We have affected ecosystems in almost every way imaginable! Every time we walk out in
the wilderness or bulldoze land for a new parking lot we are drastically altering an
ecosystem. We have disrupted the food chain, the carbon cycle, the nitrogen cycle, and the
water cycle. Mining minerals also takes its toll on an ecosystem. We need to do our best to
not interfere in these ecosystems and let nature take its toll.
Because we share the world with many other species of plants and animals, we must consider
the consequences of our actions. Over the past several decades, increasing human activity
has rapidly destroyed or polluted many ecological habitats throughout the world. It is
important to preserve all types of biomes as each houses many unique forms of life.
However, the continued heavy exploitation of certain biomes, such as the forest, freshwater,
and marine, may have more severe implications.
Forests are important as they are home to the most diverse biotic communties in the world.
Hidden within these biomes are potential medicines and many thousands of unseen and
undiscovered species. Also, forests have a global climate-buffering capacity, so their
destruction may cause large-scale changes in global climate.
Logging has depleted many old-growth temperate forests. The increased demand for homes,
paper, and other wood products have not allowed for much conservation. More recently,
people have begun to realize that logging has cleared much of these forests. Wiser use of the
WEEK 2:HUMAN INTERACTION AND POLLUTION
ACTIVITY LISTforests and efforts to replant trees have helped to slow down the depletion of these
Tropical forests have fallen victim to timber exploitation, slash and burn farming, and
clearfelling for industrial use or cattle ranching, particularly in Latin America. Our increasing
demand for meat products has spurred these events. For years, this destruction was occuring
at a rapid rate. Over half of the world's original tropical forests are already gone. Public
attention to this exploitation have helped to alleviate the problem somewhat, though many
challenges are still to be faced.
The freshwater and marine biomes are probably the most important of all the biomes. Their
medium, water, is a major natural resource. Water is the basis of life, it supports life, and
countless species live in it for all or part of their lives. Freshwater biomes supply us with our
drinking water and water for crop irrigation. The world's oceans have an even greater effect
on global climate than forests do. Water has a high capacity for heat, and because the Earth
is mostly covered with water, the temperature of the atmosphere is kept fairly constant and
able to support life. In addition to this climate-buffering capacity, the oceans contain several
billion photosynthetic plankton which account for most of the photosynthesis occuring on
Earth. Without these, there might not be enough oxygen to support such a large world
population and complex animal life.
Freshwater biomes have suffered mainly from pollution. Runoff containing fertilizer and other
wastes and industrial dumpings enter into rivers, ponds, and lakes and tend to promote
abnormally rapid algae growth. When these algae die, dead organic matter accumulates in
the water. This makes the water unusable and it kills many of the organisms living in the
habitat. Stricter laws have helped to slow down this thoughtless pollution.
Overfishing and pollution have threatened to make oceans into ecological disaster areas.
Industrial pollutants that are dumped upstream of estuaries have rendered many marine
habitats unsuitable for life. Again, tighter regulations have been used to prevent further
destruction of the ocean biomes