How Do People Upset The Balance Of Nature Un 467043

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How do people upset the balance of nature? An environment is constantly changing. Sometimes, the changes work together to keep the environment in balance. In a balanced environment, the size of the population remains about the same over time. Sometimes the balance in an environment is upset. Many times people upset the balance of nature. They do this by destroying the habitats of other living things. For example, people cut down forests for farms and towns. They build dams and dig mines. All of these human activities can be harmful to other organisms in the environment. Many species of animals are finding it hard to survive because of the ways people have upset the balance of nature. People also upset the balance of nature by causing pollution. You probably know that pollution is a major problem. Pollution is anything that harms the environment. It occurs when harmful substances, or pollutants are released into the environment. Pollution of the air, land, and water are all major problems. Today many different substances are poisoning the environment and upsetting nature’s balance. And we cannot think of just air pollution, or just water pollution, or just land pollution. Pollution may start out in one part of the environment. But it does not remain there. It S-P-R-E-A-D-S to all parts. Pollution is increasing daily. Like other organisms, people also suffer from the effects of pollution – in the form of illness, birth defects, respiratory diseases, and many other problems. Therefore, we must all work together to help reduce pollution. Though we like to think that many disturbances of plant communities are reversible, even simple disturbances can cause permanent change. Old covered wagon routes across western North America are still visible more than one hundred years after they were used. Where the soil has been compacted, the growing conditions have changed. The trail ruts, not used for many years, still grow smaller plants and some different plant species. Will they ever look the same as the rest of the prairie grassland? No one really knows.

Some human disturbance is much more serious. Perhaps the most widespread serious damage humans are causing now is in the tropical rain forest. The complex plant and animal life in rain forests is used to make new products and has uses that we have just barely begun to discover and appreciate. Even more critical is the impact rain forests have on the chemical balance of our atmosphere. Today more and more people, industries, and countries use fossil fuels like coal, oil, and gas. When fossil fuels are used they release large amounts of carbon dioxide into the atmosphere. Rain forests, which use great quantities of carbon dioxide, are being destroyed. Scientists believe that the increase of carbon dioxide in our atmosphere is contributing to the long-term warming of our earth. This warming is called the “greenhouse effect”. The direct disturbance of plant communities by human activity does two things to the normal course of plant succession. First, it can simply start the successional sequence all over again. Second, it can actually affect the environment so much that it will take much longer or in some cases never again grow to the original climax community. It is hard to predict how permanent the effects of many direct human interactions with plant communities will be.

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ways that humans upset the balance of nature and affect succession.