Horne, A. J.. Ecological Engineering Group,
, . J.. ,
NITROGEN AND PHOSPHORUS LIMITATION IN LAKES: A BEE KEEPERS APPROACH
Limnologists ascribe the limitation of algal growth in lakes to one element, phosphorus. The absolutist nature of this statement is partially a limno-political judgement and partially a geographical accident. However, the battles with the Detergent Manufacturers Association were won long ago and some limnologists work outside the northern temperate region which nurtured the mind set of most ALSO members, myself included. Phosphorus-diversion from lakes has had well-publicized spectacular successes, but also some less discussed failures. Is has become obvious that not all eutrophication problems can be solved by P-control alone. Despite confusion between (annual) yield and (daily) growth limitation, the advent of the curious term co-limitation and over-use of N:P ratios, something is still not quite right in biostimulation theory. Since experiments with natural phytoplankton show growth limitation by N in half of US lakes, a new paradigm is needed where both N and P are controlled in sewage and agricultural discharges. Now that US federal courts have classified the engineer's approach as more like a bee keeper(s) it is time for an ecological engineering solution to eutrophication. If you don't give bees what they need, there is no honey. Perhaps we need to find out what our lakes really need to solve eutrophication. New techniques of dentrification in waste treatment plants and wetlands provide a practical method to achieve N-removal, as was devised for P-removal decades ago.
Day: Thursday, Feb. 4
Location: Sweeney Center