MARINE BIOGEOGRAPHY, CLIMATE-CHANGE AND SOCIETAL NEEDS

Pelagic biogeography deals with the large scale distributional pattern s of pelagic organisms in the world's oceans, their origins through ev olution and the changes in ocean morphology during the geological past , and the factors which currently control and maintain them. The knowl edge it generates has a wide variety of uses in science, both basic an d applied, and in socio-economics. Its products include: (1) Distribut ional data compiled in data bases, maps and atlases; (2) Explanatory s cientific and non-scientific publications on the distributions and the ir implications; (3) Standardisation of methodologies; (4) Trained spe cialists; (5) Advice to society on oceanic aspects of global resource management; and (6) Assessments of oceanic biodiversity in relation to the Biodiversity Convention. The immediate users of this knowledge in clude oceanographers in other disciplines, ecologists, applied scienti sts and engineers, resource managers, fishermen, environmentalists, te achers, international lawyers and policy-makers. At present the larges t users are the natural resource managers seeking to optimise and to s ustain the resource for which they are responsible. There is a conside rable body of national and international legislation which is underpin ned by biogeographical information. Similarly much of our understandin g about past climate which is being used to predict future trends, is based on applying information on present-day distributional patterns t o the interpretation of the fossil record in marine sediments. Global change, in the ocean, the atmosphere and on land, is strongly modulate d by the feedback between marine organisms, nutrients and greenhouse g ases, The marked coherence observed between the distributions of physi cal, chemical and biological patterns suggest that the processes invol ved in this feedback are linked with pelagic community structure. Remo te sensing of sea-surface properties and the heat content of the mixed -layer, offer considerable potential for linking ecological and biogeo graphical processes to large scale features of ocean circulation and c limatology. The long-term monitoring of the ocean in the Global Ocean Observing System will need to integrate physical, chemical and ecologi cal data, if the models used to predict future change are to achieve a dequate precision. The future use and resource management of the ocean s has to involve biogeographical information. Traditional sampling met hods, even when supplemented by large scale surveys such as CALCOFI an d the Continuous Plankton Recorder surveys,will never provide sufficie nt data, so new techniques for intensive sampling and monitoring are b eing sought. Some surrogate measures such as chlorophyll fluorescence are already well established as standard oceanographic methodology; ot hers involving acoustics and optical properties have the potential for sampling the biological characteristics at the same time/space scales as the physicochemical properties of the oceans are being studied. Ho wever, the calibration of these new techniques against traditional sam pling and observational methods remains problematic. Information techn ology is beginning to be used, not only to unify the systematics of ma ny taxonomic groups, but also to improve information exchange. Improve ments in digital data bases will lead to freer exchange of information , and also facilitate the production of maps and interpretations custo mized for other users. The scientific resources being devoted to pelag ic biogeography are declining with potentially serious consequences. T his trend can only be reversed if the biogeographers themselves make t heir output more accessible and user-friendly for non-scientists, and take advantage of the new technologies which promise to re-vitalise th e field.