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THE DAMAGED ENVIRONMENT -HOW LONG WILL IT LAST?
Man has influenced the environment in three very different ways: a dramatic reshaping of the landscape to create efficient agriculture and urban life; a major interference in the biogeochemical cycles of carbon, nitrogen, phosphorus and metals changing the physics and chemistry of the environment through increased nutrient flows, acidification, global warming, and increased UV radiation; thousands of chemicals, foreign to the planet and its life forms, have been used extensively in the environment, some of them deliberately to poison life.
The pollution chain is the way that pollutants take from production into the environment over air and water. Some chemicals are easily taken up by life forms, they are bio-available, they may accumulate in organs and tissues, stay in the food chains as they migrate from prey to predator, even from the mother to the child. Many of them also end up in man.
Chemicals have special effects on ecosystems. An ecosystem might be completely disrupted if one key species is badly damaged, and prey-predator relationships are changed. Typically ecosystems hit by pollution lose diversity and biomass. At the same time environments that are less diverse, both as landscapes and as ecosystems are more vulnerable to environmental impacts.
Compared to the 1950's and 1960's, when the threat from chemical pollution was first grasped seriously, much has happened. Many chemicals have been banned and new chemicals have been designed so they do not accumulate in ecosystems. But old chemicals still leak from the society into the environment, and new threats are continuously discovered. Lately pollutants that influence the sexual differentiation in animals, the so called endocrine disruptors; have been creating a new scene, a chemical panorama that seems more threatening than before. It is discussed whether endocrine disruptors, also called hormonal-mimetic pollutants, can reach man and threaten his reproduction. Environmental impacts interact in several ways, either to reinforce one another or sometimes dampen each other. Landscape changes make the environment more less susceptible for eutrophication and acidification.
What are the most hazardous side-effects of improvement of the environment?
Choose the correct preposition:
1. The pollution chain is the way that pollutants take from production
into the environment................................................ air and water.
(over; by; on)
2. We will study how these types of pollution and environmental impact
spread........................................... the environment.
(in; into; to)
3. At the same time environments are more vulnerable...............................................
environmental impacts. (to, at, on)
4. Some of the impacts that man has had.................................... the environment
will last very long. (to; at; on)
5. Our children will live....................................... an environment that is a little
(in; with; into)
less rich and a little less diverse than ours.
1. The pollution chain is the way that pollutants take from the environment into air and water.
2. Typically ecosystems hit by pollution lose diversity and biomass.
3. Many new chemicals have been designed specially to accumulate in ecosystems.
4. Landscape changes make the environment not susceptible for eutrophication and acidification