Page 27 - Professorial Lecture - Prof Omoregie

(Raghukumar et al. 2001) as well as direct impacts on organisms (Bluhm, 1994;
1999; Shirayama, 1999; Ingole et al. 1999).

In addition, Markussen (1994) reported that the propulsion system of the
collector unit will stir up sediments; as a result, organisms in and around the
tracks will be partially or entirely buried. In the mining tracks, for instance, a
mortality rate of
95 – 100% may be expected for organisms found there.

The BCLME is already a zone of sporadic sulphide eruption due to certain
biochemical process taking place within the sediments. Director of Ceremonies,
Ladies and Gentlemen, let me state categorically clear, that disturbance to the
nutrient-rich sediment of the BCLME is likely to set up series of events that would
further aggravate the incidence of sulphide eruption. One of such events will be
the additional load of nutrients into the water column (from within the
sediments)  with the result effects of de-oxygenation in the water column
(devastating for both the aquaculture and fishing industries).

The process of concentrating phosphorite mud at sea through screening and then
de-sliming and the eventual treatment in a phosphoric acid plant are series of
events that lead to increasing levels of certain mineral elements in the water
column as well as increasing acidification.

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