Quantitative grab sampler for dense beds of aquatic macrophytes

Abstract

The construction and operation of a simple mechanical grab, suitable for sampling dense beds of aquatic macrophytes, is described. The technique has several advantages over the diver‐quadrat method. Both methods have been used in vegetation surveys of the Rotorua lakes where plant densities attain the maximum recorded for freshwater lakes. The results indicate marked variations in weed density over short distances, and thus both methods require a large number of samples for an accurate determination of biomass. © 1976 Taylor & Francis Ltd.