The effects of prey profitability on a toxicity-dependent eco-physiological Daphnia model

Session: 15. - Environmental 'omics: New Tools for Aquatic Ecosystem Science and Management

Felicity Ni, University of Toronto Scarborough, [email protected]
Noreen Kelly, University of Toronto Scarborough, [email protected]
George Arhonditsis, University of Toronto Scarborough, [email protected]

Abstract

In contaminated aquatic ecosystems, studies have suggested remediation through the addition of biomass to reduce toxicity at higher trophic levels. This phenomenon, termed growth dilution, postulates a rapid growth reducing bioaccumulation and trophic transfer due to a greater than proportional increase in biomass to toxicity. Our previous work (Ni et al., 2017) has demonstrated the role of food quality in ameliorating mercury toxicity in a single-prey phytoplankton-Daphnia system. We present a continuation of our previous work with a metabolomics-inspired theoretical model and expand the scope of our work to multiple prey to examine the roles of toxicity and food quantity, in addition to food quality in maintaining healthy population dynamics. We demonstrate that in addition to rapid growth from high quality algal food, food abundance. The dilution effect from increasing food abundance was accentuated when Daphnia were offered higher quality food. Our results at the lower trophic levels have major implications for entire ecosystems through trophic cascades and the immense capacity bioaccumulation to higher trophic levels (i.e., fish and humans). We highlight an alternative to the popular contaminant management strategy in the maintenance of biotic populations.

1. Keyword
modeling

2. Keyword
zooplankton

3. Keyword
ecosystem health

4. Additional Keyword
mercury

5. Additional Keyword
nutrition

6. Additional Keyword
ecophysiology