Download Forests, Natural Parks, and Sustainability

Forests, Natural Parks,
and Sustainability
Managing Our Natural
Resources
World Land Use
Forest Distribution Map
National Forests and
Grasslands in United States
Types of Forest
Tropical Forest:
50% of world’s forests
Deforestation depletes
soils of nutrients
Rosy periwinkle: from
Madagascar,
produces vinblastine
(treat childhood
leukemia) &
vincristine (treat
Hodgkins’ Disease)
Boreal Forest:
25% of world’s
forests
Sphagnum mosses:
plant is antiseptic
(used as wound
dressing in WWI) &
tar from decaying
moss is used to treat
eczema & psoriasis
Temperate Forest:
25% of world’s forests
Ginseng is used as a
normalizer (high &
low blood pressure),
energizer (helps with
fatigue), & stress
reducer. Endangered
species.
Old Growth Forests: 36%
of total forests
1.
Old growth forests (sometimes called "ancient" forests)
have not been logged for at least 200 years.
They contain a variety of different tree species of
varying ages, including some very large trees that are
hundreds, or even thousands of years old.
Most important feature of an old growth forest is its
resilience.
2.
3.

Recover quickly from fires and windstorms because of the
variety (in age & species) of plants and wildlife
Old Growth Forest Loss from
1620 to 1990
*** Alaska contains the
most area of old growth
forests
Second Growth Forests: 60%
of total world forests
1. Second Growth Forest: A forest that has been regenerated
after the original trees in the area had been destroyed by
clear-cutting or forests fires.
2. Results from secondary succession
Commercial Forest
1. Managed forest containing only
1 or 2 tree species that are the
same age
2. Usually harvested by clear
cutting as soon as trees become
commercially valuable
3. Land is replanted and clear cut
again when trees are mature
4. Some commercial forests are
tree plantations that produce
foods such as bananas, olives,
citrus, etc
5. All commercial forests and tree
plantations lack biodiversity and
are susceptible to disease
Hybrid Popular trees
Olive tree plantation in Spain
Advantages and Disadvantages
of Commercial Forests
Advantages
 Can provide wood at fast
rate if managed correctly
 Reduces reliance on old
growth forest
Disadvantages
 Grow only 1 or 2 species of
trees; low biodiversity &
subjected to disease or
pest
 Less sustainable to
maintain than old growth
forests
 Cycles of cutting and
planting reduces soil
fertility
 Genetically engineered
seeds could spread to
other habitats
Ecosystem Services of Forests
1. Removes and sequesters
CO2 from atmosphere
2. Stabilizes average
atmospheric temps (b/c
CO2 has been removed)
3. Provides O2
4. Holds soil in place
5. Aids in aquifer recharge
6. Aids in flood control
7. Provides habitat for 2/3 of
terrestrial species
World-wide Major Uses of Wood
1. Biofuels: use wood for
cooking and heating
 Wood is converted into
charcoal; no very
efficient
 Cause of deforestation
in poor countries like
Libya
 Less than 1% of
Liberians have access
to modern fuels
Collecting wood from rubber trees
2. Industrial wood: used
to make lumber and
paper
Making charcoal
Solutions to Fuel-Wood Problems
1.
2.
3.
4.
Establish small plantations of
fast growing fuel-wood trees
and shrubs
Burn wood more efficiently;
provide cheap, more efficient,
less polluting wood burning
stoves
Provide methane burning
stoves (provide method of
