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Conservation of biodiversity - Coggle Diagram
Conservation of biodiversity
Rate of extinction
Before humans existed what it seems like there is probably one species per million species per year that went extinct whereas now the new estimate finds that species die off as much as 1,000 times more frequently than they used to making it ten times worse than the old estimate of hundred times.
Dodo
Is from the Island of Mauritius
Reasons of extinction
Arrival of Dutch in 1600s 2. Deforestation, invasive species (cats, dogs, rats) 3. Dodo were flightless, had short legs and had no adaptation to avoid predators.
Important terms of biodiversity
Biological biodiversity has two components; Richness = number of different species present. Evenness = how close in numbers each species is.
Indicator species & biotic indices
An indicator species is an organism whose presence, absence or abundance reflects a specific environmental condition.
A biotic index is a measure of the health of an ecosystem. Intolerant species score highly, so a clean ecosystem will have a higher biotic index than a polluted ecosystem.
Simpson's Diversity Index: D = N(N-1) divided by the sum of n(n-1)
Biotic Index: BI = The sum of (the number of individuals of a species x the tolerance rating of the species divided by the total number of individuals collected
Simpson's reciprocal index of diversity: D = N (N - 1) divided by the sum of all species n (n - 1)
What are ways that scientists use to determine the health of an ecosystem?
Looking at the biotic index, calculating the Simpson biodiversity index, and looking for species richness or species evenness when they count how many species are in that area.
Factors which affect biodiversity
Edge effect = boundaries between habitats or ecosystems. - At the edge of the forest, there is more sunlight, more wind and less moisture than at the center - Forest fragmentation - slipt in half by roads or farms - Exception: Cow birds thrives at the edge where it lays its eggs.
Disturbance generally will decrease biodiversity, but there are exceptions such as the cowbird.
Size
Large size vs. Small size
Large sites will avoid extinction with unexpected factors like fire or disease. Moreover, large sites provide more resources and breeding sites
Corridors = used to connect isolated populations - WWF established corridors between 40 isolated panda populations.
Active management of Endangered Species
Human intervention in conservation of an area.
Techniques to conserve an area
Restoration: restore land to natural state, recovery of threatened species, removal of introduced species, legal protection against development or pollution, captive breeding and reintroduction programs.
Conservation methods
In Situ: Conserve in own habitat. advantages: Species remain adapted to their habitat. Animals maintain natural behavior patterns. Species interact with each other, help to conserve the ecosystem. Presents GPS tagging of whales.
Ex situ: Conserve outside of own habitat. Advantages: Some species became too rare (last chance survival). Destruction of natural habitat can be necessary to remove threatened species. Captive breeding of pandas and seed banks store for replanting.