Transcript BIODIVERSITY

BIODIVERSITY
“The last word I ignorance is the person who says
of an animal or plant: ‘What good is it?’… It the
land mechanism as a whole is good then every part
of it is good, whether we understand it or
not…Harmony with the land is like harmony with
a friend; you cannot cherish his right and chop off
his left.” Aldo Leopold
What is Biodiversity
• Genetic biodiversity
• Species diversity
– Endangered, threatened, extinct species
• Ecological (ecosystem) diversity
Species
• Defining a species
• Problems with definition
– Hybridization
– Geographical isolation
– Morphological
• Genetic fingerprinting (pawprinting :-)
• Real life application - the red wolf
– Can a subspecies be protected? – not according to ESA
How Many Species
• Over 2 million known
• Numbers may up to 50 million, maybe 30 million
insects
• Inverts 70% of known & may be 90% of existing
species
• Most in tropics, coral reefs
• Incredible diversity – ocean cold and thermal
vents
– prokaryotes, invertebrates
Extinction is Forever
• Through natural extintion, at least 99% of
all species have become extinct
• So, why worry???
Natural Extinction
• Natural evolution - “genes” may remain from
evolutionary predecessors
• Mass extinction: end of reptile age (over 1/2
of all animals extinct)
– Open niches provide opportunities for speciation
through adaptive radiation
• Background extinction rate perhaps one
species per decade in undisturbed ecosystem
Human Caused Extinction
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Rate far, far exceeds background extinction rate
Extinction is genetic dead end
Speciation will not follow – niches destroyed
After mass extinctions – over 5 million years for
species diversity to recover!
– “Humans” on earth at best 3 ½ million years
• What will be the effect of loss of biodiversity on
the human species?
Human Activities and Biodiversity
• Degradation of 40-50% terrestrial ecosystems (see next
slide) - #1 cause is agriculture
• Wetlands – ½ lost since about 1900
• Global forest cover – reduced 20-50%
• Coral reefs at least 27% severely damaged, 70% damages
• Current global extinction between at least 100, probably
1000 to 10,000 times as before human impacted
environment
• At least 20-30% of current species in danger of premature
extinction
Arctic
Circle
Tropic of
Cancer
Equator
Tropic of
Capricorn
Human disturbance
Predominantly natural
Partially disturbed
Human dominated
Antarctic
Circle
Figure 1-5
Page 7
Biome
% of Area Disturbed
Temperate broadleaf forests
94%
Temperate evergreen forests
94%
Temperate grasslands
72%
Mixed mountain systems
71%
Tropical dry forests
70%
Subtropical and temperate
rain forests
67%
Cold deserts and semideserts
55%
Mixed island systems
53%
Warm deserts and
semideserts
44%
Tropical humid forests
37%
Tropical grasslands
26%
Temperate boreal forests
Tundra
18%
0.7%
Figure 22-14
Page 574
1%
Probably extinct
7%
Critically
imperiled
67%
Secure or
apparently
secure
8%
Imperiled
16%
Vulnerable
1%
Other
Figure 22-3
Page 562
Food supply
and demand
Changes in
water supply and
temperature
CO2, CH4,
N2O emissions
Water use and pollution
and soil nutrient loss
Freshwater
supply and
demand
Water availability
Deforestation
Changes in
precipitation
and temperature
Erosion,
pollution, and
changes in
water flow
Habitat change
and fragmentation
of habitat
Climate change
Forest product
supply and
demand
CO2 emission
Changes in
transpiration
and albedo
Habitat
change
Loss
of crop
genetic
diversity
Loss and
fragmentation
of habitat
Biodiversity loss
Figure 22-2
Page 561
Loss and
fragmentation
of habitat
Reduced
resistance
to change
So, What’s the Big Deal (22-3)
• Instrumental vs. Intrinsic value
– Instrumental- utilitarian
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Can we place a price tag? (pg 571 Spotlight)
Medicines
Crops originally wild – genetic diversity
Antibiotics
Microbes – cleanup, genes, etc.
