H-44 



RESEARCH PROGRAMMES 



Ocean (Delepine, 1966 and in press; Neushul, 1968; Zaneveld, 1966). There are representatives 

 of 56 genera that have been utilized either as food or for the production of algal products in 

 many parts of the world. 



Worldwide the utilization of seaweeds is constantly increasing. Therefore, it can be 

 expected that attention in the future will be paid to the seaweed resources of the Antarctic and 

 sub- Antarctic. UtiUzation may take the form of human food, fodder for domestic animals, or 

 the production of agricultural fertilizers, phycocoUoids such as alginates, agar-agar and 

 carrageens and medicinal products such as antibiotics. 



It should be stressed that benthic marine algae are an important component of the coastal 

 ecosystems where they contribute significantly to the overall primary production. They also 

 provide a substantial food-source for many fishes and invertebrates, either directly or through 

 the detritus pathway, as well as a substrate and shelter for a wide range of animal species. In 

 addition, algae are known to excrete various substances in large quantities, but the role of these 

 substances in the ecosystem is not yet fully determined. 



Species of immediate interest in the Southern Ocean are the brown algae Macrocystis 

 pyrifera and Durvillea antarctica and the red algae 'Agarophytes' such as the Gelidiales or 

 Gigartinales (Gracilaria. Gigartina sp, etc). Some of the red algae are currently being exploited 

 in South America, South Africa and New Zealand. Quantitative information has been obtained 

 on Macrocystis pyrifera from the South Atlantic islands, and especially from Kerguelen, where 

 it is estimated that the beds cover more than 200 km^ , with biomasses ranging from 

 3.4-22.5 kg/m^ with means of 5-10 kg/m^. On New Zealand shores the standing stock of 

 Durvillea antarctica ranges from 10-20 kg/m^ . Standing stocks of a similar order of magnitude 

 have been recorded from the Kerguelen islands. 



2.9.2 Objectives 

 Research objectives are: 



1. To gain an understanding of the role of benthic algae in coastal ecosystems of the 

 Southern Ocean. 



2. To carry out basic studies on the potentially exploitable benthic algal species in the 

 Southern Ocean, and to assess the importance of this resource. 



2.9.3 Research programmes 



1. Stock estimation. 



(a) Mapping of the distribution of selected species. The use of satellite imagery for 

 this purpose should be explored. 



(b) Estimation of standing stock and primary productivity in selected habitats. Such 

 estimations should be carried out at different seasons and combined with 

 estimates of total standing crops for the species studied. 



(c) Resettlement and growth rates after clearing or harvesting in order to obtain 

 information on the subsequent history of the cleared or harvested areas as related 

 to the ecophysiology of the colonizing species. 



(d) Study of the vertical distribution of the algal standing crops. 



2. Ecophysiological studies. 



(a) In situ (phenological studies): to include studies on growth rates, productivity, 

 longevity, intensity of reproduction related to environmental factors such as light, 

 photoperiodicity, temperature, etc. 



(b) In the laboratory: studies to determine the ecophysiological reactions to 

 environmental factors for each phase of the life cycle; life cvcle studies. 



