Environmental Concerns Bio.2.2.1 Infer how human activities (including population growth, pollution, global warming, burning of fossil fuels, habitat destruction and introduction of nonnative species) may impact the environment Bio.2.2.2 Explain how the use, protection and conservation of natural resources by humans impact the environment from one generation to the next.

Atmosphere Important parts of the atmosphere are greenhouse gases, which trap heat on Earth, and the ozone layer, which shields Earth from UV The atmosphere’s ability to trap heat is called the greenhouse effect.

The rest of the Bioshpere The biosphere includes all parts of Earth where life exists. A very small portion of the hydrosphere is fresh water, and much of this fresh water is not easily usable. The geosphere exchanges materials with the atmosphere, hydrosphere, and biosphere.

Biodiversity Biodiversity refers to the variety of life found in an area. Biodiversity can be measured in different ways, including by species richness, species evenness, and genetic diversity. Species richness – the number of different species Species evenness – how close in numbers each species is Genetic diversity – total number of genetic characteristics in the genetic makeup of a species

Pollution Ozone Thinning Industrial chemicals called chlorofluorocarbons (CFCs) act as catalysts in chemical reactions that break down O3 molecules in the ozone layer. Most countries have banned CFCs, and the ozone layer seems to be recovering.

Pollution Global Warming The correlation of increasing atmospheric CO2 and rising global temperature suggests a cause-and- effect relationship. Considering several types of evidence, many scientists have concluded that increased CO2 levels have caused warmer surface temperatures on Earth.

Pollution Acid Precipitation Air pollutants such as sulfur cause acid precipitation, which harms or kills many organisms.

Pollution The release of toxic chemicals, such as DDT, into the biosphere can impact ecosystems in many ways, especially when chemicals undergo biological magnification.

Extinction Human impacts on the environment are causing an increasing number of extinctions. Important causes of extinctions are habitat destruction, the transfer of invasive species to new habitats, harvesting, and hunting. This loss of species has both known and unknown effects on ecosystems. Species such as the sea otter that affect many other species in a community are called keystone species.

Conservation and Restoration Biology Conservation biologists are concerned with identifying and maintaining ecosystems, while restoration biologists are usually involved with repairing badly damaged ecosystems. Species and Habitats A bioindicator is a species that is especially sensitive to ecological change.

Conservation and Restoration Biology Case Study: Saving the Whooping Crane Populations of many migratory birds, such as the whooping crane, are in decline because of human activities. However, some populations are recovering as a result of legal protection, breeding programs, habitat restoration, and international partnerships.

Protecting Ecosystems Biodiversity Hotspots International and cooperative efforts to preserve habitat and prevent extinctions include identifying biodiversity hotspots, making debt-for-nature swaps (preserve your country’s environment and this country will forgive some or all of your debt) , and promoting ecotourism.

Conservation Case Study: The Everglades The Everglades restoration project is the most ambitious ecosystem-wide restoration project attempted in the United States. Authorized by congress in 2000 to “restore, preserve, and protect south Florida ecosystem while providing for other water-related needs of the region, including water supply and flood protection.”