TEAMTEAM Project: Project: TTrends in rends in EEutrophication and utrophication and AAcidification in cidification in

the the MMaritimesaritimes

Overview:Overview:

• 5 year NSERC Strategic Grant (2002 – 2007)5 year NSERC Strategic Grant (2002 – 2007)

• Investigate water quality issues in Nova Scotia and Investigate water quality issues in Nova Scotia and Southern New BrunswickSouthern New Brunswick

• Combine paleolimnology and biogeochemical modelingCombine paleolimnology and biogeochemical modeling

• http://biology.queensu.ca/~pearl/maritimeshttp://biology.queensu.ca/~pearl/maritimes

Overview:Overview:

Main projects: Main projects:

• Lake acidification in Nova Scotia and southern NB Lake acidification in Nova Scotia and southern NB • NS Brook Trout Lake ProjectNS Brook Trout Lake Project• Impacts of development on:Impacts of development on:

King’s County lakes King’s County lakes Cape Breton Highlands Park lakes Cape Breton Highlands Park lakes Halifax Metro area lakesHalifax Metro area lakes

PartnersPartners

Part I: Surface-water Acidification Part I: Surface-water Acidification

Decrease in pH of lakes and rivers due to inputs Decrease in pH of lakes and rivers due to inputs of strong acid ions.of strong acid ions.

Main Cause:Main Cause:

Industrial emissions of sulphur and nitrogen Industrial emissions of sulphur and nitrogen oxidesoxides

So: So: • Lowers pH in soils and surface Lowers pH in soils and surface

waterswaters

• Mobilizes metals in soils Mobilizes metals in soils e.g. Hg, Cd, etc.e.g. Hg, Cd, etc. Monomeric Al Monomeric Al

−Binds to gills (e.g., trout)Binds to gills (e.g., trout)

Additionally:Additionally:

• Coastal AreasCoastal Areas: : ClCl-- + H + H22O O HCl HCl

Photo: CBC News

Surface-water Acidification Surface-water Acidification

Acidic Deposition: Acidic Deposition: CanadaCanada• 43% of Canada sensitive to acid 43% of Canada sensitive to acid

depositiondeposition ~ 1 million lakes > 1 ha~ 1 million lakes > 1 ha

• Many pH < 6.0 (acid)Many pH < 6.0 (acid)

• Studies (1970-1980’s)Studies (1970-1980’s)

• SOSO22 emission restrictions (1990’s) emission restrictions (1990’s)

• Today: Many lakes still acidToday: Many lakes still acid

Recovery?Recovery? What were pre-impact (background) What were pre-impact (background) conditions? conditions?

Photo: B. Ginn

Nova Scotia: Nova Scotia: Acidification Acidification • Environment Canada’s LRTAP Environment Canada’s LRTAP

ProgramProgram

• Semi-annual monitor 72 lakesSemi-annual monitor 72 lakes

- Southwest – 1983- Southwest – 1983

- North – 1989- North – 1989

• Monitored Monitored AFTERAFTER possible possible acidificationacidification

• Sulphate deposition:Sulphate deposition:

- Current: 10.5 kg/ha/yr - Current: 10.5 kg/ha/yr (10-16% marine sources)(10-16% marine sources)

- Highest: 21 kg/ha yr (1981)- Highest: 21 kg/ha yr (1981)

Need pre-impact Need pre-impact environmental data!!!!environmental data!!!!

Nova Scotia: Study Nova Scotia: Study AreasAreas• 51 lakes sampled51 lakes sampled

• YarmouthYarmouth

• BridgewaterBridgewater

• Kejimkujik National ParkKejimkujik National Park

• Eastern Shore at Ecum SecumEastern Shore at Ecum Secum

• Cape Breton Highlands National ParkCape Breton Highlands National Park

““High” SOHigh” SO442-2- deposition deposition

Different land use?Different land use?

The “Halifax” effect?The “Halifax” effect?

““Low” SOLow” SO442- 2-

depositiondeposition

Research ObjectivesResearch Objectives

• What do diatoms indicate about present conditions? What do diatoms indicate about present conditions? Diatom – Environment Calibration SetDiatom – Environment Calibration Set

• Have there been changes in diatom Have there been changes in diatom assemblages?assemblages?

