Sustaining Wild &

Terrestrial Species

Chapter 22 Sustaining Wild Species• Biodiversity• Estimate 12-14 million species• Endangered species • Threatened/vulnerable species • Increase Biodiversity:• physically diverse habitat• moderate environmental

disturbance• small variations in environmental

conditions (nutrient supply, precipitation, and temperature)

• middle stages of succession• evolution• Decrease Biodiversity: • environmental stress• large environmental disturbance• extreme environmental conditions• limit of an essential nutrient,

habitat or other resource• introduce nonnative species• geographic isolation• human activities

http://www.fws.gov/Endangered/wildlife.htmlEndangered vs Threatened

Human Impact

• What is the Human Impact on Biodiversity?• increasing fragmentation, habitat loss, degradation ***greatest

threat to species• eliminating wetlands• use/waste/destroy – net primary productivity of ecosystems• logging• land conversion (agriculture, commercial development)• destruction of coral reefs• simplifying many diverse ecosystems (because of development)

and preventing speciation (“speciation crisis”)• increase speciation of opportunist species (insects/weeds) when

we degrade land• decrease level of higher order organisms – mammals and trees• pollution, use of pesticides, and climate change

Human Impacts on BiodiversityHuman Impacts on Biodiversity

Fig. 22-2 p. 561

Species Extinction:

• Local – species no longer in particular area

• Ecological – species are so few no longer play role in ecological community

• Biological – species no longer found “forever”

• # and diversity of species – balance between speciation and extinction

• Biodiversity = Speciation - Extinction• 99.9% of all species that existed – now

extinct (by evolution)• Extinction spasms – large # lost over

a few centuries to 1000 years• Use models of species vs area “loss of

habitat (90%)→causes loss of species (50%)

• Current rate of extinction between .1% - 1% per year (not sure)

• Still exponential compared to before humans existed (.0001%)

• extinction rates higher when biodiversity rich Ex-tropical rainforests, coral reefs

Extinct Organisms

Passenger pigeon

Great auk Dodo Dusky seaside sparrow

Aepyornis(Madagascar)

• Extinction occurs from• habitat loss• nonnative species• hunting and poaching

Type of Nonnative Organism Annual Losses and DamagesCrop disease

Crop weeds

Rats

Feral cats and outdoor pet cats

Crop insects

Livestock diseases

Forest insects and diseases

Zebra mussels

Common pigeon

Formosan termite

Fishes

Asian clam

Feral pigs

Starlings

Fire ant

$23.5 billion

$23.4 billion

$19 billion

$17 billion

$14 billion

$9 billion

$4.8 billion

$3 billion

$1.1 billion

$1.1 billion

$1.1 billion

$1.1 billion

$0.8 billion

$0.8 billion

$0.6 billion

Figure 22-17 (1)Page 576

Purple looselife European starling African honeybee(“Killer bee”)

Nutria Salt cedar(Tamarisk)

Marine toad Water hyacinth Japanese beetle Hydrilla European wild boar(Feral pig)

Invasive Species

Figure 22-17 (2)Page 576

Sea lamprey(attached to lake trout)

Argentina fire ant Eurasian muffleBrown tree snake Common pigeon(Rock dove)

Formosan termite Zebra mussel Asian long-hornedbeetle

Asian tiger mosquito Gypsy moth larvae

Invasive Species Continued Streaming Facts on FileInvasive Species

What does biodiversity do for us?

• food• fuel• lumber, paper• medicine (for cancers –

alkaloids)• exploration of new

pharmaceuticals• genetic engineering of new

products• pollination• nutrient cycles• pest control• climate regulation• water• waste decomposition• purification of air and water• allow for evolution• recreation “ecotourism”• “biophilia” (love of life)

Solutions• Bioinformatics – communicating biological

information• Ex - via internet• Ex – “Species 2000”• lists all species for study• CITES – Convention on International Trade in

