LONG-TERM DYNAMICS AND CLIMATE IMPACTS

ON LAKES IN AUSTRIA, CENTRAL EUROPE:

A REVIEW

Martin T. DokulilInstitute for Limnology

Austrian Academy of Sciences

Mondsee, Austria

Content

• Lakes in Austria - A brief outline

• Eutrophication and oligotrophication history

• Restoration measures

• Case study Mondsee

• Climate impacts on lakes in Austria and Central Europe

• Case study Neusiedler See

• What can be learned from a small temperate country?

Lake districts in Austria

Mondsee

Attersee Traunsee

Wolfgangsee

water shed

Salzkammergut

region

Hallstätter See

Lake Ir Mo At Ha Wo TrAltitude [m] 533 481 469.2 508 538 422A [km²] 3.5 14.2 45.9 8.6 12.8 25.6V [Mio m³ 53 510 3945 557 667.1 2302z [m] 15.3 36 84.2 64.9 52 89.7zmax [m] 32 68.3 170.6 125.2 113.1 191r [y] 1.7 1.7 7 0.5 3.9 1A' [km²] 27.5 247 463.5 646.5 124.8 1417

Irrsee(Ir)

Mondsee(Mo)

Attersee(At)

Traunsee(Tr)

Hallstättersee(Ha)

Wolfgangsee(Wo)

Jepp

esen

et a

l. Fr

eshw

ater

Biol

ogy

(200

5)Effects of oligotrophication

Tota

l pho

spho

rus,

TP

[µg

L-1]

0

20

40

60

80 Grabensee TP Mattsee TP Obertrumer See TP

0

10

20

30

40Fuschlsee TP Wallersee TP Wolfgang See TP Zellersee TP

1980 1985 1990 1995 2000 2005

Tota

l Bio

volu

me,

B [m

m3

L-1]

0

2

4

6

Grabensee B Mattsee B Obertrumer See B

1980 1985 1990 1995 2000 20050

1

2

3

Fuschlsee B Wallersee B Wolfgang See B Zellersee B

r2 = 0.92

r2 = 0.94

r2 = 0.89

r2 = 0.62

r2 = 0.61

r2 = 0.72

r2 = 0.71

r2 = 0.64

Lake dynamicsL

akes

in th

eco

unty

Salz

burg

Total phosphorus [µg.l-1]

1 10

Chl

orop

hyll-

a [µ

g.l-1

]

1

10

AtterseeHallstätterseeTraunseeMondseeWolfgangsee

1 : 1

Oligotroph

Mesotroph

Ultra-Oligotroph

TP / Chl-a diagramL

akes

in th

eSa

lzka

mm

ergu

t reg

ion

Case

study

Mondsee

1970 1980 1990 2000

Dep

th (m

)

0

2

4

6

8

10

12

14I II III IVI

Secchi

depth

Mondsee 1957-2002D

okul

il &

Teu

bner

, Fre

shw

at. B

iol.

(200

5)

Phosphorus

Mondsee 1957-2002D

okul

il &

Teu

bner

, Fre

shw

at. B

iol.

(200

5)

1970 1980 1990 2000

Tota

l pho

spho

rus

(µg

L-1)

0

10

20

30

40

50

Avg-TPDI-TP

PI-TP

PI+DI-TP

I II III IV

Biovolume Mondsee 1957-2002D

okul

il &

Teu

bner

, Fre

shw

at. B

iol.

(200

5)

1960 1970 1980 1990 2000

Bio

volu

me

(mm

3 L-1

)

0

2

4

6

8

10

12

14

Annual average biovolum

e (mm

3 L-1)

0

1

2

3

4II III IVI

cohe

renc

e

Total phosphorus [TP, µg.l-1]

7 8 9 10 11 12 13

Chl

orop

hyll-

a [C

hl-a

, µg.

l-1]

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

1982

1983

1984 1985

1986

1987

1988 19891990

1991

1992

19931994

1995

1996Mondsee

Cyano

ChloroChryso

CryptoDino

Bacill

1997

19981999

2000

2001

TP / Chl-a developmentD

okul

il &

Teu

bner

, H

ydro

biol

ogia

(200

3)

