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Chemically, decreases in the oxygen content of lake water will likely occur. Warm water holds less oxygen than cold water. Additionally, the longer duration of summer stratification will increase the likelihood of oxygen depletion in lower layers of the lake water. Such oxygen depletion occurs fairly regularly in the Northeast Arm of the lake.
Predicting biological changes in Lake Champlain as a result of global warming means attempting to integrate the impacts of all the physical and chemical change on each species and speculating about how they will affect that species’ interactions with other species. Fish will need to adapt because spawning in many species is triggered by optimum temperatures. Earlier warming will mean earlier spawning. Perhaps more importantly, available habitat for cold-water species like trout and salmon could decrease, while habitat for warm-water species like bass could increase.
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http://www.lakechamplaincommittee.org/lcc-at-work/global-warming-lake-champlain/