Abstract
Aerial photographs and GIS analysis were used to map the distribution of tidal marsh vegetation along the salinity gradients of the estuaries of the Altamaha and Satilla Rivers in coastal Georgia. Vegetation maps were constructed from 1993 U.S. Geological Survey Digital Orthophoto Quarter Quads, 1∶77,000-scale color infrared photographs taken in 1974 and 1∶24,000-scale black and white photographs taken in 1953, Changes between years were identified using a GIS overlay analysis. Four vegetation classifications were identified and groundtruthed with field surveys: salt marsh (areas containing primarilySpartina alterniflora), brackish marsh (Spartina cynosuroides andS. alterniflora), Juncus (Juncus roemerianus), and fresh marsh (Zizania aquatica, Zizaniopsis miliacae, and others). There was no evidence for an upstream shift in marsh vegetation along the longitudinal axis of either estuary over the time frame of this analysis, which implies there has not been a long-term increase in salinity. Although the inland extent of each marsh zone was further upstream in the Satilla than the Altamaha, they corresponded to similar average high tide salinities in each estuary: areas classified as salt marsh occurred from the mouth up to where average high tide salinity in the water was approximately 15 psu;Juncus ranged from 21 to 1 psu; brackish marsh ranged from 15 to 1 psu; and fresh marsh was upstream of 1 psu. Approximately 63% of the 6,786 ha of tidal marsh vegetation mapped in the Altamaha and 75% of the 10,220 ha mapped in the Satilla remained the same in all 3 yr.Juncus was the dominant classification in the intermediate regions of both estuaries, and shifts between areas classified asJuncus and either brackish or salt marsh constituted the primary vegetation change between 1953 and 1993 (87% of the changes observed in the Altamaha and 95% of those in the Satilla). This analysis suggests that the broad distribution of tidal marsh vegetation along these two estuaries is driven by salinity, but that at the local scale these are dynamic systems with a larger number of factors affecting the frequently changing borders of vegetation patches.
Similar content being viewed by others
Literature Cited
Alber, M. andJ. E. Sheldon. 1999a. Use of a date specific method to examine variability in the flushing times of Georgia estuaries.Estuarine, Coastal and Shelf Science 49:469–482.
Alber, M. andJ. E. Sheldon. 1999b. Trends in salinities and flushing times of Georgia estuaries, p. 528–531.In K. Hatcher (ed.), Proceedings of the 1999 Georgia Water Resources Conference. The Institute of Ecology, University of Georgia, Athens, Georgia.
Bertness, M. D. andA. M. Ellison. 1987. Determinants of pattern in a New England salt marsh plant community.Ecological Monographs 57:129–147.
Brinson, M. M. andR. R. Christian. 1999. Stability ofJuncus roemerianus patches in a salt marsh.Wetlands 19:65–70.
Bureau of the Budget. 1947. U.S. National Map Accuracy Standards. U.S. Geological Survey website http://rockyweb.cr.usgs.gov/nmpstds/nmas647.html
Clewell, A. F. 1997. Vegetation, pp. 77–109.In C. L. Coultas and Y. P. Hsieh (eds.), Ecology and Management of Tidal Marshes: A Model from the Gulf of Mexico. St. Lucie Press, Delray Beach, Florida.
Cowen, D. J., J. R. Jensen, P. J. Bresnahan, G. B. Ehler, D. Graves, X. Q. Huang, C. Wiesner andH. E. Mackey. 1995. The design and implementation of an integrated Geographic Information System for environmental applications.Photogrammetric Engineering and Remote Sensing 61:1393–1404.
Cracknell, A. P. 1999. Remote sensing techniques in estuaries and coastal zones—An update.International Journal of Remote Sensing 19:485–496.
Eleuterius, L. N. 1976. The distribution ofJuncus roemerianus in the salt marshes of North America.Chesapeake Science 17:289–292.
Eleuterius, L. N. andC. K. Eleuterius. 1979. Tide levels and salt marsh zonation.Bulletin of Marine Science 29:394–400.
Eleuterius, L. N. 1984. Autoecology of the black needlerush,Juncus roemerianus.Gulf Research Reports 7:339–350.
Field, R. T. andK. R. Phillipp. 2000. Vegetation changes in the freshwater tidal marsh of the Delaware estuary.Wetlands Ecology and Management 8:79–88.
Gallagher, J. L. andR. J. Reimold. 1973. Tidal marsh plant distribution and productivity patterns from the sea to fresh water—A challenge in resolution and discrimination, p. 166–183.In Proceedings 4th Biennial Workshop on Color Aerial Photography. American Society of Photogrammetry, Falls Church, Virginia and University of Maine, Orono, Maine.
Greenland, D. 2001. Multiyear variation of temperature and precipitation in the coastal states of the southeastern U.S.Southeastern Geographer 41:36–52.
Hackney, C. T. andA. A. de la Cruz. 1980. In situ decomposition of roots and rhizomes of two tidal marsh plants.Ecology 61:226–231.
