BIO.B.4 Ecology
Topic Summary for Human Interactions:
Humans and other organisms change the environment when they obtain food, eliminate wastes, and prepare places to live.
Because Earth is like an island, life is limited to the resources that are here.
Humans affect regional and global environments through three major activities:
• agriculture, particularly monoculture, which is the cultivation of a single crop
• development of cities and suburbs, including conversion of farmland and destruction of habitats for other organisms
• industrial growth, which consumes energy and emits pollutants
In economic terms, ecosystems are providers of goods and services (natural resources).
Healthy ecosystems produce or replace renewable resources.
Humans must be careful about the use of nonrenewable resources, such as fossil fuels, which cannot be replaced.
Sustainable development provides for human needs while preserving the ecosystems that provide renewable resources.
Soil Resources
Soil is a renewable resource, but it must be managed properly.
Soil erosion is the wearing away of surface soil by water and wind.
In dry climates, farming and overgrazing change farmland into deserts, a process called desertification.
Deforestation is loss of forests. Because healthy forests hold soil in place, deforestation increases erosion.
Sustainable uses include leaving stems and roots of previous crops in place, crop rotation, contour plowing, terracing, selectively harvesting mature trees, and tree farms.
Freshwater Resources
The amount of fresh water is limited, and some sources cannot be replaced.
A pollutant is a harmful material that can enter the biosphere. Water pollutants come from industrial chemicals, residential sewage, and other sources.
Many chemical pollutants become concentrated in organisms at higher trophic levels of the food chain through biological magnification.
Sustainable uses include conservation, pollution control, and watershed protection.
Atmospheric Resources
Clean air is important to human health and Earth’s climate. Pollution reduces air quality.
Smog is a mixture of chemicals formed from emissions from cars and industry.
Burning fossil fuels releases compounds that join with water in air, forming acid rain.
Greenhouse gases, such as carbon dioxide and methane, can cause global warming.
Particulates are microscopic particles that cause health problems.
One way of sustaining air quality is controlling automobile emissions.
The ecological footprint of an individual or a population is the amount of land and water needed to provide resources, absorb wastes, and render the wastes harmless.
There are three steps of ecology in action: (1) recognize a change in the environment, (2) determine the cause of that change, and (3) change behavior to have a positive impact.
Topic Summary for Human Interactions:
Humans and other organisms change the environment when they obtain food, eliminate wastes, and prepare places to live.
Because Earth is like an island, life is limited to the resources that are here.
Humans affect regional and global environments through three major activities:
• agriculture, particularly monoculture, which is the cultivation of a single crop
• development of cities and suburbs, including conversion of farmland and destruction of habitats for other organisms
• industrial growth, which consumes energy and emits pollutants
In economic terms, ecosystems are providers of goods and services (natural resources).
Healthy ecosystems produce or replace renewable resources.
Humans must be careful about the use of nonrenewable resources, such as fossil fuels, which cannot be replaced.
Sustainable development provides for human needs while preserving the ecosystems that provide renewable resources.
Soil Resources
Soil is a renewable resource, but it must be managed properly.
Soil erosion is the wearing away of surface soil by water and wind.
In dry climates, farming and overgrazing change farmland into deserts, a process called desertification.
Deforestation is loss of forests. Because healthy forests hold soil in place, deforestation increases erosion.
Sustainable uses include leaving stems and roots of previous crops in place, crop rotation, contour plowing, terracing, selectively harvesting mature trees, and tree farms.
Freshwater Resources
The amount of fresh water is limited, and some sources cannot be replaced.
A pollutant is a harmful material that can enter the biosphere. Water pollutants come from industrial chemicals, residential sewage, and other sources.
Many chemical pollutants become concentrated in organisms at higher trophic levels of the food chain through biological magnification.
Sustainable uses include conservation, pollution control, and watershed protection.
Atmospheric Resources
Clean air is important to human health and Earth’s climate. Pollution reduces air quality.
Smog is a mixture of chemicals formed from emissions from cars and industry.
Burning fossil fuels releases compounds that join with water in air, forming acid rain.
Greenhouse gases, such as carbon dioxide and methane, can cause global warming.
Particulates are microscopic particles that cause health problems.
One way of sustaining air quality is controlling automobile emissions.
The ecological footprint of an individual or a population is the amount of land and water needed to provide resources, absorb wastes, and render the wastes harmless.
There are three steps of ecology in action: (1) recognize a change in the environment, (2) determine the cause of that change, and (3) change behavior to have a positive impact.