Download Chapter 50 Conservation Biology

Conservation Biology
Chapter 50
Mader: Biology 8th Ed.
Outline
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Biodiversity
– Value
 Direct Value
 Indirect Value
Causes of Extinction
– Habitat Loss
– Alien Species
– Pollution
– Overexploitation
Conservation Techniques
Mader: Biology 8th Ed.
Conservation Biology and Biodiversity
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Conservation biology studies all aspects of
biodiversity with the goal of conserving
natural resources for this generation and
future generations.
– Primary goal is the management of
biodiversity for sustainable use by
humans.
Mader: Biology 8th Ed.
Conservation Biology and Biodiversity
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Conservation biology supports certain
ethical principles.
– Biodiversity is desirable for the biosphere.
– Extinctions due to human actions are
undesirable.
– Ecosystem interactions supporting
biodiversity are desirable.
– Biodiversity brought about by evolutionary
change has value in and of itself.
Mader: Biology 8th Ed.
Mader: Biology 8th Ed.
Biodiversity
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At its simplest level, biodiversity is the
variety of life on Earth.
– Estimated that between 5 and 15 million
species currently exist.
Genetic diversity refers to variations among
the members of a population.
Community diversity increases biodiversity.
Landscape diversity involves a group of
interacting ecosystems.
Mader: Biology 8th Ed.
Biodiversity
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Some regions of the world are called
biodiversity hotspots because they contain
unusually large concentrations of species.
– Hotspots contain about 20% of earth’s
species, while only covering about 1% of
the land area.
Mader: Biology 8th Ed.
Value of Biodiversity
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Direct Value
– Medicinal Value
– Agricultural Value
 Crops
 Biological Pest Controls
 Pollinators
– Consumptive Use Value
 Wood
 Skins
Mader: Biology 8th Ed.
Value of Biodiversity
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Indirect Value
– Biogeochemical Cycles
– Waste Disposal
– Provision of Fresh Water
– Prevention of Soil Erosion
– Regulation of Climate
– Ecotourism
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Causes of Extinction
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Habitat Loss
– Occurred in all ecosystems, but recent
concern focused on tropical rain forests
and coral reefs.
 Habitat Fragmentation
Mader: Biology 8th Ed.
Habitat Loss
Mader: Biology 8th Ed.
Alien Species
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Alien species are nonnative species that
move, or are moved, into a new ecosystem.
– Often have competitive edge against
native species.
 Avenues of Human Introduction
 Colonization
 Horticulture and Agriculture
 Accidental Transport
Mader: Biology 8th Ed.
Pollution
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Pollution can be defined as any
environmental change that adversely affects
the lives and health of living things.
– Acid Deposition
– Eutrophication
– Ozone Depletion
– Organic Chemicals
– Global Warming
Mader: Biology 8th Ed.
Global Warming
Mader: Biology 8th Ed.
Overexploitation
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Overexploitation occurs when the number of
individuals taken from a wild population is so
great that the population becomes severely
reduced in numbers.
– Exotic Pets
– Hunting / Poaching
– Over-Harvesting Fisheries
Mader: Biology 8th Ed.
Trawling
Mader: Biology 8th Ed.
Conservation Techniques
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Habitat Preservation
– Keystone Species
Metapopulations
– Populations subdivided into several small,
isolated populations due to habitat
fragmentation.
 Source Populations
 Sink Populations
Mader: Biology 8th Ed.
Conservation Techniques
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Landscape Preservation
– Landscape protection for one species is
often beneficial for other wildlife species
that share the same space.
 Edge Effect
 Edge reduces the amount of habitat
because the edges around a patch
have a slightly different habitat than
the patch interior.
Mader: Biology 8th Ed.
Edge Effect
Mader: Biology 8th Ed.
Conservation Techniques
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Computer Analyses
– Gap Analysis
 Find gaps in preservation efforts.
 Try to identify areas where
biodiversity is high outside of
currently preserved areas.
 Population Viability Analysis
 Determine how much habitat a
species requires to maintain itself.
Mader: Biology 8th Ed.
Conservation Techniques
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Habitat Restoration
– Three Principles
 Begin as soon as possible before
remaining fragments are lost.
 Once natural history is understood, use
biological techniques to mimic natural
processes.
 Goal is sustainable development.
Mader: Biology 8th Ed.
Review
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Biodiversity
– Value
 Direct Value
 Indirect Value
Causes of Extinction
– Habitat Loss
– Alien Species
– Pollution
– Overexploitation
Conservation Techniques
Mader: Biology 8th Ed.
Mader: Biology 8th Ed.