Grantee Research Project Results
2000 Progress Report: Foraminifera as Ecosystem Indicators: Phase 1. A Marine Benthic Perturbation Index; Phase 2. Bioassay Protocols
EPA Grant Number: R825869Title: Foraminifera as Ecosystem Indicators: Phase 1. A Marine Benthic Perturbation Index; Phase 2. Bioassay Protocols
Investigators: Muller, Pamela Hallock
Institution: University of South Florida
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1997 through September 30, 2002
Project Period Covered by this Report: October 1, 1999 through September 30, 2000
Project Amount: $295,043
RFA: Ecosystem Indicators (1997) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Aquatic Ecosystems
Objective:
Foraminifera are by far the most useful group of paleoenvironmental indicators utilized by geoscientists because: (1) their shells are important sediment constituents; (2) they are small and widely abundant; (3) different taxa have evolved to exploit most environments, substrates and nutritional modes in marine systems; and (4) their shells morphologically and geochemically record environmental conditions. This project is developing techniques and protocols for routine use of foraminifera as indicators of biological integrity in both field and laboratory settings. In Phase 1, we are testing an index for assessing perturbations of marine benthic ecosystems, which is based on changes in key taxa of foraminifera, and developing a "user's manual" to facilitate routine application of foraminifera in environmental monitoring projects. In Phase 2, we are developing bioassay protocols for foraminifera in field and laboratory studies of the effects of key stressors in marine benthic environments.
Progress Summary:
Phase 1. We have developed an index to quantify change in benthic ecosystems, which can be applied to historical, sediment-core, and surface-sediment data sets. The procedure requires minimal technology and can be applied by technicians with modest training. The model ranks relative abundances of key foraminiferal taxa and morphogroups, and total abundances, generating an index value when foraminiferal assemblages are compared temporally or spatially. The model can be adapted to local and regional biotas and can incorporate other environmental or taxonomic data that can be scaled to the model. We are field testing the index using published data, as well as surface samples and sediment cores from the Florida reef tract, Glover's Reef, Belize, and Tampa Bay, Florida. A key advantage of foraminifera as ecosystem indicators is that foraminiferal assemblages are preserved in the sediments, and that record often can be accessed by collecting and analyzing sediment cores. To field test the utility of the foraminiferal record in detecting recent change in reef sediments, short sediment cores were collected from locations in the upper, middle, and lower Keys. However, data from these cores indicate that sediment mixing by bioturbation and storms is too intense to yield a useful record in open shelf sediments, demonstrating the need to target core samples in more energy-restricted environments such as Florida Bay. Sediment cores from Hillsborough Bay clearly demonstrate anthropogenic influence in two of three ways: homogenization, introduction of planktonic foraminifera through bilge pumping, and total domination of relatively undisturbed samples by opportunistic Ammonia spp.
Phase 2. Amphistegina spp. are the most common reef-dwelling foraminifera with algal endosymbionts worldwide. Globally important in their own right, these foraminifera provide a model "calcifying symbiosis" for testing stressors that threaten the ecological integrity of coral-reef ecosystems. Known stressors include temperature stress, salinity change, and modest increases in ultraviolet-B (UV-B) radiation. Protocols have been adapted for measuring ATP as a means to determine viability and metabolic activities in A. gibbosa individuals. Specimens from the same field collections and laboratory experiments also have been analyzed cytologically to quantify numbers of symbionts, digestion of symbionts, proportions and kinds of vacuoles, and presence or absence of organelles. We have verified experimentally that exposure to elevated intensities of photosynthetically active radiation (PAR=400-70 nm), either alone or in combination with added UV-B (280-320 nm), induces symbiont loss in Amphistegina gibbosa similar to what has been seen in field populations, and that shorter wavelengths of PAR induce more bleaching than longer wavelengths.
Future Activities:
The goals for the final year of Phase 1 of this project are to complete one dissertation and two Master's theses, submit two to three papers for publication, and develop a "user's manual" to facilitate routine application of foraminifera to environmental monitoring. Phase 2. Goals for the final year of Phase 2 of this project are to complete two dissertations and submit at least three manuscripts for publication, one on ATP analysis, one on cytological effects of bleaching, and one on population responses to irradiance stress.
Journal Articles on this Report : 4 Displayed | Download in RIS Format
Other project views: | All 62 publications | 14 publications in selected types | All 10 journal articles |
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Fujita K, Hallock P. A comparison of phytal substrate preferences of Archaias angulatus and Sorites orbiculus in mixed macroalgal-seagrass beds in Florida Bay. Journal of Foraminiferal Research 1999;29(2):143-151. |
R825869 (1999) R825869 (2000) R825869 (2001) R825869 (Final) |
Exit Exit |
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Hallock P. Symbiont-bearing foraminifera: harbingers of global change. Micropaleontology 2000;46(Suppl 1):95-104. |
R825869 (1999) R825869 (2000) R825869 (2001) R825869 (Final) |
Exit Exit |
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Holzmann M, Hohenegger J, Hallock P, Piller WE, Pawlowski J. Molecular phylogeny of large miliolid foraminifera (Soritacea Ehrenberg 1839). Marine Micropaleontology 2001;43(1-2):57-74. |
R825869 (2000) R825869 (2001) R825869 (Final) |
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Pawlowski J, Holzmann M, Fahrni JF, Hallock P. Molecular identification of algal endosymbionts in large miliolid foraminifera: 1. Chlorophytes. Journal of Eukaryotic Microbiology 2001;48(3):362-367. |
R825869 (2000) R825869 (2001) R825869 (Final) |
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Supplemental Keywords:
coral reefs, Florida Keys, ATP analysis, IBI, cytology, RFA, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Ecology, Hydrology, Ecosystem/Assessment/Indicators, Ecosystem Protection, exploratory research environmental biology, Environmental Chemistry, Ecological Effects - Environmental Exposure & Risk, Ecological Indicators, ecological exposure, anthropogenic stresses, foraminifera, marine ecosystem, algae, coral reefs, stressors, benthic biota, ecosystem indicators, soil, aquatic ecosystemsRelevant Websites:
http://www.marine.usf.edu/reefslab
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.