POSTER SESSION 4
10:30–12:30, Thursday, September 17
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
ABSTRACT 1317 | POSTER 28
ESTIMATION OF COMMUNITY LEVEL PHYTOPLANKTON STRESS TO MICRO- AND MACRO-NUTRIENTS
Accurately quantifying ocean productivity requires moving beyond simple biomass metrics to understand the physiological state of phytoplankton. While chlorophyll-a concentration is a standard satellite product, it often fails to distinguish between biomass shifts and physiological acclimation to nutrient scarcity. This limitation introduces significant uncertainties into global estimates of Net Primary Production (NPP).
This study presents a novel method to estimate phytoplankton physiological stress related to macronutrient concentrations using satellite data which can also be adapted to discrete and continuous in-situ measurements. This method shows promising results to study the spatial distribution of macronutrient stress around islands in the tropical and subtropical Pacific Ocean and could be extended to global studies.
We also developed a method to estimate iron limitation from underway data by combining chlorophyll fluorescence data, chlorophyll concentration estimated from particulate absorption, and instantaneous photosynthetically available radiations. This method applied to available historical underway datasets, would expand the availability of in-situ estimates of micronutrient stress that are lacking for satellite algorithm development and validation.
Global estimates of micro- and macro-nutrient stress would advance our understanding of phytoplankton physiology, thereby refining methods to estimate NPP globally and improving predictions of future changes in marine ecosystems.
Guillaume Bourdin, University of Maine, [email protected], https://orcid.org/0000-0001-7608-5256
Emmanuel Boss, University of Maine, School of Marine Sciences, Orono, ME, USA, [email protected], https://orcid.org/0000-0002-8334-9595
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
