The effects of light level and temperature on freshwater microbial biomass, production, enzyme activity, and community composition

<p>Algae can stimulate the production of heterotrophic microbes in periphyton communities, but the synergistic effects of light and temperature on this phenomenon are not well understood and have implications on carbon cycling and energy flow. We employed recirculating mesocosms held at different temperatures and light levels and filled with Typha litter and attached microbes to assess these effects. Heterotrophic microbial production was greater in the presence of light, as were some periphytic enzyme activities. Few response variables increased in a near-linear fashion with ascending temperature, suggesting different temperature optima. The strength of heterotrophic microbial production responses to algal photosynthesis did not vary with respect to temperature, but some enzyme activities did. The magnitude of light stimulation of bacterial production and several enzymatic activities were positively correlated, suggesting a similar driving mechanism. These findings advance our limited understanding of the synergistic effects of light and temperature on microbial communities.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Open Access Thesis

Discipline thesis:degree_discipline

Biology

Year dc:date.available

2020

Author dc:creator

• Bonney, Joel

Contributors dc:contributor

• Steven Francoeur, PhD
• Kristin Judd, PhD
• Daniel Clemans, PhD

• Algae
• Enzyme Activity
• Light
• Microbial production
• Priming Effect
• Temperature
• Aquaculture and Fisheries
• Biology
• Ecology and Evolutionary Biology

Repository record dc:identifier

https://commons.emich.edu/theses/1024

OAI identifier oai:identifier

oai:commons.emich.edu:theses-2389