Page 22 - Professorial Lecture - Prof Omoregie

 Nitrogen-rich fertilizers applied by farmers inland (for improved crop
yield), end up in local streams, rivers, and groundwater and are
eventually deposited in estuaries and bays.
 Excess fertilizers nutrients can spawn massive blooms of algae that rob
the water of oxygen, leaving areas where little or no marine life can exist.
Scientists have counted some 400 such dead zones around the world
(luckily Namibia is not included).
 UNDP 2006 estimated that nitrogenous (mainly nitrate and ammonium)
run-off to the marine environment are projected to increase at least 14%
globally by 2030.

Major Marine Pollutants – Crude Oil

(Source: UNEP, 1990)
 Usually occur as Oil spills during exploration, production and
transportation mainly as a result of accidents (which are usually
preventable in most cases under good governance and regulatory
framework).
 Natural disasters may cause spill as well.
 The heavy polycyclic aromatic hydrocarbons components which
constitute the dark oil droplet floating on water surface interfere with
primary productivity, thereby directly reducing biodiversity (Patin, 1999).

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