ES 7 - Restoration Ecology

Topic 7 – Restoration Ecology

Ecological restoration

- Reverse degradation and restore native ecosystem

- Restoration to an original pristine condition is rarely possible. Often it involves compromise between ideal goals and pragmatic achievable goals.

- Rehabilitation - repairing ecosystem function, but not to original condition (may be similar to the original community or an entirely different community)

- Reintroduction - transplanting organisms from an external source to a site where they have been previously reduced/eliminated

- Remediation - using chemical, physical, or biological methods to remove pollution while causing as little disruption as possible

- Reclamation - employs stronger, more extreme techniques to clean up severe pollution or create a newly functioning ecosystem on a seriously degraded or barren site

- Mitigation - compensation for destroying a site by purchasing or creating one of more or less equal ecological value somewhere else

- Restoration draws on principles from ecology, hydrology, chemistry and soil science

- Should we attempt to restore what used to be or create a community compatible with future conditions?

Similarities of Restoration Projects

- Removing physical stressors (i.e. the cause of degradation)

- Controlling invasive species

- Replanting

- Captive breeding and reestablishing fauna

o Example: Wolves returned to Yellowstone National Park

- Monitoring

Early Conservationist

- Gifford Pinchot - First head of the U.S. Forest Service. Pioneer in resource management. Promoted science-based management of trees as a commercial resource for logging.

- Aldo Leopold - pioneer in restoration ecology with theories of game management, conservation and land restoration. He wrote a land ethic stating that responsible land stewardship meant the land was capable of self renewal.

Resilience

- Sometimes stopping the damage is all that is necessary and Nature can rebuild.

- For example the forests in Vermont today are interconnected biological communities

o By 1840, early settlers had cleared the land and sheep farming dominated. Only 20% of forest remained.

o Today 80% of the land is forested. Much of the forest resembles old growth forest and moose, bear, pine martens and bobcats have become re-established.

o Vermont law requires consulting a professional forester and developing a plan before cutting forested areas.

Possible Need for Help

- Today, the Bermuda cahow is Bermuda’s national bird.

- This endemic bird was thought to be extinct by the mid 1600s due to human hunting and predation by hogs, cats, rats.

- In 1951, 18 nesting pairs were discovered.

- Protection program begun on Nonsuch Island, which involved removing invasive species, reintroducing native vegetation, creating nesting burrows, and protecting against predators.

- By 2002, there were 200 birds.

Restoration Benefit

- Logging companies reforest cut areas.

- Creates a monoculture that does not have the complexity of natural forest

- But does provide ground cover, habitat for some species, and lumber

- War torn Rwanda began a country-wide forest restoration in 2001.

- 85% of the population still subsists on farms on degraded land

- Restoration of forest conserves the national wildlife including the mountain gorilla.

- Tourists visit these areas for wildlife viewing

- Trees improve air quality and provide shade for cooling.

- Trees provide wildlife habitat

- United Nations billion tree initiative was inspired by Wangari Maathai’s Green Belt Movement in Kenya

Oak Savanna

- Forest with scattered open grown trees where the canopy covers 10% to 50% of the area and the ground has grasses and flowering plants.

- Most common tree is the fire-adapted bur oak.

- Oak savanna once covered area between Great Plains and the deciduous forest of the eastern U.S.

- Wisconsin had 2 million ha; less than 0.01% is left.

- Difficult to restore because it is maintained by fire

- Somme Prairie Grove in Cook County, Illinois is being restored.

Somme Prairie Grove Restoration

- Native species drop, natural area rating index (NARI) rises

Role of Fire

- Land managers now recognize fire as a key factor in maintaining/restoring many forest types.

- Can also allow natural fires to burn

- Superior National Forest in Minnesota has started a program of prescribed fires to maintain complex forest structure

- Periodic prescribed burns protect ancient sequoias in California

Restoring Prairies

- Before European settlement, the eastern edge of the Great Plains was covered by tallgrass prairie, with grasses reaching a height of 2 m (6 ft).

- Less than 2% remains

- The middle of the Great Plains contained a mixed prairie of bunch and sod-forming grasses.

- The western edge of the Great Plains, with less rainfall, was covered with shortgrass prairie containing bunch grasses 30 cm (1 ft) in height.

- These prairies were maintained by grazing and by fires.

- In 1934, Aldo Leopold began to re-create tallgrass prairie on an abandoned farm in Madison, Wisconsin (now the Curtis Prairie).

- Discovered that fire was essential. Kills weeds and removes soil nitrogen, which gives low-nitrogen native species an advantage.

