Detailed visual seabed survey at drilling site 7218/11-1
Detailed visual seabed survey at drilling site 7218/11-1
Detailed visual seabed survey at drilling site 7218/11-1
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5.3.3 Overall assessment of sponge densities <strong>at</strong> the Darwin <strong>site</strong><br />
Figure30 showsthe proportion of the variousspongedensitiesencounteredacrossthe <strong>survey</strong>area.<br />
Most of the areawasclassedashaving1-5 %coverof sponges,with similarproportionsof areaswith<br />
practically0 %sponges(seefiguretext) and5-10 %coverage.<br />
Figure30. Visual represent<strong>at</strong>ionof frequenciesof spongeabundanceclassesacrossthe study area. Upper:<br />
histogram showingactual numbersof observ<strong>at</strong>ionsand lower: pie chart expressingrel<strong>at</strong>ive frequenciesas<br />
percentages.Note th<strong>at</strong> 0 %abundance(not present)shouldbe consideredas 0-1 %.Seeimagesabove.There<br />
are seldom no spongesover many metres of <strong>seabed</strong>,thus 0 % is a m<strong>at</strong>ter of scale and timing (to the<br />
millisecond)of whenthe observ<strong>at</strong>ionwasmade.<br />
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