8.2 3.1.3 environment  (Page 16/8)

Concept of an environment

Throughout history humans have influenced and been influenced by the natural world. While much of our impact has been detrimental to the naturalenvironment, we have preserved and protected certain resources that are important to us. The environment, while highly valued by most, is used andaltered by a wide variety of people with many different interests and values. Difficulties remain on how best to ensure the protection of our environment andnatural resources, and how to divide the earth’s resources equally so that all benefit, and not just a select few.

There are currently many uncertainties regarding the future of the natural environment. However it is clear that humans have had a role in its destructionand will be responsible in the future for its conservation. Environmental problems are becoming more and more complex, especially as issues arise on amore global level, such as that of atmospheric pollution or global warming. There is a realization that such complex problems will demand complex solutionsand the participation of all.

The challenge is to find approaches to environmental management that give people the quality of life they seek while protecting the environmental systems thatare also the foundations of our well being. In order to face these challenges, students today will need more than superficial knowledge or awareness ofdisconnected environmental issues. A multidisciplinary approach to learning can build upon the strengths of a wide range of fields of study, providing a deeperunderstanding of the technological, political, and social options and strategies for both studying and managing the relationship between our societyand the environment. There will always be tradeoffs and, many times, unanticipated or unintended consequences.

Abiotic and biotic factors: effects on the community

There a number of characteristics of your local environment that can be classified into three broad categories, which can be called the“ABC’s of the environment.”

In the ABC’s of the environment,

A-refers to the abiotic (physical, non-living) features of the area

B- identifies the biotic (plant and animal) component of the environment.

C-C is the cultural (human) influences.

Some ecologists think of the ABC’s as forming a triangle with inter- relating sides. In a civilization as complex as ours, no single side can existuninfluenced by others.

How humans have an impact on the environment

The effect of humans on the composition of the atmosphere and the climate

This section will summarize some of the impacts that human’s have had on the environment. In particular we will look at the effect of humans on ourabiotic (non-living) environment.

Summary

Ozone Depletion: the ozone layer which prevents UV light from entering the earth’s surface is being destroyed by CFC’s and pollution

Greenhouse Effect: The UV light is being trapped within the earth’s atmosphere by a “blanket” of carbon dioxide and other greenhouse gasses, such asmethane and nitrous oxide. The main greenhouse gases are carbon dioxide and methane. They absorb much of the energy radiated from Earth and then re-radiateit back to Earth. The levels of these gases in the atmosphere are slowly rising. Carbon dioxide is produced when fossil fuels are burnt. Methane isreleased by cattle and from rice fields. An increase of only a few degrees Celsius may cause big changes in the Earth’s climate, upsetting weatherpatterns and affecting the types of crops that can be grown in different parts of the world. Polar ice caps may melt, causing the sea level to rise.