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publications > open file report > OFR 2006-1355
U.S. Department of the Interior
U.S. Geological Survey
OFR 2006-1355
Marl Prairie Vegetation Response to 20th Century Hydrologic Change
Abstract
We conducted geochronologic and pollen analyses from sediment cores collected in solution
holes within marl prairies of Big Cypress National Preserve to reconstruct vegetation patterns of
the last few centuries and evaluate the stability and longevity of marl prairies within the greater
Everglades ecosystem. Based on radiocarbon dating and pollen biostratigraphy, these cores
contain sediments deposited during the last ~300 years and provide evidence for plant
community composition before and after 20th century water management practices altered flow
patterns throughout the Everglades. Pollen evidence indicates that pre-20th century vegetation at
the sites consisted of sawgrass marshes in a peat-accumulating environment; these assemblages
indicate moderate hydroperiods and water depths, comparable to those in modern sawgrass
marshes of Everglades National Park. During the 20th century, vegetation changed to grass-
dominated marl prairies, and calcitic sediments were deposited, indicating shortening of
hydroperiods and occurrence of extended dry periods at the site. These data suggest that the
presence of marl prairies at these sites is a 20th century phenomenon, resulting from hydrologic
changes associated with water management practices.
Introduction >
Related information:
SOFIA Project: Development and Stability of Everglades Tree Islands, Ridge and Slough, and Marl Prairies
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