The threat of Calcium (Ca) decline for the

life in Muskoka (& Haliburton) lakes by Norman Yan, York University

My objectives

1. Briefly review evidence for and causes of environmental Calcium (Ca) decline, with its link to acidification and logging

2. Determine if Ca has fallen enough to damage aquatic life, using my “little living lawnmowers” (animal plankton) as miner’s canaries

3. Consider the long-term implications of Ca decline and what we can do about it.

Calcium (Ca) decline in 7 of 8 Dorset lakes*

1975 1980 1985 1990 1995 2000 2005

1.5

2.0

2.5

3.0

3.5

Ice-F

ree C

a (

mg•L

-1)

BC CB CN DE

HP HY PC RCM

*Molot and Dillon 2008, Yan et al. 2008, (Dorset Special Issue of CJFAS, May 2008)

Dickie (DE)

Is different

Why are calcium levels rising in Dickie Lake?

Ca load from all un-guaged sources – 2700 kg/yr

Dust suppressant added yearly >1998 – 10,450 L

Ca concentration in suppressant solution – 196 g/L

Ca added in dust suppressant since 1998 – 2050 kg/yr

Ca decline in 37 Muskoka/Haliburton lakes*

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5C

a (

mg

/L)

in 2

00

4_

05

Ca (mg/L) in the 1980's

1:1

Change over time = 12%

*Michelle Palmer’s PhD vs. old DESC data

Median change = -12%

Muskoka’s Recreational Water Quality Monitoring Program

Is Ca changing across the District?

Calcium (<5 mg/l)

First Value – 2004-6

Last Value – 2007-9

r = 0.926

Intercept = 0 (Yes)

Slope = 1 (No <1)

0

1

2

3

4

5

6

0 1 2 3 4 5 6

First Value

Last

Valu

e

Ca has fallen between the two time periods in 90% of the low Ca lakes

Data Providers

Keller (MOE)

Paterson (MOE)

Palmer (York)

Jeffries (EC)

Turner (ELA)

Weeber &

McNicoll (CWS)

Jeziorski et al. (2008)

Science 322: 1374

Ca mg.L-1

>3.0

2.5-3.0

2.0-2.5

1.5-2.0

<1.5

Why is lake water calcium (Ca) falling?

Acid rain and logging/afforestation are depleting soil Ca

Soil Ca

Soil Ca

Soil Ca

Biomass

Biomass

Ca

Ca

Ca

A-

Caw

Caw

Caw

A-

A-

Cad Cad

H,Cad

H, Al

H

w = weathering

d = deposition

A- = anions

Biomass – tree mass

Al - aluminum Thanks to Shaun Watmough, Trent U

SO2 emissions have been reduced by 55% from 1980

levels in Canada, and by 40% in the USA

1960 1970 1980 1990 2000 2010

0

500

1000

1500

2000

2500

3000

SO

2 e

mis

sio

ns (

10

3 t•y

r-1)

Em

issi

ons

from

Sudbury

sm

elte

rs

Year

And rainfall acidity has declined, but it is still acid *

1980-1984 2000-2004

*US EPA and Env. Canada

Hence, soils in 21 forests in eastern North

America and Europe are still losing Ca*

-40

-30

-20

-10

0

EL

A-N

W

EL

A-E

Mu

sk/H

al-

PC

Mu

sk/H

al-

HP

La

c C

lair

Be

ar

Bro

ok

Co

ne

Po

nd

Hu

bb

ard

Vil

lin

gen

Le

hste

nb

ac

h

Bir

ke

nn

es

An

nu

al

Ca

exp

ort

(k

g h

a-1

)

* Watmough et al. 2005 Env. Monitor Assess. 109: 1-36

0

20

40

60

80

100

120

PC1

CB1

RC4

HP3A

HP4

HP6

HP6A

% D

istr

ibu

tio

n

Soil

Forest

*from Watmough & Dillon 2003 Forest Ecol. Manag. 177:155-177

Logging + forest re-growth also matter

because there is so much Ca in the trees

Can Ca decline damage aquatic life, eg.

Cause extinctions of animal plankton species?