- Nature Conservancy has tallgrass prairie northwest of Tulsa, Oklahoma

- 1/3 of each pasture burned per year

- Bison re-introduced

Shortgrass Prairie Preserved

- The middle of the Great Plains has been fertile cropland due to irrigation by water from the Ogallala aquifer. This water is being depleted and it may be impossible to continue our current mode of farming there.

- Human population is leaving these areas.

- Some believe the best use of the land is to return it to buffalo commons, allowing buffalo to graze freely.

- Saving shortgrass prairie in Montana

- Nature Conservancy bought the Matador ranch, but permits ranchers to use the land in exchange for agreements to protect prairie dogs and sage grouse, control weeds, and allow fire.

- American Prairie Foundation is buying land, pulling out fences, eliminating buildings and returning the land to wilderness. Plans to restore elk, bison, wolves and grizzly bears.

- Locals resent the reintroduction of predators and of outside funding

Wetland & Stream Restoration

- Wetlands and streams provide ecological services.

- Hydrologic cycle

- Food and habitat for a variety of species

- Coastal wetlands absorb storm surge

- Wetlands occupy less than 5% of land, but 1/3 of endangered species spend at least part of their life cycle there.

- Up until the 1970s, government gave incentives to drain and destroy wetlands.

- Clean Water Act (1972) began protecting streams and wetlands from pollution discharge.

- Farm Bill (1985) blocked agricultural subsidies to farmers who damaged wetlands.

- Many states now have a “no net loss” policy and wetlands are coming back.

- However, there is an imbalance as swamps are drained and replaced by small ponds. No net loss, but not the same ecosystems.

- Pokok paya bakau boleh didapati di kawasan seluas 586,036 hektar dengan 57 peratus di Sabah, 26 peratus di Sarawak dan 17 peratus di Semenanjung Malaysia.

- FRIM, UMT and numbers of

- organisation help to restore

- wetlands in Malaysia

- Artificial wetlands can be used to treat sewage and collect storm runoff.

- Wetland mitigation is required when development destroys a natural wetland, but it often does not replace native species and ecological functions.

- In building a housing project in Minnesota, the developer destroyed a complex native wetland containing rare orchids. The mitigation is just a hole filled with rainwater. It quickly became re-vegetated with invasive species.

Everglades Restoration

- Draining the Everglades resulted in water shortages in the dry season.

- Everglades National Park has lost 90% of its wading birds. Its ecosystem may be collapsing.

- Plans to remove levees, restore natural course of rivers, and save water in underground aquifers for later use (while still controlling flooding)

- Plan announced in 2000 is over budget and behind schedule

Chesapeake Bay

- America’s largest and richest estuary.

- 2,700 species spend all or part of their lives in/near the bay.

- It suffers from pollution and degraded water quality.

- Important species of fish and shellfish have declined dramatically.

- Eelgrass, a keystone species, was smothered by sediment. It served as a nursery for marine animals.

- Damage is due to

- overfishing

- sewage discharge

- silt from erosion

- heavy metals and toxic chemicals

- heat from industry

- pesticides and herbicides

- oil spills

Stream

- Streams threatened by pollution, toxins, invasive organisms, erosion and other insults

- 44% of streams suffer degradation, mostly due to sedimentation and excess nutrients.

- Streams have been turned into cement channels and buried underground in urban areas. Little resemblance to natural state.

- Rebuilding involves returning to a natural stream bed.

- Reduce sediment entering streams by providing ground cover

- Redirect water with

- earth-moving equipment

- barriers to deflect current

- Provide fish habitat with logs, roots, artificial “lunkers”

- Stabilize banks by having slope of no more than 45 degrees

Bioremediation

- using living organisms to remove toxins

o Some plants can selectively eliminate toxins from soil.

o Bacteria can remove toxins from water if they are provided with oxygen and nutrients.

- If the area is small, contaminated dirt can be hauled away and clean soil brought in.

- Decontaminated urban fields (“brown fields”) can become valuable real estate.

Reclamation

- Reclamation means the repairing of human-damaged lands.

- The Surface Mining Control and Reclamation Act requires mine operators to restore the shape of the land to its original contour and re-vegetate it to minimize impacts on local surface and groundwater

- More than 8000 square kilometers of former strip mines have been reclaimed.

- Some of the largest strip mines like the Berkely mine pit in Butte, Montana will never be fully reclaimed.

ES 6 - Global Population & Environment

Topic 6 – Global Population & Environment

Demography

-          Study of populations.

Human Demography

-          Study of human population size, structure, and interrelated variables (births, deaths, where they live)

Population Dynamics

-          (population growth and change) reveal principles which apply to all species, human and non-human.