EvidenceO

ligot

roph

icat

ion

1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002

Tota

l Phy

topl

ankt

on-B

iom

ass

[mg

m-3

]

0

1000

2000

3000

4000

0.1

1

10

100

1000

10000 Cyanobacteria Bacillariophyta

80 90 00

Bio

volu

me

[106 µ

m3 L

-1]

0.1

1

10

100

1000

10000Cryptophyta

Dinophyta

Year80 90 00

Chrysophyta

80 90 00

Chlorophyta

Long term trends phytoplankton groupsM

onds

ee

Month

1 3 5 7 9 11

Chrysophytes

1 3 5 7 9 11

Bio

volu

me

[106

µm3

L-1]

0.1

1

10

100

1000

10000Cryptophytes

0.1

1

10

100

1000

10000Cyanobacteria Bacillariophytes Dinophytes

1 3 5 7 9 11

Chlorophytes

Seasonal trends of phytoplankton groupsM

onds

ee

Algal groups1960 1970 1980 1990 2000

0

500

1000

1500

2000

0

500

1000

1500

2000

Ann

ual a

vera

ge b

iovo

lum

e of

phy

topl

ankt

on g

roup

s(m

m3

L-1)

0

500

1000

1500

2000

Years1960 1970 1980 1990 2000

0

500

1000

1500

2000

0

500

1000

1500

2000

Cyanobacteria

Bacillariophyceae

Dinoflagellates

Chrysophyceae

Cryptophyceae

DominantSub-dominant

Dok

ulil

& T

eubn

er,

Hyd

robi

olog

ia(2

003)

Biovolume / SRSiO

ligot

roph

icat

ion

Biovolume (mm3 L-1)

0.0 0.5 1.0 1.5 2.0 2.5

SRSi

(mg

L-1 )

0.2

0.4

0.6

0.8

1.0

1.2

1.4r ² = 0.456

1982

2001

oligotroph o-m mesotroph eutroph

cohe

renc

eDiatoms

Bacillariophyceen gesamt

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

Bio

volu

me

[106 µ

m3

L-1]

0

1000

2000

cohe

renc

eDiatom species

Cyclotella radiosa

100

200

Asterionella formosa

100

200

600

800

Tabellaria flocculosa var. fenestrata

1000

2000

3000

4000

Fragilaria crotonensis

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

0

100

200

300

Bio

volu

me

[106 µ

m3

L-1]

cohe

renc

eConceptual summary

Dok

ulil

& T

eubn

er,

Fre

shw

at. B

iol.

(200

5)

NAOWinter

vs. Air & LSTC

oeff

icie

nt o

f det

erm

inat

ion

(r²%

) FromLivingstone & Dokulil (2001) L & O 46, 1220-1227

NAOWinter

vs. LSTC

oeff

icie

nt o

f det

erm

inat

ion

(r²%

)

0

10

20

30

40

50

J F M A M J J A S O N D

Mattsee

0

10

20

30

40

50

J F M A M J J A S O N D

Wallersee

0

10

20

30

40

50

J F M A M J J A S O N D

Holzöstersee

0

10

20

30

40

50

J F M A M J J A S O N D

Neusiedlersee

0

10

20

30

40

50

J F M A M J J A S O N D

Grundlsee

0

10

20

30

40

50

J F M A M J J A S O N D

Irrsee

0

10

20

30

40

50

J F M A M J J A S O N D

Altausseer See

P<0.05

Millstättersee

0

10

20

30

40

50

J F M A M J J A S O N D0

10

20

30

40

50

J F M A M J J A S O N D

Ossiachersee

Deep water temperatures (DWT)C

entr

al E

urop

e

DWT vs. NAOC

entr

al E

urop

e

Case

study

Neusiedlersee

Bio

mas

s [m

g m

-3]

0

500

1000

1500

2000

2500

3000

Cyanobacteria CryptophytesChrysophytes BacillariophytesDinophytesEuglenophytes Chlorophytes

