Project: Collaborative Research: Rhythm and Blooms: Deciphering metabolic, functional and taxonomic interactions over the life cycle of a phytoplankton bloom

OCE Award Pending summary:

Phytoplankton blooms, from initiation to decline, play vital roles in biogeochemical cycling by fueling primary production, influencing nutrient availability, impacting carbon sequestration in aquatic ecosystems, and supporting secondary production. In addition to environmental conditions, the physical and chemical interactions between community members can significantly modulate blooms, influencing the growth, maintenance, and senescence of phytoplankton. Recent work in steady-state open ocean ecosystems has shown that important chemicals are transferred amongst plankton on time-dependent metabolic schedules that are related to diel cycles. It is unknown how these metabolic schedules operate in dynamic coastal environments that experience perturbations, such as phytoplankton blooms. Here, we propose to address the following 3 questions; 1) What is the succession of metabolic activities over the course of an algal bloom and how is metabolic succession associated with ecological succession? 2) How are metabolic shifts in the community influenced by or influencing dissolved metabolite profiles through different bloom stages? and 3) Are there universal chemical or biological indicators that can be utilized as predictive markers of phytoplankton bloom phases during other natural ecosystem events?

We will address these questions using samples we collected in 2021 from coastal waters in East Sound, WA every 4 hours for 22 days, capturing a phytoplankton bloom from initiation to decline and in 2022, from samples collected using identical time intervals for 32 days at the same location. Microbial eukaryotes, bacteria, and dissolved metabolites were collected for metatranscriptomics, metaproteomics, metagenomics, and metabolomics analyses. Time-matched environmental data will provide context for the biological and chemical signals we will interrogate here.

Phytoplankton blooms are generally sampled on time intervals of days to weeks, allowing researchers to capture changes that occur on time scales of 24 hrs or longer.  Recent research has revealed that important chemical handoffs occur amongst organisms on much shorter time intervals. Our proposed analyses of long-term, diel sample sets will reveal how chemical and biological signals associated with the initiation, maintenance, and cessation of phytoplankton blooms are modulated on both short (hrs) and long (days-weeks) time scales. Our findings will advance the ability to predict and manage phytoplankton dynamics, providing crucial insights into ecological stability and future oceanographic sampling strategies. Additionally, outcomes of this study will provide a new foundational understanding of the succession of microbial communities and their chemical interactions across a range of timescales. In the long term, this research has the potential to identify predictors that can help mitigate harmful algal blooms, optimize fisheries management, and guide future research on carbon sequestration.

Funding award numbers not yet known (OCE-xxxxxxx)