Paleolimnological assessment of nutrients and algae in the LOW: - - PowerPoint PPT Presentation

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Paleolimnological assessment of nutrients and algae in the LOW: - - PowerPoint PPT Presentation

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Paleolimnological assessment of nutrients and algae in the LOW: Paleolimnological assessment of nutrients and algae in the LOW: Review of initiatives and update on research Paleolimnological assessment of nutrients and algae in the LOW:

slide-1
SLIDE 1

Paleolimnological Paleolimnological assessment of nutrients and algae in the LOW: assessment of nutrients and algae in the LOW:

Review of initiatives and update on research

slide-2
SLIDE 2

Paleolimnological Paleolimnological assessment of nutrients and algae in the LOW: assessment of nutrients and algae in the LOW:

Review of initiatives Review of initiatives

  • Explore possibility of link between recent algal blooms &

Explore possibility of link between recent algal blooms & TP TP

  • Have TP concentrations increased in the last few decades?
slide-3
SLIDE 3

Paleolimnological Paleolimnological assessment of nutrients and algae in the LOW: assessment of nutrients and algae in the LOW:

Review of initiatives Review of initiatives

  • Explore possibility of link between recent algal blooms &

TP

  • Have TP concentrations increased in the last few decades?
  • Survey of modern sedimentary diatom assemblages in LOW (ON)

Survey of modern sedimentary diatom assemblages in LOW (ON)

  • Training set of LOW sites along TP gradient

Training set of LOW sites along TP gradient

  • Identify areas of elevated and low nutrient concentrations

Identify areas of elevated and low nutrient concentrations

  • Do diatoms track within

Do diatoms track within-

  • lake differences in

lake differences in env

  • env. conditions & water quality?

. conditions & water quality?

  • Development of diatom

Development of diatom-

  • based TP model

based TP model

slide-4
SLIDE 4

Paleolimnological Paleolimnological assessment of nutrients and algae in the LOW: assessment of nutrients and algae in the LOW:

Review of initiatives Review of initiatives

  • Explore possibility of link between recent algal blooms &

Explore possibility of link between recent algal blooms & TP TP

  • Have TP concentrations increased in the last few decades?
  • Survey of modern sedimentary diatom assemblages in LOW (ON)

Survey of modern sedimentary diatom assemblages in LOW (ON)

  • Training set of LOW sites along TP gradient

Training set of LOW sites along TP gradient

  • Identify areas of elevated and low nutrient concentrations

Identify areas of elevated and low nutrient concentrations

  • Do diatoms track within

Do diatoms track within-

  • lake differences in

lake differences in env

  • env. conditions & water quality?

. conditions & water quality?

  • Development of diatom

Development of diatom-

  • based TP model

based TP model

  • Full core analyses

Full core analyses – – historical changes in lake water quality historical changes in lake water quality

slide-5
SLIDE 5

Paleolimnological Paleolimnological assessment of nutrients and algae in the LOW: assessment of nutrients and algae in the LOW:

Review of initiatives Review of initiatives

  • Explore possibility of link between recent algal blooms &

Explore possibility of link between recent algal blooms & TP TP

  • Have TP concentrations increased in the last few decades?
  • Survey of modern sedimentary diatom assemblages in LOW (ON)

Survey of modern sedimentary diatom assemblages in LOW (ON)

  • Training set of LOW sites along TP gradient

Training set of LOW sites along TP gradient

  • Identify areas of elevated and low nutrient concentrations

Identify areas of elevated and low nutrient concentrations

  • Do diatoms track within

Do diatoms track within-

  • lake differences in

lake differences in env

  • env. conditions & water quality?

. conditions & water quality?

  • Development of diatom

Development of diatom-

  • based TP model

based TP model

  • Full core analyses

Full core analyses – – historical changes in lake water quality historical changes in lake water quality

  • Comparisons between reference & impact sites
  • reference = lower nutrients & no algal blooms
  • impact = elevated nutrients & algal blooms occur
slide-6
SLIDE 6

Paleolimnological Paleolimnological assessment of nutrients and algae in the LOW: assessment of nutrients and algae in the LOW:

Review of initiatives Review of initiatives

  • Explore possibility of link between recent algal blooms &

Explore possibility of link between recent algal blooms & TP TP

  • Have TP concentrations increased in the last few decades?
  • Survey of modern sedimentary diatom assemblages in LOW (ON)

Survey of modern sedimentary diatom assemblages in LOW (ON)

  • Training set of LOW sites along TP gradient

Training set of LOW sites along TP gradient

  • Identify areas of elevated and low nutrient concentrations

Identify areas of elevated and low nutrient concentrations

  • Do diatoms track within

Do diatoms track within-

  • lake differences in

lake differences in env

  • env. conditions & water quality?

