Project: OCE-PRF Ecological consequences of seawater chemistry modification by ecosystem engineers

NSF Award Abstract
This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). This project will determine how ecosystem engineers shape communities by altering local chemistry. Ecosystem engineers modify the physical properties of a habitat often via the dense aggregation of individuals (e.g. mussel beds, kelp canopies, etc.) and can harbor extensive biodiversity compared to unmodified habitats. Such habitats can control resident communities through a variety of mechanisms including altering local chemistry. Through laboratory and field experiments, this project will compare how the altered chemical environments within diverse assemblages of habitat-forming species can shape long-and short-term community resilience to chemical stress. Results of this study will directly inform aquaculture, conservation, and restoration by revealing mechanisms available to prepare communities for more stressful oceans in the future. This project will additionally broaden participation in science by groups typically underrepresented in ecology by partnering with existing STEM recruitment programs and allocating funds to compensate participants. In collaboration with local shellfish aquaculture and community education programs, this project will also serve as the basis for education and outreach materials that are used to increase peoples’ connection to the environment while educating them on topics related to environmental stewardship and scientific research in an academia-industry-community collaboration.

Small scale alterations of seawater chemistry within biogenic habitats can be dominated by biological processes like respiration, photosynthesis, calcification, dissolution, and their combinations (e.g. macroalgal canopies vs coralline algal canopies vs mussel beds). Each of these processes has different consequences for the seawater carbonate system in that they can, for example, either decrease or increase carbon dioxide concentrations (photosynthesis and respiration, respectively) or either decrease or increase alkalinity (calcification and dissolution, respectively). These processes additionally occur against a backdrop of further perturbations to carbonate chemistry by larger scale processes like ocean acidification or riverine discharge. This project will examine the ability of different habitat-forming ecosystem engineers to ameliorate diverse chemical stresses within the habitat they create and the time scales over which that amelioration occurs.Short-term amelioration potential will be assessed by determining whether habitat preference of mobile or settling taxa differs under acute chemical stress conditions. By measuring growth rates of residents within diverse types of biogenic habitat this project will reveal amelioration potential during a resident organism’s lifetime. Lastly, the ability of these habitats to drive resident adaption to chemical stress will be determined by tracking how strains of a locally adapted clam originating from different types of habitats perform in the face of chemical stress events. Overall, this project, aims to reveal the chemical contexts under which various types of chemical modification by foundation species can either facilitate or inhibit the members of associated invertebrate communities across several time scales This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.