OXYGEN DEMAND IN ICE COVERED LAKES AS IT PERTAINS TO WINTER AERATION¹

Abstract

Winterkill, the death of fish under ice due to oxygen deficiency, threatens hundreds of shallow lakes in the upper Midwest of the United States every winter. For decades, attempts have been made to prevent winterkill, usually through aeration, with mixed results. In large part, the failure of strategies to prevent winterkill can be linked to a lack of understanding of winter limnology and in particular, of oxygen dynamics under ice. Most winterkill lakes behave as closed systems with regard to oxygen. Consequently, the oxygen content of an ice and snow covered lake is essentially a function of the amount of initial storage and the rate of depletion. Should the stored oxygen be insufficient to prevent near anoxia before melting of the ice cover occurs, winterkill will result. Most oxygen consumption in ice covered lakes is due to bacterial respiration and chemical oxidation at the sediment/water interface, the remainder occurring in the water column. Oxygen consumption (and thus depletion) is a function of the velocity and oxygen concentration of the near sediment water. This is due to the fact that oxygen transport to the sediment is mediated by a diffusive boundary layer adjacent to the sediment surface. Winter oxygen depletion rates decrease when the oxygen concentration of the overlying water falls below about 3 mg/l. Aeration techniques which increase the oxygen concentration and velocity of the near‐sediment water also increase the oxygen consumption (depletion) rate.

Move or die: change in European catfish (Silurus glanisL.) behaviour caused by oxygen deficiency

“…leaf litter from trees, are also factors that contribute to reducing dissolved oxygen (hereafter DO) in the water column (Fast, 1994). The most serious manifestations of oxygen deficiency can occasionally cause fish mortality events known as winterkills (Ellis and Stefan, 1989;Danylchuk and Tonn, 2006). Changes in fish behaviour may also occur, such as changes in activity; however, these changes are difficult to detect without appropriate techniques such as telemetry (Bauer and Schlott, 2006).…”

“…However, the evaluation of such actions in natural habitats may be complicated without parallel monitoring of DO levels and because some of these actions in some cases may only increase the local chemical consumption of oxygen (e.g. by detritus decomposition), while DO in the water column does not increase significantly (Ellis and Stefan, 1989). The European catfish (Silurus glanis L.) is a common inhabitant of rivers, old oxbows and shallow alluvial lakes in the Eurasian temperate zone.…”

Dissolved oxygen transfer at the sediment‐water interface in a turbulent flow

“…DO is probably the single most important chemical parameter that is required to ensure the health of aquatic habitats [Schnoor, 1996]. Bottom sediments are a primary sink for DO in lakes, reservoirs, estuaries, and rivers [Ellis and Stefan, 1989 ]. These studies were concerned mainly with the effect of the mean velocity on bulk depletion of DO in the water column.…”

Vertical variation in magnitude and partitioning of oxygen demand in a contaminated sediment

“…4 50% in ice-covered lakes (Ellis and Stefan 1989), 50% in a marine system (Hanes and White 1968) and 42% in Lake Erie (Di Toro and Connolly 1980). The negative impacts of reduced oxygen saturation may be accompanied by those arising from the diffusion of reduced chemical species into overlying waters, the accumulation of such species having been observed in, for example, the Netherlands (Sweerts et al 1991) and the Manchester Ship Canal, UK (Boult and Rebbeck 1999).…”