Marine Lab hosts UF researchers for algae study
In partnership with the Sanibel-Captiva Conservation Foundation’s Marine Lab, Patrick Saldana — a Ph.D. candidate at the University of Florida — is studying macroalgae decomposition and the effects on dissolved oxygen and nitrogen cycling in shallow environments, with a focus on Matlacha Pass.
Commonly referred to as seaweeds, macroalgae are a natural and common component of seagrass ecosystems, but recent algal blooms have smothered seagrass beds in the Charlotte Harbor, the SCCF reported. In addition to having negative consequences for seagrasses — an important habitat-forming species within the systems — the decomposition of macroalgae can also initiate hypoxic events when combined with local tidal circulation patterns.
Saldana’s advisor is Andrew Altieri, Ph.D., who has studied hypoxia and its effects on marine life in New England and Panama. Together, they will deploy oxygen sensors to monitor and quantify how dissolved oxygen levels are affected by recent macroalgae blooms.
Saldana has set up several manipulative experiments with several common macroalgal species to examine differences in algae decay rates, uptake and release of nitrogen, and he will work with UF biogeochemist Ashley Smyth, Ph.D., to collect core samples to study microbial transformations of biogeochemical processes in subtidal sediments as a result of algae decomposition.
Although macroalgae can smother seagrasses and cause immediate changes in habitat quality, their effects on sediment characteristics such as sulfide levels, oxygen flux and grain size may have long-lasting implications for seagrass recovery in the Charlotte Harbor.
Saldana hopes that his research will contribute to a broader understanding of seaweed ecology from a trait-based perspective and provide insight for the management and restoration of the Charlotte Harbor’s subtidal ecosystems following algal blooms.