Sierra Nevada Aquatic Research Laboratory

24 Feb, 08 AM - 28 Feb, 01 AM

This proposed research focuses on the role of viruses in an alkaline, hypersaline environment: Mono Lake, California. Studies over the past decade have shown that viruses are generally the most abundant microorganisms in aquatic environments and that viral infections can be a significant source of mortality for planktonic bacteria and algae. Preliminary observation of water samples from Mono Lake, California indicates that viruses are on the order of 108-109/ml of water, among the highest ever observed in the aquatic environment. Viral infections can influence community structure, function, and biogeochemical cycling. Although the importance of viruses in typical marine and freshwater environments has been investigated over the past decade, almost nothing is known about their properties, ecology or their impact on foodwebs in alkaline hypersaline environments. Mono Lake has a relatively simple food web with very high phytoplankton production and brine shrimp as the sole macrozooplankton grazer. Pronounced physical and chemical gradients in Mono Lake resulting from meromixis also shape the structure of the microbial community over space and time. Therefore, it is an exceptionally attractive system for comparative studies of microbial ecological processes. In this proposed research, we seek to answer the following questions: How are viral abundance and dynamics in this unusual environment different from marine and freshwater environments? What is the contribution of viruses to their host mortality in this microbially dominated environment and how does this viral mortality rate compare with our current knowledge in other aquatic environments? How diverse is the viral community in this environment and how is community composition influenced by the permanent chemical stratification? How are the viruses here different from other known viruses in terms of both genetic and physiological properties? During the course of this study, we will collect samples for total viral counts, determine the frequency of infected cells investigate the viral diversity using both viral isolates and direct molecular approaches, and characterize indigenous viral-host systems. The proposed research integrates multidisciplinary approaches via close collaboration with the newly funded 5-year Mono Lake Microbial Observatory Study (MObs) led by Drs. Hollibaugh, Jellison, Joye and Zehr. Routine measurements of water level, meteorology, runoff, water column physical parameters, nutrients, H2S, methane, chlorophyll profiles, primary production, nitrogen fixation, particulate organic C and N, bacterial biomass, bacteria production, characterization of Bacterial and Archaeal community composition, DOC/DON profiles and zooplankton biomass, age structure etc., are being conducted as part of the MObs study. Our proposed research complements the MObs study and allows an integrated study of viral communities to be conducted with a reasonable research budget. The results of this study will provide new insights into the occurrence, diversity and function of microbiological life forms in a unique environment. Such a study contributes to our understanding of ecological organization under extreme conditions. This study also provides opportunities to educate graduate and undergraduate students in environmental biology research.

Visit #946 @Sierra Nevada Aquatic Research Laboratory

Approved

Under Project # 824 | Research

University of California Irvine - Environmental Analysis and Design

faculty - University of California, Irvine

Reservation Members(s)

Group of 2 Faculty Feb 24 - 28, 2003 (5 days)
Group of 2 Research Scientist/Post Doc Feb 24 - 28, 2003 (5 days)

Reserve Resources(s) | Create Invoice

Dorm 4 Feb 24 - 28, 2003
Lab 8 4 Feb 24 - 28, 2003