“ “Before – After” analysis (current vs pre-Before – After” analysis (current vs pre-impact)impact)

• When did changes occur? Cause?When did changes occur? Cause? Study 14 lakes in detail for decadal changesStudy 14 lakes in detail for decadal changes

Kejimkujik: “high” SOKejimkujik: “high” SO442-2- deposition deposition

Cape Breton: “low” SOCape Breton: “low” SO442-2- deposition deposition

Calibration: Inferring Current Calibration: Inferring Current ConditionsConditions• 51 Nova Scotia lakes, all acidic lakewater pH51 Nova Scotia lakes, all acidic lakewater pH

0

5

10

15

20

4 5 6 7 8 9

Lakewater pH:Lakewater pH:

4.5 – 6.84.5 – 6.8

Problem? All lakes are “acidic”Problem? All lakes are “acidic”

Ecological responses of diatoms to pH are Ecological responses of diatoms to pH are probably not fully describedprobably not fully described

Calibration Calibration SetSet

0

10

20

30

40

50

60

4 5 6 7 8

• Combined: 487 LakesCombined: 487 Lakes

• PA PA NS NS

• pH: 4.3 – 8.7pH: 4.3 – 8.7

• 989 diatom taxa989 diatom taxa

• most were raremost were rare

• 1% in 10 lakes1% in 10 lakes

• 176 diatom taxa176 diatom taxapHpH

Nu

mb

er

of

lake

sN

um

ber

o

f la

kes

Problem?Problem?

Distribution weighted to pH = 7-8Distribution weighted to pH = 7-8

Calibration Calibration SetSet

0

10

20

30

40

50

60

4 5 6 7 8

• ““Box” distributionBox” distribution

• 383 lakes383 lakes

• No weighting toward No weighting toward pH = 7-8pH = 7-8

pHpH

Nu

mb

er

of

lake

sN

um

ber

o

f la

kes

Calibration: Sites vs EnvironmentCalibration: Sites vs Environment

-1.5 1.0

-1.0

1.0

Colour

DOC

Alkalinity

pH

Al

Ca

Elevation

-1.5 1.0

-1.0

1.0

Colour

DOC

Alkalinity

pH

Al

Ca

Elevation Adirondacks

N. New England

Poconos

EMAP

Nova Scotia

Calibration: Species vs Calibration: Species vs EnvironmentEnvironment

-1.5 1.0

-1.0

0.8

ColourDOC

Alkalinity

pH

AlCa

Elevation

-1.5 1.0

-1.0

0.8

ColourDOC

Alkalinity

pH

AlCa

Elevation

AcidicAcidicAlkalineAlkaline

Before – After Before – After Analysis:Analysis:Evaluate current pH vs pre-industrial pHEvaluate current pH vs pre-industrial pH

Photo: K. Rühland

““Top” (0.0-0.5 cm) = Present-Top” (0.0-0.5 cm) = Present-dayday

““Bottom” (15.0-15.25 cm) = Pre-Bottom” (15.0-15.25 cm) = Pre-industrialindustrial

- 100-150 yrs B.P.- 100-150 yrs B.P.

““Sub-bottom” (25.0-25.25 cm)Sub-bottom” (25.0-25.25 cm)

- 200-300 yrs B.P.- 200-300 yrs B.P.

- set background pH - set background pH changeschanges

Before – After Analysis:Before – After Analysis:

Photo: Google Earth

pH change < -0.2pH change < -0.2

pH change > -0.2pH change > -0.2

YarmoutYarmouthhKejimkujik N.P.Kejimkujik N.P.

BridgewateBridgewaterr

Ecum Ecum SecumSecum

Cape Breton Cape Breton Highlands Highlands

N.P.N.P.

HalifaxHalifax

Top – Bottom: SouthwestTop – Bottom: Southwest

Why only acidification in Kejimkujik?Why only acidification in Kejimkujik?

• Same: bedrock, soils, SOSame: bedrock, soils, SO442-2- deposition deposition

BUT:BUT:

• Differences in watershed disturbance Differences in watershed disturbance

Kejimkujik = protectedKejimkujik = protected

Bridgewater / Yarmouth Bridgewater / Yarmouth developed developed

• Kejimkujik had lower pre-impact lakewater pHKejimkujik had lower pre-impact lakewater pH

What was timing of changes in these What was timing of changes in these areas?areas?

