1. Coastal Communities and Processes: Beach and Dunes Introduction to Coastal Management

2. Coastal Communities and Processes Beach and DunesBeach and Dunes Shrub Thicket and Maritime ForestShrub Thicket and Maritime Forest Freshwater WetlandsFreshwater Wetlands Tidal MarshTidal Marsh Estuarine Waters/Sand and Mud FlatsEstuarine Waters/Sand and Mud Flats

3. Barrier Island transect from ocean to sound

4. Beach, Dunes and Shrub Thicket Cumberland Island, Georgia

5. Dune Formation SandWindObject Elements required for dune formationElements required for dune formation

6. Dune Formation Sand, moved by the process of saltation, accumulates around objects including vegetation and flotsam

7. American Beachgrass (Ammophila breviligulata)

8. Sea Oats (Uniola paniculata)

9. Panic Grass (Panicum amarum)

10. Saltmeadow Cordgrass (Spartina patens)

11. Sea Elder (Iva imbricata)

12. Primary Dunes Most seawardMost seaward Unmodified dunesUnmodified dunes

13. Secondary Dunes large landward duneslarge landward dunes modified primary dunesmodified primary dunes

14. Strand Line or Wrack Line Line of debris at spring tideLine of debris at spring tide Debris is called “wrack”Debris is called “wrack” Most dunes form hereMost dunes form here

15. Strand Line or Wrack Line Large quantities of sand moved across strandLarge quantities of sand moved across strand Common on prograding (growing) beachesCommon on prograding (growing) beaches Rare on eroding beachesRare on eroding beaches

16. Dune Environments Youngest strand lines lie most seawardYoungest strand lines lie most seaward Multiple dune ridges form as strand lines are colonizedMultiple dune ridges form as strand lines are colonized Oldest - - - - - - > Youngest

17. Dune Environments Dunes and colonizing plants grow in concertDunes and colonizing plants grow in concert Year 3 Year 2 Year1

18. Dune Environmental Conditions Low soil nutrients (N and P)Low soil nutrients (N and P) Desiccating windsDesiccating winds Blowing sandBlowing sand

19. Dune Environmental Conditions Air and soil temperatures are highly variableAir and soil temperatures are highly variable

20. Dune Processes Unvegetated dunes “migrate” or move from 15 m annuallyUnvegetated dunes “migrate” or move from 15 m annually Migrating dunes engulf surroundingsMigrating dunes engulf surroundings  Natural revegetation a long term process

21. Blowouts Occur when vegetation mantle is destroyedOccur when vegetation mantle is destroyed Difficult to stop, once startedDifficult to stop, once started Creates environment called “slack”Creates environment called “slack” blowout

22. Natural and Man-induced Impacts on Dunes Oceanic overwashOceanic overwash “erosion”“erosion” Washovers

23. Natural and Man-induced Impacts on Dunes Off-road vehicle (ORV) trafficOff-road vehicle (ORV) traffic Sand fencing: wooden, brush, treesSand fencing: wooden, brush, trees

24. Salt Aerosol Impact on Plants Source of salt aerosol (ocean side)

25. Source of Salt Aerosols Salt Aerosols

26. Salt Aerosol Impacts Salt aerosol effects on plants Salt aerosol source this side

27. Salt Aerosol Impact on Plants Generally decreases from strand line, landwardGenerally decreases from strand line, landward Highest on foredunesHighest on foredunes Lowest in slacks and lee of dunesLowest in slacks and lee of dunes

28. Shrub Thicket Environments Early colonizers (survive low nutrients)Early colonizers (survive low nutrients) Best examples are in dune slacksBest examples are in dune slacks Reduced salt aerosol environment allows arborescent vegetation to flourishReduced salt aerosol environment allows arborescent vegetation to flourish

29. Wax Myrtle (Myrica pennsylvanica) Northern Bayberry is common in thickets from Cape Hatteras northward into New EnglandNorthern Bayberry is common in thickets from Cape Hatteras northward into New England Bayberry candles are made from the waxy coating on the berriesBayberry candles are made from the waxy coating on the berries

30. Yaupon (Ilex vomitoria)