Abstract/Summary

the prospect of using fallowing as an ecosystem managementmeasure to restore ecosystem functions in disturbed aquatic envi-ronments under cage culture was evaluated in this study. the cageaquaculture site in the southeast arm of lake Malawi was studiedfollowing the abandonment of cage aquaculture activities in 2022after 18 years of operation. a hydrolab ctD Ms5 series probe wascast at each station to a maximum depth to collect electronic dataand provide in situ depth profiles of temperature, dissolved oxy-gen, oxygen saturation, ph and salinity. chlorophyl-extraction wasdone using a mixture of acetone and methanol and analyzed on aturner series 10 fluorometer. the study found that physical-chemicalparameters such as temperature, ph, ammonia, turbidity and dis-solved oxygen were not significantly different (p > 0.05) across thecage and non-cage sites and between seasons. however, ammonialevels recorded in this study were lower than the values reportedduring the cage culture operations period, an indication that somerecovery processes are happening at the site. chlorophyl a levelwas found to be insignificantly higher in cage and non-cage sites(p > 0.0.5) and significantly different between season (p < 0.05). highlevels of chl-a observed in this study are independent of cageaquaculture but might be linked to external inputs associated withtributaries as they collectively drain into the lake. chl-a was foundto be significantly and directly correlated to temperature, followedby total suspended solids and ph. Overall, the site is undergoingrecovery with respect to the abandonment, but the effect ismasked by external inputs of nutrients into the lake. although thestudy confirmed the oligotrophic status of the lake, the increasinglevels of chl-a are alarming and calls for inclusion of watershedmanagement in agriculture and environmental management pro-gramming to sustainably safeguard the health of the lake.