Detailed Core AnalysisDetailed Core Analysis

• Study changes at decadal Study changes at decadal scalescale

timing of timing of acidificationacidification

• Cape Breton Highlands National Cape Breton Highlands National ParkPark::

“ “low” SOlow” SO442-2- deposition deposition

6 lakes6 lakes

• Kejimkujik National ParkKejimkujik National Park::

“ “high” SOhigh” SO442-2-

depositiondeposition

8 lakes8 lakes

Warren Lake (Cape Warren Lake (Cape Breton)Breton)

2002

1995

1975

1955

1935

1905

1875

1855

~1830

0 0 20 0 20 0 20 0 20 0 0 20 0 5.5 6.0 6.5 7.0 -3.0-1.01.03.0

2002

1995

1975

1955

1935

1905

1875

1855

~1830

0 0 20 0 20 0 20 0 20 0 0 20 0 5.5 6.0 6.5 7.0 -3.0-1.01.03.0

• Low DOC: 4.2 mg/LLow DOC: 4.2 mg/L• Current pH: 6.5Current pH: 6.5• Inferred pH varied: Inferred pH varied:

6.0 6.0 5.8 5.8 ~ 1830 - 2002~ 1830 - 2002

Photo: B. Ginn, NS DNR

Dundas #4 (Cape Dundas #4 (Cape Breton)Breton)

2002

1995

1975

1955

1935

1905

1850

0 20 40 60 80

Aulaco

seira

lirata

0 20

Aulaco

seira

ambig

ua

0 20 40

Aulaco

seira

perg

labra

0 20

Aulaco

seira

dista

ns

0

Aulaco

seira

cras

sipun

tata

0 20

Melo

sira

aren

tii

0 20

Fragil

arifo

rma

exigu

a

5.0 5.5 6.0 6.5

Diatom

-infe

rred

pH

-3.0 -1.0 1.0 3.0

PCA-Axis

1 S

ite S

core

s

2002

1995

1975

1955

1935

1905

1850

0 20 40 60 80

Aulaco

seira

lirata

0 20

Aulaco

seira

ambig

ua

0 20 40

Aulaco

seira

perg

labra

0 20

Aulaco

seira

dista

ns

0

Aulaco

seira

cras

sipun

tata

0 20

Melo

sira

aren

tii

0 20

Fragil

arifo

rma

exigu

a

5.0 5.5 6.0 6.5

Diatom

-infe

rred

pH

-3.0 -1.0 1.0 3.0

PCA-Axis

1 S

ite S

core

s

• High DOC: 11.0 mg/LHigh DOC: 11.0 mg/L• Current pH: 5.2Current pH: 5.2• Inferred pH varied: Inferred pH varied:

5.8 5.8 5.7 5.7 pre-1600 – 2002pre-1600 – 2002

• No acidification trendNo acidification trend

Photo: B. Ginn

Beaverskin Lake Beaverskin Lake (Kejimkujik)(Kejimkujik)

• ClearwaterClearwater• Low DOC: 2.1 mg/LLow DOC: 2.1 mg/L• Current pH: 5.5Current pH: 5.5• Inferred pH change: Inferred pH change:

6.4 6.4 5.3 5.3 ~ 1925 - 1930~ 1925 - 1930

2002

1995

1975

1955

1935

1905

1885

1865

0 20 0 20 0 20 0 20 0 20 0 20 40 5.0 5.5 6.0 6.5 -2.0-1.00.01.02.0

2002

1995

1975

1955

1935

1905

1885

1865

0 20 0 20 0 20 0 20 0 20 0 20 40 5.0 5.5 6.0 6.5 -2.0-1.00.01.02.0

CyclotellaCyclotella FrustuliaFrustuliaPhoto: B. Ginn, NS DNR

Pebbleloggitch Lake Pebbleloggitch Lake (Kejimkujik)(Kejimkujik)

• High DOC: 11.6 mg/LHigh DOC: 11.6 mg/L• Current pH: 4.9Current pH: 4.9• Inferred pH changeInferred pH change: :

