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The accumulation of nitrate in Kikuyu grass (Pennisetum clandestinum Hochst)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.P. Marais --- Biochemistry Section, Republic of South Africa D.L. Figenschou --- Biochemistry Section, Republic of South Africa C. Dennison --- Department of Biochemistry, Republic of South AfricaA study was made of some of the factors responsible for the accumulation of excessive amounts of nitrate in certain Kikuyu pastures. Accumulation, mainly in stem tissue, is the nett result of several contributing processes. Climatic conditions causing a decline... -
Seasonal uptake of phosphorus, potassium, calcium and magnesium by young peach trees
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P. J.C. Stassen --- Department of Agronomy and Horticulture, Republic of South Africa J.D. Stadler --- , Republic of South AfricaTwo-year-old peach trees, grown in sand culture were destructively sampled over a period of 14 months, to determine the uptake of phosphorus, potassium, calcium and magnesium in the new growth (leaves, fruit and new shoots) and in the permanent structure... -
Evaluation of proline accumulation as an indicator of drought tolerance in spring wheat cultivars
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P. D.R. van Heerden --- Department of Botany, Republic of South Africa O.T. de Villiers --- Department of Botany, Republic of South AfricaThe aim of this study was to evaluate proline accumulation as an indicator of drought stress and drought tolerance in spring wheat cultivars (Triticum aestivum L.) grown in the Western Cape. Drought stress was induced in whole plants and leaf... -
Brushpiles and dung as rehabilitation patches: effect on soil resources in degraded succulent thicket, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: WB Todkill GIH Kerley EE CampbellA substantial portion of the Thicket Biome in the Eastern Cape has been transformed by overgrazing. An experimental rehabilitation study of degraded succulent thicket was initiated to determine whether increasing the patchiness on the landscape would result in an increase... -
Boundedly UC spaces: characterisations and preservation
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Tanvi Jain S. KunduA metric space (X, d) is called a boundedly UC space if every closed and bounded subset of X is a UC space. A metric space (X, d) is called a UC space if each real-valued continuous function on (X,... -
Gill damage, metallothionein gene expression and metal accumulation in Tilapia sparrmanii from selected field sites at Rustenburg and Potchefstroom, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Daléne van Heerden Peet Jansen van Rensburg Mikko Nikinmaa André VoslooFish were collected from field sites in the mining and agricultural areas of Potchefstroom and Rustenburg, North-West Province, South Africa. Water and sediment samples from each site, together with fish muscle and gills, were analysed by Inductively Coupled Plasma Mass... -
Ecophysiological responses of the salt marsh grass Spartina maritima to salinity
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: G Naidoo --- School of Biological and Conservation Sciences, South Africa Y Naidoo --- School of Biological and Conservation Sciences, South Africa P Achar --- Department of Biological and Physical Sciences, USAThe effects of salinity on growth and productivity of Spartina maritima (Curtis) Fernald were investigated in glasshouse and field experiments in 2008. In the glasshouse study, plants were subjected to 2%, 10%, 20%, 40% and 80% sea water, with tidal... -
Distribution and enrichment of metals in sediments of the Ogun River within Abeokuta, south-western Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: KA Olatunde --- Department of Environmental Management and Toxicology, Nigeria TA Arowolo --- Department of Environmental Management and Toxicology, Nigeria BS Bada --- Department of Environmental Management and Toxicology, Nigeria AM Taiwo --- Department of Environmental Management and Toxicology, Nigeria ZO Ojekunle --- Department of Environmental Management and Toxicology, NigeriaThe distribution and enrichment of metals in the sediments of Ogun River within Abeokuta City, south-western Nigeria, were assessed in 2007. Replicate samples of sediments were collected from 10 sampling sites along the length of the river within the city... -
Uptake and accumulation of ammonium by Alexandrium catenella during nutrient pulses
