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Water Chemistry
By Lucas Kirby, Cynthia Watson, Meghan Dye and Stephanie
Johnson
Importance of Phosphorus in Lakes
Limiting nutrient in freshwater systemsRedfield ratioHigh concentrations may be indicative of eutrophication
Oneida LakeLargest land-locked lake in NYSShallow, well mixed lakeMean depth of 6.8mEutrophicOver 100 species of algae
Onondaga LakeOne of the most polluted lakes in the U.S.4.6 mi long, 1 mi wide~10.6 m deepSyracuse METRO plant contributes 20% of annual inflowHypereutrophic(>100 µg/L)
Green LakeSmall surface area (glacial plunge pool), formed by waterfall~52 m deepOligotrophicHard waterMeromictic Permanent chemocline
Arbutus and Rich LakesMax. depth:
Arbutus: 8 mRich: 18 m
Area Arbutus: 49 haRich: 160 ha
Archer Creek Catchment (130 ha) drains into Arbutus Lake
MethodsCollecting Samples
Kemmerer bottle1L from epi-, meta- and
hypo- Mixed Reagent- in specific order (for 150ml)
Ammonium molybdate solution- 30mlSulfuric Acid- 75mlAscorbic Acid- 30mlPotassium antimonyl-tartrate solution- 15ml
Standard SolutionDuplicate solutions 50ml of DI waterColor blank5ml Mixed Reagent
Unknown SolutionTwo Replicates- 50 ml sample5ml Mixed Reagents
Calculate for Unknown Phosphorus
Average ReplicatesGraph- Standard Absorbance v. Standard ConcentrationCalculate Slopeμmol-1-1 = (sample abs-reagent blank abs-color blank abs)* slope
ResultsWater Chemistry: Phosphorus Concentration
0
5
10
15
20
25
30
35
0 5 10 15
Phosphorus Concentration (uM)
De
pth
(m
)
Arbutus
Green
Oneida
Onondaga
Rich
Discussion Oneida Lake
Second highest phosphorus level.Measured lake depth around 6 metersLake mixes through summer. Oxygenated hypolimnion
Water Chemistry: Phosphorus Concentration Oneida Lake
0
1
2
3
4
5
6
7
0 0.5 1 1.5 2
Phosphorus Concentration (uM)
Dep
th (
m)
DiscussionOnondaga Lake
Highest level of P.Anoxic bottom waters Iron releases P. P Decreases with decrease depth.
Water Chemistry: Phosphorus Concentration Onondaga Lake
0
5
10
15
20
0 5 10 15
Phosphorus Concentration (uM)
Dep
th (
m)
Discussion Green Lake
Lowest P level of all lakesLowest P epilimnion, organisms use what ever P available.Increases approx. at thermoclineDecreases again at hypolimnion Increase below chemocline
Water Chemistry: Phosphorus Concentration Green Lake
0
5
10
15
20
25
30
35
0 0.2 0.4 0.6 0.8 1 1.2 1.4
Phosphorus Concentration (uM)
Dep
th (
m)
Discussion Arbutus Lake
Shallow mixed lakeLow productivityOxygenated hypolimnion
Water Chemistry: Phosphorus Concentration Arbutus Lake
0
2
4
6
8
0 0.2 0.4 0.6 0.8 1
Phosphorus Concentration (uM)
Dep
th (
m)
Discussion Rich Lake
Medium depth but mixes often. Low productivity Oxygenated hypolimnion.
Water Chemsitry: Phosphorus Concentration Rich Lake
0
2
4
6
8
10
12
0 0.5 1 1.5 2
Phosphorus Concentration (uM)
Dep
th (
m)
Other Measurements-Nitrogen-Silica-Iron, Fe+3
ReferencesCirmo, Chris Ph.D. 2005. http://web.cortland.eduCouncil on hydrologic systems science. Biogeochemical and Hydrological Research at the Huntington Forest. www.esf.edu/hss/HuntingtonForestOverview.htm New York State Parks, Recreation and Historic Preservation. 2005. http://nysparks.state.ny.usOneida Lake Association. 1998. http://web.a-znet.com/~ola/index.htmlOnondaga Lake Improvement Project. 2005. http://www.lake.onondaga.ny.us/index.htmUpstate Freshwater Institute. 2005. http://www.upstatefreshwater.org/index.html
