Page 28 - Professorial Lecture - Prof Omoregie

One should also bear in mind that in any large scale mining operation, accidents
do occur.

Environmental consequences of accidents associated with mining operations at
the sea are usually catastrophic. A recent example is the BP Gulf of Mexico deep
water oil-spill (analysts put the total economic lost at over US$ 20 billion to date)
and ecologists are of the opinion that it will take over 100 years for the lost
biodiversity of the Gulf of Mexico to return (only in the absence of another major
spill).

Negative Impacts of Phosphorus Pollution
 Phosphorus is the nutrient that “limits” (is most essential to) aquatic
plant (inclusive of phytoplankton) growth. However, excess of
phosphorus lead to excess plant growth, leading to eutrophication (
phytoplankton bloom).

 Eutrophication is accompanied by increased demand for oxygen (by
resident bacteria) in decomposing organic matters in the sediments. If
there is no replacement for the used oxygen (by photosynthetic activity),
hypoxia sets in leading to reduced biodiversity.

 Blooms of blue-green algae directly lead to production of neurotoxins
(affecting the nervous system) and hepatoxins (affecting the liver), which
can cause reduced productivity in terms of fishery and aquaculture.

 Blooms directly create hypoxic condition in the water (de-oxygenation –
directly reducing in death of highly sensitive fish and shellfish).

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