Using a retention pond to capture agricultural contaminants from surface waters

Maëva Marimoutou; Nicolas Gruyer; Roxanne Maranger; Georges Thériault; Isabelle Laurion

doi:10.1016/j.scitotenv.2023.166226

Using a retention pond to capture agricultural contaminants from surface waters

Sci Total Environ. 2023 Dec 10:903:166226. doi: 10.1016/j.scitotenv.2023.166226. Epub 2023 Aug 11.

Authors

Maëva Marimoutou¹, Nicolas Gruyer², Roxanne Maranger³, Georges Thériault⁴, Isabelle Laurion⁵

Affiliations

¹ Institut national de la recherche scientifique, Centre Eau Terre Environnement, Québec, QC, Canada; Centre d'expertise en analyse environnementale du Québec, Ministère de l'Environnement et de la Lutte contre les changements climatiques, Québec, QC, Canada; Interuniversity Research Group in Limnology (GRIL), Université de Montréal, Montréal, QC, Canada. Electronic address: maeva.marimoutou@univ-pau.fr.
² Centre d'expertise en analyse environnementale du Québec, Ministère de l'Environnement et de la Lutte contre les changements climatiques, Québec, QC, Canada; Biodôme, Espace pour la vie, Montréal, QC, Canada.
³ Interuniversity Research Group in Limnology (GRIL), Université de Montréal, Montréal, QC, Canada; Département des sciences biologiques, Université de Montréal, Montréal, QC, Canada.
⁴ Agriculture et agroalimentaire Canada, Gouvernement du Canada, Québec, QC, Canada.
⁵ Institut national de la recherche scientifique, Centre Eau Terre Environnement, Québec, QC, Canada; Interuniversity Research Group in Limnology (GRIL), Université de Montréal, Montréal, QC, Canada. Electronic address: isabelle.laurion@inrs.ca.

PMID: 37572900
DOI: 10.1016/j.scitotenv.2023.166226

Abstract

To meet the demand of a constantly growing population, agriculture is intensifying, causing an increased use of fertilizers and pesticides. Excessive nutrients transfer to aquatic ecosystems can disrupt the water quality and impact the aquatic life. Pesticides can also have toxic effects on non-target organisms from aquatic systems. The purpose of this study was to evaluate the efficiency of an agricultural retention pond in reducing the supply of nutrients, pesticides and suspended solids to the Nicolet River, a tributary of Lake St. Pierre in the St. Lawrence River. Research combining the study of the fate of a wide range of contaminants in both pond water and sediments, their toxicity to microcrustaceans, microalgae and amphipods, and the effectiveness of contaminant removal, has rarely been carried out in the past. Peak contaminant concentrations occurred one to two months after pesticide and fertilizer applications, and during the months with the highest rainfall. Toxic effects were only observed on microalgae, with suspended solids apparently responsible for this effect through light inhibition on growth rates. However, the pond was not effective in removing this toxicity even if suspended solids were largely removed. Pesticides removal varied widely among sampling dates and pesticide types, with an efficiency reaching 95 % for thiamethoxam, but generally remaining low and often negative (higher concentrations in outflowing water) for other pesticides. On the other hand, the mean fractional removal of suspended solids, phosphorus, and nitrogen based on concentrations was 71 %, 44 % and 22 %, respectively. These are conservative estimations since the removal rates based on loads were above 94 %. The use of retention ponds thus seems an efficient approach to reduce the quantity of fertilizers in rivers draining agriculture areas, but the studied pond was not systematically effective in removing pesticides.

Keywords: Agricultural contaminants; Nutrients; Pesticides; Retention ponds; Surface water; Toxicity.