Building ecosystem resilience to sea- level rise on the ... · 1US CCSP 2009, 2Kemp et al. 2009. ... Installation of sheet pile ditch plug Secondary drainage ditch. Point Peter Road

Brian Boutin, PhDNovember 16, 2010

© John Warner© Aaron McCall

Building ecosystem resilience to sea-level rise on the Albemarle Peninsula of North Carolina through

restoration and creation of coastal habitat complexes

Vulnerability in NE North Carolina

Susceptible to hurricanes and nor’easters

Extensive ditching and draining of wetlands

Extremely low elevation Third most vulnerable

region to impacts of sea-level rise in North America1

RSLR 4 mm/y along the ocean3.0-3.3 mm/y2 in the

estuary

1US CCSP 2009, 2Kemp et al. 2009

Sea level rise on the Albemarle Peninsula

Why adaptation in NE North Carolina?

Climate change is a long-term and potentially catastrophic stressor to ecosystems

Vulnerability = significant impacts manifest in the near-term Large investment in conservation Dependence of regional economy on natural systems

Direct - tourism; commercial and recreational fishing; hunting Indirect – storm surge protection; water resources; water quality

Maintenance and/or enhancement of ecosystem resilience = maintenance and/or enhancement of ecosystem services Avoidance of ecosystem collapse and assurance of redundancy

Regional and global transferability of lessons learned

Alligator River NWR

Partnership

Objectives: o To ensure that as the ecosystems of the region are inevitably

altered by climate change and sea level rise, they are transformed into ones that remain complex and provide a suite of ecosystem services.

o To demonstrate the need for and the benefits of using natural techniques for climate adaptation.

o To encourage large-scale ecosystem resilience work across this vulnerable landscape.

Primary climate-related impacts

Shoreline erosion InundationHabitat transition Species invasions Saltwater intrusionCatastrophic

wildfire

Wave energy and storm surge attenuation

Strategy: construct fringing oyster reefs along high energy shorelinesMaterials: marl, oyster shell bags, OysterCrete, Reef Balls, EcoSystems

Managed habitat transition

Strategy: strategic plantings of salt- and flood-tolerant vegetation on altered lands.

Shoreline Restore and maintain a

healthy buffer of brackish marsh vegetation

Removal of invasive species e.g. common reed (Phragmites australis)

Inland Establishing stands of

forested wetland species e.g. bald cypress (Taxodiumdistichum (L.) L.C. Rich)

Effects of altered hydrology on the landscape

Lowest elevationsSaltwater intrusion Salt-poisoning of vegetation Soil decomposition through

sulfate reduction Locally: subsidence and

increased inundation; release of N and Hg

Globally: release of CO2 and CH4

Higher elevationsIncremental soil loss OxidationCatastrophic soil loss Ignition

Evans Road fire in PocosinLakes NWR burned over 6 million tons of carbon deposits

Hydrologic manipulation

Strategy: prevent further saltwater intrusion and restore a natural hydrologic regime through use of ditch plugs or water control structures

Initial actions at Alligator River NWR

Point Peter Road demonstration site Four components:

1. Salt-tolerant tree plantings2. Hydrologic manipulation3. Invasive species control4. Offshore oyster reef sills

Significant impacts evident Shoreline erosion

~5 m per y1,2

Invasive species Saltwater intrusion3

Vegetation transition Accessibility Monitoring Education

1Wang and Allen 2008; 2Patel 2009; 3Poulter et al. 2008

Point Peter Road demonstration site

Experimental salt-tolerant tree plantings80 acres total; 40 acres

of plantings; 40 acres of control4 treatments

11, 500 bald cypress; 2,000 black gum; 6,750 pond pine

Plantings occurred March 2010

Point Peter Road demonstration site

Hydrologic manipulationReplacement of water

control structureMajor drainage canalSeries of elevated pipes

with flashboard risers and Tideflex check valve

Three spillways running under the road to encourage sheetflow

Installation of sheet pile ditch plugSecondary drainage ditch

Point Peter Road demonstration site

Invasive species control84 acre abandoned

waterfowl impoundmentEradication of 11.5 acres

of Phragmites australisDoes invasive species

control increase vulnerability?

Is invasive species control feasible on this landscape?

Herbicide application completed October 2010

Point Peter Road demonstration site

Offshore oyster reef sillsMarl

400 linear feet in 100 feet sections; 10 feet wide; 3 feet tall

Reefs installed June 2010

Oyster shell bags400 linear feet in 100 feet

sections; 10 feet wide; 3 feet tall

Monitoring Program

Water Quality Temperature, salinity,

dissolved oxygen, pH, Secchidepth

Water Flows Velocity and direction

Hydrology Water table levels

Erosion Shoreline migration

Soil Accretion/subsidence Bulk density Carbon content

Vegetation Seedling survival Seedling growth Phragmites extent Phragmites stem density

Fauna Nekton and mobile epibenthos

presence/absence Oyster density Oyster size frequency

Water Quality

Technique(s) Water quality data

loggersSample frequency 3 h

Sample sites Four sites

Water Quality: 2010

Scaling up future restoration efforts

Albemarle PeninsulaGull Rock Game

LandsPocosin Lakes, Swan

Quarter, and Mattamuskeet NWRs

Outer BanksSouth Nags Head

WoodsPea Island NWRCape Hatteras

National Seashore

Ditch plug, marl reefs, and native marsh plantings

Shell bag reefs

Ditch plug

Marl reefs and native marsh plantings

Acknowledgements

The Nature Conservancy: Aaron McCall, Jennifer Gilbreath,

Kate Murray, Chuck Peoples, Rick Studenmund, interns

USFWS: Mike Bryant, Dennis Stewart,

Scott Lanier, Alligator River NWR fire crew

Contact Information:Brian Boutin, Ph.D.The Nature ConservancyNorth Carolina ChapterPh: 252-441-2525, ext. 28E-mail: [email protected]

Funding Duke Energy TNC-NOAA Community-

based Restoration Program

SARP-NOAA Community-based Restoration Program

Albemarle-Pamlico National Estuary Program

Wildlife Conservation Society Wildlife Action Opportunities Fund

Private donations