Transcript Restoration Ecology

Restoration Ecology
Key terms
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Intervention
Mitigation
Reallocation
Reclamation
Re-creation
Rehabilitation
Remediation
Restoration
Characteristics of Species Prone To
Extinction
The 6th Mass Extinction
• Estimate: 50,000 species per year
• Global declines in genetic diversity of wildlife
seen; leads to inbreeding depression
• Global declines in genetic diversity of
crops/livestock
• Global declines in species diversity
• Global declines in ecosystem function
The 6th Mass Extinction
Causes of Declining Biodiversity
• Loss of Habitat
• Alien species (non-native/exotic) if they
spread rapidly, → Invasive
• Population
• Pollution
• Climate change
• Overharvesting
Habitat
Invasive Species
Population
Pollution
Climate Change
Overharvesting
Helping Nature Heal
• Humans have disturbed and degraded nature
for as long as we have existed
• We are able to repair some of the damage
(ecological restoration)
• Recovery: linked to the idea “natural climax
community will return if we leave it alone”
• Modern Ecology: this may not be the case
(random process)
Helping Nature Heal
• Aims of restoration driven by human values
(beauty, recreation, utility) rather than science
• General principles of restoration are drawn
from ecology, hydrology, soil science, etc.
• Most influential American forester: Gifford
Pinchot*
• Another pioneer: Aldo Leopold
Gifford Pinchot
• Introduced selective harvest and replanting of
choice tree species
• This increased the value of the forest
• Also produced a sustainable harvest
• First head of U.S. Forest Service
Habitat Destruction
• Deforestation is the greatest eliminator of
species,) followed by coral reefs & wetlands
• Fragmentation (roads, logging, agriculture)
• Increase vulnerability
• Changes migratory patterns (buildings, etc.)
• Case Study: Birds as indicators (p 195 – 197)
Invasive Species
Characteristics of Successful Invasive Sp.
Characteristics of Vulnerable Ecosystems
r-selected species
Climate similar to habitat of invader
Pioneer species
Absence of natural predators
Long lived
Early successional systems
High dispersal rate
Low diversity of native species
Generalists
Absence of fire
High genetic variability
Disturbed by human activities
Invasive Species
Controlling Invasive Species
Do not capture or buy wild plants and animals
Do not remove plants and animals from natural areas
Do not dump aquarium contents into waterways, wetlands, storm drains
Use wood found near your camp site
Do not dump unused bait into waterways
Brush your dog’s fur after being in woods or water
Clean recreational vehicles/gear before going home
CONSERVATION OF BIODIVERSITY
FOCUSING ON SPECIES
Laws and Treaties
• Lacey Act, 1900; many amendments; forbids
interstate trade of illegally harvested plants
and animals
• Convention on International Trade in
endangered Species (CITES), 1975; 175
countries
• Marine Mammal Protection Act, 1972
Laws and Treaties
• Endangered Species Act, 1973; amended in
‘82, ‘85, ‘88
• ESA implements CITES agreement
• US Fish and Wildlife Service is main overseer
• Controversial at times; spotted owl v. logging
in NW US during 1990s
Laws and Treaties
Convention on Biological Diversity (1992)
• Conserve biodiversity
• Sustainably use biodiversity
• Share the benefits that emerge (ex – pharmaceuticals)
Other Methods
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Wildlife refuges
Gene/seed banks
Botanical gardens
Wildlife farms
Zoos and aquariums
Nature Can Be Resilient
• First step in restoration: stop whatever is
causing the damage
• Ex. – prohibiting logging, mining, etc., may be
enough to allow nature to heal by itself
• Sometimes rebuilding populations of native
plants and animals is a simple process of
restocking breeding individuals to an area
Video Focus Questions: Forest Fires
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Climate impact on frequency, intensity of fires
Human impact on frequency, intensity of fires
Natural recovery from fires
Restoration efforts
Importance of forests
CONSERVATION OF BIODIVERSITY
FOCUSING ON ECOSYSTEMS
Forest Restoration
• Lumber companies routinely replant forests that
they have harvested
• Mechanical restoration results in a monoculture
of uniformly placed trees
• Japan was almost completely deforested at the
end of WWII, now more than 60% is forested
• Today: Largest reforestation in China; 50 billion
trees have been planted over the past 50 years
Forest Restoration
• Urban planting important
• 2007: UN announced “billion tree campaign”
• Historically, fire has been important in
controlling vegetation in savannas
• Settlers eliminated fire and grazing by native
animals → shrub and tree growth
• Accumulated veg. is cleared before fires are
started; herbicides prevent re-growth
Forest Restoration
• Sequoia National Park: 70 years of fire
suppression → dense undergrowth → more fuel
for destructive fires
Prairie Restoration
• Before European settlement, prairies covered
most of the middle U.S.
• Tall-grass: eastern edge of the Great Plains. Less
than 2% remains
• Fire is also crucial for prairie restoration; kills
many weedy species and removes nutrients (esp.
N)
• The Nature Conservancy has established many
preserves to protect tallgrass prairies
Prairie Restoration
• Huge areas of short-grass prairie are being
preserved
• Bison help maintain prairies; with fire, an
important tool in restoration
Wetland and Stream Restoration
• Wetlands occupy < 5% of US land; 1/3 of all
endangered species spend at least part of their
lives in wetlands
• Until recently governments encouraged drainage
for development
• 1972 Clean Water Act began protecting streams
and wetlands by requiring discharge permits for
dumping waste into sfc waters
Wetland and Stream Restoration
• For wetlands, sometimes all that’s needed is to
stop destructive forces
• The Everglades is a fresh water river that comes
from springs that has been diverted, causing 90%
of wading birds to be lost
• It is hoped that by restoring the former flow will
allow the biological community to recover
Wetland and Stream Restoration
• The Chesapeake Bay is a drowned river valley
with fresh and salty water mixing
• Overfishing, sewerage discharge, silt, heavy
metals, toxic chemicals from industry and
agriculture, oil spills and habitat destruction are
causing a loss of productive fisheries
• Restoration = minimal success
Wetland and Stream Restoration
• Cities: artificial wetlands provide a low-cost way
to filter sewerage
• Stabilizing stream banks, stopping pollution,
controlling invasive species, preventing erosion
are restoring streams
• Remediation means finding remedies from
problems involving noninvasive techniques
• Reclamation implies using intense physical or
chemical methods to repair ecosystems