discusses the possible benefits of a multi-basin approach to water resources for the three rivers discharging into Espírito Santo Estuary in Maputo. Using the provisions set out in the European Union Water Framework Directive (WFD) it is found that the three rivers of this study may well be suitable for implementing the District Water Management approach as proposed in the WFD.
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Archibald, C. G. M., and J. C. Taylor. "The assessment of diffuse pollution from acid-mine drainage using an updated and revised diatom assessment procedure as an added-value bio-monitoring tool." Water Science and Technology 55, no. 3 (February 1, 2007): 151–60. http://dx.doi.org/10.2166/wst.2007.083.
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Three data sources (physico-chemistry, bio-monitoring and eco-toxicology) are currently used in South Africa to establish environmental water quality conditions. Environmental water quality in turn is key information required for the “ecological reserve determination” of river reaches. Bio-monitoring in South Africa has been limited in recent times mostly to the use of the SASS procedure which relies on invertebrates only. This paper describes the re-introduction of a diatom-based water quality assessment as an added-value bio-monitoring tool. A specific example is discussed citing the response of diatom assemblages to diffuse pollution from acid mine drainage and how effective diatoms are as indicators of ecological integrity and river recovery measured downstream of the area of impact. The advantages of applying this bio-monitoring technique over other biological measures are presented in the context of technological advances in rapid image processing, species identification and software applications of diatom-based water quality indices. The valuable records of the diatom assemblages of the past, held in the South African Diatom Collection at the CSIR (KwaZulu-Natal), can now be accessed and interpreted as historical environmental water quality reference points for several rivers in South Africa.
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Igbinosa, Isoken H., Vincent N. Chigor, Etinosa O. Igbinosa, Lawrence C. Obi, and Anthony I. Okoh. "Antibiogram, Adhesive Characteristics, and Incidence of Class 1 Integron inAeromonasSpecies Isolated from Two South African Rivers." BioMed Research International 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/127570.
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Aeromonasspecies are well distributed in freshwater environments, and their natural susceptibility to antimicrobials renders them interesting candidates for the survey of antimicrobial resistance in freshwater milieu. Water samples were collected from Kat and Tyume rivers in the Eastern Cape province of South Africa, and a total of 45 isolates identified asAeromonasspecies were recovered from the two rivers. AllAeromonasisolates were resistant to oxacillin, penicillin, clindamycin, cephalothin, vancomycin, and rifamycin, while appreciable susceptibilities (89.3 : 94.1%, 82.1 : 94.1%, 85.7 : 88.2%, and 92.9 : 88.2%) were observed against ciprofloxacin, chloramphenicol, nitrofurantoin, and gentamicin from Kat and Tyume rivers, respectively. Multiple antibiotic resistance (MAR) indices ranged from 0.016 to 0.044 for the two rivers. Class 1 integron was detected in about 20% of the isolates, and all the isolates except one showed ability to produce biofilmin vitroas weak producers (53.33%), moderate producers (15.56%), and strong producers (28.9%). This investigation provides a baseline data on antibiotic resistance as well as the adhesive characteristics ofAeromonasisolates from Tyume and Kat rivers in the Eastern Cape province of South Africa.
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Upstill-Goddard, Robert C., Matthew E. Salter, Paul J. Mann, Jonathan Barnes, John Poulsen, Bienvenu Dinga, Gregory J. Fiske, and Robert M. Holmes. "The riverine source of CH<sub>4</sub> and N<sub>2</sub>O from the Republic of Congo, western Congo Basin." Biogeosciences 14, no. 9 (May 5, 2017): 2267–81. http://dx.doi.org/10.5194/bg-14-2267-2017.