5.6 5.6 5.0 5.0 ~ 1950~ 1950

2002

1995

1975

1955

1935

1905

1875

1855

0 20 40

Asterio

nella

ralfs

ii var

amer

icana

>45

um

0

Tabell

aria

flocc

ulosa

strain

III

0

Tabell

aria

quad

risep

tata

0 20

Aluaco

seira

cras

sipun

ctata

0

Aulaco

seira

perg

labra

0 20

Aulaco

seira

dista

ns

0 20 40

Aulaco

seira

lirata

4.5 5.0 5.5 6.0

Diatom

-infe

rred

pH

-3.0 -1.0 1.0 3.0

PCA-Axis

1 S

ite S

core

s

2002

1995

1975

1955

1935

1905

1875

1855

0 20 40

Asterio

nella

ralfs

ii var

amer

icana

>45

um

0

Tabell

aria

flocc

ulosa

strain

III

0

Tabell

aria

quad

risep

tata

0 20

Aluaco

seira

cras

sipun

ctata

0

Aulaco

seira

perg

labra

0 20

Aulaco

seira

dista

ns

0 20 40

Aulaco

seira

lirata

4.5 5.0 5.5 6.0

Diatom

-infe

rred

pH

-3.0 -1.0 1.0 3.0

PCA-Axis

1 S

ite S

core

s

AulacoseiAulacoseirara

AsterionellaAsterionella

•15 – 20 years AFTER 15 – 20 years AFTER BeaverskinBeaverskin

•DOC = buffer?DOC = buffer?

Photo: B. Ginn, NS DNR

Acidification: SummaryAcidification: Summary

• YarmouthYarmouth

• BridgewaterBridgewater

• Kejimkujik National ParkKejimkujik National Park

• Eastern Shore at Ecum SecumEastern Shore at Ecum Secum

• Cape Breton Highlands National ParkCape Breton Highlands National Park

““High” SOHigh” SO442-2-

No acidification No acidification

Land use? Background pH?Land use? Background pH?

AcidificationAcidification

The “Halifax” effect?The “Halifax” effect?

““Low” SOLow” SO442- 2-

no acidificationno acidification

““High” SOHigh” SO442-2-

Acidification (mostly)Acidification (mostly)

Part II: EutrophicationPart II: Eutrophication

• World’s most widespread water quality World’s most widespread water quality issueissue

• Increased lake productivity due to inputs of Increased lake productivity due to inputs of limiting nutrients:limiting nutrients: NitrogenNitrogen PhosphorusPhosphorus

• Algal blooms (algae + cyanophytes)Algal blooms (algae + cyanophytes)• Decreased water quality, taste and odour issues, Decreased water quality, taste and odour issues, hypolimnetic anoxia (fish kills)hypolimnetic anoxia (fish kills)

• NS Brook Trout Sport Fishery worth:NS Brook Trout Sport Fishery worth:

• $57 million$57 million (2002) (2002)

• ~ 400 lakes stocked annually~ 400 lakes stocked annually

• Need cool, well-oxygenated waterNeed cool, well-oxygenated water

- Dissolved O- Dissolved O22 over 5.0 mg/L over 5.0 mg/L

• NS Hypolimnion Project:NS Hypolimnion Project:

- 25 year study in bottom O- 25 year study in bottom O22 in 20 in 20 lakes lakes

- Originally: 11 “good” habitat, 9 - Originally: 11 “good” habitat, 9 “poor”“poor”

- Now: all 20 “poor” trout habitat- Now: all 20 “poor” trout habitat

Brook Trout LakesBrook Trout Lakes

“… “… it is not possible to determine to what extent, if any, it is not possible to determine to what extent, if any, the trophic status of these lakes has changed.” the trophic status of these lakes has changed.” – NS – NS Hypolimnion ProjectHypolimnion Project

Brook TroutBrook Trout

Salvelinus fontinalisSalvelinus fontinalis

• Cold-water salmonid native to Nova ScotiaCold-water salmonid native to Nova Scotia• Limiting factor: suitable cold-water summer habitatLimiting factor: suitable cold-water summer habitat• Require DO ≥ 50% saturationRequire DO ≥ 50% saturation

QuestionsQuestions

• Have hypolimnetic oxygen levels decreased in the brook Have hypolimnetic oxygen levels decreased in the brook trout lakes?trout lakes?

• In those lakes that do show change, when did species In those lakes that do show change, when did species assemblage change and inferred oxygen decreases occur assemblage change and inferred oxygen decreases occur and by how much?and by how much?

