Baseline and monitoring methods for seagrass meadows

Seagrass meadows are one of the most vulnerable habitats of coastal or estuarine waters in Australia. Their continued existence near centres of human population is in peril, but all levels of government are now under pressure to protect these valuable habitats. The first step is to measure the health and abundance of the seagrasses. To help managers to do this, I describe some of the methods used successfully in Australia and overseas. Aerial surveys and remote sensing are discussed as the method for gross scale inventory gathering. Permanent transects can detect changes at a much smaller scale. Biomass, density and productivity measurements all indicate the ''health'' of seagrass meadows. These methods are described with emphasis on the need for statistical rigour and regard for temporal and spatial variability. If managers and researchers use the same or similar methods throughout the coastal and estuarine seagrass habitats, they can compare results and use baseline studies and findings from other areas, where relevant. (C) 1996 Academic Press Limited