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: Y Collos M Lespilette A Vaquer M Laabir A PastoureaudField observations in Thau Lagoon, southern France, indicate that the growth of natural populations of Alexandrium catenella during blooms is limited by nitrogen and exhibits a storage rather than a growth response to an ammonium pulse. Therefore, ammonium uptake and... -
Feeding of the tintinnid ciliate Favella taraikaensis on the toxic dinoflagellate Alexandrium tamarense and the fate of prey toxins
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Kamiyama T Suzuki Y OkumuraTo establish the fate of paralytic shellfish poisoning (PSP) toxins in planktonic foodwebs, feeding activities of the planktonic ciliate Favella taraikaensis on the PSP-producing alga Alexandrium tamarense were examined in laboratory experiments and the toxin content in the ciliates was... -
Bioaccumulation of cadmium in the ascidian Styela clava (Herdman 1881)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Jiang --- Department of Biochemical Engineering, China Z Yu --- Department of Biochemical Engineering, China CH Wang --- Department of Biochemical Engineering, ChinaThe processes of bioaccumulation and elimination of cadmium by tissues of Styela clava (Herdman 1881) were investigated based on a semi-static two-compartment model. The kinetic parameters (accumulation rate constant k 1, elimination rate constant k 2, bioconcentration factor BCF, biological... -
Bioaccumulation of metals in Tilapia zillii from Badeni Dam, Côte d'Ivoire
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RB Tate --- Digby Wells Environmental, South Africa A Husted --- Digby Wells Environmental, South AfricaGiven the importance of fish as a source of protein and the potential for exposure of humans to metal elements, metal bioaccumulation concentrations in Tilapia zillii from four sites in the Badeni Dam on the Badeni River, Côte d'Ivoire, were... -
Innovative fluorescence detection technique for metals in cestode egg-shells
Item type: Journal Article • Journal: African Zoology • Authors: N. Degger --- Department of Zoology, South Africa A. Avenant-Oldewage --- Department of Zoology, South Africa R. Greenfield --- Department of Zoology, South AfricaRecent work in the field of parasitology has drawn attention to the application of parasites as pollution-accumulation indicators, particularly cestodes. A discrepancy in metal concentrations within cestode posterior and anterior tissue has led researchers to attribute this phenomenon to metals... -
Lead accumulation in and its haematological effects on African catfish Clarias gariepinus
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DH Ogbuagu --- Department of Environmental Technology, Nigeria ET Adebayo --- Department of Fisheries and Aquaculture Technology, Nigeria AA Ayoade --- Hydrobiology and Fisheries Unit, Department of Zoology, Nigeria OB Ugwu --- Department of Fisheries and Aquaculture Technology, Nigeria DO Mba --- Department of Fisheries and Aquaculture Technology, NigeriaYoung adult Clarias gariepinus exposed to 0.0015–0.1500 µg l−1 concentrations of lead (Pb2+) ions for 30 days were investigated for accumulations in muscle, gill, liver and heart tissues, as well as for the metal's effects on haemoglobin concentrations, erythrocytes sedimentation... -
Polycyclic aromatic hydrocarbons in water, sediment and fish from the Warri River at Ubeji, Niger Delta, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MC Asagbra --- Ecology and Environmental Biology Research Unit, Department of Zoology, Nigeria AS Adebayo --- Cell Biology and Genetics Unit, Department of Zoology, Nigeria CI Anumudu --- Cell Biology and Genetics Unit, Department of Zoology, Nigeria OA Ugwumba --- Hydrobiology and Fisheries Research Unit, Department of Zoology, Nigeria AAA Ugwumba --- Hydrobiology and Fisheries Research Unit, Department of Zoology, NigeriaThe Warri River at Ubeji, Nigeria, receives pollutants from an oil refinery. The levels of 16 priority polycyclic aromatic hydrocarbons (PAHs) in water, sediment and the tissue of tilapia from the Warri River were investigated in 2010 using gas chromatography... -