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Abstract. We discuss concentrations of dissolved CH4, N2O, O2, NO3− and NH4+, and emission fluxes of CH4 and N2O for river sites in the western Congo Basin, Republic of Congo (ROC). Savannah, swamp forest and tropical forest samples were collected from the Congo main stem and seven of its tributaries during November 2010 (41 samples; wet season) and August 2011 (25 samples; dry season; CH4 and N2O only). Dissolved inorganic nitrogen (DIN: NH4++ NO3−; wet season) was dominated by NO3− (63 ± 19 % of DIN). Total DIN concentrations (1.5–45.3 µmol L−1) were consistent with the near absence of agricultural, domestic and industrial sources for all three land types. Dissolved O2 (wet season) was mostly undersaturated in swamp forest (36 ± 29 %) and tropical forest (77 ± 36 %) rivers but predominantly supersaturated in savannah rivers (100 ± 17 %). The dissolved concentrations of CH4 and N2O were within the range of values reported earlier for sub-Saharan African rivers. Dissolved CH4 was found to be supersaturated (11.2–9553 nmol L−1; 440–354 444 %), whereas N2O ranged from strong undersaturation to supersaturation (3.2–20.6 nmol L−1; 47–205 %). Evidently, rivers of the ROC are persistent local sources of CH4 and can be minor sources or sinks for N2O. During the dry season the mean and range of CH4 and N2O concentrations were quite similar for the three land types. Wet and dry season mean concentrations and ranges were not significant for N2O for any land type or for CH4 in savannah rivers. The latter observation is consistent with seasonal buffering of river discharge by an underlying sandstone aquifer. Significantly higher wet season CH4 concentrations in swamp and forest rivers suggest that CH4 can be derived from floating macrophytes during flooding and/or enhanced methanogenesis in adjacent flooded soils. Swamp rivers also exhibited both low (47 %) and high (205 %) N2O saturation but wet season values were overall significantly lower than in either tropical forest or savannah rivers, which were always supersaturated (103–266 %) and for which the overall means and ranges of N2O were not significantly different. In swamp and forest rivers O2 saturation co-varied inversely with CH4 saturation (log %) and positively with % N2O. A significant positive correlation between N2O and O2 saturation in swamp rivers was coincident with strong N2O and O2 undersaturation, indicating N2O consumption during denitrification in the sediments. In savannah rivers persistent N2O supersaturation and a negative correlation between N2O and O2 suggest N2O production mainly by nitrification. This is consistent with a stronger correlation between N2O and NH4+ than between N2O and NO3−. Our ranges of values for CH4 and N2O emission fluxes (33–48 705 µmol CH4 m−2 d−1; 1–67 µmol N2O m−2 d−1) are within the ranges previously estimated for sub-Saharan African rivers but they include uncertainties deriving from our use of basin-wide values for CH4 and N2O gas transfer velocities. Even so, because we did not account for any contribution from ebullition, which is quite likely for CH4 (at least 20 %), we consider our emission fluxes for CH4 to be conservative.
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Oi Edia, Edia, Sebastien Brosse, Allassane Ouattara, Germain Gourene, Peter Winterton, and Sithan Lek-Ang. "Aquatic Insect Assemblage Patterns in Four West-African Coastal Rivers." Journal of Biological Sciences 7, no. 7 (September 15, 2007): 1130–38. http://dx.doi.org/10.3923/jbs.2007.1130.1138.
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Schwarzer, Julia, Ernst Roelof Swartz, Emmanuel Vreven, Jos Snoeks, Fenton Peter David Cotterill, Bernhard Misof, and Ulrich Kurt Schliewen. "Repeated trans-watershed hybridization among haplochromine cichlids (Cichlidae) was triggered by Neogene landscape evolution." Proceedings of the Royal Society B: Biological Sciences 279, no. 1746 (September 5, 2012): 4389–98. http://dx.doi.org/10.1098/rspb.2012.1667.
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The megadiverse haplochromine cichlid radiations of the East African lakes, famous examples of explosive speciation and adaptive radiation, are according to recent studies, introgressed by different riverine lineages. This study is based on the first comprehensive mitochondrial and nuclear DNA dataset from extensive sampling of riverine haplochromine cichlids. It includes species from the lower River Congo and Angolan (River Kwanza) drainages. Reconstruction of phylogenetic hypotheses revealed the paradox of clearly discordant phylogenetic signals. Closely related mtDNA haplotypes are distributed thousands of kilometres apart and across major African watersheds, whereas some neighbouring species carry drastically divergent mtDNA haplotypes. At shallow and deep phylogenetic layers, strong signals of hybridization are attributed to the complex Late Miocene/Early Pliocene palaeohistory of African rivers. Hybridization of multiple lineages across changing watersheds shaped each of the major haplochromine radiations in lakes Tanganyika, Victoria, Malawi and the Kalahari Palaeolakes, as well as a miniature species flock in the Congo basin (River Fwa). On the basis of our results, introgression occurred not only on a spatially restricted scale, but massively over almost the whole range of the haplochromine distribution. This provides an alternative view on the origin and exceptional high diversity of this enigmatic vertebrate group.
