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In the past, storm cast* seaweed was gathered on foot and without mechanization or any equipment. Since the beginning of the 17th century, the commercial use of seaweed, for commercial purposes, such as in the production of glass, encouraged local populations to regulate the activity by establishing rules. For example in France, the first national text, regulating seaweed harvesting, is an ordinance of 1681 which fixed the harvesting seasons of kelp and the number of authorized harvesting days. The use of seaweed for iodine production and later for alginate prompted improvements in harvesting techniques, in order to meet the increasing industrial demand industry for the raw material. Equipment to cut seaweed and boats to carry the algae ashore were first used early in the twentieth century. In 1970, harvesting of Laminaria digitata and Laminaria hyperborea was mechanized in France and Norway. In Europe, the main exploited algae species are Laminaria hyperborea, Laminaria digitata and Ascophyllum nodosum. These species, and especially kelp forests, are considered among the most ecologically dynamic and biologically diverse habitats on the planet. Other species are found on the European Atlantic coast but few of them currently have a commercial value. European scientists have mainly focused their research mainly on kelp which is considered a Keystone Species and whose presence affects the survival and abundance of many other species in the ecosystem. Nowadays, the preservation of kelp forests is placed at the center of environmental concerns and some countries have decided to protect these habitats by restricting the use of mechanical harvesting or by creating protected areas around them. Within this context, mechanical kelp harvesting and seaweed gathering by foot, generate much discussion between scientists, fishers, processing industries and environmental non-gouvernemental organisations. Kelp harvesting is blamed for harming the ecosystem because of the damage it can cause to substrates and to the habitats of certain fish. For some scientists the removal of the kelp species provokes negative effects on the invertebrate species that live in the holdfast, the stipe or fronds or under the fronds. In countries where Laminaria spp is harvested with mechanical equipment, scientists appear to be concerned with the equipment’s impact on the species and also on the surrounding ecosystem. This document presents the main characteristics of the seaweed industry in Europe, illustrated by examples from six European countries (Norway, France, Ireland, Spain, United Kingdom and Portugal). The aim is to have an overview of the European seaweed industry from the six baseline reports prepared by the partners of this project, from literature sources and information gathered during semi-structured interviews of different stakeholders. This document briefly presents the history of seaweed harvesting activity in Europe, the current production and the techniques used in the different countries. The different regulatory systems for the resource and coastal access are detailed followed by the management of the resource and finally the management of the human beings focusing on the social dimension of the activity. The diverse uses of the seaweed resource are outlined.

*material deposited on the shore after storms

This manual is designed for farmers, buying agents, exporters and fisheries officers who play an important role in achieving the required quality of seaweed for export. The purpose of the manual is to educate farmers to understand the importance of good-quality seaweed, the role they play and the benefits they can achieve. The manual also provides guidance for buying agents, exporters and fisheries officers in the roles they perform to improve and maintain the required quality of seaweed.

The deepwater seaweed resources survey was carried out during 1986-1991 at the depths ranging from 5 to 22 m in Tamilnadu coast from Dhanushkodi to Kanyakumari. The vegetation of seaweeds and sea grasses occurred in all areas except Dhanushkodi - Mandapam and Manapad – Kanyakumari. A total number of 100 algae and 5 seagrasses were recorded. Among the 100 algal species recorded, 20 species belonged to Chlorophyta, 18 species to Phaeophyta, 61 species to Rhodophyta and 1 species to Cyanophyta. The total estimated standing crop (wet wt.) from 1863 sq. km. sampled area was 75374.5 tonnes consisting of 2750 tonnes of Sargassum spp., 962.5 tonnes of Gracilaria spp., 5262.5 tonnes of Hypnea spp. and 66399.5 tonnes of other seaweeds. The quantitative analysis of economically important seaweeds revealed the feasibility of commercial exploitation of Sargassum from Mandapam to Kilakkarai and Tuticorin areas, Hyphnea from Mandapam to Vembar area and Gracilaria from Vembar to Nallatanni Tivu region. Hydrological data were, also collected from the area surveyed.

Survey of the deep water area from Kilakkarai (Appa Tivu to Rameswaram Island (Dhanushkodi) was undertaken from December 1990 to January 1991 in the IV Sector survey of Deep water Seaweed Resources off Tamil Nadu coast, which formed the last phase of the survey from Rameswaram to Kanyakumari carried out during 1986-91. An area of 417.5 sq.km. was surveyed yielding a total biomass of 18,162.5 tons (wet) seaweeds. Out of 167 stations surveyed in 13 transects, vegetation occurred only in 12 stations. Of the 29 species of marine algae recorded 8 belonged to Chlorophyta, 8 to Phaeophyta, 12 to Rhodophyta, and I to Cyanophyta, One species of seagrass Cymodocea serrulata was also recorded. Twenty species were found in estimable quantities, of which the following 8 species were abundant: Halimeda macroloba, Spatoglossum asperum, Zonaria crenata, Sargassum ilicijolium, Amphiroa fragilissima, Hypnea musciformis, Botryocladia leptopoda and Lyngbya majuscula with a biomass of 1325, 9775, 650, 1550, 1925,300,862.5 and 1012.5 tons (wet) respectively. The species of Hypnea and Sargassum could be exploited for the manufacture of phytochemicals.