Animal plankton vary in size

Bosmina

0.3 mm

Bythotrephes

Spiny water flea

15 mm Keratella

0.05 mm

They vary in food web position

Polyphemus

A predator

Daphnia

A herbivore

And. they also vary in Ca needs

Bythotrephes

0.03% Ca

(Kim & Yan in prep)

Holopedium

0.3% Ca

Daphnia

5% Ca

(Jeziorski & Yan, 2006)

Species

Calc

ium

conte

nt (%

dry

weig

ht)

0.0

2.0

4.0

6.0

8.0

10.0

Bosmina

L. minutus

M. edax

H. gibberum

D. ambigua

D. catawba

D. mendotae

D. pulex

A A A A B C C C

Ca needs differ among species

Adam Jeziorski

Jeziorski & Yan (2006)

The “little

living

lawnmower”

Daphnia*

It’s ~3% Ca

* Photo by D. Taylor, U of Buffalo

Muskoka, formally called..

The 2006 Muskoka lake survey crews from York U

Erika

Allegra

Modelled Observed Pattern of occurrence

Of 5 Daphnia species

with Ca in 311 lakes (Cairns & Yan under review)

The occurrence of species

falls at Ca levels <2 mg/L

Might they have disappeared

From these lakes?

Allegra Cairns

A primer in Daphnia “paleolimnology”

Abdomen with claw

Teeth sets on abdominal claw

Sketch of a Daphnia

3 sets

of teeth

Primer in paleolimnology 2*

Preparing to

Take a core

Retrieving

The core

Sectioning

The core

*from John Smol website, Queen’s U

Loss of Daphnia from Plastic Lake core*

Year

1800 1850 1900 1950 2000

% D

ap

hn

ia p

ule

x

0

5

10

15

20

25

30

pH

5.0

5.2

5.4

5.6

5.8

6.0

Ca (m

g·L

-1)

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

pH

Ca

% Daphnia pulex

1980 1990 2000

% D

ap

hn

ia p

ule

x c

om

ple

x

0

5

10

15

20

pH

5.0

5.2

5.4

5.6

5.8

6.0

Ca (m

g·L

-1)

1.2

1.4

1.6

1.8

2.0

2.2

2.4

*Jeziorski et al. (2008)

And they are lost whenever Ca < 2 mg/L*

Measured Ca (mg·L-1) 1980s

0 1 2 3 4

Mea

su

red C

a (

mg·L

-1)

- 20

04/0

5

0

1

2

3

4A B

1:1

Measured Ca (mg·L-1

) - 2000s

< 1.5

1.5 - 2.0

2.0 - 2.5

2.5-3.0> 3.0

% c

ha

ng

e in

Dap

hn

ia s

pp

. se

dim

enta

ry m

icro

fossil

ab

un

da

nce

-60

-40

-20

0

20

40

60

B n = 43P = 0.023H =11.371

5 12 13 6 7

*Michelle Palmer & Anna DeSellas’ work in Jeziorski et al. (2008)

Correlation vs. Causation?

• There are both spatial and temporal patterns

suggesting loss of Ca-rich life (i.e. ecological

damage) associated with low Ca, i.e Ca ~1.5 to

2 mg/L, but

• has low Ca actually caused the damage?

The FLAMES lab at Dorset

0 1 2 3 4 5 6

0.6

0.8

1.0

1.2

1.4

1.6

Insta

r IV

bo

dy le

ng

th (

mm

)

[Ca] mg/L

D. pulex growth at instar IV with Chaoborus kairomone

Ca <2 mg/L reduces Daphnia growth in the lab*

*Riessen, Linley, Altshuler and Yan (under review)

And low individual growth reduces population growth

At Ca levels <1.5 mg/L

Ashforth & Yan (2008)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.1 0.5 1 1.5 2 5 10

Ca (mg/L)

r

(ne

on

ate

s/f

em

ale

•da

y)

20

24

28

Popula

tion g

row

th r

ate

(/

d)

2 day replacement bioassay

• Lakes with 4 [Ca]s - 1.1, 1.3, 1.4, 2.4 mg/L

• 17 day endpoint (July-Aug ‘08)

• Transfer to new tubes in field

• Open treatments with or without added

food

• Closed treatment with added Ca and

Ca+food

Animals examined in lab

• # of neonates

• # of shed carapaces

• Verify survival

But can Ca decline cause such

losses in lakes, not just in the lab? Allegra Lily

Lowest Ca Low Ca Mid Ca Reference

Treatment Screen

size 1.1 mg/L 1.3 mg/L 1.4 mg/L 2.3 mg/L

Raw 53um

Survival of young Daphnia over 17 days

in the open tubes (Cairns & Yan in prep.)

Lower Schufelt, Ca = 1.06

& Lynch, Ca = 1.3 mg/L

Buck Lake

Ca = 2.3 mg/L

CAISN 58 Lake

Ca = 1.4 mg/L

Fre

quency D

istr

ibution o

f la

ke C

a c

oncentr

ations

2488 lakes *

*from D. Jeffries Env. Can.