. conditions & water quality?

  • Development of diatom

Development of diatom-

  • based TP model

based TP model

  • Full core analyses

Full core analyses – – historical changes in lake water quality historical changes in lake water quality

  • Comparisons between reference & impact sites
  • reference = lower nutrients & no algal blooms
  • impact = elevated nutrients & algal blooms occur
  • Have nutrient levels changed over the past ca. 200 years?
  • Explore alternative mechanisms for recent changes
slide-7
SLIDE 7

Lake of the Woods training set

Site

P P

  • 1

2 P P

  • 1

3 P P

  • 1

4 P P

  • 6

P P

  • 1

5 P P

  • 5

P P

  • 4

P P

  • 7

P P

  • 3

P P

  • 2

P P

  • 8

P P

  • 1

P P

  • 9

P P

  • 1

1 P P

  • 1

8 P P

  • 1

P P

  • 1

7 P P

  • 1

9 P P

  • 2

P P

  • 1

6

Total phosphorus (μg·L-1)

5 10 15 20 25 30

Whitefish Bay PP-1

Summer measurements

Bigstone Bay

Total Phosphorus Gradient Total Phosphorus Gradient

Results of this initiative published in J. Great Lakes Res. Pla et al. 2005 31:253-266

Update on research Update on research

slide-8
SLIDE 8

+

Lake of the Woods training set

From J Great Lakes Res Pla et al. 2005 31: 253-266

16 sites in LOW 16 sites in LOW 55 Minnesota lakes 55 Minnesota lakes Northern Lakes and Forests (NLF) sites

From J Paleolimnol Ramstack et al. 2003 29: 79-94

DI-TP model development for LOW DI-TP model development for LOW

Update on research Update on research

slide-9
SLIDE 9

Location of sampling sites for sediment cores Location of sampling sites for sediment cores

Impact Site Reference Site

  • 96º
  • 96º
  • 95º
  • 95º
  • 94º
  • 94º
  • 93º
  • 93º

49º 49º 50º 50º

Ontario Manitoba Minnesota

Kenora

km

10

PP PP-

  • 1

1 Bigstone Bay Whitefish Bay

Update on research Update on research

slide-10
SLIDE 10

REFERENCE SITE Whitefish Bay IMPACT SITE PP-1 IMPACT SITE Bigstone Bay

~ 1980 ~ 1970 ~ 1970

Update on research Update on research

Diatom analysis complete Please visit our poster! Please visit our poster!

Rühland et al.: in preparation.

slide-11
SLIDE 11
  • 1.5
  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0

  • 3
  • 2
  • 1

1 2 3

  • ca. 1884
  • ca. 2002

~1982

  • 2.0
  • 1.5
  • 1.0
  • 0.5

0.0 0.5

PCA axis 2

  • 2
  • 1

1 2 3

  • ca. 2006

~1965

PCA axis 1

  • 2.0
  • 1.5
  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0

  • ca. 1800

Whitefish Bay Reference

  • ca. 1800
  • 3
  • 2
  • 1

1 2 3

  • ca. 2005

~1905

PP-1 Impact Bigstone Bay Impact

Trajectories of diatom change over time Trajectories of diatom change over time

Update on research Update on research

Rühland et al.: in preparation.

slide-12
SLIDE 12

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Annual Temperature (ºC)

  • 1

1 2 3 4 5 6 y = 0.0112x + 1.8032

1.19 ºC  since 1899

5-yr running mean

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Winter Temperature (ºC)

  • 22
  • 20
  • 18
  • 16
  • 14
  • 12
  • 10
  • 8
  • 6

y = 0.0216x - 16.136

2.29 ºC  since 1899

5-yr running mean

Kenora Kenora Temperature vs. Diatom trends emperature vs. Diatom trends

Update on research Update on research

  • 96º
  • 95º
  • 94º
  • 93º

49º 50º

Kenora Kenora Minnesota O n t a r i

  • Manitoba

Rühland et al.: in preparation.

slide-13
SLIDE 13

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Annual Temperature (ºC)

  • 1

1 2 3 4 5 6 y = 0.0112x + 1.8032

1.19 ºC  since 1899

5-yr running mean

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Winter Temperature (ºC)

  • 22
  • 20
  • 18
  • 16
  • 14
  • 12
  • 10
  • 8
  • 6

y = 0.0216x - 16.136

2.29 ºC  since 1899

5-yr running mean

Kenora Kenora Temperature vs. Diatom trends emperature vs. Diatom trends

PCA scores (SD units)

