SNC1DW Chapter 3 Glossary Terms

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SNC1DW Chapter 3 Glossary Terms
2014-10-03 07:38:32
msday biodiversity

Glossary Terms for Chapter 3.
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  1. What is a biodiversity hotspot?
    A place where there is an exceptionally large number of species in a relatively small area. e.g. Carolinian Canada
  2. What does it mean to protect a species?
    To protect a species is to guard legally from harm to a species that is listed as endangered, threatened, or of special concern. This is critical to maintain biodiversity on Earth.
  3. What is biodiversity?
    Biodiversity is the number and variety of life forms, including species, found within a specific region. This includes all the number and variety of ecosystems within and beyond that region. A sustainable ecosystem is needed for a high biodiversity.
  4. What is a community?
    A community of all the populations of the different species that interact in a specific area or ecosystem. e.g. fish, corals, and sponges are all a part of the community in a coral reef. In a community, relationships include symbiosis, predation and competition. It is important to preserve biodiversity in a community to protect species in the community.
  5. What are dominant species?
    Dominant species are species that are so abundant that they have the largest biomass of any community member. In terrestrial ecosystems, dominant species are primary producers (e.g. plants), because consumer biomass is always less than the biomass of producers.
  6. What are keystone species?
    Keystone species are species that can greatly affect population numbers and the health of an ecosystem. Sometimes keystone species are not abundant, and are usually plants and animals. e.g. sea otters, which feed on sea urchins. During the fur trade, the otters were being hunted, causing an increase in the sea urchins, which feed on kelp. The biomass of the kelp decreased, which then the fish that depended on kelp forests for habitats had a smaller population.
  7. What is captive breeding?
    Captive breeding is the breeding of rare or endangered wildlife in controlled settings to increase the population size. e.g. the Toronto Zoo is breeding black-footed ferrets in the captive breeding program to bring the ferret back from almost extinction. The ferrets, once older, are then brought into the wild.
  8. What are ecosystem engineers?
    A species that causes such dramatic changes to landscapes that it creates a new ecosystem. e.g. beavers, which cut trees down to make dams. After a few weeks beavers can convert a small stream to an aquatic ecosystem. The dams create ponds which give nutrients for plants, and make clearings when cutting trees. Many organisms benefit from this beaver-pond ecosystem.
  9. What is habitat loss?
    The destruction of habitats, which usually results from human activities or natural disasters. Organisms can no longer survive there, and if they are unable to move to a different habitat, then they may not survive. Some ways of causing habitat loss includes volcanoes, wildfires, and deforestation.
  10. What is deforestation?
    The practice of clearing forests for logging or other human uses, and never replanting them. e.g. annual deforestation rates in Canada's vast boreal plains ecosystem from 1966-1994 were almost three times the average deforestation rate worldwide. Deforestation affects the species that lived in the forest, which threatens biodiversity.
  11. What are alien and invasive species?
    Alien species - a species that is accidentally or deliberately introduced to a new location. e.g. monitor lizards were introduced to new land to eat rats when the rat population grew, but the lizards and rats never met e.g. ships accidentally bring in species from ballast waters.

    Invasive species - a species that can take over the habitat of native species. e.g. zebra mussels were brought to the Great Lakes through ballast water. Shrimp-like crustaceans that shares food with zebra mussels have decreased, which then affects higher trophic levels.
  12. What is overexploitation?
    Overexploitation is the use or extraction of a resource until it is depleted. Biodiversity is threatened. It can lead to very low population numbers, and even extinction. e.g. passenger pigeons, whose population was once about 5 billion, but because of hunting and other factors, the population is extinct, rather, in the 1900s.
  13. What does it mean when a species is extinct?
    The death of all the individuals of a species. This occurs when the death rate of a species remains higher  than the birth rate for a long period of time. Sometimes extinction occurs because of human activities, or because biotic or abiotic factors in an ecosystem change. e.g. a decline in rainfall can make a plant species go extinct, or a new insect species way of eating plants causes them to go extinct.
  14. What is biodiversity crisis?
    The current accelerated rate of extinctions. This is usually caused by humans, by deforestation, habitat destruction, air and water pollution, etc, and changes the biotic and abiotic factors to such an extent that organisms are unable to survive.
  15. What is stewardship?
    The active assumption of responsibility for the welfare of the environment. Ethical reasons for stewardship is that we look after the biosphere for other human beings and future generations, so we should take care of our environment.
  16. What is restoration ecology?
    The renewal of degrade or destroyed ecosystems through active human intervention. the major goal is to stimulate natural processes of regeneration to make and ecosystem identical to the one lost. e.g. the Don Valley brick Works was restored to a healthier state by filling the quarry with material from Toronto, and the site was landscaped to make three ponds, which captured sediment and filtered the water. It also provides habitats for many organisms.
  17. What is reforestation?
    The regrowth of a forest, either through natural processes or through the planting of seeds or trees in an area where a forest was cut down. This is an example of restoration ecology. e.g. red pine trees were planted in areas without trees, and many years later, native trees which used to grow there returned, and provided habitat for many organisms.
  18. What is biocontrol?
    The use of a species to control the population growth or spread of an undesirable species. e.g the European gypsy moth was accidentally released in the forests of North America. A European fly called the parasitoid was introduced to eliminate the moth, by laying its eggs inside the moth and eventually killing it. Even though the fly killed other moths, it regulated the population of the gypsy moth.
  19. What is bioremediation and bioaugmentation?
    • Bioremediation - the use of living organisms to clean up contaminated areas naturally. e.g. specific plants are grown at toxic sites to clean soils by collecting poisons on their tissues.
    • Bioaugmentation - the use of organisms to add essential nutrients to depleted soils. e.g. clover are used to replenish nitrogen levels in soils, which is an important nutrient for plants to grow. Farmers use clovers to replenish their farmland with nitrogen