Ecological services (4-34 – next slide)
Recreation and ecotourism
– Nonutilitarian
• Existence
• Aesthetic
• Intrinsic – life, ecosystems have inherent “right” to survive
Benefits of Biodiversity
• Food– especially genetic “bank” to improve domestic
crops
– many potentially valuable food plants
• Drugs and medicine - studying native
cultures
• Ecological benefits
• Aesthetic and cultural benefits
Solar
Capital
Water
resources
and
purification
Air
resources
and
purification
Climate
control
Recycling
vital
chemicals
Renewable
energy
resources
Soil
formation
and
renewal
Natural
Capital
Waste
removal and
detoxification
Natural
pest and
disease
control
Biodiversity
and gene
pool
Nonrenewable
energy
resources
Nonrenewable
mineral
resources
Potentially
renewable
matter
resources
Figure 4-34
Page 92
“Canaries in the Coal Mine” ??
• Read Why are amphibians vanishing? (pg
171)
• Read The plight of migrating birds (pg. 575)
Figure 22-15
Page 574
Cerulean warbler
Florida scrub jay
Sprague’s pipit
Bichnell’s thrush
California gnatcatcher Kirtland’s warbler
Blacked-capped vireo
Golden-cheeked
warbler
Henslow’s sparrow
Bachman’s warbler
Habitat loss #1
Cause of Biodiversity Loss
• Temperate biomes most affected to this
point
• Agriculture, development, water development are
top 3 in North America
• Habitat fragmentation
• No longer genetically or reproductively viable
• Increased “edge” where environment much different
than “interior” of a habitat
Habitat Alteration
• Pollution
• Global climate change
– Polar bear
Exotic Species Introduction
#2 Cause of Biodiversity Loss
• Plants:
– Purple loosestrife, honeysuckle, multifloral rose, kudzu vine
• Plant diseases- many crop
– Forest in PA- Dutch elm disease, American chestnut blight
• Terrestrial animals
– Pigeons, starlings, European sparrow, Norway rat
– Insects: gypsy moth, Japanese beetle, stink bug fire ant, Formosan
termite
• Aquatic animals
– Zebra mussels, sea lamprey
• Feral animals - cats and dogs; European pigs (southern
U.S.)
Threats of Biodiversity
Introduced Species
• Exotic species introduction
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Plants: Purple loosestrife, honeysuckle, multifloral rose
Zebra mussels
Canada Goose
Red Eared Slider
Feral animals - cats and dogs
• Diseases-American chestnut blight, Dutch elm
disease, and Hemlock Wooly Adelgid
• Insects: Asian long-horned beetle, Stink Bugs
Figure 22-17 (2)
Page 576
Sea lamprey
(attached to lake trout)
Argentina fire ant
Brown tree snake
Eurasian muffle
Common pigeon
(Rock dove)
Formosan termite
Zebra mussel
Asian long-horned
beetle
Asian tiger mosquito
Gypsy moth larvae
Exotic and Introduced Species
Figure 22-17 (1)
Page 576
Purple looselife
European starling
African honeybee
(“Killer bee”)
Marine toad
Water hyacinth
Japanese beetle
Nutria
Salt cedar
(Tamarisk)
Hydrilla
European wild boar
(Feral pig)
Exploitation – direct killing (read 22-6)
• Fishing- overharvesting
– Great Whales
• Market hunting, subsistence hunting
– American passenger pigeon, great whales, buffalo
– Many island species
– Poaching – over $8 billion per year
• Gorillas, pandas, large cats, rhinos, elephants
• Predator “control” –
– Wolves, coyotes, eagles
• Exotic pet trade
– Orchids, cacti, parrots, macaws, marine tropical fish
Figure 22-23
Page 584
PA Endangered Species
• Fish, Reptiles, and Amphibians
– PA Fish and Boat Commission
• Birds and mammals –
– PA Game Commission
• Wildlife Management Success Stories
Wildlife Management
Once PA Extirpated – Welcome
Back
Protecting Biodiversity
• Wildlife Management
– Hunting and fishing laws
– Habitat protection and enhancement
• Laws
– Lacey Act of 1900 – prevented commercial market hunting of
wild animals
– Endangered Species Act-1973 (583)
– CITES (582)
– Marine Mammal Protection Act
• Habitat protection- parks and refugees
• Zoos and botanical preserves
• Captive breeding and release programs – peregrines, Cal.