• And if so, are there identifiable environmental or And if so, are there identifiable environmental or anthropogenic causes for this decrease?anthropogenic causes for this decrease?

Paleo-indicators: ChironomidsPaleo-indicators: Chironomids

Chironomids (larval stage)Chironomids (larval stage)• Order Diptera, family Order Diptera, family

Chironomidae (non-biting midges)Chironomidae (non-biting midges)• Chitinous head capsules preserve Chitinous head capsules preserve

in sedimentsin sediments• Abundant in lakesAbundant in lakes• Rapid response timesRapid response times• Sensitive to oxygen changesSensitive to oxygen changes

Photos: J.P. Smol & J. Sweetman

Used to infer past deepwater OUsed to infer past deepwater O22 levelslevels

Relative Abundance (%)

De

pth

in c

ore

(cm

)

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

0

Heter

otris

socla

dius s

p

0 20

Micr

opse

ctra

sp

0 20

Penta

neur

ini

0

Polype

dium

sp

0 20 40

Procla

dius s

p

0

Psectr

oclad

ius sp

0

Cricot

opus

/Orth

oclad

ius sp

0

Coryn

oneu

ra/T

hiene

man

niella

sp

0 20

Tanyta

rsus

sp

0

Dicrot

endip

es sp

0 20

Stem

pellin

a sp

0

Brillia

sp

0

Zalutsc

hia sp

0

Crypt

ochir

onom

us sp

0 20

Tanyta

rsini

Trib

e

0

Orthoc

ladina

e

0

Uniden

tifiab

le

0 20

% L

OI

0

% C

O 3

Profundal Littoral Other

2000

1950

1900

1850

210 Pb

Ogden Lake, Yarmouth Co.Ogden Lake, Yarmouth Co.

Relative Abundance (%)

De

pth

in c

ore

(cm

)

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

32

34

0

Parak

ieffe

riella

sp

0 20

Heter

otris

socla

dius s

p

0

Micr

opse

ctra

sp

0

Serge

ntia

sp

0

Penta

neur

ini

0

Tanyp

odina

e Trib

e

0

Polype

dium

sp

0

Procla

dius s

p

0

Chiron

omus

pall

idivit

atus

0

Psectr

oclad

ius sp

0

Cricot

opus

/Orth

oclad

ius sp

0 20

Coryn

oneu

ra co

rona

ta

0

Tanyta

rsus

sp

0

Dicrot

endip

es sp

0

Mirc

rote

ndipe

s sp

0

Eukief

ferie

lla sp

0

Cladot

anyta

rsus

sp

0

Tribelo

s sp

0

Heter

otan

ytars

us sp

0

Synor

thoc

ladius

sp

0

Tanyta

rsini

Trib

e

0

Chiron

omini

sp

0

Orthoc

ladina

e

0

Uniden

tifiab

le

0 20 40

% L

OI

0

% C

O 3

Profundal Littoral Other

2000

1950

1900

1850

210 Pb

Millet Lake, Lunenburg Co.Millet Lake, Lunenburg Co.

Relative Abundance (%)

De

pth

in c

ore

(cm

)

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

0

Prota

nypu

s sp

0

Heter

otris

socla

dius s

p

0

Micr

opse

ctra

sp

0

Serge

ntia

sp

0 20

Penta

neur

ini

0

Tanyp

odina

e Trib

e

0

Polype

dium

sp

0 20

Procla

dius s

p

0

Chiron

omus

sp

0

Psectr

oclad

ius sp

0

Cricot

opus

/Orth

oclad

ius sp

0

Coryn

oneu

ra co

rona

ta

0 20

Tanyta

rsus

sp

0

Dicrot

endip

es sp

0

Micr

oten

dipes

sp

0

Stem

pellin

a sp

0

Eukief

ferie

lla sp

0

Mes

ocric

opto

pus s

p

0

Heter

otan

ytars

us sp

0

Synor

thoc

ladius

sp

0

Tanyta

rsini

Trib

e

0

Chiron

omini

sp

0

Orthoc

ladina

e

0

Uniden

tifiab

le

0 20 40

% L

OI

0

% C

O 3

Profundal Littoral Other

2000

1950

1900

1850

210 Pb

Scraggy Lake, NSScraggy Lake, NS

Brook Trout Lakes: ConclusionsBrook Trout Lakes: Conclusions

• None of the paleolimnological data suggest directed None of the paleolimnological data suggest directed anoxia trendsanoxia trends

• Measured changes are believed to be the result of inter-Measured changes are believed to be the result of inter-annual variabilityannual variability

• Intervention not required, but watch lakes carefully!Intervention not required, but watch lakes carefully!