obtaining methane from crop
and animal waste)
Provide solar ovens
Solar oven
Reducing Deforestation
1. Set aside & protect large areas
from deforestation & degradation
 Laws are easy to make but hard to
enforce
2. Consumers could reduce demand
for products that encourages
unsustainable logging in tropical
countries
 Educate people about the products
they use and where they are obtained
3. Reduce throw away paper products
 Throw away paper products are
cheaper than human labor that has to
wash dishes
How much of this trash could
be recycled?
Logging Roads Harms Ecosystems
1. Unpaved roads
 Increase soil erosion (by
wind and water)
 Increase sediment runoff
during rain storms
 Fragments habitats
 Increases exposure to
non-native / invasive
species (pests & disease)
& wildlife
 Opens areas for miners,
ranchers, hunters, & off
road vehicles
Logging Road in East
Kalimantan, Indonesia
Tree Harvesting Methods
** Leads to habitat
fragmentation!
Clear Cutting
Removing all the trees in
an area at one time
regardless of size or age
Advantage: most cost
effective
Disadvantage: prone to
soil & nutrient erosion into
nearby water sources
Replanted in monoculture
species
** Most sustainable
method of harvesting
Selective Cutting
Removing intermediate
or mature trees singly
or in small groups
Advantage: Most
sustainable method
Disadvantage: most
expensive
Strip Cutting
Clear cut a group of
along the contour of
the land; narrow
enough for natural
forest regeneration
Disadvantage: narrow
patches exposed for
soil erosion
1. Habitat Fragmentation:
involves alteration of
habitat resulting in spatial
separation of habitat units
from a previous state of
greater continuity
2. Caused by:
 Road building
 Housing development
 Clear cutting a forest
3. In all cases, biodiversity is
reduced & puts
endangered species at
risk
Habitat
Fragmentation
Fires
Surface fire: a fire that moves
along the forest floor, but can
occur up to 1.3 meters high
 Considered to be the lowest
intensity fire
 Consumes down wood,
shrubs and small seedlings
but does not necessarily
pose a threat to surrounding
areas.
Crown fire: a fire that starts to
reach the tops of trees
 Kills the majority of the tress
throughout the area
 Dangerous fires and can
spread the fastest.
 Can start out as surface fires
and spread to the crown
 Can jump from crown to
crown
Benefits of
Forest Fires
1.Forest fires are actually necessary to keep the forest
healthy and growing
 build-up of vegetation can prevent seeds from germinating and
stop the growth of new trees
 Opens forest floor to sunlight and enriches the soil
 Reduced competition allows established trees to grow stronger &
healthier
 Kills insects and disease pests
 Some tree species have fire resistant cones and need heat to
open seeds for germination
 Chaparral plants like scrub oak have leaves that are covered with
flammable resins; ensures a fire will occur so seeds can germinate
Reducing the Impact of
Disease and Pests on Trees
1. Ban imported lumber that
may carry new diseases
and pests
2. Remove / clear cut
infected and infested trees
3. Develop genetically
resistant species
4. Control pests with
conventional pesticides
Pitch canker; fungal disease
Kenaf
Kenaf: 6 months of growth
1. Kenaf: a fiber plant native to east central Africa where it
has been grown for food & fiber for several thousand
years