Condors, many endangered fish – sturgeon in PA
• Capture and release programs – eagles, wolves, sea and
river otters
Endangered Species Act
• Classifications
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Endangered
Threatened
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Vulnerable
• Agencies –
– National Marine Fisheries Services
– U.S. Fish and Wildlife Service
– PA State Agencies
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PA Fish and Boat Commission
PA Game Commission
PA Department of Forestry
PA DCNR
• Regulates
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Taking in any form (READ “The Regulatory Takings Controversy” on page 725)
Habitat protection
Harassment or interference during breeding
Federal agencies – nothing that jeopardizes endangered species
ESA - Numbers and
Classification
• Regulates “taking” in any form
– Read “The regulatory takings controversy” page 725
• 1250 listed - endangered & threatened species
• Nature Conservancy – say 30,000 should be
• Hundreds of species “warranted but precluded” from
protection - just no staff or dollars
• Federal budget 2002- $126 million (1/3 cost of one C-17
transport, $.44 per year per citizen)
• Where should money be spent?
– Habitat protection vs. a few “poster” species?
– Identify and protect keystone species
– Species “bias”
• Vertebrates: 91%
• Invertebrates: 75% or more of U.S. species, yet only 9% of listed species
Recovery Plans
• Fish and Wildlife Service
– $150 M per year, 1/2 on 10 species
– $5 M for 137 inverts/532 plants
– 25% no recovery plan
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Successes: peregrine, bald eagle, alligator
Controversy: snail darter and Tellico dam
Controversy: spotted owl
Controversy: reintroduction of Yellowstone
wolves
Minimum Viable Populations
• Small populations - below often difficult to
determine critical level- face extinction
• Island biogeography-small islands, fewer
species
• Problem: genetic inbreeding
• Demographic bottleneck:
– population in limited habitat-natural
catastrophe-remainder very genetic diversity
Zoos and “Seaworlds”
• Controversy
– “reservation and public education - or another
expression of human dominance?
• Exposure of people to wild animals
• Who do we protect - only the “human
defined” as beautiful and interesting?
• Breeding programs - reduce genetic
inbreeding- peregrine falcon as example
Ecotourism
Sustaining Terrestrial
Biodiversity
Chapters 23
Summary of Text Sections
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Land use - U.S. and world (595-596)
Managing forests (598-600)
What is happening to forests (604-608)
U.S. forest resources (609)
Tropical Deforestation (612-619)
Managing parks (619-621)
Wilderness (627)
Ecological restoration - (628-629)
The Wolf Controversy (594)
• 1973 - around 500 in loser 48
• Why over 2 million shot between 1850 and
1900?
• USFWS reintroduction 1987
• Who protested this reintroduction?
• How does NPS and Defenders of Wildlife
deal with upset ranchers?
Land Use in the World
Fig. 23-2
p. 595
Land Use in the United States
Rangeland
and pasture
29%
Fig. 23-3 p. 595
Types of US Public Lands
 Multiple-use lands:
National Forests
BLM
National Forest Service in Dept of Agr.
 Moderately-restricted use lands:
National Wildlife Refuges - USFWS
 Restricted-use lands:
National Park System- Dept of Interior
National Wilderness Preservation System
 Wilderness Act of 1964 (pg 627)
US Public Lands
Fig. 23-4
p. 596
Wildlife Refuges
• Teddy Roosevelt - 1901
• 511 in the system
• Hunting not only allowed, but in many have
become number one activity
Land Use In PA
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Pennsylvania Land Area 28,863,000 acres
Forested (Public and Private)
20,078,000 acres
State Forest Land 2,100,000 acres
State Forest Wild Areas 145,000 acres
Protected Natural Areas 79,000 acres
Even if we protect all 145,000 acres of state forest wild
areas, only a fraction of Pennsylvania - less than 1% - will
be left wild and protected for future generations to enjoy.
