Temporal Biomonitoring Using Wild Celery, Vallisneria americana

Abstract

This study was carried out to assess the effects of sediment type, local water column, source of plants, and duration of exposure between 1990 and 1994 upon growth, survivorship and reproduction of Vallisneria americana at two sites in the Huron-Erie corridor of the Great Lakes. The major objective was to determine whether year-to-year variations affect consistency of results using Vallisneria as a biomonitoring tool. Relative annual rankings of results from experimental treatments did not change over a 4-year period. However, most of the absolute measures of plant performance varied significantly between years. Effects on plant growth and development were associated primarily with exposure to water columns, and secondarily to sediments. Measures of plant density, rate of clonal growth, leaf length, number of leaves per m 2, and plant biomass per m 2 were unusually high in the first year compared with the subsequent 3 years, perhaps due to disturbance associated with set-up of the experiment. Leaf-to-root surface area ratios provided a simple, consistent, and reliable measure of environmental quality. Other measures of plant performance varied significantly from year-to-year and, therefore, are not advised for long-term comparisons. Results of this study indicate that Vallisneria can be an effective temporal biomonitor of environmental quality.