How deep is Lake Victoria?
Lake Victoria
The lake exhibits eutrophic conditions. In 1990–1991, oxygen concentrations in the mixed layer were higher than in 1960–1961, with nearly continuous oxygen supersaturation in surface waters. Oxygen concentrations in hypolimnetic waters (i.e. the layer of water that lies below the thermocline, is noncirculating, and remains perpetually cold) were lower in 1990–1991 for a longer period than in 1960–1961, with values of less than 1mg per litre (< 0.4gr/cuft) occurring in water as shallow as 40 metres (130ft) compared with a shallowest occurrence of greater than 50 metres (160ft) in 1961. The changes in oxygenation are considered consistent with measurements of higher algal biomass and productivity.[23] These changes have arisen for multiple reasons: successive burning within its basin,[24] soot and ash from which has been deposited over the lake's wide area; from increased nutrient inflows via rivers,[25] and from increased pollution associated with settlement along its shores.