Forest Structure
Vertical Stratification in
the deciduous forest
Fig. 23-9 p. 601
Controversies: How to Use
Public Lands
• Livestock and U.S. public rangeland
– 2% of cattle and 10% of sheep on BLM land
– relatively low costs for grazing fees
• Logging (510)
– old growth forests - how much should be cut
– Forest Service loses money - subsidy to forest
companies
– Road construction - big issue in wilderness
areas
What is happening to world’s
forests (604)
• Reduced by 50% over past 8000 years,
much since 1970
• Rapidly degraded faster than sustainable
yield, especially tropical areas
• About 12% protected, much “only on
paper”
Virgin forests, 1620
Figure 23-18 (1)
Page 609
Virgin forests, 1998
Figure 23-18 (2)
Page 609
Greater than
0.5% decrease
Figure 23-15
Page 605
Greater than
0.5% net
increase
Pathogens and Insects
Fungal Diseases
 Chestnut blight
 Dutch elm disease
Insect Pests
 Bark beetles
Am Chestnut
Native Range
and Fungus
Forests and Fire
• Fire adapted ecosystems (607)
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savanna
temperate grasslands
southern pine forests
sequoia forests
• Why is fire needed for these ecosystems?
• Contrast surface fire and crown fire.
Smokey the Bear - A menace to
our forests?? (608)
• Protection against fires
• Did Smokey convince public that all firest are
bad?
• Current policy on many national lands in west,
Everglades:
– prescribed burns
– allow non-threatening fires to burn
• Controversies: Los Alamos(2000) and
Yellowstone (1988)
Fire
 Surface fires
PA Fires
 Crown fires
Fig. 23-17 p. 607
U.S. Forests resources (609)
• Lumber, grazing, minerals and oil
• Ecological: habitats, pollinator species,
water purification, aesthetic, recreation
• “Protected” today: about 40% of nation’s
forests
Biome
% of Area Disturbed
Temperate broadleaf forests
94%
Temperate evergreen forests
94%
Temperate grasslands
72%
Mixed mountain systems
71%
Tropical dry forests
70%
Subtropical and temperate
rain forests
67%
Cold deserts and semideserts
55%
Mixed island systems
53%
Warm deserts and
semideserts
44%
Tropical humid forests
37%
Tropical grasslands
26%
Temperate boreal forests
Tundra
18%
0.7%
Figure 22-14
Page 574
Tropical Forests
• Where: equatorial Africa (Congo), SA
(Amazon), CA, and Asia (Fig 23-6)
• About ½ already gone
• Rapidly being depleted (at this rate Amazon
gone in about 50 years)
Causes
Tropical Deforestation
• Population growth and poverty
– Fuelwood
• Commercial logging
– Logging roads beginning of downward spiral
• Clearing for cash crops – coffee, bananas,
sugarcane
• Clearing for ranching
• Unstainable small-scale farming
• Mining
Degradation of Tropical Forests
Fig. 23-22
p. 615
Instrumental Values of Tropical Forest
Ecosystems
Nonuse Values
Use Values
Direct Use Values
Timber and other
building materials
Fuelwood
Medicinal plants
Edible wild fruits
and plants
Fiber
Indirect Use
Values
Option Values
Future products:
Soil fertility
Medicines
Existence Values
Protection of
biological
diversity
Flood control
Water purification
Pollution control
Recreation and
tourism
Education
Ecological
services (pest
control,
pollination)
Genetic
information
Genetic
resources
Biological
insights
Food sources
Building
supplies
Future ecological
services
Maintaining
cultures of local
people
Continuing
ecological and
evolutionary
processes
Figure 23-20
Page 613
The Fuelwood Crisis (617)
 Planting fast-growing fuelwood plants
 Burning wood more efficiently
Scarcity of Fuelwood
Fig. 23-25 p. 618
Reducing Tropical Deforestation
(616-619 and Figure 23-23, page 617))
 Identification of ecological “hot spots) fig 23-29
 Reducing poverty and population growth
 Sustainable tropical agriculture –
Eg-buy coffee from, avoiding MN corporations
 Encourage protection of large tracts
 Debt-for-nature swaps
 Less destructive harvesting methods
Prevention
Protect most diverse and
endangered areas
Educate settlers about sustainable
agriculture and forestry
Phase out subsidies that encourage
unsustainable forest use
Add subsidies that encourage
sustainable forest use
Restoration
Reforestation
Rehabilitation
of degraded
areas
Concentrate
farming and
ranching on
already-cleared
areas
Protect forests with debt-for-nature
swaps, conservation easements,
and conservation concessions
Certify sustainably grown timber
Reduce illegal cutting
Reduce poverty
Slow population growth
Figure 23-23
Page 617
US National Parks
• The First: Yellowstone in 1872
• Yosemite: thanks to John Muir
• Why a national park - what are the
purposes?