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Amasi, Aloyce I. M., Maarten Wynants, Remegius A. Kawalla, Shovi Sawe, Linus Munishi, William H. Blake, and Kelvin M. Mtei. "Reconstructing the Changes in Sedimentation and Source Provenance in East African Hydropower Reservoirs: A Case Study of Nyumba ya Mungu in Tanzania." Earth 2, no. 3 (August 8, 2021): 485–514. http://dx.doi.org/10.3390/earth2030029.
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This study aimed to reconstruct the sedimentation rates over time and identify the changing sources of sediment in a major hydropower reservoir in Tanzania, the Nyumba ya Mungu (NYM). Fallout 210Pb measurements were used to estimate age of sediment deposits and broad changes in sedimentation rates were reconstructed. Sedimentation peaks were cross referenced to geochemical profiles of allogenic and autogenic elemental constituents of the sediment column to confirm a causal link. Finally, geochemical fingerprinting of the sediment cores and potential sources were compared using a Bayesian mixing model (MixSIAR) to attribute the dominant riverine and land use sources to the reservoir together with changes through recent decades. Reservoir sedimentation generally increased from 0.1 g cm−2 yr−1 in the lower sediment column to 1.7 g cm−2 yr−1 in the most recent deposits. These results correlated to changes in allogenic and autogenic tracers. The model output pointed to one of two major tributaries, the Kikuletwa River with 60.3%, as the dominant source of sediment to the entire reservoir, while the other tributary, Ruvu River, contributed approximately 39.7%. However, downcore unmixing results indicated that the latest increases in sedimentation seem to be mainly driven by an increased contribution from the Ruvu River. Cultivated land (CU) was shown to be the main land use source of riverine sediment, accounting for 38.4% and 44.6% in Kikuletwa and Ruvu rivers respectively. This study explicitly demonstrated that the integration of sediment tracing and dating tools can be used for quantifying the dominant source of sediment infilling in East African hydropower reservoirs. The results underscore the necessity for catchment-wide management plans that target the reduction of both hillslope erosion reduction and the sediment connectivity from hillslope source areas to rivers and reservoirs, which will help to maintain and enhance food, water and energy security in Eastern Africa.
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Salman, Salman M. A. "Shared watercourses in the Southern African development community: challenges and opportunities." Water Policy 6, no. 1 (February 1, 2004): 25–38. http://dx.doi.org/10.2166/wp.2004.0002.
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The countries of the Southern African Development Community (SADC) are characterized by sharp variations in size, population, economic development, as well as water availability. The SADC region is, by and large, arid or semi-arid, and as a result faces tremendous challenges in its water sector. The challenges stem from a number of factors, including the high rate of population growth, urbanization and environmental degradation. Those problems are compounded by periodic floods and droughts. Moreover, the region depends, to a considerable extent, on river waters, most of which are shared by two or more states. As such, those shared rivers could be a source of conflict as well as a catalyst for cooperation. This article examines the water resources problems of SADC, with particular emphasis on its shared watercourses, and analyzes the problems therein and the attempts to deal with them.
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Hanzen, Céline, Martyn C. Lucas, Gordon O'Brien, Colleen T. Downs, and Sandi Willows-Munro. "African freshwater eel species (Anguilla spp.) identification through DNA barcoding." Marine and Freshwater Research 71, no. 11 (2020): 1543. http://dx.doi.org/10.1071/mf19390.
