Climate Change and Coastal Wetlands

Presented by: Sidrotun Naim

Susanna Pearlstein Valerie Herman

Matt Carter

Global Natural Disaster

US Coastal and Marine Facts

95,000 miles of coastlines3.4 million square miles of ocean53% of US population live on the 17% of land in

the coastal zonesGlobal sea level rise: 4-8 inches in centuryEstimation: additional 19 inches by 2100

How coastal and marine environments are linked to

our climate

Shoreline erosion and Human communities

Threats to Estuarine Health

Estuaries are extremely productive ecosystemsIncreased run-off would deliver increased

amounts of nutrients such as nitrogen and phosphorus

Decreased run-off would reduce flushing, decrease the size of nursery zones, allowing predators to penetrate

Coastal Wetland Survival

Coral Reef Die Offs

Stresses on Marine Fisheries

Annual Shoreline Change

WetlandsChapter 11

Methane, CH4, emitters20-25% global emissions50% of world wetlands LOST, methane emissions

are increasing, anthropomorphic causes21 times more effective greenhouse gas than CO2

Carbon sequestration20-30% stored in wetlandsPeat depositsPermafrostRestored & created wetlands

Mid Atlantic Coastal (MAC) Region

Poor water qualityCoastal Squeeze

Heavily Populated!

http://www.epa.gov/climatechange/effects/coastal/index.html

Delaware Bay1.6% of DE lost

21% of marsh land flooded But<1% of affected area Is developed

Chesapeake BaySalt water marshes today lack

Sediment Oxygen Organic matter accumulation

Due to: Poor water quality

DamsFarmland abandonment

Now add climate change….

Most hypoxic estuary in MACFresh water marshes have high river sediment

influxesSteep topography, sea level rise will increase

erosion

Management & WarningsWetlands will be protected if they fall under

socially significant areas

Repeating the inland floodplain experienceFederal subsides for dynamic & hazardous zonesStructures to control hazards & sea level rise Increasing vulnerability

Chemical and Biological Changes

Extreme weather events and rising sea level alters:Salinity Ionic ExchangespHMicrobial CommunitiesOrganic and Inorganic Content

Nutrient ExchangesEarlier litterfall3 - 5 times as much N, Mg, P, KTransported during runoff /flooding Nutrient uptake is hindered by:

UprootingSwayingWater logging

Damages to Plants/Animals

“Woody vegetation” is damaged more than “herbaceous vegetation”

Breakage increases infestation Microbial community differs in aerobic and anaerobic

conditions Water quality directly affects food chain

Hypoxia Image from www.montgomerybotanical.org

Osmotic stress Turbidity Seed distribution Biodiversity

Mitigation

Hurricanes lose their force dramatically as the system moves toward land, therefore wetlands around coast regions provide delicate buffer

zones to slow the storm system down before it reaches more populated regions. The levees in New Orleans are causing dramatic wetland loss.

The levees built to prevent flooding in the cities also prevent recharge of coast wetlands of the Mississippi River Delta. The Delta is cut off from its life force and is being destroyed at a rate of 24 sq. miles a year. Over 1900 sq. miles have disappeared since the 1930s. As the wetlands decrease, the city becomes more and more vulnerable to hurricane without the precious buffer zone.

Fixing the problem is costly and time consuming. Old Christmas trees are strategically place around the delta to collect sediment, and 14 billion dollars is being used for manual sediment recharge and diversion of the Mississippi around the levees to recharge other areas of the delta.

Hurricanes are actually vital for wetland survival in that the storm surge washes and spreads all of the sediment, silt, and nutrients the wetlands of the delta could ever need. A hurricane of smaller proportions could easily do the work of all of the wetland projects.