Abigail Leslie, Case Western Reserve University

Class Year:

2024

Mentor:

Lorie Staver, Ph.D.

Abstract:

Poplar Island is an island restoration site with wetland and upland habitats. The tidal marshes have a thick layer of edaphic algae present on the surface of areas without macrophytes. To increase our understanding of the role of edaphic algae in carbon cycling in the marshes, we measured algal production and respiration rates using two methods. We evaluated oxygen cycling under a range of light intensities and under flooded versus unflooded conditions. We collected a total of 23 sediment cores throughout June-July 2024. Twelve unflooded cores were subjected to light levels of 0, 120, 200, 300, and 350 µmol m^-2 s^-1 photosynthetically active radiation (PAR); in addition, six cores were incubated under flooded and unflooded experimental conditions. In all eighteen cores oxygen concentrations were measured to estimate rates of photosynthesis. We found that the rate of photosynthesis increased when PAR increased, and the mean rate of photosynthesis was not significantly different between flooded and unflooded cores. Higher amounts of chlorophyll a were not correlated with higher rates of photosynthesis. 

Location:

Horn Point Laboratory