Populations of Plankton Animals and Residual Chlorinated Hydrocarbons in Soils of Six Minnesota Ponds Treated for Control of Mosquito Larvae
- 1 July 1963
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 92 (3) , 211-215
- https://doi.org/10.1577/1548-8659(1963)92[211:popaar]2.0.co;2
Abstract
Short‐term effects of DDT upon summer populations of plankton animals in some Minnesota ponds are reported. DDT in bentonite and vermiculite granules was applied to three ponds in amounts used routinely for mosquito control: 1 pound per acre in early spring, and lesser amounts later as needed. By such application the nearly insoluble DDT is distributed in a thin layer on the pond bottom. Three similar ponds which were not treated with DDT during the 11‐week study period served as controls. However, all six ponds had been treated with DDT in one or both of the two preceding years. Averages of counts of cladocerans, copepods, ostracods, rotifers, and Volvox were of the same general magnitude for treated and control ponds. The crustacean counts from these ponds were similar to those reported from ponds in the St. Paul area investigated prior to the mosquito control program. A few days after treatment, however, there was indication of a depression of microcrustacean populations followed by apparent rapid recovery. Analyses of soils from the weedy margins of study ponds showed DDT concentrations ranging from 1.5 to 25.5 p.p.m. There were also small amounts of DDD and DDE in several of the soils. Heptachlor epoxide, which had not been used in the mosquito control program, was also found in soils from two of the ponds.This publication has 0 references indexed in Scilit: