Community Metabolism of Microbialite Oncoids in Laguna Bacalar, Mexico

Session: Poster session

Haley Lucas, School of Freshwater Science, hllucas@uwm.edu
Leah Holloway, University of Wisconsin-Milwaukee School of Freshwater Sciences, hollow43@uwm.edu
Leah Stromberg, UWM-freshwater science/ Alverno College, strombld@alverno.edu
Kaleena Jones, School of Freshwater Science / Alverno College, joneskm@alverno.edu
Ruth Fenelon, University of Milwaukee Wisconsin , fenelonr@uwm.edu
Jerry Kaster, University of Wisconsin-Mil, jlk@uwm.edu

Abstract

Laguna Bacalar, the second-largest freshwater lake in Mexico, is home to giant living thrombolytic microbialites, possibly the largest sized living freshwater microbialites. Included in microbialite formations are the smaller, thrombolytic oncoids found primarily in tributaries of the Laguna. Cenozoic limestone karst in the lagoon supports carbonate precipitation by cyanobacteria along with trapping and binding of mineral and detrital grains. Low-energy water movements resulted in a oncoid cauliflower morphology versus a smoother rounded shape. The oncoids were observed for their surface morphology, the structure and composition of the cortex, and the internal living phytoplankton and microzoan community. Components of the microbial community include testacid amoebae, nematodes, diatoms and filamentous algae. We tested for primary productivity/respiration of the oncoid community using light/dark chambers experiment housing individual oncoids. 

1. Keyword
diatoms

2. Keyword
species diversity

3. Keyword
metabolism

4. Additional Keyword
Mexico

5. Additional Keyword
oncoid

6. Additional Keyword
stromatolite