Endangered Species (1975)• now signed by 152 countries• protects endangered or threatened wild

species• 2 US Laws:• Lacey Act of 1990 – prohibits transporting

wild animals across state’s border without a permit

• Endangered Species Act of 1973 (ESA) – amended in 1982-1988

• illegal for Americans to import or trade any product made from endangered or threatened species (unless used for science)

• need to protect critical habitat• laws hard to enforce, little fines given • Wildlife Management• Sanctuaries/Refuges/Zoos/Aquariums

Ch 23 Sustaining Terrestrial Biodiversity

• Forest Classification• Tropical (47%)• Subtropical (9%), • Temperate (11%)• Boreal (Polar) 33%

• Layers of a Tree• Emergent – birds and bats• Canopy – birds and reptiles• Understory – shady plants,

birds, squirrels• Floor – insects, bacteria• Subsoil – nematodes,

microorganisms

• Old growth forests (frontier)• around for several hundred

years• uncut forests/regenerated• lots of diversity• Second growth forests• secondary ecological succession• human activity (clear cutting for

timber or conversion to cropland)• natural forces (fire, hurricanes,

volcanoes) • Tree plantations/free farms• uniform trees of one species• harvested by clear-cutting• commercially valuable• produce 10% of world’s wood

• Forests provide many ecological and economic services:

• cycling• reduce soil erosion• absorb and release water• purify air and water• influence climate/reduce global

warming• store carbon• provide wildlife habitats• fuelwood (developing countries) • provides 7% of world’s energy

supply• (developing 15%, 3% developed)• lumber• pulp to make paper• mining• livestock grazing• recreation and jobs• prescription drugs• Paper Production• world’s fastest growing use of

wood (use pulpwood) • 50% packaging, 30% writing and

printing, 12% newspaper, 8% tissues/towels

Figure 23-7Page 600

Forests

Ecological Services

• Support energy flow and chemical cycling

• Reduce soil erosion • Absorb and release water

• Purify water

• Purify air

• Influence local and regional climate

• Store atmospheric carbon

• Provide numerous wildlife habitats

Economic Services

• Fuelwood

• Lumber

• Pulp to make paper

• Mining

• Livestock grazing

• Recreation

• Jobs

Land Use:

• urban use (2%), cropland (11%), desert (20%), wetlands, tundra (9%),pastures/rangeland (26%), forests (32% )

• Federal Public Lands vs Private Lands • 35% federal, 55% private, 7% state and

local, 3% native American (US)• 1)multiple use lands• used for all purposes• mining, logging, recreation, farming,

fishing, conservation• National Forest System – managed by

US Forest Service• 156 forests and 22 grasslands• Bureau of Land Management (BLM) –

manages National Resource lands in western states and Alaska

• 2)moderately restricted use lands• some permitted activities but regulated• regulate 524 National Wildlife Refuges• 3)restricted use lands• 55 major parks and 324 national

recreation areas (NPS-national park)• only camping, hiking, fishing, boating

Land Use in the WorldLand Use in the World

Fig. 23-2p. 595

Land Use in the United StatesLand Use in the United States

Fig. 23-3 p. 595Fig. 23-3 p. 595

Rangeland and pasture 29%

Management of US Public Lands

• Based on Aldo Leopold’s Concept of Land Ethics)

• need to conserve environment• humans need to be protectors

of nature• need to view land as a

community we belong to and love and respect (not as a commodity belonging to us).

• Economists/developers • more concerned about how

useful land is for resources• does it to help economic

growth

Forest management• Even aged management• trees same age and size• industrial forestry• tree plantation• fast growing• economically desirable• 6-100 years (depends on species)• Uneven aged management• longer term• many sizes and shapes• variety of tree species• biological diversity• long term production• quality lumber (if you want nicer

furniture)• selective cutting• multiple use of forest (timber as well

as wildlife, watershed protection, and recreation)

• fosters natural regeneration• Tropics – can be 6-10 year rotations• Temperate – 20-30 years rotations

Steps in Forest Management (rotation)

