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- def: the number and variety of organisms, including species, found within a specific region
- e.g: almost 5000 species of plants have been found in Canada
- each species plays an important role in maintaining sustainable ecosystems
- def: to guard legally from harm a species that is listed as endangered, threatened, or of special concern
- humans must protect ecosystems because, what happens in one ecosystem can affect many other ecosystems and species
- def: a place where there is an exceptionally large number of species in a relatively small area
- e.g: Carolinian Canada in southwestern Ontario
- def: all the populations of the different species that interact in a specific area or ecosystem
- these are important in the preservation of biodiversity because many species depend on these interactions
- def: species that are so abundant that they have the biggest biomass of any community member
- e.g: in terrestrial ecosystems, the dominant species is always the primary producer
- removing a dominant species will result in a decrease in biodiversity in an ecosystem
- In this picture, the grass is the dominant species.
- def: a species that can greatly affect population numbers and the health of an ecosystem
- generally not abundant
- can be plants or animals
- def: the breeding of rare or endangered wildlife in controlled settings to increase the population size
- there are programs designed to bring these animals back from being close to extinction
- e.g: the populations of prairie dogs were greatly reduced when people trapped, poisoned, and shot them because they considered them as pests. Wild prairie ecosystems began to suffer because of the lack of this keystone species and animals like the black-footed ferret who used the burrows of the prairie dogs began to decrease in numbers also. Different facilities brought the ferrets into captive breeding and once there was enough, they were able to be released back into the wild.
- Prairie dog in the background and black-footed ferret in the foreground.
- def: a species that causes such dramatic changes to landscapes that it creates a new ecosystem
- e.g: in a few weeks, beavers can convert a small stream in a forest to fit their needs. They build dams across streams to create ponds for safety and to provide food and cut down trees to make small clearings in the forest.
- def: the series of changes in an ecosystem that occurs over time, following a disturbance
- e.g: in a beaver pond, the area changes from a forest to a flooded forest, then a pond, which eventually is abandoned and becomes a beaver meadow. Each stage is important for different species.
- Beaver meadow
- def: the destruction of habitats, which usually results from human activities
- e.g: deforestation for logging and draining wetlands for farming, construction, or mosquito control
- def: the practice of clearing forests for logging or other human uses, and never replanting them
- e.g: deforestation in tropical rainforests (biodiversity hotspots) has resulted in the loss of 20-50% of forests in some countries
- def: a species that is accidentally or deliberately introduced into a new location
- alien species that become invasive species can take over the habitat of native species
- e.g: zebra mussels (from Asia) were introduced to the Great Lakes through ballast water in the 1980's. They can outcompete native species that share the same food as a resource and impact other levels of the food chain.
- zebra mussels in Lake Texoma on the Oklahoma boarder
- def: a species that can take over the habitat of native species
- e.g: round gobies were introduced in ballast water in the late 1980's and competes with native fish for spawning areas. They also eat many other aquatic species such as snails, other fish, and fish eggs, which impacts the food chain and the biodiversity of the ecosystem.
- (same idea as the example for alien species)
- def: the use or extraction of a resource until it is depleted
- e.g: over fishing of Atlantic cod, over hunting of passenger pigeons
- def: the death of all the individuals of a species
- may happen naturally through slow changes in the ecosystem that affect the species, or through mass extinction which occurs much quicker
- may be caused by human activities, such as overexploitation
- def: the current accelerated rate of extinctions
- the current extinction rate is estimated to be 100 to 1000 times higher than a normal rate
- many species risk extinction, which causes this crisis
- def: the renewal of degraded or destroyed ecosystems through active human intervention
- e.g: restoration methods include: reforestation, wetlands restoration, controlling alien species (using biocontrol or chemical control), bioremediation and bioaugmentation
- def: 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
- e.g: in the early 1900's, red pine trees were planted in eastern Canada where they had previously been cleared for agriculture. As the forest grew back, it also reintroduced native species such as: sugar maple, American beech, hickory, and ash.
- def: the use of a species to control the population growth or spread of an undesirable species
- e.g: use of a European fly to control the gypsy moth or the use of bacteria spraying to control tent caterpillars and other forest pests
- (form of the restoration method of Controlling Alien Species)
- tent caterpillar nest
- def: the use of living organisms to clean up contaminated areas naturally
- e.g: use of plants to absorb heavy metals from toxic soil or the use of bacteria to clean up oil spills on the coast
- def: the use of organisms to add essential nutrients to depleted soils
- e.g: use of clover to add nitrogen to depleted soils