Hackney, C. T., S. Brady, L. Stemmy, M. Boris, C. Dennis, T. Hancock, M. O'Bryon, C. Tilton, andE. Barbee. 1996. Does intertidal vegetation indicate specific soil and hydrologic conditions.Wetlands 16:89–94.
Hardisky, M. A., M. F. Gross, andV. Klemas. 1986. Remote sensing of coastal wetlands.Bioscience 36:453–460.
Jensen, J. R., D. J. Cowen, J. D. Althausen, S. Narumalani, andO. Weatherbee. 1993. An evaluation of the CoastWatch change detection protocol in South Carolina.Photogrammetric Engineering and Remote Sensing 59:1039–1046.
Klemas, V. V., J. E. Dobson, R. L. Ferguson, andK. D. Haddad. 1993. A coastal land cover classification system for the NOAA coastwatch change analysis project.Journal of Coastal Research 9:862–872.
Latham, P. J., L. G. Pearlstine, andW. M. Kitchens. 1994. Species association changes across a gradient of freshwater, oligohaline, and mesohaline tidal marshes along the lower Savannah River.Wetlands 14:174–183.
McCormick, C. M. 1999. Mapping exotic vegetation in the Everglades from large-scale aerial photographs.Photogrammetric Engineering and Remote Sensing 65:179–184.
National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center. “Descriptive Summary of the Changes in Coastal Georgia, January 20, 1992, to December 19, 1997.” http://www.csc.noaa/gov/crs/lca/georgia.html.
NOAA. 2001 Sea Level Variations of the U.S. 1854–1999. National Ocean Service Center for Operational Oceanographic Products and Services (NOS CO-OPS). NOAA Technical Report 36. Silver Spring, Maryland. http://co-ops.nos.noaa.gov/publication/techrpt36doc.pdf
Odum, W. E. 1988. Comparative ecology of tidal fresswater and salt marshes.Annual Review of Ecology and Systematics 19:147–176.
Pearlstine, L. G., W. M. Kitchens, P. J. Latham, andR. D. Bartleson. 1993. Tide gate influences on a tidal marsh.Water Resources Bulletin 29:1009–1019.
Perry, J. E. andC. H. Hershner. 1999. Temporal changes in the vegetation pattern in a tidal freshwater marsh.Wetlands 19:90–99.
Ramsey, E. W., G. A. Nelson, andS. K. Sapkota. 2001. Coastal change analysis program implemented in Louisiana.Journal of Coastal Research 17:53–71.
Rice, D., J. Rooth, andJ. C. Stevenson. 2000. Colonization and expansion ofPhragmites australis in upper Chesapeake Bay tidal marshes.Wetlands 10:280–299.
Roman, C. T., W. A. Niering, andR. S. Warren. 1984. Salt marsh vegetation change in response to tidal restriction.Environmental Management 8:141–150.
Sandifer, P. A., J. V. Miglarese, D. R. Calder, J. J. Manzi, andL. A. Barclay. 1980. Ecological Characterization of the Sea Island Coastal Region of South Carolina and Georgia, Volume 3, U.S. Fish and Wildlife Service, U.S. Department of the Interior, Washington, D.C.
Schubauer, J. P. andC. S. Hopkinson. 1984. Above-and belowground emergent macrophyte production and turnover in a coastal marsh ecosystem, Georgia.Limnology and Oceanography 29:1052–1065.
Schuyler, A. E., S. B. Andersen, andV. J. Kolaga. 1993. Plant zonation in the tidal protion of the Delaware River.Proceedings of the Academy of Natural Sciences of Philadelphia 144:263–266.
Shay, J. M., P. M. de Geus, andM. R. Kapinga. 1999. Changes in shoreline vegetation over a 50-year period in the Delta Marsh, Manitoba in response to water levels.Wetlands 19:413–425.
Ungar, I. A. 1998. Are biotic factors significant in influencing the distribution of halophytes in saline habitats?The Botanical Review 64:176–199.
Visser, J. M., C. E. Sasser, R. H. Chabreck, andR. G. Linscombe. 2002. The impact of a severe drought on the vegetation of a subtropical estuary.Estuaries 25:1184–1195.
White, D. A., T. E. Weiss, J. M. Trapani, andL. B. Thien. 1979. Productivity and decomposition of the dominant salt marsh plants in Louisiana.Ecology 59:751–759.
Wiegert, R. G. andB. J. Freeman. 1990. Tidal salt marshes of the southeast Atlantic coast: A community profiles. Biological Report 85. U.S. Fish and Wildlife Service, Washington, D.C.
Woerner, L. S. andC. T. Hackney. 1997. Distribution ofJuncus roemerianus in North Carolina tidal marshes: The importance of physical and biotic variables.Wetlands 17:284–291.
Source of Unpublished Materials
Blanton, J. unpublished data. Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, Georgia 31411.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Higinbotham, C.B., Alber, M. & Chalmers, A.G. Analysis of tidal marsh vegetation patterns in two Georgia estuaries using aerial photography and GIS. Estuaries 27, 670–683 (2004). https://doi.org/10.1007/BF02907652
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02907652