Wetland Loss – A Closer Look at Wetland Loss Research Activities in

Jamaica Bay

Patti Rafferty and Charles RomanNational Park Service

Northeast Region

Wetland Loss in Jamaica Bay• Research: Rate of loss

Sediment Elevation

Biogeochemistry

Sediment Budget

Circulation

• Restoration: Big Egg

Elders Point East

• New Initiatives and Research Needs

Marsh Island Loss in Jamaica Bay

Figure from GATE & Jamaica Bay Watershed Protection Plan Advisory Committee, 2007

1951-2003

Salt Marsh in 1951

Salt Marsh in 2003

Marsh lost to filling railroads, street uplands and pond impoundments (not included in loss calculations)

Jamaica Bay Marsh Islands: Total Vegetated Marsh

1951 1974 1989 2003

Vegetated Marsh(acres)

2347 1610 1333 876

Jamaica Bay Marsh Islands: Rate of Marsh Loss

Average Rate of Loss(acres/year)

17 18 33

1951-1974 1974-1989 1989-2003

Marsh Island Loss in Jamaica Bay

Tables from GATE & JBWPPAC, 2007

Marsh Elevation & Accretion

• Evaluate relationship between marsh elevation change and rates of relative sea level rise• Understand the surface and subsurface processes that influence marsh elevation change

Figure from McKee and Patrick, 1988

Why is marsh elevation important?

Peat

Sediment Estuary

Vertical accretion

horizon marker

Marsh surfaceelevation

Subsurface elevation change• organic accumulation• decomposition• subsidence• porewater storage

6 – 15m deep

Surface Elevation Table (SET)

benchmarkpipe

4.78 mm y-1 (JB-BB - deteriorating)

4.39 mm y-1 (JB-JoCo - stable)

Unpublished data Cahoon & Lynch, USGS

Marsh Surface Elevation Change

4.78 mm y-1 (JB-BB - deteriorating)

4.39 mm y-1 (JB-JoCo - stable)

Unpublished data Cahoon & Lynch, USGS

Marsh Surface Elevation Change

140 y sea-level rise 2.73 mm y-1 (Battery)

Big Egg Marsh Experimental Restoration

Photo courtesy of George Frame

Big Egg Marsh Restoration

Restored Marsh

Reference Marsh 2007Fall 2003

Fall 2004

Fall 2006

Big Egg Marsh Restoration Monitoring

• Determine factors contributing to the success or failure of the restoration• Evaluate various restoration techniques • Identify problems requiring remedial action (adaptive management)• Better understand factors contributing to salt marsh loss

Will the restored Big Egg Marsh be sustainable?

2003 2004 2005 2006 2007 2008

0

100

200

300

400

500

mm

Year

Big Egg Spray Big Egg Reference

Unpublished data Cahoon & Lynch, USGS

2004 2005 2006 2007 2008

-35

-30

-25

-20

-15

-10

-5

0

5

10

15

20

25

30

mm

Date

Accretion Elevation

Elders Point East MarshExperimental Restoration

Photo courtesy of Alex Kolker

Elders Point Marsh Restoration

2006

2007

2007

2008

Elders Point East Marsh Restoration Monitoring

• Determine factors contributing to the success or failure of the restoration• Evaluate various planting techniques • Identify problems requiring remedial action (adaptive management)• Better understand factors contributing to salt marsh loss

Figure from Craft et al. 2003

How does restoration monitoring contribute to an understanding of wetland loss?

0

200

400

600

800

1000

1200

Elders East JoCo

200520062007

Biom

ass

(gm

-2)

Sample SiteElders East JoCo

Sample Site and Depth Interval

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0-15 15-30 0-15 15-30

200520062007

Mean Total Biomass

Unpublished data Rafferty, NPS

Aboveground Belowground

No Fertilizer and Fertilizer Plots

Biom

ass

(gm

-2)

0

20

40

60

80

100

120

No Fertilizer Fertilizer0

20

40

60

80

100

120

140

0-15 15-30 0-15 15-30

Biom

ass

(gm

-2)

No Fertilizer Fertilizer

Treatment and Sample Depth

Unpublished data Rafferty, NPS

Treatment

Biogeochemistry

• Evaluate the role of nutrients and hydrogen sulfide in marsh loss• Characterize the biogeochemistry of Jamaica Bay salt marsh islands• Understand the evolution of biogeochemical processes in a newly restored salt marsh

Porewater Nutrients and Hydrogen Sulfide

Unpublished data Cochran, Stony Brook University

0

10

20

30

40

50

0 1000 2000 3000

NH4 (μmol l-1)

Dept

h (c

m)

0

10

20

30

40

50

0 5 10 15 20

N+N (μmol l-1)

Dep

th (c

m)

0

10

20

30

40

50

0 50 100 150 200 250 300

PO4 (μmol l-1)

Dept

h (c

m)

0

10

20

30

40

50

0 2 4 6 8

HS (mmol l-1)

Dep

th (c

m)

Elders - restoredJoCo - reference

On the horizon

• Develop a bathymetric map of Jamaica Bay

• Determine if nitrogen loading has altered marsh function and sediment accretion on marsh islands

• Marsh island restoration – Elders Point West and Yellow Bar Hassock

Thoughts on Future Research

• Elevation data to determine hydroperiod and assess vulnerability of individual marsh islands to sea level rise

• Assess historic nutrient loads and other urbanization factors inrelation to marsh loss statistics

• Role of dense Ulva mats in trapping resuspended sediment• Develop comprehensive model to integrate our accumulating knowledge

on JB marsh loss (e.g., nutrients, altered circulation, sea-level rise, Rockaway barrier changing geomorphology, others)

Causes of Marsh Loss

Jamaica Bay Habitat Functions• Compare the functions of marsh vs. mudflat in terms of bird

utilization, nursery area, benthic community support, wave and storm energy attenuation, etc.

http://www.nps.gov/gate/naturescience/upload/JBAY-Research%20Opportunities.pdf