A tenfold increase in land area leads to a doubling

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A tenfold increase in land area leads to a doubling of the # of species c. Think of patches like islands d. The number of species on an island is a dynamic equilibrium between the immigration of new colonizers and the extinction previous colonizers e. Robert MacArthur and E.O Wilson’s theory of island biogeography i. Immigration decreases as the number of species increases ii. Extinction increases as the number of species increases iii. These two lines cross together at point S (equilibrium) iv. The immigration rate will be zero when all mainland species exist on the island
v. Equilibrium species richness (S) is affected by the distance of the island from the mainland and the size of the island VI. Patch connectivity a. Landscape connectivity - the extent to which a species (or population) can move among patches b. Structural connectivity - the degree to which patches are physically linked to one another c. Functional connectivity - the degree to which the landscape facilities the movement of species from patch to patch e.g. patches close enough together so fliers can move from one to the next. d. Corridors connect patches of similar habitat. They are strips are vegetation similar to the patches that they connect and are often human-made (windbreaks, ditches, drainage ditches) i. They facilitate movement ii. Can encourage gene flow between subpopulations iii. Can help reestablish species in habitats that have experienced local extinction iv. Different-sized gaps in corridors allow certain organism to cross while restricting others. v. Negatives are they offer scouting positions for predators and provide avenues for the spread of disease. they also allow for invasion of exotic species and invasive species. It too narrow, they can inhibit the movement of social groups. VII. Meta population and meta communities

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