• Diatom-inferred changes (work in progress)Diatom-inferred changes (work in progress)

Atlantic Whitefish (Atlantic Whitefish (Coregonus Coregonus huntsmanihuntsmani ) )

• One of few species endemic to One of few species endemic to CanadaCanada

• Only species endemic to Nova Only species endemic to Nova ScotiaScotia

• Formerly anadromousFormerly anadromous

• Only uniquely Canadian fish Only uniquely Canadian fish species ever featured on a postage species ever featured on a postage stampstamp

• Status: critically endangeredStatus: critically endangered

Photo: Canada Post

Atlantic WhitefishAtlantic Whitefish

• Known population is landlocked and restricted to Known population is landlocked and restricted to three Bridgewater area lakes on Petite Riviere three Bridgewater area lakes on Petite Riviere Watershed (Hebb Mill, Milipsiagte, and Minamkeak).Watershed (Hebb Mill, Milipsiagte, and Minamkeak).

• Yarmouth (Tusket River) population extirpated before Yarmouth (Tusket River) population extirpated before 1950’s.1950’s.

0.0-0.5

4.0-4.5

8.0-8.5

12.0-12.5

16.0-16.5

20.0-20.5

24.0-24.5

28.0-28.5

32.0-32.5

36.0-36.5

40.0-40.5

44.0-44.5

48.0-48.5

52.0-52.5

54.0-54.5

0 20

Cyclot

ella

stellig

era

0 20

Fragil

arifo

rma

exigu

a

0 20

Tabell

aria

flocc

ulosa

var lin

earis

0 20

Asterio

nella

ralfs

ii var

amer

icana

> 45u

m

0

Aulaco

seira

ambig

ua

0 20

Tabell

aria

flocc

ulosa

strain

III

0

Aulaco

seira

perg

labra

0

Aulaco

seira

lirat

a

0

Aulaco

seira

perg

labra

var flo

rinae

0 20

Aulaco

seira

dista

ns

5.0 5.3 5.6 5.9 6.2 6.5

Diatom

-infe

rred

pH

0.1 1 2

Diatom

-infe

rred

Gran-

alkali

nity

10 40 50

% O

rgan

ics

10 20 30 40 50

% C

arbo

nate

s

-2.0 -1.0 0.0 1.0 2.0 3.0

PCA Axis

1 S

ite S

core

s

Core Depth(cm)

