Ephemeral aggregate layers in the water column leave lasting footprints in the carbon cycle

Abstract

Marine aggregates play a critical role in the biological pump, both as a dominant component of carbon flux and as hotspots for organic matter remineralization by microbial communities. In this study, we used laboratory experiments to investigate how aggregate thin layers, such as those commonly found in the coastal ocean, affect the distribution of bacteria and their activity. Diatom aggregates were added to a stratified water column, forming layers within which both microbial concentration and extracellular enzyme activity were substantially increased relative to background levels. Importantly, this enhancement of bacterial concentration and activity persisted long after the marine snow aggregates settled through the tank—that is, 10 times longer than the duration of the aggregate layer at the density interface. Thus, these small‐scale microbial interactions within aggregate layers leave behind considerable “carbon processing footprints” in the water column that may affect biogeochemical cycles at much larger temporal and spatial scales.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 03, 2017
Source ID
10.1002/lol2.10053

Entities

People

  • Brian L. White
  • Carol Arnosti
  • Jennifer C. Prairie
  • Kai Ziervogel
  • Richard M McLaughlin
  • Roberto Camassa
  • Zackary I. Johnson

Organizations

  • Duke University
  • National Science Foundation
  • Office of Naval Research
  • University of North Carolina at Chapel Hill
  • University of San Diego

Tags

Fields of Study

  • Biology
  • Environmental science

Readers

  • Marine Ecotoxicology
  • Mathematics or Statistics
  • Microbial Pathology

Technology Areas

  • Biotechnology
  • Biotechnology - Bioremediation