Effects of 2,4-dichlorophenoxyacetic acid on freshwater ponds : fungal propagules / J. Sherry. : En13-5/93-50E-PDF

"The effect of treatments with 2,4-dichlorophenoxyacetic acid (2,4-D) on fungal propagules in man-made freshwater ponds was studied as part of a larger investigation into the effects of the herbicide on the ponds' ecology and chemistry. Myriophyllum spicatum was planted in the ponds as a target plant; the ponds were allowed to stabilize before being treated with djmethylamine (DMA) and butoxyethylester (BEE) derivatives of 2,4-D (1 mg/L). The treatments did not have a clear effect on propagule levels in either the water column or sediment, which indicates the absence of a primary effect. The mean levels of moulds and "total fungi" in both sets of treated ponds, and of yeasts in the DMA treated ponds tended to be depressed relative to the control ponds over the first 114 days after treatment. That observation was reinforced by plots of the accumulated differences between the treated and control ponds. The mean differences between the control and treated ponds were highly variable, however. The degree of replication did not permit a statistical test of those differences. If real, the trends were probably a result of unidentified secondary effects of the pond treatments. The results imply that applications of 2,4-D to aquatic vegetation at realistic rates do not drastically affect fungi in the water column or sediment"--Abstract.

Lien permanent pour cette publication :
publications.gc.ca/pub?id=9.878538&sl=1

• Format MARC XML
• Format MARC HTML

Demander des formats alternatifs