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Table 7. (Continued) Ecosystem, and other information Application rate and other variables Effects and reference. 30.5 m long X 3.6 m wide X 81 cm deep Shallow pond, mean depth 0.25 m, surface area 0.11 ha, high vegetation Shallow ponds Woodland pools Woodland pools days 41 to 100. Inter- mittent treatment stream received dosage 14X higher than continuous treatment stream, but dosage was confined to 24 hours every 14 days. Chlorpyrifos administered as emulsifiable concen- trate in petroleum de- rivative solvent Individual applications of 0.056 kg/ha, technical grade, 2 applications at 34-day interval 0.056 kg/ha, emulsifiable concentrate, oil diluent single application Single application of 0.056 kg/ha, granular formulation 0.056 kg/ha, granular formulation, single application 20 ever, in both treated streams, species diver- sity decreased by equal amounts and was still decreasing at day 100. Adverse sublethal effects were noted in fathead minnows, Pimeohales prome1as (spinal defor- mities) and bluegills (ChE inhibition, signs of organophosphorus poi- soning) only in the pulse-dosed stream. In all streams, however, fish survived, grew, and reproduced equally well (Eaton et a1. 1985). After 63 days, 46% to 55% mortality in centrarchid populations, and 75% re- duction in insect popula- tions of caddisflies, may- flies, and midges (Macek et al~ 1972). All caged green sunfish (Lepomis cvanel1us) died (Linn 1968). Increased algal growth on leaf litter observed months after treatment, attributed to reduction in grazing stress by mosquito larvae (Hagmann and Porteous 1972). Isopod populations re- duced 90% to 95% (Cooney and Pickard 1974).