210Pb Date

2003

1986

1954

1919

1865

Relative Abundance (%) mg/L

20 30

0.0-0.5

4.0-4.5

8.0-8.5

12.0-12.5

16.0-16.5

20.0-20.5

24.0-24.5

28.0-28.5

32.0-32.5

36.0-36.5

40.0-40.5

44.0-44.5

48.0-48.5

52.0-52.5

54.0-54.5

0 20

Cyclot

ella

stellig

era

0 20

Fragil

arifo

rma

exigu

a

0 20

Tabell

aria

flocc

ulosa

var lin

earis

0 20

Asterio

nella

ralfs

ii var

amer

icana

> 45u

m

0

Aulaco

seira

ambig

ua

0 20

Tabell

aria

flocc

ulosa

strain

III

0

Aulaco

seira

perg

labra

0

Aulaco

seira

lirat

a

0.0-0.5

4.0-4.5

8.0-8.5

12.0-12.5

16.0-16.5

20.0-20.5

24.0-24.5

28.0-28.5

32.0-32.5

36.0-36.5

40.0-40.5

44.0-44.5

48.0-48.5

52.0-52.5

54.0-54.5

0 20

Cyclot

ella

stellig

era

0 20

Fragil

arifo

rma

exigu

a

0 20

Tabell

aria

flocc

ulosa

var lin

earis

0 20

Asterio

nella

ralfs

ii var

amer

icana

> 45u

m

0

Aulaco

seira

ambig

ua

0 20

Tabell

aria

flocc

ulosa

strain

III

0

Aulaco

seira

perg

labra

0

Aulaco

seira

lirat

a

0

Aulaco

seira

perg

labra

var flo

rinae

0 20

Aulaco

seira

dista

ns

5.0 5.3 5.6 5.9 6.2 6.5

Diatom

-infe

rred

pH

0.1 1 2

Diatom

-infe

rred

Gran-

alkali

nity

10 40 50

% O

rgan

ics

10 20 30 40 50

% C

arbo

nate

s

0

Aulaco

seira

perg

labra

var flo

rinae

0 20

Aulaco

seira

dista

ns

5.0 5.3 5.6 5.9 6.2 6.5

Diatom

-infe

rred

pH

0.1 1 2

Diatom

-infe

rred

Gran-

alkali

nity

10 40 50

% O

rgan

ics

10 20 30 40 50

% C

arbo

nate

s

-2.0 -1.0 0.0 1.0 2.0 3.0

PCA Axis

1 S

ite S

core

s

Core Depth(cm)

210Pb Date

2003

1986

1954

1919

1865

Relative Abundance (%) mg/L

20 30

Atlantic WhitefishAtlantic Whitefish

Decrease in Decrease in AulacoseiraAulacoseira

Increase in Increase in CyclotellaCyclotella

• No change in diatom-inferred pH (not acid rain)No change in diatom-inferred pH (not acid rain)

• No change in nutrient status (no eutrophication)No change in nutrient status (no eutrophication)

Atlantic WhitefishAtlantic Whitefish

Atlantic Whitefish: ConclusionsAtlantic Whitefish: Conclusions

• Timing of diatom changes (~1890 – 1900’s) does match Timing of diatom changes (~1890 – 1900’s) does match with climatic warming (matches temperature records from with climatic warming (matches temperature records from Halifax (1870 - 2002).Halifax (1870 - 2002).

• Diatom species changes related to change in lake Diatom species changes related to change in lake stratification:stratification: Heavy diatoms (Heavy diatoms (AulacoseiraAulacoseira) need water which is well ) need water which is well

mixed in order to remain afloatmixed in order to remain afloat Lighter diatoms (Lighter diatoms (CyclotellaCyclotella) live in stratified (unmixed) ) live in stratified (unmixed)

water.water.

• Same changes have been recorded in lakes from New Same changes have been recorded in lakes from New Brunswick, Prairies, Northwest Territories, Sweden, and Brunswick, Prairies, Northwest Territories, Sweden, and Finland.Finland.

Other Projects:Other Projects:

• King’s County lakes:King’s County lakes: agricultural production area agricultural production area

of NSof NS rural, some cottages on rural, some cottages on

lakeslakes

• Has increased shoreline Has increased shoreline developments in King’s County developments in King’s County (NS) resulted in a decrease in (NS) resulted in a decrease in water quality?water quality?

Other Projects:Other Projects:

Cape Breton Highlands N.P.Cape Breton Highlands N.P.• Project 1: French LakeProject 1: French Lake

What effects have road What effects have road construction had on French construction had on French Lake? Lake?

- Increased run-off?- Increased run-off?

- Road salt inputs?- Road salt inputs?

• Project 2: Freshwater LakeProject 2: Freshwater Lake What effects have park What effects have park

development had on Freshwater development had on Freshwater Lake?Lake?

Other Projects:Other Projects:

• King’s County lakes:King’s County lakes: agricultural production area agricultural production area

of NSof NS rural, some cottages on rural, some cottages on

lakeslakes

• Has increased shoreline Has increased shoreline developments in King’s County developments in King’s County (NS) resulted in a decrease in (NS) resulted in a decrease in water quality?water quality?

Other Projects:Other Projects:

• Has Halifax Region subdivision Has Halifax Region subdivision development resulted in a change in development resulted in a change in water quality?water quality?

• Two Projects:Two Projects:

Top-bottom analysis (51 lakes)Top-bottom analysis (51 lakes) Present-day vs Pre-impactPresent-day vs Pre-impact

Detailed Analysis (6 lakes) Detailed Analysis (6 lakes) 5 located in subdivisions5 located in subdivisions 1 = Halifax water supply1 = Halifax water supply

Environmental Change in Halifax Environmental Change in Halifax LakesLakes

0.0-0.51.0-1.52.0-2.53.0-3.54.0-4.55.0-5.56.0-6.57.0-7.58.0-8.59.0-9.5

10-10.511-11.512-12.513-13.514-14.515-15.516-16.517-17.518-18.519-19.520-20.521-21.522-22.523-23.524-24.525-25.526-26.527-27.528-28.529-29.5

Dep

th (

cm)

0 20 40 0 20 40 0 20 0 0 0 20 40 0 20 0 20 0 0 0 20 0 5.0 6.0 7.0 8.0 9.00.0 2.0 4.0 6.0 8.0 12 16 20 24 28 32 0.7 0.8 0.9 1.0 1.1

Russell Lake (Dartmouth):Russell Lake (Dartmouth):

Eutrophication from agricultural practicesEutrophication from agricultural practices

0.0-0.250.25-0.51.0-1.252.0-2.253.0-3.254.0-4.255.0-5.256.0-6.257.0-7.258.0-8.259.0-9.25

10.0-10.2511.0-11.2512.0-12.2513.0-13.2514.0-14.2515.0-15.2516.0-16.2517.0-17.2518.0-18.2519.0-19.2520.0-20.2521.0-21.2522.0-22.2523.0-23.2524.0-24.2525.0-25.2526.0-26.2527.0-27.2528.0-28.2529.0-29.2530.0-30.25

0 20 0 20 0 0 20 40 0 20 40 0 20 0 20 40 0 0 0 20 0 20 0 20 40 4.0 5.0 6.0 7.00.0 2.0 4.0 6.0 8.00.0 2.0 4.0 6.0 8.0 10.0-1.3 -1.1 -0.9 -0.7 -0.5

Environmental Change in Halifax Environmental Change in Halifax LakesLakes

Pockwock Lake (Halifax water supply):Pockwock Lake (Halifax water supply):

Impacts of acidification (change in pH and Impacts of acidification (change in pH and colour!)colour!)

SummarySummary

• TEAM = 5-year project to study NS / NB water qualityTEAM = 5-year project to study NS / NB water quality

• Themes: Acidification & EutrophicationThemes: Acidification & Eutrophication Combine paleolimnology and biogeochemical modelingCombine paleolimnology and biogeochemical modeling

• Projects:Projects: Surface-water acidificationSurface-water acidification NS Brook Trout LakesNS Brook Trout Lakes Kings’s Co. development impactsKings’s Co. development impacts Cape Breton Park developmentCape Breton Park development Suburban development in Metro Halifax Suburban development in Metro Halifax

Acidification Paleo-Model Acidification Paleo-Model ComparisonComparison

4.0 5.0 6.0 7.0

4.0

5.0

6.0

7.0

MAGIC model inferred pH

Dia

tom

-infe

rred

pH

Allens

Bird

Brenton

JesseTedford

Trefry

Beaverskin

Big Dam East

Pebbleloggitch

Annis

Huey

Little Wiles

Matthew

Halfway Brook

Branch GlasgowJohn Dee

Long

Mica HillRound

4.0 5.0 6.0 7.0

4.0

5.0

6.0

7.0

MAGIC model inferred pH

Dia

tom

-infe

rred

pH

Allens

Bird

Brenton

JesseTedford

Trefry

Beaverskin

Big Dam East

Pebbleloggitch

Annis

Huey

Little Wiles

Matthew

Halfway Brook

Branch GlasgowJohn Dee

Long

Mica HillRound

Acidification Paleo-Model Acidification Paleo-Model ComparisonComparison

-1.0 0.0 1.0 2.0

-1.0

0.0

1.0

2.0

MAGIC Inferred pH change

Dia

tom

-inf

erre

d pH

ch

an

ge

Allens

Bird

Brenton

Jesse

Tedford

TrefryAnnis

Huey

Little Wiles

Matthew

Beaverskin

Big Dam East

Pebbleloggitch

Halfway Brook

Branch

Glasgow

John Dee

Long

Mica Hill

Round

-1.0 0.0 1.0 2.0

-1.0

0.0

1.0

2.0

MAGIC Inferred pH change

Dia

tom

-inf

erre

d pH

ch

an

ge

Allens

Bird

Brenton

Jesse

Tedford

TrefryAnnis

Huey

Little Wiles

Matthew

Beaverskin

Big Dam East

Pebbleloggitch

Halfway Brook

Branch

Glasgow

John Dee

Long

Mica Hill

Round