Growth Limit

-          Thomas Malthus 1798 wrote “An essay on the principle of population”

-          He said that human populations tend to increase at exponential rate while food production either remains stable or increases only slowly

-          Eventually human populations will outstrip food supply and eventually collapse

-          Malthus also said that diseases or famines that kill people are positive checks on population growth.

-          Neo-Malthusians believe that we are approaching or surpassed Earth’s carrying capacity

-          They say that surplus population must be addressed directly by birth control

-          One neo-malthusian said that by 2100 12 b people would be suffering life on earth. He argues that the optimum population is 2 billion which will allow a high standard of living

Environmental Limits

-          Exponential growth cannot continue indefinitely

-          Eventually populations come up against environmental limits to further increase

-          Population increase until the carrying capacity is reached

-          At carrying capacity, population size is constant so birth rate must equal death rate and thus population growth is zero

-          The concept of carrying says that a given environment can only support a certain number of individuals of a particular species

-          For example for African buffalo, carrying capacity is largely determined by amount of grass available as food

-          For barnacles (teritip) on a rocky shore, carrying capacity is determined by availability of space on the rocks

Carrying Capacity

-          Maximum population size that can be sustained indefinitely

-          A population in excess of its carrying capacity damages the environment's ability to support that population.

-          The carrying capacity for humans must take into account the desired average standard of living.

Growth Limiting Factors

-          Limiting factors are those which limit population growth; they may be short-term (limiting growth within one year of occurrence), intermediate-term (limiting growth after one year but before 10 years of occurrence) or long-term (limiting growth ten or more years after occurrence).

-          Food supply is short-term limiting factor; pollution medium term; global climate change is long-term factor

Modern Birth Reduction Pressures

-          Higher education and personal freedom for women often result in decisions to limit childbearing

-          High cost of education in many countries make parents more likely to have only 1 or 2 children for whom they can concentrate their time, energy and financial resources

Total Fertility Rate

-          Total fertility rate (TFR) or expected number of children per woman per lifetime has an important time-lag effect on human population growth; a high TFR implies future population growth; a low TFR, population decline.

-          When a population has a TFR of approximately 2.0, it has reached replacement level fertility, indicating the population will achieve stability.

-          The delay between a population's achievement of replacement level fertility and its growth rate reaching zero is termed population momentum or lag effect.

-          Populations continue to grow after reaching replacement level fertility (i.e., display the lag effect) not because women are having many children each, but because there are so many women of childbearing age.

Population Control

-          Continued rapid population growth in many poor countries will markedly increase environmental stress ( on water, land degradation, overhunting and overfishing, falling farm size, deforestation, other habitat destruction) on the planet. Africa is a good example

-          High fertility rates in poor countries also result in the children suffering from underinvestment in education, health, nutrition. So fewer children means healthier children…

-          So it is beneficial to control fertility in poorer countries

Population Control Strategy (JD Sachs, UN Millennium Project 2007)

-          Four steps to quickly reduce fertility rates from 5 or more children per fertile woman to 3 or less within 10-15 years:

o   Promote child survival. Parents choose to have fewer children if they can expect their children to survive

o   Promote gender equality and education for girls

o   Promote family planning and availability of contraceptives

o   Raise productivity on farms

Population, Consumption, & Our Ecological Footprint

-          Ever-accelerating human consumption of natural resources lies at the root of many of our global environmental problems.

-          Current consumption patterns stress limited natural resources, contribute to global warming, and create wasteful and even toxic byproducts that affect the quality of life and the health of communities around the world.

-          Add global population growth to the mix, and it becomes increasingly clear how the health of the ecosystems we depend on for survival are being compromised.

People overpopulation

-          Too many people in a geographic area

Consumption overpopulation

-          Each individual of population consumes too large shares of resources

Fact: In 2006, industrial countries, with less than 20% of the world's population, contributed roughly 40 percent of global carbon emissions, and they are responsible for more than 60% of the total carbon dioxide that fossil fuel combustion has added to the atmosphere since the Industrial Revolution began. But this picture is now changing rapidly, particularly in China, where emissions are now rising at 10 percent a year--10 times the average rate in industrial nations. By 2006, China's fossil fuel emissions were only 12 percent below the United States--and gaining rapidly.

Ecological Footprint

-          An amount of productive land, fresh water, and ocean required on a continuous basis to supply that person with food, wood, energy, water, housing, clothing, transportation, and waste disposal. In the

Population, consumption, and environmental impact

-          Biologist Paul R. Ehrlich and physicist John P.

-          Holdren proposed the IPAT model in the 1970s. It shows the mathematical relationship between environmental impacts and the forces that drive them

-          This method of assessment is usually referred to as the IPAT equation:  I = P x A x T.

o   P = number of people

o   A = affluence per person (consumption / resources used)

o   T = environmental effects (resources / wastes of technologies)

IPAT Benefits

-          Identify what we don’t know or understand about consumption and its environmental impact.

