The Compass of Light, Volume 4: Poetics in the Great Invocation
Shining Light on Cladophora in the Great LakesShining Light on Cladophora in the Great Lakes Anika...
Transcript of Shining Light on Cladophora in the Great LakesShining Light on Cladophora in the Great Lakes Anika...
Shining Light on Cladophora in the Great LakesAnika Kuczynski and Martin T. Auer
Civil and Environmental Engineering, Great Lakes Research Center
Lake Erie
Photo courtesy: Scott Higgins
Unsightly Problems
Investigating Phosphorus
Nearshore Management Approach
LakeOntario
Clogged water intakes
Beach fouling
Habitat for pathogens
Great Lakes Water Quality Protocol (2012)
We cannot manage light, but we can manage phosphorus.
1) To achieve the Lake Ecosystem Objective of “[maintaining] the levels of algal biomass below the level constituting a nuisance
condition,” we must define nuisance conditions.
2) To avoid nuisance conditions, the Protocol demands development of “Substance Objectives for phosphorus concentrations for
nearshore waters […].”
We propose development of a phosphorus standard based on stored P, representing growth potential due to phosphorus
availability, which can be related to soluble reactive phosphorus concentrations in nearshore waters using the Great Lakes
Cladophora Model (Tomlinson et al. 2010).
The Golden Horseshoe region along the northwestern shore of Lake Ontario is heavily impacted by urban discharges.
Stored P in algae samples taken along the Ajax, ON nearshore reveal that algae growing in close proximity to a wastewater treatment
plant outfall have an elevated stored P content, which indicates an increased production potential.
0.00
0.04
0.08
0.12
0.16
0.20
79
.16
47
79
.15
71
79
.14
96
79
.14
69
79
.14
17
79
.13
20
79
.12
41
79
.11
94
79
.10
94
79
.09
48
79
.07
15
79
.06
02
79
.04
82
79
.04
05
79
.02
75
79
.02
10
79
.01
04
79
.00
48
78
.99
38
78
.98
16
78
.97
19
78
.96
68
78
.96
02
78
.94
92
78
.92
80
78
.91
54
78
.90
23
78
.89
50
78
.00
78S
tored P
(as %
dry w
eig
ht)
Longitude (Decimal Degrees)
Duffin Creek
WPCPHighland Creek
WPCP
Corbett Creek
WPCP
Investigating Light
The resurgence in Cladophora
beach fouling is due to an
increase in colonizable “real
estate” through improved light
conditions at locations where
phosphorus (P) is provided.
Bottom detection depth limit (visibility off shore) and
bottom classification at Ajax in 1983 and 2011 (Landsat
data processing by the Michigan Tech Research Institute).
Photo source: http://www.100thmeridian.org/photobank/US_Fish_and_Wildlife_Service/Zebras/JustMussels.jpg
Invaders of the 1990s:
Filter feeding dreissenid mussels remove light-
disturbing particulate from the water column.
Apart from favorable light conditions, Cladophora requires phosphorus to grow.
Ajax, ON
Image sources: Google Earth and Google Maps
Reference: Tomlinson, Lisa M., et al. "The Great Lakes Cladophora model: development, testing, and application to Lake Michigan." Journal of Great Lakes Research 36.2 (2010): 287-297.
This work was supported in part by Gowling Lafleur Henderson LLP, based in Toronto, ON.