• take inventory of site• develop a forest

management plan• build roads into site• prepare sites for

harvest• harvest lumber• regenerate and

manage site until next harvest

Management Strategies

Fig. 23-11 p. 601Fig. 23-11 p. 601

Fig. 23-12 p. 602Fig. 23-12 p. 602

Tree Harvesting:• Selective cutting –

intermediate/mature trees in uneven-aged forest, cut individual or in small groups

• Shelterwood cutting – removes all mature trees in 2 or three cuttings, over 10 years

• Seed-tree cutting – harvests all in 1 cutting, leaves a few seed-producing trees to regenerate

• Clear-cutting – removes all trees from an area in a singe cutting

• Strip cutting – clear cutting of forest in narrow strips over several decades with minimal damage

Selective Cutting

Shelterwood Cutting

Cut 1

Cut 2

Clear-Cutting

Seed-Tree Cutting

Strip Cutting

Uncut Cut Cut Cut Uncut

6–10 years ago3–5 years ago 1 year ago

Impacts of Deforestation:

• reduces biodiversity• reduces uptake of

greenhouse gases CO2 • adds CO2 if trees burned

or allowed to decay (contributed 30% of buildup of CO2)

• affects precipitation → decline of rainfall

• increases soil erosion• accelerates floods by

removing tree cover

Degradation of Tropical Forests

Fig. 23-22p. 615

Outside Influences on Forests:

• 1)Disease • parasitic fungi→ • Chestnut blight • Dutch Elm Disease • White Pine Blister Rust • 2)Insects Ex – Beetles, moth,

larvae, worms• 3)Fires• Surface fire – removes bottom low-

lying vegetation and small trees• good when occasional• →secondary succession• Crown fire – more serious• larger trees/larger scale• →mass destruction• “Smokey Bear” – tries to prevent• 4)Air Pollution and Climate Change

(too warm/no rain/more fires)

Chestnut blight has eliminatedChestnut trees as a commercial tree. (no cure)

Surface Fire

Crown Fire

Fire

Surface firesSurface fires Crown firesCrown fires

Fig. 23-17 p. 607

Solutions• sustainable• grow more timber on long rotations• strip cutting/selective cutting instead

of clear cutting• minimize fragmentation• minimize erosion• reduce road building into uncut forest• leaving standing dead trees (snags)

and fallen timber (boles) to maintain wildlife habitats/recycled as nutrients

• switch to nonrenewable resources (ironic to say) Ex use steel/aluminum framing, carpeting

• genetically improved trees on tree plantations (that use less space)

• “debt for nature swap” – protect nature and we will give you foreign aid or debt relief

• “use tree-free” fibers – Ex Kenaf in US (rapidly growing woody annual plant, expensive, 3 times more expensive)

http://www.fscus.org/Florida Stewardship Council

National Parks• 1100 National Parks in World• US National Park System – established in 1912• 55 National Parks (most in west)• Parks/ Reserves should be placed in world’s most biodiverse

countries (rainforests) and at hot spots” - areas rich in plants and animals

• Nature Parks/Preserves (to protect biodiversity)• 1)Circular reserve better than rectangle? • YES - less edges• 2)Single large preserve vs several small reserves? • Large Preserve - Better to maintain large species/more species• Several Small Reserves - wider variety of habitats/more

biodiversity/ cannot be devastated)• 3)Homogeneous or heterogeneous reserve? • better to have heterogeneous because have a variety of habitat

patches -“patch dynamics” with different sizes, shapes, and successional stages

• 4)Should small reserves be connected or isolated?• should be connected by habitat corridors• helps support more species • allows for migration of animals if conditions unsuitable (like

global warming)• 5)Want Buffer zones (biosphere reserve) – inner core

surrounded by buffer zones

Biosphere Reserve

Core area

Buffer zone 1

Buffer zone 2

Human settlements

Tourism andeducation center

Research station

Want to always preserve wilderness

• US Wilderness Act of 1964

• Wilderness - areas of undeveloped land

• “man visits but does not remain”

• Should be at least 150 square miles

• 2002 Edward Wilson – big leader in biodiversity, book “Future of Life”