Chapter

Microbial primary production and phototrophy

David L. Kirchman

in Processes in Microbial Ecology

Published in print February 2011 | ISBN: 9780199586936
Published online December 2013 | e-ISBN: 9780191774645 | DOI: https://dx.doi.org/10.1093/acprof:oso/9780199586936.003.0004
Microbial primary production and phototrophy

More Like This

Show all results sharing these subjects:

  • Animal Pathology and Diseases
  • Biochemistry

GO

Show Summary Details

Preview

This chapter focuses on the most important process in the biosphere – primary production – the turning of carbon dioxide into organic material by higher plants and algae. While higher plants dominate terrestrial ecosystems, photosynthetic microbes account for nearly all of primary production in the oceans. After reviewing basic physiology of photosynthesis, the chapter discusses approaches to measuring gross and net primary production, and how these processes affect fluxes of oxygen and carbon dioxide into and out of aquatic ecosystems. It then points out that terrestrial plants have high biomass but relatively low growth, while the opposite is the case for aquatic algae. In spite of these fundamental differences, each ends up contributing roughly 50 percent of total primary production in the biosphere. But primary production varies greatly with the seasons in temperate ecosystems, punctuated by the spring bloom, when the biomass of one algal type, diatoms, reaches a maximum. Other abundant algal types include coccolithophorids in the oceans and filamentous cyanobacteria in freshwaters. After the bloom, small algae take over and out-compete larger forms for limiting nutrients because of superior uptake kinetics. Abundant types of small algae include two coccoid cyanobacteria – Synechococcus and Prochlorococcus – the latter said to be the most abundant photoautotroph on the planet because of its large numbers in oligotrophic oceans. Other algae, often dinoflagellates, are toxic. Many algae also can graze on other microbes, probably to obtain limiting nitrogen or phosphorus. Still other microbes are mainly heterotrophic, but are capable of harvesting light energy.

Keywords: net community production; photosynthesis; biological pump; picoplankton; harmful algal blooms; proteorhodopsin; aerobic anoxygenic phototrophs; photoheterotrophs

Chapter.  12145 words.  Illustrated.

Subjects: Animal Pathology and Diseases ; Biochemistry

Full text: subscription required

How to subscribe Recommend to my Librarian

Buy this work at Oxford University Press »

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.