Atm ospheric Deposition, Atm ospheric Deposition, Transport, - - PowerPoint PPT Presentation

Atm ospheric Deposition, Atm ospheric Deposition, Transport, Transform ations Transport, Transform ations Fate and Bioavailability of Fate and Bioavailability of Mercury in Forested Mercury in Forested W atersheds of the W atersheds of the Northeastern U.S. Northeastern U.S. , ,

Outline Outline

• Upland transformations

Upland transformations

• Wetland

Wetland-

• surface water dynamics

surface water dynamics

• Patterns in aquatic biota

Patterns in aquatic biota

• MCM

MCM-

• HD

HD – – Model calculations Model calculations

Collaborators Collaborators

• Ron Munson

Ron Munson -

• Tetra Tech

Tetra Tech

• Jason Demers

Jason Demers -

• Cornell

Cornell

• Neil

Neil Kamman Kamman -

• VT DEC

VT DEC

• David Evers

David Evers -

• Biodiversity Research Institute

Biodiversity Research Institute

• Tom

Tom Holsen Holsen, Hyun , Hyun-

• Deok

Deok Choi Choi – – Clarkson Clarkson

• Eric Miller

Eric Miller – – Ecosystem Research Group Ecosystem Research Group

• Brian

Brian Branfireum Branfireum -

• Toronto

Toronto

Site Description Site Description

Sunday Lake Watershed Arbutus Lake Watershed

Adirondack Park

Study Region and Mercury Datasets

Evers 2005. Mercury Connections.

Throughfall Litterfall Deposition Canopy air Canopy air Soil Leaf tissue Leaf tissue Evasion Soil Soil Soil Water Soil Water Root tissue Root tissue

Year

1999 2000 2001 2002 2003 2004 2005

Total Hg (ng/L)

2 4 6 8 10

Huntington Forest Biscuit Brook

Wet Hg Deposition - 6.9 ug/m2-yr

Forest Ecosystem Hg Mass Balance Forest Ecosystem Hg Mass Balance

24.3

Forest Ecosystem Hg Mass Balance Forest Ecosystem Hg Mass Balance

Mercury Flux from Soil Surface Mercury Flux from Soil Surface

Time of Day

13:00: 17:00: 21:00: 01:00: 05:00: 09:00: 13:00: 17:00: 21:00: 01:00: 05:00: 09:00: 13:00:

THg Flux [ng m-2 hr-1]

5 10 15 20 25

Relative Humidity [%]

40 50 60 70 80 90 100

Temperature [oC]

16 18 20 22 24 26 28 Hg Flux RH [%] Temperature [oC]

From Miller et al. 2 0 0 5 .

Mercury in Fish by Species Mercury in Fish by Species

Lake-w atersheds vary in their sensitivity to m ercury inputs based on: 1 . Land Cover ( e.g., forest, w etlands) 2 . Hydrologic flow paths 3 . Aquatic productivity

Mercury Cycling Model for Headw ater Mercury Cycling Model for Headw ater Drainage Lakes ( MCM Drainage Lakes ( MCM -

• HD)

HD)

Precipit at ion Rain ET Part icle Capt ure Throughfall

CANOPY INTERACTIONS WETLAND WATER QUALITY/HYDROLOGY SOIL HYDROLOGIC PROCESSES ATMOSPHERIC DEPOSITION WETLAND Hg PROCESSES

Organic Complexat ion Sorpt ion Clay

R-SH Hg R-SH Hg Hg Hg … …

SOIL CHEMICAL PROCESSES

Volat ilizat ion

Hg (II) Hg (O) CH3 -Hg

R e d u c t i

• n

M e t h y l a t i

• n

D e m e t h y l a t i

• n

Sunday Lake I nlet Calibration: Sunday Lake I nlet Calibration: Total Hg Total Hg

2 4 6 8 10 Sep/1/99 Aug/31/00 Aug/31/01 Sep/1/02 Simulated Observed

Total Hg (ng/l)

Date

Sunday Lake I nlet Calibration: Sunday Lake I nlet Calibration: Methyl Hg Methyl Hg

1 2 3 Sep/1/99 Aug/31/00 Aug/31/01 Sep/1/02 Simulated Observed

Methyl Hg (ng/l)

Date

Sunday Lake: Sim ulated Response of Fish Sunday Lake: Sim ulated Response of Fish Hg to 1 5 % and 5 0 % Decreases in Hg to 1 5 % and 5 0 % Decreases in Atm ospheric Hg Deposition Atm ospheric Hg Deposition

0.2 0.4 0.6 0.8 1 1.2 100 200 300 400 500 Mercury Deposition at Current Level Mercury Deposition Reduced 50% Mercury Deposition Reduced 15% Yellow Perch Hg (ug/g) Simulation Year

Conclusions Conclusions

• The forest canopy enhances Hg deposition

The forest canopy enhances Hg deposition

• Hg inputs are retained in soil, re

Hg inputs are retained in soil, re-

• emitted

emitted to the atmosphere or lost with drainage to the atmosphere or lost with drainage

• Wetlands enhance the supply and

Wetlands enhance the supply and transport of transport of MeHg MeHg

• Marked bioaccumulation of

Marked bioaccumulation of MeHg MeHg occurs in

• ccurs in

the aquatic food chain the aquatic food chain

• The western Adirondacks is a Hg “hotspot”

The western Adirondacks is a Hg “hotspot”

Research Needs Research Needs

• Dry deposition (total deposition)

Dry deposition (total deposition)

• Fate of soil Hg

Fate of soil Hg

• Soil re

Soil re-

• emissions

emissions

• Response of fish Hg to changes in Hg

Response of fish Hg to changes in Hg inputs and acid rain inputs and acid rain