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0

Annual Temperature (ºC)

1.5 2.0 2.5 3.0 3.5 4.0

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

PCA sample scores Annual Temperature

1.5 2.0 2.5 3.0 3.5 4.0

  • 2
  • 1

1 2

a b c R=0.67 R=0.84 R=-0.73

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Year AD

Whitefish Bay Reference PP-1 Impact Bigstone Bay Impact

Update on research Update on research

  • 96º
  • 95º
  • 94º
  • 93º

49º 50º

Kenora Kenora Minnesota O n t a r i

  • Manitoba

Rühland et al.: in preparation.

slide-14
SLIDE 14

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Annual Temperature (ºC)

  • 1

1 2 3 4 5 6 y = 0.0112x + 1.8032

1.19 ºC  since 1899

5-yr running mean

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Winter Temperature (ºC)

  • 22
  • 20
  • 18
  • 16
  • 14
  • 12
  • 10
  • 8
  • 6

y = 0.0216x - 16.136

2.29 ºC  since 1899

5-yr running mean

Kenora Kenora Temperature vs. Diatom trends emperature vs. Diatom trends

DI-TP (µg/L)

14 16 18 20 22 24 26 1 2 3 4

DI-TP Annual Temperature

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

14 16 18 20 22 1 2 3 4 8 10 12 14 16 18 20 22 24 1 2 3 4 d

e f R=-0.61 R=-0.46 R=-0.19

Annual Temperature (ºC) PCA scores (SD units)

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0

Annual Temperature (ºC)

1.5 2.0 2.5 3.0 3.5 4.0

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

PCA sample scores Annual Temperature

1.5 2.0 2.5 3.0 3.5 4.0

  • 2
  • 1

1 2

a b c R=0.67 R=0.84 R=-0.73

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Year AD

Whitefish Bay Reference PP-1 Impact Bigstone Bay Impact

Update on research Update on research

  • 96º
  • 95º
  • 94º
  • 93º

49º 50º

Kenora Kenora Minnesota O n t a r i

  • Manitoba

Rühland et al.: in preparation.

slide-15
SLIDE 15

5-yr running mean

Kenora Kenora Temperature vs. Diatom trends emperature vs. Diatom trends

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Annual Temperature (ºC)

  • 1

1 2 3 4 5 6 y = 0.0112x + 1.8032

1.19 ºC  since 1899

5-yr running mean

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Winter Temperature (ºC)

  • 22
  • 20
  • 18
  • 16
  • 14
  • 12
  • 10
  • 8
  • 6

y = 0.0216x - 16.136

2.29 ºC  since 1899

Update on research Update on research

  • 96º
  • 95º
  • 94º
  • 93º

49º 50º

Kenora Kenora Minnesota O n t a r i

  • Manitoba

Planktonic Cyclotella species

Rühland et al.: in preparation.

slide-16
SLIDE 16

5-yr running mean

Kenora Kenora Temperature vs. Diatom trends emperature vs. Diatom trends

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Annual Temperature (ºC)

  • 1

1 2 3 4 5 6 y = 0.0112x + 1.8032

1.19 ºC  since 1899

5-yr running mean

Year AD

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

Winter Temperature (ºC)

  • 22
  • 20
  • 18
  • 16
  • 14
  • 12
  • 10
  • 8
  • 6

y = 0.0216x - 16.136

2.29 ºC  since 1899

Update on research Update on research

  • 96º
  • 95º
  • 94º
  • 93º

49º 50º

Kenora Kenora Minnesota O n t a r i

  • Manitoba

Annual Temperature (ºC)

1.5 2.0 2.5 3.0 3.5 4.0 4.5

Cyclotella (%)

10 20 30 40

R=0.62

1 9 1 9 1 1 9 2 1 9 3 1 9 4 1 9 5 1 9 6 1 9 7 1 9 8 1 9 9 2 2 1

1 2 3 4 2 4 6 8

Annual Temperature % Cyclotella species

R=0.74 Whitefish Bay Reference Bigstone Bay Impact

Planktonic Cyclotella species

Rühland et al.: in preparation.

slide-17
SLIDE 17

1960 1970 1980 1990 2000 2010 180 190 200 210 220 230 240 250 260 y = 0.6556x + 203.64

Year AD # ice-free days

Ice-free period has increased by 27.7 days since 1964 Corresponds to increases in Kenora temperature

1960 180 190 200 210 220 230 240 250 260

# ice-free days

1970 1980

Year AD

1990 2000 2010 1 2 3 4 5 6

Temperature (ºC)

