BIO205H5 Chapter Notes - Chapter 22: Panama Canal Zone, Gatun Lake, Peacock Bass

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14 Dec 2018
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Bio205 chapter 22 - landscape ecology and biodiversity. Habitat destruction is the leading cause of current species extinctions. 140 000 km2 of tropical forest is lost each year. The largest cause of land transformation has been the expansion of agricultural lands to meet the needs of a growing human population. Quantity of forests alone is an inadequate indicator of the status of a forest ecosystem because many of the world"s forests are highly fragmented. Agricultural fertilizers, detergents, sewage, and industrial wastes add large amounts of nitrogen and phosphorus to aquatic ecosystems resulting in cultural eutrophication (increasing biomass and depleting o2 supplies in water; favouring growth of algae). Human introduced exotic species threaten many native species. Exotic/alien/invasive species are non-native plants and animals that are taken from their native habitats and placed somewhere else. Move away from predators, parasites, and competitors. Animal invaders often cause the extinction of vulnerable native species through predation, grazing, competition, and habitat alteration.