We have a lot of lakes with Ca levels this low in Canada (n=2488)*

In summary

• Most Canadian Shield lakes have low Ca levels, and levels have been falling of late

• The decreases are linked to our thin, mineral-poor soils, decades of acid rain, a few logging cycles, and paradoxically, recent reductions in acid input.

• Levels below 1 mg/L may soon be common.

• The few Ca-rich aquatic species we have studied are in trouble at <1.5-2 mg/L of Ca, and we have a lot of such lakes

• Calcium decline is also an emerging threat to our forests (Watmough at Trent U)

• So far we have seen impacts on water fleas, and likely on crayfish, but other Ca-rich life is also at risk

And do we see damage in our long-term study lakes?

1975 1980 1985 1990 1995 2000 2005

1.5

2.0

2.5

3.0

3.5

Ice-F

ree C

a (

mg•L

-1)

BC CB CN DE

HP HY PC RCM

*Molot and Dillon 2008, Yan et al. 2008, (Dorset Special Issue of CJFAS, May 2008)

Plastic (PC)

Is extreme

Are we losing Ca-rich species in Plastic Lake?

*Yan, Ingram, Keller, Witty, unpubl. data

1980 1985 1990 1995 2000 2005 2010

0

1

2

3a

bu

nd

an

ce

of 5

hig

h-C

a d

ap

hn

iids (

log

x+

1)

Year

Plastic: long-term loss of 5 Ca-rich daphniids

log Abun = 146-0.073*year

r = -0.64, n = 30, p<0.001

1975 1980 1985 1990 1995 2000 2005 2010

2

4

6

8

10C

a,

TP

& p

H (

SD

)

Ca

pH

TP

Plastic Lake

Paterson et al. unpubl. MOE data

1975 1980 1985 1990 1995 2000 2005 2010

1.2

1.4

1.6

1.8

2.0

2.2C

a (

mg/L

± 1

SD

)

X Axis Title

Plastic Lake Ca trend

MOE data Year

Summary

• We have increasingly strong evidence that Ca <1.5

mg/L is harmful to Ca-rich animal plankton

• A large % of eastern Canadian lakes are approaching

or have dropped below this threshold

• The paleo-ecological Cladoceran record suggests Ca

levels were not this low prior to acid rain.

• The potential counteracting effects of rising pH and

falling Ca warrant research

• Damaging Ca thresholds may be higher than 1.5

mg/L for other Ca-rich taxa

• Can anything be done?

People have a huge effect on Ca dynamics

What can be done

• Quickly increase our knowledge about the extent and effects of Ca decline in Canada – Norm’s MOE/York agreement

– Additional research via the Muskoka watershed node of the Canadian Water Network

• Use the current and developing knowledge to help develop strategies to deal with the problem, eg. – further reductions in S and N emissions

– Changes in forest management practices, including logging frequency alterations, bark, twigs, etc.

– Ca supplementation (wood ash, dust suppressants)

– Become gardeners of the forest

• Communicate the issue broadly

Acknowledgements

to Paul for the invitation

Staff, funding & data from the OMOE’s Dorset Environmental

Science Centre, and the MOE’s Best in Science Program

The Biology & other departments at York University

Canadian Aquatic Invading Species Network

Canadian Wildlife Service and NWRI

NSERC Strategic and Discovery grant programs

Recent & emerging Ca work in the lab

1. In print or press 1. Ashforth, D. and N.D. Yan 2008 Limnol. Oceanogr. 53: 420-432.

2. Cairns, A. and N.D. Yan 2009 Env. Reviews 17: 67-79.

3. Jeziorski, A. et al. 2008. Science. 322:1374-1377.

4. Jeziorski, A and N.D. Yan 2006 Can. J. Fish. Aquat. Sci. 63: 1007-1013.

5. Yan, N.D. 2008 Can. J. Fish. Aquat. Sci. 65: 862-877.

6. Yao, H. et al. 2011 Water Res. Res. (in press)

2. Under review 1. Cairns, A, A. Jeziorski and N. Yan. Both Ca decline and polymixis reduce

daphniid prevalence. CJFAS (under review).

2. Cairns and Yan. A field experiment of the threat of Ca decline to daphniids…. Limnol. Oceangr. (under review)

3. Riessen et al. Calcium, kairomones and growth of Daphnia. Limnol. Oceanogr (under review this month)