HR: 14:15h
AN: NB13C-04    [Abstracts]
TI: Land Use Patterns, Water Quality and Spawning Success of (Barbus) in the Mnembo River Catchment, Southern Africa
AU: * Delaney, L M
EM: b64lmd@mun.ca
AF: Memorial University of Newfoundland, Environmental Science Program Dean of Science, St. John's, NL A1B 3X7 Canada
AU: * Delaney, L M
EM: b64lmd@mun.ca
AF: WorldFish Center, PO Box 229, Zomba, Malawi
AU: Jamu, D M
EM: dmjamu@worldfishcenter.sdnp.org.mw
AF: WorldFish Center, PO Box 229, Zomba, Malawi
AU: Campbell, C E
EM: ccampbel@swgc.mun.ca
AF: Sir Wilfred Grenfell College, Memorial University of Newfoundland Environmental Science Department, Corner Brook, NL A2H 6P9 Canada
AB: Endorheic Lake Chilwa is one of the most productive lakes in Africa. High population density and agricultural practices in the Chilwa catchment have been linked to observed declines in the number and size of the commercially fished (Barbus) species. The Mnembo River is a major inflow into Lake Chilwa which has received little scientific study to date. In 2003/04, water quality and (Barbus) spp. abundance and distribution were monitored monthly in the Mnembo River to provide data for a lake management plan. Studies on smaller inflows into Lake Chilwa have implicated sediment yield, discharge, conductivity and total suspended solids (TSS) as influences on (Barbus) migration. Conductivity, pH and discharge were the most significant influences on (Barbus) spp. catch in the Mnembo River, while rainfall and water temperature were the most influential on (Barbus) spawning condition (Gonadosomatic Index). Sediment yield and soil loss were significantly lower in the Mnembo than in other catchments of Lake Chilwa because of markedly reduced agricultural land use. These results suggest that compared to Lake Chilwa's other catchments, the Mnembo is in good condition, however unsustainable land use practices will continue to increase until a management strategy for the Lake Chilwa watershed is implemented.
DE: 1803 Anthropogenic effects
DE: 1815 Erosion and sedimentation
DE: 1871 Surface water quality
DE: 9305 Africa
DE: 9902 NABS Student Award Applied Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly