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THE PROCESSING OF UNCONFINED, NATURALLY ENTRAINED LEAVES IN TWO LOW-ORDER SOUTHERN AFRICAN MOUNTAIN STREAMS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: S.J. Lamberth --- Zoology Department, South Africa B.A. Stewart --- , South Africa B.R. Davies --- Zoology Department, South AfricaBreakdown of unconfined and confined leaves of the riparian tree Brabejum stellatifolium L. was investigated in two low order mountain streams (Window Stream and Langrivier) in the southwestern Cape, South Africa. At both sites, 5000 unconfined leaves were released in... -
THE EFFECTS OF TROUT-FARM EFFLUENTS ON BENTHIC INVERTEBRATE COMMUNITY STRUCTURE IN RIVERS IN THE SOUTH-WESTERN CAPE, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: C.A. Brown --- Freshwater Research Unit, Zoology Department, J.M. King --- Freshwater Research Unit, Zoology Department,The south-western Cape is currently responsible for 45% of the total annual trout production in South Africa and further expansion of this industry in the region is likely. A preliminary survey of seven trout farms situated on the upper reaches... -
A comparison of several methods of assessing river condition using benthic macroinvertebrate assemblages
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CA BrownThis paper attempts to address some of the problems that are faced in the endeavour to minimise the time and financial costs of environmental monitoring. At the same time, it aims to assess the usefulness to freshwater studies of some... -
Fish migrations in two seasonal streams in Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Brian Gratwicke BrianE MarshallFish migrations into the streams of seasonally-flooded depressions (or dambos) that cover the central plateaus of Africa are a well-known phenomenon to scientists and lay people alike. However, the factors causing seasonal migrations are poorly understood and most scientific references... -
The toxicity of zinc to a selected macroinvertebrate, Adenophlebia auriculata (Ephemeroptera, Leptophlebiidae): method development
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: V Everitt --- Centre for Aquatic Toxicology, South Africa P-A Scherman --- Centre for Aquatic Toxicology, South Africa MH Villet --- Department of Zoology and Entomology, South AfricaThe South African water quality guidelines for the protection of the aquatic environment are constantly being updated. The Centre for Aquatic Toxicology of the Institute for Water Research, Rhodes University, uses artificial streams and toxicological methods to contribute to the... -
An overview of the structure and function of microbial biofilms, with special emphasis on heterotrophic aquatic microbial communities
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AW Muia --- Department of Biological Sciences, Kenya G Bretschko --- , Austria GJ Herndl --- Department of Biological Oceanography, The NetherlandsAn overview is presented of the formation, structure and development of biofilms, and of the roles and functions of heterotrophic microbial communities in streambeds, in order to stimulate interest and research in this field in Africa. Microbial biolfilms are of... -
A preliminary assessment of the impact of forest conversion from natural to pine plantation on macroinvertebrate communities in two mountain streams in Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Chakona B MarshallThis study presents preliminary data on the influence of forest conversion from natural to pine plantation on benthic macroinvertebrates in streams in the Chimanimani Mountains in the Eastern Highlands of Zimbabwe, a region that has received little attention with respect... -
A preliminary benthic macroinvertebrate index of biotic integrity (B-IBI) for monitoring the Moiben River, Lake Victoria Basin, Kenya
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: FO Masese PO Raburu M MuchiriA Benthic Index of Biotic Integrity (B-IBI) was developed for the Moiben River. The index assesses effects of human disturbance on the biotic condition of stream macroinvertebrate communities. Eight stations were selected to represent different land-use types including forestry, settlement,... -
Population dynamics and ecology of freshwater gastropods in the highveld and lowveld regions of Zimbabwe, with emphasis on schistosome and amphistome intermediate hosts
Item type: Journal Article • Journal: African Zoology • Authors: G. Chingwena --- Department of Paraclinical Veterinary Studies, Zimbabwe S. Mukaratirwa --- Department of Paraclinical Veterinary Studies, Zimbabwe M. Chimbari --- University of Zimbabwe Lake Kariba Research Station, Zimbabwe T. K. Kristensen --- Danish Bilharziasis Laboratory, Denmark H. Madsen --- Danish Bilharziasis Laboratory, DenmarkFrom November 1998 to October 2000, patterns of distribution and seasonal population fluctuations of snails and factors influencing them were investigated in six dams and six streams in the highveld region, and in nine dams in the lowveld region of... -
Effect of land use on water quality and phytoplankton community in the tropical Khami River in semi-arid southwest Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: T Dzinomwa --- Department of Environmental Science and Health, Faculty of Applied Science, Zimbabwe HGT Ndagurwa --- Department of Forest Resources and Wildlife Management, Faculty of Applied Science, ZimbabweThe water quality and phytoplankton community assemblage of the Khami River, a tropical river sub catchment in semi-arid southwest Zimbabwe impacted by agriculture and urban land use, were examined in March 2015. Conductivity, sulphates, total dissolved solids and salinity were... -
Improving the performance of the EPT Index to accommodate multiple stressors in Afrotropical streams
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: FO Masese --- Department of Fisheries and Aquatic Sciences, Kenya PO Raburu --- Department of Fisheries and Aquatic Sciences, KenyaThe EPT index (Ephemeroptera, Plecoptera and Trichoptera) may be skewed by the wide tolerance to multiple stressors of the Baetid, Caenid and Hydropsychid families, which affects the performance of the EPT index as an indicator of multiple stressors in aquatic... -
Habitat utilisation of Pseudobarbus afer and Sandelia capensis in headwaters of the Swartkops River, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Hannweg --- , South Africa SM Marr --- , South Africa LE Bloy --- , South Africa OLF Weyl --- , South AfricaHabitat degradation is one of the greatest threats to endemic freshwater fish in the Cape Fold Ecoregion. One habitat restoration strategy is the replication of critical habitat using artificial materials. In this paper, we evaluate the habitat occupancy of two... -
Relationship between sediment grain sizes and macroinvertebrate distribution along the Isiukhu River, western Kenya
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Emmanuel Mzungu --- Masinde Muliro University of Science and Technology, Kenya Anthony W Sifuna --- Masinde Muliro University of Science and Technology, Kenya William A Shivoga --- Masinde Muliro University of Science and Technology, KenyaThe current study investigated the relationship between sediment grain sizes and macroinvertebrate distribution along the Isiukhu River, a tropical stream in western Kenya. Ten sites in total were selected from the upstream, midstream and downstream areas. Sampling of sediments and... -
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...