The Impact of Aqueous and Particulate Phosphorous on Cyanobacteria Associated with HABs

Session: 41a. - Great Lakes Harmful Algal Blooms Research from Watershed Influence to Ecosystem Effects

Elizabeth Crafton, University of Akron, [email protected]
Anny Gao, University of Akron, [email protected]
Don Ott, University of Akron , [email protected]
Teresa Cutright , University of Akron , [email protected]

Abstract

This study assessed the role of reactive phosphorus sources on three different cyanobacteria assemblages under storm simulated conditions, designed to mimic a storm-drive, pulse-input of nutrients and disruption of sediment in a coastal community.  The role of aqueous and particulate phosphorus was assessed independently and collectively.  The experimental design consisted of 10 phosphorus conditions, main factors effects as well as interaction.  The first cyanobacteria composition was 70% non-diazotrophic and 30% diazotrophic, the second was 13% non-diazotrophic and 87% diazotrophic, and the third composition was 29% non-diazotrophic and 71% diazotrophic.  The cyanobacteria were indigenous and were collected with a phytoplankton net, they were not placed in media.  Preliminary results suggest that both aqueous and particulate sources are relevant contributors.  The results highlight shifts in the cyanobacteria assemblage after simulated pulse-input.  The abiotic controls highlighted a rapid limitation of aqueous reactive phosphorus when soil was present, which may suggest a binding to sediment.  This binding and rapid limitation in the water column may trigger cyanobacteria’s ecophysiological characteristics.  Such as, luxury phosphorus uptake and storage as polyphosphate bodies, production of extracellular enzyme, phosphatase, and production of cyanophycin granules.  These experiments are on going, therefore, only minimal details can be provided at this time.

1. Keyword
coastal ecosystems

2. Keyword
cyanophyta

3. Keyword
phosphorus