No abstract

Net primary production and species diversity were studied during the successional

Hypochlorite, permanganate, and peroxide with iron were compared for their effectiveness against adult zebra mussels (Dreissena polymorpha). The effects of hypochlorite and permanganate at applied concentrations of 0.5–2.5 mg/L were contrasted in continuous and intermittent 28‐day static renewal tests. In addition, 0.5–10 mg free Cl2/L, 0.5–2.5 mg KMnO4/L, and 1–5 mg H2O2/L (with iron at 25 percent of the H2O2) were applied continuously for 28 or 56 days in flow‐through systems. Permanganate was usually less effective than hypochlorite, and both were much more effective than the peroxide–iron combination. The data also indicated that intermittent treatments were ineffective (mussels avoided the chemical by closing up during treatments), that chlorine and permanganate were less toxic at lower temperatures, and that less chlorine was needed for a given kill when lower concentrations were applied.

Myxococcus fulvus BGO2, a cyanobacteriolytic bacterium, reduced densities of the cyanobacteria Nostoc muscorum and Phormidium luridum in six inorganic media and in filtered water from Lake Erie when inoculated to give initial myxococcal densities of 5 × 106 cells ml−1. When initial myxococcal densities were lower, the reduction in Nostoc density was delayed in a nutrient‐rich medium and did not occur in a nutrient‐poor medium. These laboratory results suggest that the absence of myxobacteria in cyanobacterial blooms and the absence of cyanobacterial population control by related lytic bacteria, found in natural blooms, may be due, in part, to insufficient inorganic nutrient fertility to support growth of lytic bacterial populations to densities necessary to cause significant cell lysis in host populations.