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What can we do to prevent tropical countries to sell away their forests? What kind of
measures could be taken? Use logic and your imagination to answer these questions:
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Answers about water pollution:
Because of sewage problems, the Thames, England, in 1850 was badly polluted.
Untreated sewage can act as a damaging fertilizer causing excessive growth of plants and algae.
The organic matter in sewage acts as food for bacteria and as they use it they withdraw all the
oxygen from the water, thereby killing the fish. This is called EUTROPHICATION=”over-
enrichment:
Industrial wastes may contain chemicals and contaminants.
Drums of toxic wastes dumped at sea or washed overboard in a storm are washed up on the
beach. Those lost in the deep may leak.
Phosphates play the same role.
But Kutzu -vine plant cleans the water from pollution as a part of being beautiful.
Water may become choked with decaying algae, which severely depletes the oxygen supply.
This process, called eutrophication, can cause the death of fish and other aquatic life.
Agricultural runoff may be to blame for the growth of a toxic form of algae called Pfiesteria
piscicida, which was responsible for killing large amounts of fish from the Delaware Bay to the
Gulf of Mexico in the late 1990s.
The wearing away of topsoil by wind and rain causes water pollution. Soil and silt are washed
away from logged hillsides, plowed fields, or construction sites, then when falling in water ways
can clog them. This process can also kill aquatic vegetation and alter reproductive cycles of fish
by covering the gravel beds that fish use for spawning.
The Amazing Story of Kudzu:
Kudzu was introduced to the United States in 1876, at the Centennial Exposition in Philadelphia,
Pennsylvania. Many countries exhibited to celebrate the 100th birthday of the U.S.
Japanese built a beautiful garden filled with plants from their country.
The large leaves and sweet-smelling blooms of kudzu were loved by American gardeners who
used the plant for ornamental purposes.
It was also used as forage.
It was also promoted for erosion control.
Farmers were paid as much as eight dollars an acre as incentive to plant fields of the vines in the
1940s. It was even called "the miracle vine."
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