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Freshwater eels (Anguilla spp.) have a long and complex catadromous life cycle. This unique feature, coupled with difficulty in separating species based on morphology, makes them complex targets for conservation. In this study we evaluated the utility of DNA barcoding using cytochrome oxidase I (COI) to delimit the four species of African eels found in the western Indian Ocean region. We collected 76 individual fin clips from the four eel species (A. mossambica, n=51; A. marmorata, n=17; A. bengalensis, n=6; A. bicolor, n=2) in the rivers of KwaZulu–Natal, South Africa, in 2016–18. Phylogenetic analysis of the COI sequences recovered all four species as monophyletic. Barcoding gap analyses were performed and there was no found overlap in inter- and intraspecific genetic distances. Consequently, the use of COI barcoding as an identification tool was found to be reliable for identifying African eels to the species level, which suggests that this marker should be included in future environmental DNA or metabarcoding studies.
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Ginal, Philipp, Francisco D. Moreira, Raquel Marques, Rui Rebelo, and Dennis Rödder. "Predicting terrestrial dispersal corridors of the invasive African clawed frog Xenopus laevis in Portugal." NeoBiota 64 (January 28, 2021): 103–18. http://dx.doi.org/10.3897/neobiota.64.60004.
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Invasive species, such as the mainly aquatic African clawed frog Xenopus laevis, are a main threat to global biodiversity. The identification of dispersal corridors is necessary to restrict further expansion of these species and help to elaborate management plans for their control and eradication. Here we use remote sensing derived resistance surfaces, based on the normalised difference vegetation index (NDVI) and the normalised difference water index (NDWI) accounting for behavioural and physiological dispersal limitations of the species, in combination with elevation layers, to determine fine scale dispersal patterns of invasive populations of X. laevis in Portugal, where the frog had established populations in two rivers. We reconstruct past dispersal routes between these two invaded rivers and highlight high risk areas for future expansion. Our models suggest terrestrial dispersal corridors that connect both invaded rivers and identify artificial water bodies as stepping stones for overland movement of X. laevis. Additionally, we found several potential stepping stones into novel areas and provide concrete information for invasive species management.
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Hepper, F. Nigel. "The Niger and the Nile: Botanical Exploration Around Two African Rivers." Annals of the Missouri Botanical Garden 78, no. 1 (1991): 81. http://dx.doi.org/10.2307/2399592.
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Habel, J. C., Mike Teucher, Werner Ulrich, and Thomas Schmitt. "Documenting the chronology of ecosystem health erosion along East African rivers." Remote Sensing in Ecology and Conservation 4, no. 1 (July 19, 2017): 34–43. http://dx.doi.org/10.1002/rse2.55.
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Hugueny, Bernard. "West African rivers as biogeographic islands: species richness of fish communities." Oecologia 79, no. 2 (1989): 236–43. http://dx.doi.org/10.1007/bf00388483.
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Triest, Ludwig, Henri Lung’ayia, George Ndiritu, and Abebe Beyene. "Epilithic diatoms as indicators in tropical African rivers (Lake Victoria catchment)." Hydrobiologia 695, no. 1 (June 22, 2012): 343–60. http://dx.doi.org/10.1007/s10750-012-1201-2.
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Allen, Kaitlin E., Eli Greenbaum, Paul M. Hime, Walter P. Tapondjou N., Viktoria V. Sterkhova, Chifundera Kusamba, Mark‐Oliver Rödel, Johannes Penner, A. Townsend Peterson, and Rafe M. Brown. "Rivers, not refugia, drove diversification in arboreal, sub‐Saharan African snakes." Ecology and Evolution 11, no. 11 (May 2021): 6133–52. http://dx.doi.org/10.1002/ece3.7429.
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Gordon, AK, NJ Griffin, and CG Palmer. "The relationship between concurrently measured SASS (South African Scoring System) and turbidity data archived in the South African River Health Programme’s Rivers Database." Water SA 41, no. 1 (December 1, 2014): 21. http://dx.doi.org/10.4314/wsa.v41i1.4.
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Blackmore, Andrew. "Legal and Public Trust Considerations for the Ndumo Game Reserve and South Africa-Mozambique Border, following the Migration of the Usuthu River." Southern African Public Law 30, no. 2 (December 1, 2017): 347–78. http://dx.doi.org/10.25159/2522-6800/3585.