R = 0.77

# Ice-free Days Annual Temperature

27.7 days

Update on research

Whitefi Whitefish Bay Ice-out vs. Diatom trends sh Bay Ice-out vs. Diatom trends

Update on research Update on research

Rühland et al.: in preparation.

slide-18
SLIDE 18

PCA sample scores (SD units)

Whitefish Bay

116 118 120 122 124 126 128 130 132 134

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0

Ice-out day of year PCA sample scores

R = - 0.78 R = - 0.66

PP-1

Ice-out day of year

118 120 122 124 126 128 130 132

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0 2.5

1 9 6 5 1 9 7 1 9 7 5 1 9 8 1 9 8 5 1 9 9 1 9 9 5 2 2 5

0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 118 120 122 124 126 128 130 132

Bigstone Bay

R = - 0.88

Year AD

Whitefi Whitefish Bay Ice-out vs. Diatom trends sh Bay Ice-out vs. Diatom trends

Update on research Update on research

1960 1970 1980 1990 2000 2010 180 190 200 210 220 230 240 250 260 y = 0.6556x + 203.64

Year AD

# ice-free days

27.7 days since 1964

Rühland et al.: in preparation.

slide-19
SLIDE 19

Whitefish Bay

Ice-out day of year

116 120 124 128 132 136

Cyclotella species (%)

10 20 30 40

Ice out day of year % Cyclotella

R =

  • 0.67

Year AD

1 9 7 1 9 7 5 1 9 8 1 9 8 5 1 9 9 1 9 9 5 2 2 5

120 124 128 132 1 2 3 4 5 6 7 8

R = - 0.84

Bigstone Bay

PCA sample scores (SD units)

Whitefish Bay

116 118 120 122 124 126 128 130 132 134

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0

Ice-out day of year PCA sample scores

R = - 0.78 R = - 0.66

PP-1

Ice-out day of year

118 120 122 124 126 128 130 132

  • 1.0
  • 0.5

0.0 0.5 1.0 1.5 2.0 2.5

1 9 6 5 1 9 7 1 9 7 5 1 9 8 1 9 8 5 1 9 9 1 9 9 5 2 2 5

0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 118 120 122 124 126 128 130 132

Bigstone Bay

R = - 0.88

Year AD

Whitefi Whitefish Bay Ice-out vs. Diatom trends sh Bay Ice-out vs. Diatom trends

Update on research Update on research

1960 1970 1980 1990 2000 2010 180 190 200 210 220 230 240 250 260 y = 0.6556x + 203.64

Year AD

# ice-free days

27.7 days since 1964

Planktonic Cyclotella species

Rühland et al.: in preparation.

slide-20
SLIDE 20

Year (AD) PP1-Impact Site Bigstone Bay-Impact Site Whitefish Bay-Reference Site

1890 1895 1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 0.0100.0150.0200.0250.0300.0350.0400.0450.050

Chla (mg/g dry wt)

Spectrally-inferred Chl Spectrally-inferred Chla trends: all sites trends: all sites

Update on research Update on research

Rühland et al.: in preparation.

slide-21
SLIDE 21

Winter Temperature (ºC)

0.018 0.020 0.022 0.024 0.026 0.028 0.030

PP1

0.020 0.025 0.030 0.035 0.040 0.045 0.050 1900 1920 1940 1960 1980 2000 2020

  • 17
  • 16
  • 15
  • 14
  • 13
  • 12

R=0.78

Bigstone Bay

  • 17
  • 16
  • 15
  • 14
  • 13
  • 12

R=0.90

Winter Temperature trends Winter Temperature trends

Chla (mg/g dry wt) PP1-Impact Site Bigstone Bay-Impact Site Whitefish Bay-Reference Site Year (AD)

1890 1895 1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 0.0100.0150.0200.025

Chla (mg/g dry wt)

0.0300.0350.0400.0450.050

Spectrally-inferred Chl Spectrally-inferred Chla trends: all sites trends: all sites

Update on research Update on research

Rühland et al.: in preparation.

slide-22
SLIDE 22

1900 1920 1940 1960 1980 2000 2020 0.012 0.014 0.016 0.018 0.020 0.022 0.024 0.026

  • 18
  • 17
  • 16
  • 15
  • 14
  • 13
  • 12

R=- 0.02

Whitefish Bay

Chla (mg/g dry wt) Winter Temperature (ºC) Winter Temperature (ºC)

