Ocean resources, their use and protection
The ocean is a treasury of natural resources: biological (fish, algae, marine animals), chemical (table salt, bromine, magnesium), mineral, and fuel-and-energy resources (oil, gas). The textbook gives 160 thousand animal and 10 thousand plant species; modern counts of described marine species run to hundreds of thousands (about 240 thousand), and many are still unknown. By habitat, organisms fall into three groups: plankton (drift with the water), nekton (swim freely, e.g. fish and whales) and benthos (live on the bottom). The heaviest animal is the blue whale (up to about 150 t). Seafood provides about 17 % of the animal protein of humanity. Oil and gas come mainly from the Persian Gulf, the coast of Venezuela, the North Sea and the Gulf of Mexico. Sea transport is the cheapest route: over 80 % of world trade cargo goes by sea (the textbook says over 60 %); there are more than 2 700 sea port cities. Ocean pollution is caused by tanker accidents, plastic waste and sewage. Protection is carried out at national, regional and international levels: the International Maritime Organization, the Intergovernmental Oceanographic Commission under UNESCO and others work on it.
“Ocean menu”: each group prepares a 1-minute “advert” for one ocean resource (fish, oil, salt, transport, tourism) and also says how to protect it.