Managing and Sustaining National Parks
 Most parks are too small to maintain
biodiversity – must protect surrounding
biogeographical areas
 Invasion by exotic species
 Popularity a major problem
What about concessionaires?
Traffic jams and air pollution – use shuttle
busses
 Better pay for park staff – much time now
acting as law enforcement
Sustaining Aquatic Ecosystems
Chapter 24
Importance of Aquatic Biological
Diversity (635)
• Ecological
• Economic
Earth’s Marine Diversity (635)
• Greatest –
– Coral reefs (fig 7-16)
– Deep ocean floor (fig 8-4)
• Top level predators often keystone species
• Pelagic usually least diverse
Marine Habitat Loss (638)
• Marine wetlands in lower 48 – 53% loss,
mostly agriculture
• Coral reefs: 60% threatened; 25% gone
• 35% Mangroves disappeared
– Check out importance of mangroves, page 149
Freshwater Loss and Degradation
(638)
• 60% rivers fragmented by dams, levees,
diversions, canals
• 44% of marine pollution comes from runoff
from developed coastal areas and rivers
Protecting Marine Biodiversity
• Big problem – think of tragedy of commons
(reread Connections, page 11)
• International agreements difficult to monitor and
enforce
• Coastal development, land pollution extensive to
most productive coastal ecosystems
• Marine sanctuaries can play critical role (646)
Overfishing (639)
• Sustaining fisheries (649)
• Management of fisheries (650-651)
• Management goal – optimum sustainable
yield
– Precautionary principle – page 649
Global Warming (639)
• Alter migration
• Damage coral reefs as ocean’s temperatures
and levels rise
• Coastal wetlands, mangroves threatened
•
Sea Turtles
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Why endangered??
Shrimp nets – turtle exclusion devices
Protect nesting coast habitats
Capture (gather eggs) and release programs
Other protections
– Endangered Species Act
– 1995 International Convention on Biological
Diversity
Commercial Whaling (640-646)
• Classic pattern of Tragedy of Commons
• IWC – 1946
– 1986 – end to commercial whaling
– Japan and Norway continue to hunt some species
• Other protections
– CITES (1975) for endangered whales
– Marine Mammal Protection Act – in U.S. waters
– 1995 International Convention on Biological Diversity
So, FILL the stinking swamp!
Loss Of Wetlands
• About 55% of original remain in lower 48
Restoration Ecology
Repair or reconstruct ecosystems
• Rehabilitation – “repair” specific aspects of
ecosystem – Chesapeake Bay, Everglades
• Remediation – remove chemicals – by physical or
biological means
• Reclamation or restoration– very large scale
restoration of severely degraded sites
– Everglades
• Mitigation- recreation of a destroyed ecosystem
Flood and Flood Control
• What Causes Floods – RAIN, of course!
– THINK AGAIN
Wetlands destruction
Loss of riparian habitats
Loss of floodplains
Levees
Channelization
Wetlands – Values, Preservation, and
Restoration
• Definition
– Hydric soils
– Wetland plant associations (eg, cattails, rushes)
– High water table much of year
• Types of Wetlands - Look at this webpage
– Review on page 160, 162
– Coastal wetlands
• Values in Nature - nonutilitarian and intrinsic
• Utilitarian -flood control, breeding habitats,
absorb nutrients and chemicals, very high
biodiversity, groundwater recharge
Wetlands – Preservation, and
Restoration – page 651
• U.S.: federal permit from Corps of
Engineers required to fill if over 3 acres
– Goal is zero wetland loss
– Section 404 of Clean Water Act
• Mitigation
– Controversy
• Restoration of damaged wetlands
Case Study: Florida Everglades
Read and study 652 to 653
• Why and important ecosystem?
• What has destroyed much of this
ecosystem?
• Everglades N.P. – 1947
– Did this preserve ecosystem and species??
• Restoration – began 2000
– What is being done?
Protecting and Restoring Lakes and
Rivers
• Threats to lakes and rivers (review these on
pages 654 to 657)
• Wild and Scenic Rivers (657)