Figure 5: Nutrient enrichment also enhances both autotrophy and heterotrophy.

High-tide only dissolved oxygen-based NEM in the fertilized (red) and reference (blue) tidal creeks (a) and the difference (black) between the fertilized and reference creeks (b) plotted against time of day for each of the 12 high tides during a 6-day period in August 2012. Each point represents the mean NEM or difference rates evaluated every 10 min over the hour of high tide, with one s.d. bar for the means. Note the mean difference rate over each hour of high tide is more tightly constrained than the mean for either creek. Shading denotes the period between dusk and dawn, and black arrows identify the time range of three tides that flood the high marsh platform and may have systematic positive biases in NEM, particularly in the reference creek (see Methods).