Measuring the Standing Crop of Intertidal Seaweeds by Remote Sensing

Abstract

Data on the potential algal resources of the French intertidal zone are often sparse and discontinuous - when they exist. The economic interest in Ascophyllum nodosum and Fucus serratus for the extraction of alginates and as animal feed are among several reasons for making an inventory, especially since exploitation of these algae is easier than for Laminariales, which are almost always submerged. However, effective exploitation requires detailed knowledge of the existing crop and its fluctuations. Furthermore, some species might, in the future, prove to be useful in the pharmaceutical industry, but, taking seasonal variations into account, one must know both where to find them, as well as the best time for harvesting. As benthic algae continuously respond to and absorb the characteristics of the surrounding water, they can also be valuable bio-indicators of possible or existing pollution.