Fall 2020 Resources and Publications

P-limitation drives changes in DOM production by aquatic bacteria
Thompson, S.K. and J.B. Cotner 
Aquatic Microbial Ecology   2020

Heterotrophic bacteria are key biogeochemical regulators in freshwater systems. Through both decomposition and production of organic matter, bacteria link multiple biogeochemical cycles together. 

Upper Midwest lakes are supersaturated with N2
Loeks, B.M. and J.B. Cotner 
Proceedings of the National Academy of Sciences of the United States of America  July 2020

Excess nitrogen (N) in freshwaters is problematic due to its impacts on eutrophication, biodiversity losses, and harmful algal blooms. Some microbial processes such as denitrification and anammox can remove N from systems while others such as N-fixation can add a usable form of N.

Combined use of radiocarbon and stable carbon isotopes for the source mixing model in a stream food web
Ishikawa, N. F.,   J. C. Finlay,  H. Uno,  N. O. Ogawa,  N. Ohkouchi,  I. Tayasu and  M. E. Power
Limnology and Oceanography  2020

Radiocarbon natural abundance has emerged as a useful dietary tracer in freshwater ecology for the past decade, yet its applicability for separating aquatic and terrestrial resources has not been examined quantitatively.

Regional prediction of nitrate‐N loads in subsurface drainage as a function of fertilizer application rate and timing in Southern Minnesota
Wilson, G.L.,  D.J. Mulla, J.A. Vetsch and  G.R. Sands 
Journal of Environmental Quality  July 2020

Fertilizer management practices which focus on applying nitrogen (N) fertilizer at the right rate and time have been proposed as a practical option to reduce nitrate‐N losses from subsurface drained agricultural fields. 

Characterization of Antibiotic Resistance and Metal Homeostasis Genes in Midwest USA Agricultural Sediments
Brooker, M.R., W.A. Arnold, J.F. Kerrigan, T.M. LaPara, J.D. Wiotter and P.J. Mouser
Water  September 2020

Microbial antibiotic resistance is a naturally occurring phenomenon that has grown in part with the use of antibiotics in agricultural operation. There are also known connections between genes for metal homeostasis and antibiotic resistance, and either antibiotics or metals may select for both kinds of genes.