Can a eutrophic lake be improved by increasing dissolved oxygen?

Question

I know that lower dissolved oxygen levels are a result of high nutrient levels in a productive (eutrophic) water body. I'm wondering if a system of pumping air through the lake, and thereby increasing oxygen levels, would mitigate the abundance of plant life? Or, perhaps, would the increased oxygen just encourage more productivity in the lake? I know nitrogen is a factor in eutrophication, and there is nitrogen in the air that would theoretically be pumped into the lake, but would the benefits of increased oxygen outweigh this?

Answer 1

Several things to keep in mind.  The nitrogen in the air is N2 gas, it is not available to algae or plants as a nutrient.  (To make fertilizer or a bioavailable nutrient compound, N2 must be "fixed" to form ammonia or nitrate (NH3- or NO3-.)

Second, bubbling air into ponds can be used on a limited scale, but it takes a lot of energy.  Bubbling air through water is not very efficient as a method to introduce O2 into water.  It is done in sewage treatment plants and in ponds where the cost is defrayed by some other value (like appearance, odor control, or fish production).  But it isn't practical as a means to improve water quality on a large scale in a large lake.