Figure 6.

Metagenomic evidence for increased microbial respiration during NO3− addition in field and laboratory experiments. (a) Log-fold differences in gene abundance between NO3− enriched and unenriched salt marsh surface sediments collected from the TIDE nutrient enrichment experiment. (b) Log-fold differences in gene abundance in FTRs between NO3− amended reactors and reactors receiving only seawater. Red points indicate genes that are significantly different between the two treatments. (c) Heat map indicating the 35 biggest differences between amended and unamended FTRs for genes involved in carbon metabolism. (d) Heat map indicating the 35 biggest differences between amended and unamended FTRs for genes involved in the nitrogen cycle. Source: The data used in panels (c) and (d) were adapted from Bulseco and colleagues (2020).