ARS | Publication request: Fry pond plankton and water quality: The impact of Propanil and Atrazine Drift

Submitted to: American Fisheries Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2006
Publication Date: September 14, 2006
Citation: Ludwig, G.M., Perschbacher, P. 2006. Fry pond plankton and water quality: The impact of Propanil and Atrazine Drift [abstract]. American Fisheries Society 136th Annual Meeting, September 10-14, 2006, Lake Placid, NY. 2006 CDROM No.68.

Technical Abstract: Aquaculture production ponds (averaging 7 ha are often adjacent to fields of row crops. Impacts of drift at up to 20 percent of field rates of 29 aerially applied herbicides on production pond plankton and water quality were evaluated in 500 L outdoor mesocosms over the span of 10 years. Propanil (rice), atrazine (corn) and diuron (cotton) produced negative impacts. Smaller fry ponds (1 ha) could receive higher drift levels. Ten water quality parameters were evaluated after the frequently-used herbicides propanil and Basis Gold (87 percent atrazine) were applied at 30 percent of field rates to pond water pumped into triplicate mesocosms after fertilization prior to fry stocking. No differences were noted preapplication. Significant (P less than 0.05, single tail t) impacts were noted in lower net primary productivity, morning DO and the minute cyanobacteria Chroococcus sp, however levels were not critical and no reduction in fry survival if stocked would be expected. Lower pH and consequently unionized ammonia and enhanced green algae and diatoms observed may be beneficial. Few differences were found in zooplankton and chlorophyll. Copepod nauplii were higher on day 4 and chlorophyll was higher on day 2 in the propanil treatment.