Biodiversity and Conservation Chapter 5 Biodiversity and Conservation

Biodiversity Variety of species in a specific area. Richest environments for biodiversity are warm and moist biomes such as tropical rain forests, coral reefs, and tropical lakes. It increases the stability of an ecosystem.

Biodiversity Loss and Species Extinction Extinction – disappearance of a species when the last of its members dies Endangered species – a species numbers become so low that extinction is possible Threatened species – when a population of species is likely to become endangered

3 Types of biodiversity Genetic Diversity- the variety of genes in an ecosystem. This increases the chance that a species will survive. Species Diversity- number of different species and the abundance of each species. It increases as you move closer to the equator. Ecosystem Diversity- variety of ecosystems present in biosphere.

Importance of Biodiversity 1. Direct economic value- humans depend on plants and animals to provide food, clothing, energy, medicine, and shelter. 2. Indirect economic value- a healthy biosphere provides many services to humans and other organisms (oxygen, safe drinking water, etc) 3. Aesthetic and scientific values- some things are just beautiful or interesting to study.

Threats to Biodiversity Background extinction- gradual process of species becoming extinct Mass extinction- an event in which a large percentage of all living species become extinct in a relatively short time. *The last one was 65 million years ago.

Factors that threaten biodiversity Today’s high rate of extinction is different than past mass extinctions because it is a result of a single species- Homo sapien. 1. Overexploitation- excessive use of species that have economic value

2. Habitat loss – habitats that are destroyed due to human actions or extreme weather Ex. Cutting down the rain forest leads to loss of fertile land Ex. Coral reefs being destroyed by disease, temperature, pollution

3. Habitat fragmentation – separation of wilderness areas from other wilderness areas Contributes to extinction, change in biodiversity, invasion of exotic species, increases risk of fire

4. Habitat degradation (pollution) – damage to a habitat by pollution; such as air, water, and land Acid precipitation – rain, sleet, snow, and fog with low pH Pesticides use such as DDT poisoning animals through the food chain

5. Introduced Species- non-native species that are either intentionally or unintentionally transported to a new habitat. They are not a threat to their native ecosystem, but when introduced to a new one, can cause a disruption.

Conserving Biodiversity Human activities are destroying and degrading the habitats for many wild species and driving some of them to premature extinction. Sooner or later all species become extinct because they cannot respond successfully to changing environmental conditions. Current extinction rates are 100 to 10,000 times higher than natural extinction rates because of human activities.

What can we do? Limit our use of non-renewable resources (resources that are found on Earth in limited amounts or that are replaced by natural processes over long periods of time). Establish sustainable use (using resources at a rate at which they can be replaced or recycled while preserving the long-term environmental health of the biosphere

Protecting Biodiversity Establish protected areas – national parks Identify hot spots- areas that have high levels of endemic species (species only found in that area) and critical levels of habitat loss Create corridors between habitat fragments- safe passageways for organisms

Restoring Ecosystems Bioremediation- the use of living organisms, such as prokaryotes, fungi, or plants, to detoxify a polluted area Biological augmentation- adding natural predators to a degraded ecosystem.