Fibers are brighter and stronger than wood fibers
Less environmental impact; does not require pesticides
Takes 20% less energy to produce kenaf fibers than wood fibers
National Parks in the United States
Fast fact:
The US was
the first
country to
establish a
National Park
System
Environmental Threats to National
Parks
1. Too small to support large animal species
2. Invasions of non-native species
3. Less developed nations have laws but no way to
enforce them
 People enter illegally and take wood, game animals
 Loggers and miners operate illegally
 Poachers kill and sell endangered animals (tigers,
elephants, etc)
Major Threats to National Parks in
United States
1.
Too many visitors



2.
3.
4.
Leave trash
Walk off the trails (sometimes
damaging endangered species)
Take “free souvenirs”
Dirt bikes and ATV tear up trails
Jet skis snow mobiles degrade
aesthetics
Damage by accidentally or
intentionally introduced species
Trash left behind in a park
Don’t take anything out of
the parks, but pictures!
The Nature Conservancy
1.
2.
3.
Group of professional ecologists
Created the largest system of privately held nature
reserves & wildlife sanctuaries in 30 countries & all 50
states
Goal: purchase and protect large areas of land & its
inhabitants
Wilderness Act
1.
2.
3.
4.
Wilderness: land officially designated as an area where
natural communities have not seriously been disturbed by
humans & where human activities are limited by law.
Passed in 1964
Allowed government to protect undeveloped tracts of
public land from development as part of the National
Wilderness Preservation System
Land gets the highest level of protection from human
activities (logging, mining, ATV, etc)
What Drove Teddy Roosevelt
Theodore Roosevelt, left,
poses with the conservationist
John Muir on Glacier Point in
Yosemite, California
1. Visited the badlands in September 1883 in hopes of big game hunting
 By the time he arrived, the last large herds of bison were gone due to
overhunting and disease
 Spend more time in the area & he became increasingly alarmed by the
damage that was being done to the land and its wildlife
 He witnessed the virtual destruction of some big game species.
 Overgrazing severely impacted the grasslands which also affected the
habitats of small mammals and songbirds.
2. Conservation increasingly became one of Roosevelt's main concerns.
Teddy Roosevelt
1. After he became President in
1901, Roosevelt used his authority
to protect wildlife and public lands
by creating the U.S. Forest Service
2. Established:







150 National Forests
51 Federal Bird Reserves
4 National Game Reserves
5 National Parks
18 National Monuments
24 Reclamation Projects
7 Conservation Conferences &
Commissions
3. "Conservationist President."
Teddy Roosevelt at Yosemite
in 1903
Categories of Public Lands
1. National Park: managed for
scientific, educational, &
recreational use
 Usually not logged or mined for
ore
2. National Forests: allows for
sustained use of biological,
mineral, and recreational
resources.
3. Nature Reserves and Wilderness
Areas: established to protect
species and ecosystems
 Buffer Zone: area that strictly protects the
inner core of a nature reserve
 Habitat corridor: located between nature
reserves; allows for the migration of
species that need a large range
Buffer zone shown by
dashed lines
Ecological Services of
Grasslands
1.
2.
3.
4.
Soil formation (slow decay of leaf litter)
Control soil erosion (roots hold soil in place)
Chemical cycling (nitrogen cycle)
Storage of atmospheric CO2 (carbon sink in
plants)
5. Maintains biodiversity
Rangelands
Rangelands
1. Unfenced grasslands in temperate and tropical
regions (26% of world’s land surface)
2. Supply vegetation for grazing and browsing
3. Animals raised include sheep, goats, and
cattle
4. Carrying capacity of rangeland depends on
what you are raising and the type of vegetation

Biggest threat to rangelands is OVERGRAZING
Overgrazing
1. Overgrazing: grazing too many
livestock for too long a period on
land unable to recover its vegetation
 Overgrazing exceeds the carrying
capacity of a pasture
2. Grazing lands are often nutritionally
marginal, close to or in arid regions
 Overgrazing removes this protective
vegetation, while livestock hooves
trample exposed soils.
 Soil is prone to wind and water
erosion
 Once exposed and impacted, the
soils can no longer support
vegetation growth, thus they become
desert-like or barren (desertification)
About one third of the world's
range is threatened by
overgrazing.
Malpai Borderlands
1. One of the most biologically diverse
areas in North America
2. How fire helped to maintain this
ecosystem:
 Burned away mesquite & other invasive
shrubs that require a lot of H2O
 Kept land open for native grasses
3. Ranchers suppressed fires:
 Ranchers allowed overgrazing
 Ranchers suppressed fires & kept
grassland from burning
 Trees & shrubs replaced grasses, soil
badly eroded
Located just north of NA &
Mexico border
Sustainably Managing Rangelands
1. Control number of grazing animals & duration of
grazing in a particular area to keep from
exceeding the carrying capacity
2. Move livestock to different places from time to
time (rotate grazing areas)
Tragedy of the Commons
1. A Common: Anything that is not owned by one
specific entity but is used by all




Forest
Grassland
Sea
Air
2. If the Common is misused by any one group of
people and the Common becomes deteriorated,
then it may put the Common in jeopardy for
EVERYONE!
3. EX: overfishing, overgrazing, clear-cutting a
forest, air pollution