SS3.12 Large Scale Ecosystem Manipulations
Date: Thursday, June 13, 2002
Time: 2:15:00 PM
Location: Carson C
 
BodalyRA, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, bodalyd@dfo-mpo.gc.ca
Blanchfield, P, J, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, blanchfieldp@dfo-mpo.gc.ca
Hesslien, R, H, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, hessleinr@dfo-mpo.gc.ca
Kasian, S, E, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, kasians@dfo-mpo.gc.ca
Kidd, K, A, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, kiddk@dfo-mpo.gc.ca
Mills, K, H, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, millsk@dfo-mpo.gc.ca
Paterson, M, J, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, patersonm@dfo-mpo.gc.ca
Podemski, C, L, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, podemskic@dfo-mpo.gc.ca
Rudd, J, W, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, ruddj@dfo-mpo.gc.ca
Turner, M, A, Experimental Lakes Area, Fisheries and Oceans, Winnipeg, Canada, turnermi@dfo-mpo.gc.ca
 
WHOLE ECOSYSTEM MANIPULATIONS AT THE EXPERIMENTAL LAKES AREA, NORTHWESTERN ONTARIO, CANADA; THE POWER OF WHOLE-LAKE EXPERIMENTS
image
Whole ecosystem manipulations have been carried out at the Experimental Lakes Area (ELA) for over 30 years. Whole lake experiments have the primary advantage of realism over smaller-scale (e.g. laboratory or mesocosm) experiments by inclusion of complete ecosystems (including food webs) and by conducting the experiments over long enough time scales to allow slow processes to take effect. Food chain effects have been particularly important in the interpretation of the results from ELA studies. Whole lake experiments suffer from lack of replication and true controls; reference systems are important to interpret natural variation. Other limitations include: difficulties in transferring results from small to larger lakes, the need for large multi-disciplinary teams (communication and decision making can be problematic), costs are high (and assembling funding often difficult), and not all subjects are amenable to experimentation. Whole lake experiments at ELA have evolved from those concerned mainly with nutrients and primary productivity to those that include the whole community and frequently the watershed as well.