Project ID: 2006ME86B
Title: Does food-web structure mediate landscape-scale responses of Maine lakes to nutrient enrichment?
Project Type: Research
Start Date: 01/07/2006
End Date: 06/30/2008
Congressional District: Second
Focus Categories: Ecology, Surface Water, Non Point Pollution
Keywords: Eutrophication, Lakes, Zooplankton, Ecosystems
Principal Investigators: Webster, Katherine; Bacon, Linda; Wilson, Laura R.
Federal Funds: $9,996
Non-Federal Matching Funds: $74,306
Abstract: Unsightly algal blooms that reduce water clarity are one of the most noticeable consequences of lake eutrophication. Chlorophyll a, a measure of algal biomass, tends to increase with total phosphorus; however there is considerable scatter around this relationship. Cladoceran body size, which is directly related to grazing efficiency, may explain some of the scatter. Lakes with zooplankton communities dominated by larger cladocerans, such as Daphnia, tend to be clearer and, thus, more resilient to the effects of nutrient enrichment. The objectives of this proposed study are to (1) assess indices of cladoceran body size that best explain deviations from the relationship between nutrient concentration and water clarity in Maine lakes; (2) use cladoceran resting eggs in sediment cores to assess the relative stability of lakes with different histories of nutrient enrichment; and (3) develop and evaluate outreach tools on the subject of lake foodwebs. The ultimate goal is to demonstrate that maintenance of healthy, thus resilient lake food webs needs to accompany nutrient controls for effective lake management and sustainable lake use.
Progress/Completion Report, PDF