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very low everywhere, The rising to the surface of 
water of deeper layers that is poorer in 0, is not 
recognisable because, with the very slow rising of 
the water, oxygen is generated in the euphotic layer 
by photosynthesis and additionally taken up from the 
atmosphere, The lower water layers show only a slight 
oxygen consumption, Hence it follows that primary 
production in the area of investigation, compared 
with the centre of the upwelling area further south, 
is relatively low. 
NKeierencesi 
See pages 9 and 
10