Research Grants/Fellowships/SBIR

Regulation of Structure and Function of Periphyton From the Florida Everglades, USA

EPA Grant Number: U916229
Title: Regulation of Structure and Function of Periphyton From the Florida Everglades, USA
Investigators: Iwaniec Sauterel, David M.
Institution: Florida International University
EPA Project Officer: Just, Theodore J.
Project Period: January 1, 2003 through January 1, 2005
Project Amount: $87,452
RFA: Minority Academic Institutions (MAI) Fellowships for Graduate Environmental Study (2003) RFA Text |  Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Academic Fellowships , Fellowship - Environmental Science

Description:

Objective:

The objective of this research project is to use closed physical models (sealed chemostats with periphyton and water) and growth simulation modeling (with fluxes and forcing functions calibrated from the physical models and long-term field data) to: (1) parameterize regulators of key processes controlling eriphyton energy flows, biomass, mat formation, mat breakup, and state change; (2) quantify carbon and nutrient uptake, storage, and loss by periphyton; and (3) investigate patterns of energy flows, biomass, information, and efficiency of periphyton at steady states, during mat formation, mat breakup, and system-state changes.

Approach:

Periphyton mat assemblages have been identified as an indicator of ecosystem health and as an important component of aquatic ecosystems. Periphyton often comprises more than 50 percent of the organic biomass in the Everglades and serves as an important base of the food web and provides habitat structure for higher consumers. Periphyton also dominates primary production and is an important regulator of water column oxygen dynamic and nutrient content in this freshwater oligotrophic ecosystem. Everglades' periphyton dynamics respond rapidly to small changes in water quality and environmental drivers. Autotrophic and heterotrophic components are tightly coupled within a mat matrix in periphyton; following nutrient enrichment the periphyton mat matrix breaks up, often resulting in a state change of the Everglade microbial system. Many unanswered questions remain regarding the regulation and organization of periphyton mat formation, mat breakup, and relationships between system states. Patterns and mechanisms behind how and why the mat formation, mat breakup, and state changes occur are unknown. I will use closed physical models (sealed chemostats with periphyton and water) and growth simulation modeling (with fluxes and forcing functions calibrated from the physical models and long-term field data) to parameterize regulators of key processes controlling eriphyton energy flows, biomass, mat formation, mat breakup, and state change. I also will quantify carbon and nutrient uptake, storage, and loss by periphyton. This study will investigate patterns of energy flows, biomass, information, and efficiency of periphyton at steady states, during mat formation, mat breakup, and system-state changes.

Supplemental Keywords:

fellowship, aquatic ecosystems, periphyton, Everglades, water quality, habitat structure, nutrient enrichment, closed physical models, growth simulation modeling.