Multiple Stressors of Lakes of Muskoka: Past and Current Challenges

Multiple Stressors of Lakes of Muskoka:

Past and Current Challenges

Dr. Norman Yan

We have solved many environmental problems

Eutrophicationcaused by excessive phosphorus loading

Acid Raincaused mainly by sulphur dioxide emissions

Loss of Birdsdue to DDT and other chlorinated pesticides

Lead Pollutionfrom leaded gasoline

Ozone Depletioncaused by CFCs

Cosmetic Use of Pesticides

Eutrophication

EUTROPHICATIONAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Recovery of Gravenhurst Bay from Eutrophication

EUTROPHICATIONAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Acid Rain

EutrophicationACID RAINDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

We Have Reduced SO2 Emissions


Acidity Has Fallen


5 6 7

5

6

7

p

H

i

n

2

0

0

4

/

5

pH in 1980s

DDT Levels Have Fallen Everywhere

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals


DDT in Breast Milk in North America

EutrophicationAcid RainDDTLEADOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Environmental Lead Levels Have Plummeted


and Blood Lead Levels Have Fallen in Response

Toxic level


Toxic level

Mean Lead Concentrations (ppm) in Toronto Maple Tree Foliage1971 - 2004

78.2

60.556.4 55.2

50.0

24.422.3

24.320.2 21.8

3.2 1.7 1.3 1.3 1.61.0 0.9 1.3 0.7 0.90

10

20

30

40

50

60

70

80

90

0 to 5 5 to 10 10 to 15 15 to 20 20 to 30Km from City Centre

L

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Pb 1971 Pb 1981 Pb 1991 Pb 2004

Mean Lead Concentrations (ppm) in Toronto Maple Tree Foliage1971 - 2004

78.2

60.556.4 55.2

50.0

24.422.3

24.320.2 21.8

3.2 1.7 1.3 1.3 1.61.0 0.9 1.3 0.7 0.90

10

20

30

40

50

60

70

80

90

0 to 5 5 to 10 10 to 15 15 to 20 20 to 30Km from City Centre

L

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Pb 1971 Pb 1981 Pb 1991 Pb 2004

EutrophicationAcid RainDDTLeadOZONE DEPLETIONLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Global CFC Production (t/year) & Release Plummeted

EutrophicationAcid RainDDTLeadOzone DepletionLAWN PESTICIDESDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

And Behind My Bracebridge Home

EUTROPHICATIONACID RAINDDTLEADOZONE DEPLETIONLAWN PESTICIDESDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Solving these Environmental Problems Required:

Knowledgeproblem recognition, cause identification, evaluation of possible solutions

Willpublic engagement, ie education and marketing

Actionpolicy change, reasoned intervention

Re-assessmentsto prove success

What are the current environmental issues Facing Muskoka?

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDEVELOPMENTMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Certainly Ongoing Pressures from Development

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDEVELOPMENTMercuryClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Stress Linked to Overall Development in Muskoka

2014 Muskoka Watershed Report Card

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMERCURYClimate ChangeCalcium declineRoad SaltInvadersNovel chemicals

Mercury Pollution Remains a Threat to Loons and Other Fish-Eating Wildlife

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryCLIMATE CHANGECalcium declineRoad SaltInvadersNovel chemicals

The Climate is Changing: Departure of Annual Temperature from the 1950-1980 Mean

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCALCIUM DECLINERoad SaltInvadersNovel chemicals

Calcium Levels are Fallingie. Plastic Lake near the Frost Centre

1975 1980 1985 1990 1995 2000 2005 2010 20151.0

1.2

1.4

1.6

1.8

2.0

2.2

I

c

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-

f

r

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s

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Year

2004

Proposed Ca thresholds for Daphnia:

Ashforth & Yan: 1.5 mg/LCairns et al: 1.3 to 1.7 mg/LDeSellas et al: 1.5-2 mg/L


All Life Needs Calcium (Ca)


Stress Linked to Calcium Decline in Muskoka


EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineROAD SALTInvadersNovel chemicals

1.5 Million Tonnes of Salt are used on Canadas Roads


Chloride Levels Have Risen in Lakes of MuskokaNear Highways

0 50 100 150 200

0

20

40

60

80

100

C

l

(

m

g

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L

)

Rank of Cl

Jevins Lake

Ada & Webster lakes

Wolfkin Lake

LC50 for Cl(0.2 mg C/L food)

Rank of Lake by Cl Level


All of the Lakes with High Cl are Beside Winter-Maintained Highways ie. Jevins Lake


And Road Salt is More Damaging in Nutrient-poor Lakes

y = 251.95x - 23.59R = 0.9323

y = 308.55x - 29.71R = 0.9118

0

50

100

150

200

250

300

0 0.2 0.4 0.6 0.8 1 1.2

1

4

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L

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Food (mg C/L)

LC50 (CaCl2)LC50 (NaCl)

CWQG(120 mg Cl-/L)

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltINVADERSNovel chemicals

Stress Linked to Invading Species in Muskoka

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltINVADERSNovel chemicals


Novel chemicals are appearing in Ontario lakes:

Pharmaceuticals

Flame retardants

Cosmetics

Plasticizers

Nano-materials

Micro-plastics

EutrophicationAcid RainDDTLeadOzone DepletionLawn pesticidesDevelopmentMercuryClimate ChangeCalcium declineRoad SaltInvadersNOVEL CHEMICALS

In summary

Many issues have been resolved

Eutrophication

Acid rain

Ozone depletion

Smelter pollution

Lead pollution

Chlorinated pesticides

Lawn pesticides

But others are worsening

Calcium decline

Invading species

Road salt

Climate change

Development pressures

Novel chemicals

Which of the Current Threats May be Helped by Local Action?

Calcium decline (in part)

Invaders (in part)

Road salt

Climate change (in part)

Development pressures

Novel chemicals

Can we solve environmental problems?

Yes

Will we solve these developing problems?

???

Documents

Multiple Stressors of Lakes of Muskoka: Past and Current Challenges