Bioconcentration in Cladophora Glomerata and Orconectes Propinquus: Following the Fate of Atrazine in the Little Miami River Watershed, Ohio
Atrazine is an herbicide applied to corn and a non-point source pollutant of agricultural watersheds. This study followed the fate of atrazine in the eutrophic Little Miami River watershed after runoff. Atrazine concentrations were followed in the mainstem of the Little Miami River (LMR) at 3 sites over a year sampling period, and for one sampling date at 11 tributary sites. Atrazine concentrations in the water ranged 0.29- 4.2 ?g/l over the course of the study. In the mainstem of the LMR atrazine was taken up by the filamentous algae Cladophora glomerata. The bioconcentration factor of C. glomerata ranged from 29-5223 during a one-year sampling period (n=13 for each of 3 sites), and bioconcentration was found to be a function of maximum biomass increase (due to high nutrients) and a negative function of discharge. Uptake increased at low discharges as a result of increased contact time between cells and water. C. glomerata was able to bioconcentrate a yearly average of 54% of the available atrazine from the water, based on several assumptions. The study of 11 tributaries revealed the possible bioaccumulation effects in herbivores using the Cladophora grazer, Orconectes propinquus. This study showed that crayfish bioconcentration is directly correlated to Cladophora atrazine bioconcentration. The crayfish body burden of atrazine was directly related to the presence of Cladophora at the site where the crayfish were found. There was a significant difference between the atrazine body burden at sites where the crayfish could ingest Cladophora and those sites with no Cladophora where the mode of uptake was either through dermal or gill contact, or ingestion of another food source. Biomagnification was also observed as the crayfish ingested atrazine via Cladophora consumption (Bioconcentration Factor ranged 460-6600). These studies show the importance of Cladophora as a major sink for aqueous atrazine and the potential risk to the organisms that consume Cladophora, thus passing atrazine along through the food chain.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:atrazine cladophora glomerata bioconcentration orconectes propinquus eutrophic river
Date of Publication:01/01/2002