Patterns of microbial abundance and heterotrophic activity along nitrogen and salinity gradients in coastal wetlands Batanero Franco, Gema Laura Reche Cañabate, Isabel Coastal wetlands Heterotrophic prokaryotic abundance and production Cyanobacteria Viruses Salinity Nitrogen Funding for open access charge: Universidad de Granada/CBUA. This research was funded by the projects FLAMENCO (CGL2010-15812) and CRONOS (RTI2018-098849-B-I00) of the Spanish Ministry of Economy and Competitiveness and Ministry of Science and Innovation, the Modeling Nature Scientific Unit (UCE. PP2017.03), European Regional Development Fund (ERDF) and a PhD fellowship FPI (Formacion del Personal Investigador: BES2011-043658) to GLB. Coastal wetlands are valuable aquatic ecosystems with high biological productivity, which provide services such as a reduction in nitrogen loading into coastal waters and storage of organic carbon acting as carbon dioxide sinks. The predicted rise of sea level or freshwater extractions, particularly in the arid Mediterranean biome, will salinize many coastal wetlands. However, there is considerable uncertainty about how salinization will affect microbial communities and biogeochemical processes. We determined the abundance of total prokaryotes, cyanobacteria, and viruses and quantified the heterotrophic production of prokaryotes sensitive- (predominantly Bacteria) and resistant- (predominantly Archaea) to erythromycin in 112 ponds from nine coastal wetlands. We explored the main drivers of prokaryotic abundance and heterotrophic production using generalized linear models (GLMs). The best GLM, including all the wetlands, indicated that the concentration of total dissolved nitrogen (TDN) positively affected the total abundance of prokaryotes and the heterotrophic erythromycin-resistant (ery-R) production. In contrast, heterotrophic erythromycin-sensitive (ery-S) production was negatively related to TDN. This negative relationship appeared to be mediated by salinity and virus abundance. Heterotrophic ery-S production declined as salinity and virus abundance increased. Consequently, we observed a switch from heterotrophic ery-S production towards ery-R production as salinity and virus abundance increased. Our results imply that microbial activity will change from heterotrophic bacterial-dominated processes to archaeal-dominated processes with anthropogenic nitrogen and salinization increases. However, more studies are required to link the mineralization rates of dissolved nitrogen and organic carbon with specific archaeal taxa to enable more accurate predictions on future scenarios in coastal wetlands. 2022-04-04T11:32:42Z 2022-04-04T11:32:42Z 2022-03-17 info:eu-repo/semantics/article Batanero, G.L... [et al.]. Patterns of microbial abundance and heterotrophic activity along nitrogen and salinity gradients in coastal wetlands. Aquat Sci 84, 22 (2022). [https://doi.org/10.1007/s00027-022-00855-6] http://hdl.handle.net/10481/74091 10.1007/s00027-022-00855-6 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Springer