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The Usuthu River forms part of the international boundary between South Africa and Mozambique. In 2002, this River breached its south bank within the Ndumo Game Reserve and established a new channel within the protected area. In response to the breach, Mozambique proposed the excavation of the floodplain and the establishment of berms to force the flow of the river back into its original alignment. Analysis of the origin and associated history of this portion of the international boundary indicates that it is unlikely that the international boundary has moved with the breech. Furthermore, customary international law pertaining to avulsion or mutation alvei of rivers supports the notion that the international boundary remained in the original channel of the Usuthu River. Finally, case history of a similar circumstance in Africa affirms that this boundary is unlikely to have shifted with the avulsion of the Usuthu River. The Mozambican proposal brings to the fore an array of public trust considerations which are founded in South Africa’sConstitution, and environmental and biodiversity conservation legislation. These considerations prohibit the excavation of the Ndumo Game Reserve. The concept of the state acting as a trustee for, inter alia, biodiversity and protected areas, is reinforced by various water and biodiversity-orientated multilateral agreements to which South Africa is a signatory. Within these, the ones adopted by the Southern African Development Community are the most profound in that they, and specifically the Protocol on Wildlife Conservation and Law Enforcement, enjoin state parties from taking decisions that may cause damage to the trust entity beyond the limits of their sovereignty.
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Osho, F. E., B. O. Omitoyin, and E. K. Ajani. "Haematology, serum biochemistry and condition factor of the African snakehead fish, Parachanna obscura from Nigeria’s hydrologic areas." Ife Journal of Science 22, no. 3 (January 25, 2021): 75–83. http://dx.doi.org/10.4314/ijs.v22i3.6.
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Rapid change in the conservation status of Parachanna obscura from least concerned to endangered species raises concerns over the health of the natural populations of this stock in Nigeria. This study therefore investigated the haematology, serum biochemistry and condition factor of P. obscura from Nigeria's freshwater environment to assess their wellbeing. All eight hydologic areas in Nigeria were purposively selected while one river in each of the basins was randomly chosen for sampling of P. obscura. These randomly selected rivers were from Anambra (Niger South), Imo (Eastern south) , Ibbi (Upper Benue), Kaduna (Niger Central), Katsina Ala (Lower Benue), Hadejia (Lake Chad), Ogun (Western Littoral) , and Sokoto (Niger North) rivers. Fish samples were collected quaterly for a year from fishermen's catch. One-way ANOVA and Duncan's Multiple Range Test were employed for data analysis. Percentage parked cell volume, lymphocytes, neutrophil and monocytes as well as haemoglobin and red blood cells were not significantly different (p>0.05) across populations. However, other haematologic parameters differed significantly among the populations. Samples from river Ibbi had significantly higher levels of glucose (47.75±3.22 mg/dL), aspartate aminotransferase (42.25±2.72 U/L), alanine aminotransferase (33.25±2.14 U/L) and blood urea nitrogen (1.91±0.31 mg/dL). Condition factors averaged 0.81±0.01. The present study showed that measured haematologic and serum biochemistry parameters as well as the condition factor were within normal reference values for P. obscura or similar tropical fish species reference values. Therefore, other causes of the decline in population of this species in Nigeria should be investigated.
Keywords: Parachanna obscura, Nigeria's freshwater environment, Population decline, Endangered tropical fish species.
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Amiriheobu, Frank, Ekperi Watts, Anthony Terry, and George Owunari. "AFRICAN DEITY AND PEACE DEVELOPMENT IN JULIE OKOH’S WE ARE RIVERS AND THE NIGERIAN SPACE." International Journal of Strategic Research in Education, Technology and Humanities 8, no. 1 (September 3, 2020): 83–95. http://dx.doi.org/10.48028/iiprds/ijsreth.v8.i1.08.
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Until recent time, African deities, positioned as viable medium of creating sanity and tranquility in the African front have been ironically neglected due to incursion of Christianization, civilization, modernization, and advanced technology. The efficacy of the African deity which is paramount insomuch that it preserves the culture, tradition, norms, values, artifacts, morals, and way of lives of the people, thus militating against evil forces whose agenda is targeted at the people, by increasing the level of death, sickness, ailment, farming, barrenness, strive, poverty, and every other forms of wickedness as portrayed in Julie Okoh’s We Are Rivers, is today, neglected and most often abolished. This has unequivocally created fear and pain of the people and underdevelopment to the nation. It has therewith created impetus for creative portraiture in dramatic and argumentative representations by dramatist and critics over the years, yet, the issue is still persisting. The study therefore aims at repositioning African Deity as viable medium of sanity and a mechanism of enhancing peace and development in the Nigerian space. Thus, with content analytical methodology, this study investigates how Julie Okoh attempts to establish the cause and effect of deity negligence and service on the Nigerian space using the instrument of drama. The effect of it will create positive change amongst Nigerians, thus, create change in their society. The study therefore recommends that maximum attention be made towards promoting African deity to the frontier of politicians as that would define the hallmark of peace and development.