An evaluation of the weight of evidence approach to assess sediment quality in the Mvoti Estuary, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BF Shaddock --- Department of Zoology, South Africa V Wepener --- Water Research Group, Unit for Environmental Sciences and Management, South AfricaA weight of evidence approach was evaluated in the Mvoti Estuary, which is affected by point and non-point sources of contaminants. Four sites were sampled in 2005 and assessed along the standard sediment quality triad lines of evidence: sediment chemistry,... -
Uptake and distribution of copper in the freshwater crab Potamonautes perlatus (Crustacea) in the Eerste River, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: R.G. Snyman --- Department of Zoology, South Africa A.J. Reinecke [AN0001] J.A.J. Nel --- Department of Zoology, South AfricaThe uptake and distribution of copper in the freshwater crab Potamonautes perlatus in the Eerste River, South Africa, were studied seasonally by comparing copper concentrations in crabs, water and sediment at two localities, one upstream and one downstream from the... -
Metal contamination and human health risk associated with the consumption of Labeo rosae from the Olifants River system, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: J Lebepe --- Department of Biodiversity, South Africa SM Marr --- Department of Biodiversity, South Africa WJ Luus-Powell --- Department of Biodiversity, South AfricaThe Olifants River, a tributary of the Limpopo River system, is one of the most polluted rivers in South Africa. In May 2011 the concentrations of metals in fish muscle tissue from two impoundments, Loskop and Flag Boshielo dams, on... -
Metal accumulation in House Sparrow (Passer domesticus) from Thohoyandou, Limpopo province, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Nathan J Baker --- Department of Zoology, South Africa Simone Dahms --- Department of Zoology, South Africa Ruan Gerber --- Department of Zoology, South Africa John Maina --- Department of Zoology, South Africa Richard Greenfield --- Department of Zoology, South AfricaStudies on metal pollution (cadmium, cobalt, chromium, copper, manganese and nickel) in South African terrestrial environments are severely lacking. Due to being relatively unaffected by industrialisation, the Thohoyandou region may provide data on natural levels of metals for use as... -
Determination of water quality, and trace metals in endemic Sarotherodon linellii, Pungu maclareni and Clarias maclareni, in crater Lake Barombi Mbo, Cameroon
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BN Sone --- Faculty of Environmental Sciences and Natural Resource Management, Norway. Current address: c/o P Ndumbe, Standard Chartered Bank, Yaounde, Cameroon BO Rosseland --- Faculty of Environmental Sciences and Natural Resource Management, Norway. Current address: c/o P Ndumbe, Standard Chartered Bank, Yaounde, Cameroon H-C Teien --- Faculty of Environmental Sciences and Natural Resource Management, Norway. Current address: c/o P Ndumbe, Standard Chartered Bank, Yaounde, CameroonConsidering water pollution as a potential threat to some endemic cichlids of Lake Barombi Mbo, Cameroon, an investigation was done in 2011 to determine trace metals in its water, linking their uptake in gills and liver of fish to water... -
Heavy metal contamination of water and fish in peri-urban dams around Bulawayo, Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: C Teta --- Department of Environmental Science and Health, Zimbabwe M Ncube --- Department of Environmental Science and Health, Zimbabwe YS Naik --- Department of Environmental Science and Health, ZimbabweUrban effluents are significant sources of heavy metal pollution in fresh water. Metal contamination in dams around the city of Bulawayo, Zimbabwe, were monitored during October 2014 to assess ecological and public health risks. Heavy metals were measured in water,... -
Metal accumulation in two contiguous eutrophic peri-urban lakes, Chivero and Manyame, Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Utete --- Chinhoyi University of Technology, Zimbabwe C Phiri --- Chinhoyi University of Technology, Zimbabwe SS Mlambo --- Chinhoyi University of Technology, Zimbabwe N Maringapasi --- Chinhoyi University of Technology, Zimbabwe N Muboko --- Chinhoyi University of Technology, Zimbabwe TB Fregene --- Department of Aquaculture and Fisheries Management, Nigeria B Kavhu --- University of Zimbabwe, ZimbabweConcentrations of aluminium, cadmium, chromium, cobalt, copper, iron, lead, nickel and zinc were determined in surface water, benthic sediments, and the gills, liver and stomach muscle tissues of Oreochromis niloticus and Clarias gariepinus in peri-urban lakes Chivero and Manyame, Zimbabwe... -
