*********** +++++++++++++++++++++ 071995B.BIO + Source: ONR Asia + *********** +++++++++++++++++++++ Contributory Categories: ENV Country: South Africa From: Marine Sciences and Technology in South Africa Foundation for Research Development 1990 KEYWORDS: South Africa; Biological Oceanography, Marine Biology, +++++ MARINE SCIENCE AND TECHNOLOGY IN SOUTH AFRICA Part VIII/XXV MAJOR TOPICS (Continued) 1 Item SEAWEEDS Dr R J Anderson, Sea Fisheries Research Institute, Cape Town South African seaweeds have been relatively little studied. In the 1800s and earlier this century, local collectors sent specimens to experts in Europe, who described and named many species. This basic taxonomic work has been continued in South Africa since the 1930s, during which period ecological surveys have also provided basic descriptions of the distributions of the dominant intertidal seaweeds. At present, taxonomic knowledge of South African seaweeds is far from complete, and we know little of their ecology and almost nothing of their physiology. In particular, subtidal seaweeds, which have only become easily accessible to marine scientists with the widespread use of SCUBA in the last twenty years, are poorly known. In many areas of the northern hemisphere, fundamental taxonomic research on seaweeds (names and descriptions) was well advanced by the middle of this century, so that work can now focus on interactions between species and their environment. A recent list of the names of southern African seaweeds runs to some 550 species, but subsequent detailed taxonomic work in Natal has revealed more than 400 species of red algae alone in that area. It is clear that in South Africa we still need a rapid completion of basic taxonomic studies to provide a basis for and stimulate work which has begun in other fields such as biogeography and ecology. Commercial interest in seaweeds in South Africa has increased greatly since the 1950s, and at present kelp (large brown seaweed) in the westem Cape is collected from beach cast and exported for the extraction of alginate, which is used in the food and other industries. A limited amount of kelp is harvested for the preparation of a plant growth stimulant for agriculture and horticulture. In addition, agar, a gelling substance used in food and medical products, is obtained from several species of red seaweeds, chiefly from Gracilaria at Saldanha Bay and from Gelidium in the eastern Cape. Seaweed research in South Africa is carried out at various universities, and often funded partly or completely by the CSIR, while monitoring of commercially exploited populations is chiefly the responsibility of the Sea Fisheries Research Institute of the Department of Environment Affairs. At present, commercial activities are carefully controlled, and research has shown them to have little effect on the natural communities. There is, however, a good future for commercial use of many other South African seaweeds, such as those producing car-rageenan, a gelling substance similar to agar and also of use in food and other industries. Although local carrageenan-producing seaweeds are not currently exploited, research on several of these species has begun, recognizing that increasing human pressures on natural resources require a knowledge of the ecology, physiology and biochemistry of our sea. +++++ End Part VIII/XXV ***** CMR Disclaimer================================================== This document could contain information all or part of which is or may be copyrighted in a number of countries. Therefore, commercial copying and/or further dissemination of this text is expressly prohibited without obtaining the permission of the copyright owner(s) except in the United States and other countries for certain personal and educational uses as prescribed by the "fair copy" provisions of that countries Copyright Statues. ================================================================ ************** END Msg. B.BIO **************