GEOG 125 Lecture Notes - Lecture 4: Primary Production, Habitat Fragmentation, Habitat Destruction
Document Summary
Net primary productivity shared among species used, destroyed, or degraded to support human activities. Elimination of natural biotic communities; often consists of replacement with monocultures. Alteration of ecological succession through changes to disturbance. Alteration of ecological succession through changes to disturbance patterns (ex; changing fire frequencies) Internal fragmentation: incursions into interior of extensive habitats. Indirect impacts; alteration of habitats, alteration of nutrients cycles. Greenhouse gases; modify global weather patterns, increase frequency of extreme weather. Most animals and plants not be able to cope. Alteration of natural chemical cycles and bnergy flows. Threatened: species may become endangered in the near future. Endangered: species in imminent danger of becoming extirpated or extinct. The disappearance of a population from a given area within its ranger; not the entire species globally. Occurs when the last member of a species dies and the species ceases to exist. Species at risk: premature extinction birds mammals reptiles.