Health and chemical burdens of fish species from polluted and hyper-eutrophic freshwater ecosystems in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GM Wagenaar --- Department of Zoology, South Africa IEJ Barnhoorn --- Department of Zoology, South AfricaThree aquatic ecosystems in South Africa, the Hartbeespoort, Klipvoor and Bospoort Dams, are classified as hyper-eutrophic, because of high nutrient loads and chemical pollution. Water and two fish species, Clarias gariepinus and Cyprinus carpio, were collected from these dams to... -
Gender appropriateness of field days in knowledge generation and adoption of push-pull technology in eastern Africa
Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: AW Murage --- Kenya Agricultural and Livestock Research Organization (KALRO), JO Pittchar --- International Centre of Insect Physiology and Ecology (ICIPE), Kenya CAO Midega --- International Centre of Insect Physiology and Ecology (ICIPE), Kenya CO Onyango --- Asian Vegetable Research and Development Centre (ADRDC), JA Pickett --- Rothamsted Research, United Kingdom ZR Khan --- International Centre of Insect Physiology and Ecology (ICIPE), KenyaAdoption studies have identified gender as one of the factors that determine technology uptake and this has been linked to women’s access to farming information or lack of it. Technology scaling up systems should utilise pathways that are compatible with... -
Assessment of trace metals in water samples and tissues of African catfish (Clarias gariepinus) from the Akaki River Catchment and the Aba Samuel Reservoir, central Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AB Kassegne --- Centre for Environmental Science, Ethiopia T Berhanu --- Interim Coordinator, Central Research Laboratory, Ethiopia JO Okonkwo --- Department of Environmental, Water and Earth Sciences, South Africa S Leta --- Centre for Environmental Science, EthiopiaConcentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined in water and muscle of Clarias gariepinus from the Akaki River Catchment and the Aba Samuel Reservoir in Ethiopia during 2016 and 2017. The analyses were performed... -
Occurrence of selected pharmaceuticals in industrial wastewater, receiving waters and fish
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SM Lan --- Ecotoxicology Unit, Department of Zoology, Nigeria NH Amaeze --- Ecotoxicology Unit, Department of Zoology, Nigeria HE Obanya --- Ecotoxicology Unit, Department of Zoology, Nigeria CU Okoroafor --- Ecotoxicology Unit, Department of Zoology, NigeriaData on pharmaceutical contamination of African waterbodies are scarce. Therefore, this research aimed to quantify the occurrence of selected pharmaceuticals in wastewater from pharmaceutical industries, receiving waters and fish. Water and fish samples were collected from waterbodies close to two... -
Response of the barrier island coastal region of southwestern Nigeria to climate and non-climate forcing
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: IB Danladi --- Department of Geological Engineering, Turkey M Gül --- Department of Geological Engineering, Turkey E Ateş --- Vocational School of Ayaş, TurkeyDespite threats emanating from the influence of climate and non-climate forcing on the barrier island coastal region of southwestern Nigeria, the extent of the coastal erosion is poorly understood. We report evidence of coastal erosion and sediment accumulation in the... -
Growth and metabolism of Clarias gariepinus (Burchell, 1822) fed with copepods (Eucyclops sp.) exposed to lead and titanium dioxide nanoparticles
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MM Matouke --- , Nigeria MK Mustapha --- , NigeriaThe increasing uses of lead (Pb2+) and titanium dioxide nanoparticles (nTiO2) in commercial products have led totheir increased discharge into aquatic environments. This study investigated the effects of the interaction betweennTiO2 and lead (Pb2+) in a simple freshwater food web... -
Monitoring metals in South African harbours between 2008 and 2009, using resident mussels as indicator organisms
Item type: Journal Article • Journal: African Zoology • Authors: V Wepener --- , South Africa N Degger --- , FranceMore than 65% of the South African coastline is threatened as a result of pollution, a large proportion of which is land derived. To date the majority of published data on metal monitoring has been on limited regions or once-off... -
