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RELATIVELY NEGATIVE δ13C RATIOS OF MESOZOOPLANKTON IN THE SUNDAYS RIVER ESTUARY, COMMENTS ON POTENTIAL CARBON SOURCES
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: H.L. Jerling --- Department of Zoology, South Africa T.H. Wooldridge --- Department of Zoology, South AfricaMesozooplankton, submergent and fringing macrophytes and particles suspended in the water column in the Sundays River estuary South Africa were analyzed for δ13C isotope ratios. Highly negative values (−28.3‰ to −32.0‰) for the mesozooplankton species suggest the possibility of phytoplankton... -
Examining the 'global spreading hypothesis' using graph theory
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: F Jordán T WyattA persistent view, called the 'global spreading hypothesis', maintains that the frequency, magnitude and geographical extent of harmful algal blooms have increased in recent decades. These putative trends have been variously attributed to nutrient enrichment, climate change and inadequate databases... -
HAB outreach using multimedia: integrating ocean research and education
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A deCharon S Etheridge T McDonnell Wysor M SierackiThis paper highlights a few of the education and outreach products on harmful algal blooms (HABs) that have been developed at Bigelow Laboratory for Ocean Sciences, a non-profit organisation dedicated to marine biological research and education. The 'Toxic & Harmful... -
Cross-shelf observations of diet and diel feeding behaviour of the bearded goby Sufflogobius bibarbatus off Namibia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Hundt --- Department of Biology, Norway AC Utne-Palm --- Department of Biology, Norway MJ Gibbons --- Department of Biodiversity and Conservation Biology, South AfricaThe diet of the bearded goby Sufflogobius bibarbatus was studied at two 48 h stations off the Namibian coast. The inner station (120 m) was characterised by a deep layer of low-oxygen bottom water (<0.5 ml DO l−1 or <10%... -
Changes in the trophic structure of the southern Benguela before and after the onset of industrial fishing
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KE Watermeyer LJ Shannon CL GriffithsDespite a human presence in the Benguela region for at least one million years, exploitation of marine resources by European seafarers only began in earnest in the 1400s. Ecopath with Ecosim was used to construct and compare mass-balanced foodweb models... -
Changes in the trophic structure of the northern Benguela before and after the onset of industrial fishing
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KE Watermeyer LJ Shannon J-P Roux CL GriffithsExploitation of marine resources has been occurring in the northern Benguela ecosystem for centuries. Understanding the cumulative long-term effects of this exploitation is important toward effective management of the modern system. Retrospective mass-balanced models of the ecosystem have been constructed,... -
Effects of fishing on a temperate reef community in South Africa 2: benthic invertebrates and algae
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Götz --- , South Africa SE Kerwath --- Department of Environmental Affairs, South Africa CG Attwood --- Marine Research Institute, Department of Zoology, South Africa WHH Sauer --- Department of Ichthyology and Fisheries Science, South AfricaThe effect of fishing on benthic reef communities was studied by comparing reefs within and outside the Goukamma Marine Protected Area (MPA) on the South African warm-temperate south coast. Although study sites were similar in terms of bathymetry and oceanographic... -
Modelling the impacts of semi-intensive aquaculture on the foodweb functioning of a Nile Delta coastal lake
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Bocci --- Department of Environmental Sciences, Informatics and Statistics, Italy R Pastres --- Department of Environmental Sciences, Informatics and Statistics, Italy S Kholeif --- National Institute of Oceanography and Fisheries (NIOF), Egypt D Dalla Barba --- Department of Environmental Sciences, Informatics and Statistics, Italy D Brigolin --- Department of Environmental Sciences, Informatics and Statistics, ItalyNutrient loadings are an important component of aquaculture impacts as they can lead to cascade effects at the ecosystem level. An evaluation of these effects on foodweb functioning is presented and discussed for the case study of Lake Burullus in... -
Water hyacinth (Eichhornia crassipes) affects the composition and abundance of zooplankton in the littoral region of Koka Reservoir, Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: H Getnet --- , Ethiopia D Kifle --- , Ethiopia T Fetahi --- , EthiopiaWater hyacinth, Eichhornia crassipes (Martius) Solms 1883, is a rampant invasive aquatic plant that is recognised as one of the ten worst weeds in the world. Its appearance in Koka Reservoir was reported in 1965 and since then it has... -
Comparative analysis of habitat structure and macroinvertebrate assemblages in headwater streams of Odzi sub-catchment, Chimanimani District, Zimbabwe, post Cyclone Idai-induced flooding
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Brian Mamvura --- , Zimbabwe Tongayi Mwedzi --- Chinhoyi University of Technology, Zimbabwe Beaven Utete --- Chinhoyi University of Technology, ZimbabweFlooding results in short and long-term modifications of aquatic ecosystem structure and biodiversity. Cyclone Idai, which ravaged through Zimbabwe in 2019, had devastating consequences on aquatic ecosystems. However, the extent of habitat modification and consequent biodiversity shifts are unknown. This...