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23 Cards in this Set
- Front
- Back
Ecosystem services
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Encompass all the processes through which natural ecosystems and the species they contain help sustain human life on Earth.
Services include: Purification of air and water. Detoxification and decomposition of wastes. Nutrient Cycling Moderation of weather extremes. Many more. |
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Endangered/Threatened Species
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Endangered: Species that is in danger of becoming extinct throughout is range.
Threatened: Species that are likely to become endangered in the forseeable future. |
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Three Levels of Biodiversity
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Genetic Diversity
Species Diversity Ecosystem Diversity |
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1/3 Levels of Biodiversity:
Genetic Diversity |
Genetic variation within and between populations. Low diversity = biological malformation = potential extinction.
Genetic Diversity is the sum of all the alleles in a population. |
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1/3 Levels of Biodiversity:
Species Diversity |
Variety of species within an ecosystem or biosphere. High diversity means many species and many individuals of each species.
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1/3 Levels of Biodiversity:
Ecosystem Diversity |
Identifies the variety of ecosystems in the biosphere. Is being affected by human activity.
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Five Major Threats to Biodiversity
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HIPPO:
Habitat Loss Invasive Species Pollution Population (human) Overexploitation |
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Habitat Loss
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Single greatest threat to biodiversity. Scrubland is highest at 29% of species expected to go extinct, Temperate forests right behind it.
Habit fragmentation and destruction leads to loss of biodiversity. |
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Introduced Species
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Species that humans move from species' native location to new geographic region. 4 out of 5 birds in the area are introduced.
Brown tree snake: responsible for mass bird extinction in S. Pacific. Kudzu: taking over millions of acres in the south. # of exotic plants (highest-lowest): New York, California, Florida). highest concentration in NE. |
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Overexploitation
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Human harvesting of wild plants or animals at rates exceeding the ability of populations to rebound.
Ocean most in danger due to lack of regulation. |
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Pollution
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Chemicals introduced into a biosphere.
DDT: pesticide used in 50's/60's. Accumulated in birds-of-prey. Bald eagle population plummeted. Rebounded since banning of DDT. |
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Human Population
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6.7 Billion humans require massive amount of resources
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Extinction Vortex
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Small populations prone to positive-feedback loops that draw the population down into an extinction vortex.
Key driving factor is loss of Genetic Variation. |
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Minimum Viable Population Size (MVP)
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MVP: Minimum population size at which a species is able to sustain it's numbers and survive.
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Population Viability Analysis (PVA)
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Predicts a population's chances for survival over a particular time. Factors in the MVP of a population.
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Declining Populations
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Populations that are less abundant than historically, yet not so rare as to be in imminent danger of extinction. Populations that show a downward trend towards long-term extinction.
Emphasizes the environmental factors that caused a population to decline in the first place. |
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Declining population approach
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Evaluate populations on a case-by-case basis. Must be able to distinguish declining population from variable.
Red-Cockaded woodpecker:: With the experiment, a new combo of habitat maintenance and excavation of new breeding cavities has brought a species back from endangered. |
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Landscape and Regional Conservation
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Aim to sustain entire biotas through Multiple Use: preserve entire ecosystem and conserve it, while still allowing for regulated industrial consumption.
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Dangers of fragmentation
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Creates proportionally more "edges", which causes biodiversity to decrease. Also isolates populations.
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Corridors
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Narrow strip of quality habitat connecting otherwise isolated patches. Seeks to alleviate problems with small populations.
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Biodiversity Hot Spot
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A relatively small area with an exceptional concentration of endemic species, and a large number of threatened or endangered species.
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Two Key strategies in Restoration ecology
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Bioremediation: Use of living organisms to detoxify ecosystems.
Augmentation: Reintroduction of biological life. |
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Sustainable Biosphere Initiative
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The goal of this intiative is to define and acquire the basic ecological information necessary for the intelligent and responsible development, management, and conservation of Earth's resources.
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