Content area
Full Text
The ISME Journal (2015) 9, 13521364 & 2015 International Society for Microbial Ecology All rights reserved 1751-7362/15 http://www.nature.com/ismej
Web End =www.nature.com/ismej
ORIGINAL ARTICLE
A multitrophic model to quantify the effects of marine viruses on microbial food webs and ecosystem processes
Joshua S Weitz1,2, Charles A Stock3, Steven W Wilhelm4, Lydia Bourouiba5,Maureen L Coleman6, Alison Buchan4, Michael J Follows7, Jed A Fuhrman8, Luis F Jover2, Jay T Lennon9, Mathias Middelboe10, Derek L Sonderegger11, Curtis A Suttle12,Bradford P Taylor2, T Frede Thingstad13, William H Wilson14,16 and K Eric Wommack15
1School of Biology, Georgia Institute of Technology, Atlanta, GA, USA; 2School of Physics, Georgia Institute of Technology, Atlanta, GA, USA; 3Geophysical Fluid Dynamics Laboratory, NOAA, Princeton, NJ, USA;
4Department of Microbiology, University of Tennessee, Knoxville, TN, USA; 5Department of Applied Mathematics, Massachusetts Institute of Technology, Cambridge, MA, USA; 6Department of Geosciences, University of Chicago, Chicago, IL, USA; 7Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA; 8Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA; 9Department of Biology, Indiana University, Bloomington, IN, USA; 10Marine Biological Section, University of Copenhagen, Copenhagen, Denmark; 11Department of Mathematics, Northern Arizona University, Flagstaff, AZ, USA; 12Department of Earth and Ocean Sciences, Department of Botany, and Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada; 13Department of Biology, University of Bergen, Bergen, Norway; 14Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA and 15Delaware Biotechnology Institute, University of Delaware, Newark, DE, USA
Viral lysis of microbial hosts releases organic matter that can then be assimilated by nontargeted microorganisms. Quantitative estimates of virus-mediated recycling of carbon in marine waters, first established in the late 1990s, were originally extrapolated from marine host and virus densities, host carbon content and inferred viral lysis rates. Yet, these estimates did not explicitly incorporate the cascade of complex feedbacks associated with virus-mediated lysis. To evaluate the role of viruses in shaping community structure and ecosystem functioning, we extend dynamic multitrophic ecosystem models to include a virus component, specifically parameterized for processes taking place in the ocean euphotic zone. Crucially, we are able to solve this model analytically, facilitating evaluation of model behavior under many alternative parameterizations. Analyses reveal that the addition of a virus component promotes the emergence...