0.018 0.020 0.022 0.024 0.026 0.028 0.030

PP1

0.020 0.025 0.030 0.035 0.040 0.045 0.050 1900 1920 1940 1960 1980 2000 2020

  • 17
  • 16
  • 15
  • 14
  • 13
  • 12

R=0.78

Bigstone Bay

  • 17
  • 16
  • 15
  • 14
  • 13
  • 12

R=0.90

Winter Temperature trends Winter Temperature trends

Chla (mg/g dry wt) PP1-Impact Site Bigstone Bay-Impact Site Whitefish Bay-Reference Site Year (AD)

1890 1895 1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 0.0100.0150.0200.0250.0300.0350.0400.0450.050

Chla (mg/g dry wt)

Spectrally-inferred Chl Spectrally-inferred Chla trends: all sites trends: all sites

Update on research Update on research

Rühland et al.: in preparation.

slide-23
SLIDE 23

Summary & Conclusions Summary & Conclusions

Update on research Update on research

  • Historically, TP has been relatively high and variable at all 3

Historically, TP has been relatively high and variable at all 3 sites sites

  • no evidence for recent increases in TP concentrations
slide-24
SLIDE 24

Summary & Conclusions Summary & Conclusions

Update on research Update on research

  • Historically, TP has been relatively high and variable at all 3 sites
  • no evidence for recent increases in TP concentrations
  • Temperature & Ice

Temperature & Ice-

  • out trends linked to diatom changes
  • ut trends linked to diatom changes –

–

  • esp. last ~20
  • esp. last ~20-
  • 30 yrs

30 yrs

  • all sites show important relationships to warming
  • as expected this is most clearly expressed in the reference site
slide-25
SLIDE 25

Summary & Conclusions Summary & Conclusions

Update on research Update on research

  • Historically, TP has been relatively high and variable at all 3 sites
  • no evidence for recent increases in TP concentrations
  • Temperature & Ice-out trends linked to diatom changes – esp. last ~20-30 yrs
  • all sites show important relationships to warming
  • as expected this is most clearly expressed in the reference site
  • Increase in 1

Increase in 10 production ( production (Chl Chl a) at impact sites (no trend at reference site) a) at impact sites (no trend at reference site)

  • strong correlations to recent warming
  • likely tracking algal blooms
  • synergistic effects between nutrients & warming may be triggering algal blooms
slide-26
SLIDE 26

Summary & Conclusions Summary & Conclusions

Update on research Update on research

  • Historically, TP has been relatively high and variable at all 3 sites
  • no evidence for recent increases in TP concentrations
  • Temperature & Ice-out trends linked to diatom changes – esp. last ~20-30 yrs
  • all sites show important relationships to warming
  • as expected this is most clearly expressed in the reference site
  • Increase in 1o production (Chl a) at impact sites (no trend at reference site)
  • strong correlations to recent warming
  • likely tracking algal blooms
  • synergistic effects between nutrients & warming may be triggering algal blooms
  • Recent diatom shifts in LOW best explained by recent warming & a

Recent diatom shifts in LOW best explained by recent warming & associated ssociated limnological limnological changes changes

slide-27
SLIDE 27

Refereed papers: LOW paleo Refereed papers: LOW paleo studies (so far) studies (so far)

1) Pla, S., Paterson, A., Smol J. (2005). Spatial variability in water quality and surface sediment diatom assemblages in a complex lake basin: Lake of the Woods, Ontario, Canada. J. Great Lakes Res. 31: 253-266. 2) Yang, Z., Teller, J. (2005). Modeling the history of Lake of the Woods since 11,000 cal yr B.P. using

  • GIS. J. Paleolimnol. 33: 483-498.

3) Reavie E., N. Baratono (2007). Multi-core investigation of a lotic bay of Lake of the Woods (Minnesota, USA) impacted by cultural development. J. Paleolimnol. 38: 137-156. 4) Suchy, K., Hann, B. (2007). Using microfossil remains in lake sediments to examine the invasion of Eubosmina coregoni (Cladocera, Bosminidae) in Lake of the Woods, Ontario, Canada. J. Great Lakes Res. 33: 867-874. ******************COMING SOON*********************** 1) Serieyssol C., Edlund, M., Kallemeyn L. (submitted). Impacts of settlement, damming, and hydromanagement in a large, boreal lake: a paleolimnological Before-After, Control-Impact study. 2) Rühland, K., Paterson, A, Smol, J. (submitted). Hemispheric-scale patterns of climate-related increases in planktonic diatoms from North American and European lakes. 3) Rühland, K., Paterson, A., Hargan, K., Michelutti, N., Clark, B., Smol, J. (submitted). Evidence for linkages between recent warming and diatom community reorganization in the Lake of the Woods, Ontario, Canada.