Physiological response of ryegrass (Lolium spp.) grown at different temperatures to glufosinate ammonium application
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Tendai Mucheri --- , South Africa Petrus J Pieterse --- , South Africa Carl F Reinhardt --- , South Africa Aleysia Kleinert --- , South AfricaEfficacy of glufosinate ammonium is influenced by temperature. However, several studies show variable results. The response of ryegrass (Lolium spp.) to glufosinate ammonium activity at different temperatures was investigated. Ryegrass was grown at 10/15, 15/20, 20/25, and 25/30 °C (night/day)... -
Heavy metal profiles in limpets and algae on the Eastern Cape coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Mbandzi --- , South Africa MDV Nakin --- , South Africa GM Saibu --- , South Africa AO Oyedeji --- , South AfricaHeavy metal pollution is an increasing threat to the marine environment and is a major health concern. Both marine limpets and algae have been employed as biomonitors elsewhere in the world, but there are few or no data for these... -
Emotional intelligence and academic success among South African engineering students
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Barend J. van Wyk --- , South Africa Henry D. Mason --- , South AfricaThis study explored the relationship between emotional intelligence and academic success among a sample of 1 346 South African engineering students. Data were collected from the students using the Emotional Skills Assessment Process (ESAP). Academic success was calculated using the... -
Comparison of calcium concentration in scales and vertebral column of a cyprinid from calcium-limited environments in the Lake Victoria Basin, Uganda
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: WA Nesbitt --- , Canada SB Clarke --- , Canada LJ Chapman --- , CanadaDespite dramatic differences in calcium concentrations within aquatic systems, very few studies have explored the relationships between ambient calcium concentration and the calcium concentration of resident fish under natural conditions. This study compares calcium concentration in the water to that... -
Women’s self-help groups and asset accumulation in peri-urban Wa, Ghana
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ibrahim Abu Abdulai --- , Ghana Shaibu Bukari --- , Ghana Moses Naiim Fuseini --- , GhanaWomen’s self-help groups (SHGs) play an essential role in the fight against poverty. Despite this, studies on the impact of SHGs on women’s asset accumulation and incomes tend to focus on rural and urban areas, with peri-urban areas receiving little... -
Human capital accumulation and economic growth of Ethiopian economy
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Zemed Degu Mengesha --- Punjabi University, India Lakhwinder Singh --- Punjabi University, IndiaEconomic theory, empirical studies and public policy have underlined the importance of the relationship between human capital accumulation and economic growth. Several developing countries have included human capital development as an integral part of their national development plans and have... -
Southern mullets (Chelon richardsonii) as a potential biological indicator for mercury pollution in the Walvis Bay lagoon, Namibia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Veronica Kaleinasho Kapula --- University of Namibia, Namibia Hilkka Opolili Ndahafa Ndjaula --- University of Namibia, Namibia Stephanus Hamutenya --- , Namibia Johannes Angala Iitembu --- University of Namibia, NamibiaSouthern mullet Chelon richardsonii is one of the important fish species found in the Walvis Bay lagoon (WBL) that is commercially exploited for local consumption. The southern mullet is, however, exposed to mercury (Hg) found in sediments, which forms part... -
Heavy metal contamination in mangrove ecosystems: assessing bioaccumulation in crabs and snails along the Bayelsa Coast, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HO Adamu --- University of Bremen, Germany JI Izegaegbe --- University of Eastern Finland, Finland RO Hussaini --- Ambrose Alli University, Nigeria EM Odoya --- Ambrose Alli University, Nigeria HO Adamu --- Federal Ministry of Water Resources, NigeriaRapid human population growth and industrial activities along coastal areas have intensified anthropogenic contamination in water, sediment and edible fauna, posing public health risks. Mangrove ecosystems act as pollutant sinks, increasing the likelihood of heavy metal accumulation in aquatic organisms...