Document Type
Thesis
Abstract
The Everglades of South Florida has a well-documented history of water management over the last century. Prior to 1900, the Everglades region was primarily influenced by seasonal precipitation cycles and topography. During the early 20th century, and again in the 1950s-60s, human development via canals, railroads, and levees greatly altered the freshwater regime of this area. Previous studies have sought a deeper understanding of preanthropogenic Everglades water quality in order to create modern targets under the Comprehensive Everglades Restoration Plan (CERP). The transitional zone of northeastern Florida Bay is slightly more complex than the southern and central portions of the bay. Salinity of the northeastern region of Florida Bay is impacted more by freshwater hydrology than by other factors such as tides, wind patterns, local precipitation and evaporation, and storm events. As a result, this area displays water quality changes more directly related to human influence. To gain further insight into the paleoecological history of the northeastern region of Florida Bay, we used the molluscan record and cumulative weighted percent analysis (CWP) to reconstruct salinity parameters for a piston core collected in February 1995 from Trout Creek, located in the transitional zone (N 25.20910, W 80.53320). From the 74-cm long core, I analyzed 10 evenly spaced 2-cm samples and identified and counted over 35 species of mollusk. Based on molluscan paleo-assemblages, the modern analog dataset, and 14C and δ18O isotope data from the bivalve Anomalocardia cuneimeris, | reconstructed salinity estimates and freshwater influx over time for Trout Creek. The resulting data were compared to molluscan CWP-derived salinity data from nearby Taylor Creek. Holmes et al. (2001) provided the additional 210Pb dating for Trout Creek Core used in this analysis. Salinity near Trout Creek and northeastern Florida Bay has fluctuated since ~388 AD and increased since 1900 AD, likely a result of the human alteration of freshwater regime around that time. Freshwater influx similarly fluctuated since ~388 AD, then decreased after 1900 AD. These patterns are similar in nearby Taylor Creek core though overall salinity is lower there. This study complements the work of many researchers under the CERP and provides new insight into the complicated freshwater system of the northeastern portion of Florida Bay.
Date Awarded
2016
Department
Geology
Advisor 1
Rowan Lockwood
Recommended Citation
McCluskey, Allison, "Paleoecology of northeast Florida Bay, Everglades National Park, Florida: Reconstruction of Salinity and Hydrology for the past ∼2000 years" (2016). Geology Senior Theses. William & Mary. Paper 371.
https://scholarworks.wm.edu/geologyseniors/371