1970 1975 1980 1985 1990 1995 2000

Chl

orop

hyll-

a [m

g m

-3]

0

5

10

15

Tota

l Pho

spho

rus

[TP,

mg

m-3

]

0

20

40

60

80

100

120

140

160

180

Neu

sied

ler

See

Phytoplankton

dynamic

1968-2004

0 20 40 60 80 100 120 140 160 1800

2

4

6

8

10

12

14

16

18

20

Chl

orop

hyll-

a [C

hl-a

, mg

m-3

]

Total phosphorus [TP, mgm-3]

Neusiedler See

19701975

1977

1978

19791980

1990

1996

1982

1983

1984

1985

1987

1988

1989

1976

Cyano

ChloroChryso

CryptoDino

Bacill

2000

Neu

sied

ler

See

Trophic

diagram

1970-2000

Neu

sied

ler

See

Seasonal

average

total biomass

Spring

Bio

mas

s [m

g m

-3]

0

1000

2000

3000

4000

5000

6000Winter

1970 1980 1990 2000

Bio

mas

s [m

g m

-3]

0

1000

2000

3000

Summer

1970 1980 1990 2000

Autumn

Neu

sied

ler

See

Annual

average

algal

groups

Bio

mas

s [m

g m

-3]

0

200

400

600

800

1000

1200

1400

1970 1980 1990 2000

Bio

mas

s [m

g m

-3]

0

200

400

600

800

1000

1200

1400

1970 1980 1990 2000

Cyano Crypto

Bacillario Chloro

SPRING

Bio

mas

s [m

g m

-3]

0

200

400

600

800

1000

1200

1400

1970 1980 1990 2000

Bio

mas

s [m

g m

-3]

0

500

1000

1500

2000

1970 1980 1990 2000

Cyano Crypto

Bacillario Chloro

AUTUMN

Bio

mas

s [m

g m

-3]

0

200

400

600

800

1000

1200

1970 1980 1990 2000

Bio

mas

s [m

g m

-3]

0

1000

2000

3000

1970 1980 1990 2000

Cyano Crypto

Bacillario Chloro

SUMMER

Bio

mas

s [m

g m

-3]

0

200

400

600

800

1000

1200

1400

1970 1980 1990 2000

Bio

mas

s [m

g m

-3]

0

1000

2000

3000

4000

1970 1980 1990 2000

Cyano Crypto

Bacillario Chloro

WINTER

Total Phosphorus [TP, mg m-3]

0 50 100 150 200

Chl

orop

hyll-

a [m

g m

-3]

0

5

10

15

20

Annual NAO Index

-1.5 -1.0 -0.5 0.0 0.5 1.0 1.5

Res

idua

ls T

P/C

hl-a

-6

-4

-2

0

2

4

6

8

Chl-a = 4.56 + 0.050 TPr² = 0.53, n =31, p < 0.001

Res = 0.11 + 2.64 NAOr² = 0.26, n = 31, p = 0.003

Climate change (NAO)

0

5

10

15

20

25

30

35

40

J F M A M J J A S O N D

Coefficient of determination (r²) between winter MOIDJFM index and monthly mean lake surface temperature in Neusiedler See

Neu

sied

ler

See

Summary

• Austrian lakes underwent anthropogenic eutrophication

• Increase in nutrients, primary productivity, algal biomass toxic

cyanobacteria

• External and internal restoration measures

• Reduction in nutrient loading Oligotrophication

• Reduction in phytoplankton biomass and species composition

• Remediation of lakes retarded process (> 10 years)

• EC Water Framework Directive aims for ‘good ecological status’ of

all European waters by 2015

• New challenge impacts of climate change

Take home messages

• Good legislation, continuously adapted

• Good management of sewage treatment and lake restoration

• Scientific based monitoring strategies

• Strategies must used best available techniques

• Strategies have to be catchment orientated and basin-wide

• Public awareness and participation

• Fulfill EC-requirements such as the Water Framework Directive (WFD)

• Future strategies must forecast and include impacts from climate

change