Colin Jackson

Professor of Biology

• Faculty
• Instructor

• Email:

  cjackson@olemiss.edu

• Office Location:

  506 Shoemaker Hall

• Phone:

  662-915-7495

• Website:

  Jackson's Publications

Dr. Jackson is a microbial ecologist who studies microbial communities in natural environments and in plant and animal hosts.

Publications

Kubala, Megan & Hopper, Garrett & Sánchez González, Irene & Jackson, Colin & Atkinson, Carla. (2024)

Freshwater mussels enhance sediment nitrogen-removal potentials and alter bacterial communities via nutrient release and bioturbation

Freshwater Science. 10.1086/733241.

The stream benthic substrate is associated with ecosystem functioning and provides important habitat for a multitude of organisms from microbes to larger macrofauna. Microbially mediated biogeochemical transformations are critical ecological processes that occur within benthic sediments. Benthic macrofauna, such as freshwater mussels (Bivalvia: Unionoida), can influence these processes by chemically and physically altering the stream substrate, consequently altering redox conditions and the sediment microbial community. However, few studies have investigated the interactions between burrowing macrofauna, benthic nutrient fluxes, and the associated microbial communities in freshwater substrata. We used a mesocosm experiment to investigate how mussels physically (via bioturbation) and chemically (via excretion and egestion) influence sediment–water nutrient fluxes and sediment bacterial community composition. Because many microbially mediated N-transforming pathways can be stimulated by mussel-derived nutrient inputs (excreted NH₄⁺ or organic matter biodeposits) or altered by bioturbation, we predicted that mussels would enhance sediment N-removal potentials and alter the sediment microbial community structure, but that these effects would be mediated by mussel species identity and functional traits. Overall, the presence of mussels enhanced N-removal and modified sediment bacteria community composition and structure. The differences across mussel treatments in sediment N-removal potentials and alpha diversity of bacterial communities suggest that mussel species identity and assemblage composition play a critical role at the benthic–water-column interface in streams. Given the current declines in mussel species richness and abundance, a better understanding of the functional effects of mussel species and assemblage composition is critical to predicting changes in the functioning of stream ecosystems.