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Tooth, S., D. Brandt, P. J. Hancox, and T. S. McCarthy. "Geological controls on alluvial river behaviour: a comparative study of three rivers on the South African Highveld." Journal of African Earth Sciences 38, no. 1 (January 2004): 79–97. http://dx.doi.org/10.1016/j.jafrearsci.2003.08.003.
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Sperna Weiland, F. C., L. P. H. van Beek, J. C. J. Kwadijk, and M. F. P. Bierkens. "Global patterns of change in discharge regimes for 2100." Hydrology and Earth System Sciences 16, no. 4 (April 2, 2012): 1047–62. http://dx.doi.org/10.5194/hess-16-1047-2012.
Full textAbstract:
Abstract. This study makes a thorough global assessment of the effects of climate change on hydrological regimes and their accompanying uncertainties. Meteorological data from twelve GCMs (SRES scenarios A1B and control experiment 20C3M) are used to drive the global hydrological model PCR-GLOBWB. This reveals in which regions of the world changes in hydrology can be detected that have a high likelihood and are consistent amongst the ensemble of GCMs. New compared to existing studies is: (1) the comparison of spatial patterns of regime changes and (2) the quantification of notable consistent changes calculated relative to the GCM specific natural variability. The resulting consistency maps indicate in which regions the likelihood of hydrological change is large. Projections of different GCMs diverge widely. This underscores the need of using a multi-model ensemble. Despite discrepancies amongst models, consistent results are revealed: by 2100 the GCMs project consistent decreases in discharge for southern Europe, southern Australia, parts of Africa and southwestern South-America. Discharge decreases strongly for most African rivers, the Murray and the Danube while discharge of monsoon influenced rivers slightly increases. In the Arctic regions river discharge increases and a phase-shift towards earlier peaks is observed. Results are comparable to previous global studies, with a few exceptions. Globally we calculated an ensemble mean discharge increase of more than ten percent. This increase contradicts previously estimated decreases, which is amongst others caused by the use of smaller GCM ensembles and different reference periods.
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Sperna Weiland, F. C., L. P. H. van Beek, J. C. J. Kwadijk, and M. F. P. Bierkens. "Global patterns of change in discharge regimes for 2100." Hydrology and Earth System Sciences Discussions 8, no. 6 (December 13, 2011): 10973–1014. http://dx.doi.org/10.5194/hessd-8-10973-2011.
Full textAbstract:
Abstract. This study makes a thorough global assessment of the effects of climate change on hydrological regimes and their accompanying uncertainties. Meteorological data from twelve GCMs (SRES scenarios A1B, and control experiment 20C3M) are used to drive the global hydrological model PCR-GLOBWB. We reveal in which regions of the world changes in hydrology can be detected that are significant and consistent amongst the ensemble of GCMs. New compared to existing studies is: (1) the comparison of spatial patterns of regime changes and (2) the quantification of consistent significant change calculatesd relative to both the natural variability and the inter-model spread. The resulting consistency maps indicate in which regions likelihood of hydrological change is large. Projections of different GCMs diverge widely. This underscores the need of using a multi-model ensemble. Despite discrepancies amongst models, consistent results are revealed: by 2100 the GCMs project consistent decreases in discharge for southern Europe, southern Australia, parts of Africa and southwestern South-America. Discharge decreases are large for most African rivers, the Murray and the Danube. While discharge of Monsoon influenced rivers slightly increases. In the Arctic regions river discharge increases and a phase-shift towards earlier peaks is observed. Results are comparable to previous global studies, with a few exceptions. Globally we calculated an ensemble mean discharge increase of more than ten percent. This increase contradicts previously estimated decreases, which is amongst others caused by the use of smaller GCM ensembles and different reference periods.