-          Which kinds of consumption have the greatest destructive impact on the environment?

-          Which groups in society are responsible for the greatest environmental disruption?

-          How can we alter the activities of these environmentally disruptive groups?

Global Issues of Population & Ecological Footprints

-          Climate change, threatened ocean, desertification, deforestation

ES 5 - Wildlife Management

Topic 5 – Wildlife Management

Biodiversity loss and extinction

-          Biodiversity is a broad term describing the diversity (kepelbagaian) of genes, species, and ecosystems in a region

-          Extinction (kepupusan) is the death of a species, the elimination of all the individuals of a particular kind

-          Extinction is a natural and common event in the long history of biological evolution but the issue here is when extinction is the result of human domination of the Earth

-          Scientists recognize that species continually disappear at a background extinction rate estimated at about one species per million per year, -the current rate of extinction is 100 times the background rate. And more likely much higher

-          In the Americas, 73 percent of the large plant-eaters, along with the saber-toothed cat, were gone within 1,200 years after humans migrated to the continents about 13,600 years ago. Wiped out were animals like mammoths, camels, mastodons, large ground sloths and the glyptodont.

What do we lose when species become extinct?

-          We can put values to biodiversity based on ecological roles played by the organisms, financial value or based on ethical considerations

-          But biodiversity provides biological and ecosystem services (which seems for “free”):

o   Species depend on the diversity of organisms on Earth as all organisms are related to others for their needs. Food chains feed various organisms

o   Humans depend on plants and animals for their food, drugs and other products

o   Plants remove CO₂ and provide O₂.

Extinct Species - the Dodo

·         Discovered by Portuguese sailors (1598)

·         Indigenous to island of Mauritius

·         Isolated from human contact

·         Killed by humans and introduced species

·         Last one died in 1681

·         The animals (and pets)- dogs, cats, rats introduced by European settlers in Mauritius were the predators that devoured the eggs of the Dodo and possibly the adults as well. Previously there were no predators of the Dodo.

Hot Spots

-          most endangered habitats

-          Based on how much of the original habitat is left and the number of unique species present in the region. Most endangered are island ecosystems with unique species that are endemic.

-          Malaysia has 225 species that are considered threatened Critically Endangered, Endangered, or Vulnerable and 1 species already extinct (source: IUCN)

Extinction factors

-          Habitat loss

-          Human population growth

-          Hunting or overhunting and Poaching (illegal hunting of animals)

-          Overexploitation of resources

-          Introduced Species or “alien species” for e.g. introduction of rats (by accident) and rabbits (introduced by man) into Australia competed for grass for forage with Australia’s natural wildlife (kangaroo, birds and others).

-          Pollution due to human activities

Hetch Hetchy Valley

-          Some environmental battles involving the protection of national parks were lost. John Muir’s Sierra Club fought with the city of San Francisco over its efforts to dam a river and form a reservoir in the beautiful Hetch Hetchy Valley, which lay within Yosemite National Park. In 1913 Congress approved the dam. The State of California is considering restoring Hetch Hetchy, at an estimated cost as high as $10 billion.

Threats to Biodiversity
- 4 major human activities that threaten to reduce biodiversity

-          Habitat loss

o   Human activities convert natural ecosystems to human dominated systems. The result in change eliminate or reduce numbers of species from original value

-          Overexploitation

o   Humans harvest organisms faster than the organisms are able to reproduce

-          Introduction of exotic species

o   Exotic species introduced often compete with native species and drive them to extinction

-          Persecution of pest organisms

o   Many large carnivores (tigers etc) were hunted to extinction because of their threat to humans and their livestock

Habitat Loss

-          World Conservation Union (IUCN- International Union for Conservation of Nature) estimates that 80-90% of threatened species are under threat because of habitat loss or fragmentation

-          Activities that cause habitat loss

§  Farming (40% of world’s land surface has been converted to agriculture land), deforestation, grazing by livestock, modification of aquatic habitats, and conversion to urban and industrial landscapes

Special concerns about tropical deforestation

·         Tropical forests have greater species diversity than other terrestrial ecosystems; tropical soils have low fertility. Thus we cannot manage or cut down tropical forests like westerners do for their temperate forests

·         Tropical forests form the bulk of CO₂ trapping for the world so cutting down forests reduce this CO₂ sequestration and increase the rate of global warming

·         Human population growth in the tropical region if faster thus the forests are being cut down faster to convert them to farmland to feed the increasing population.

Today in the news: Reuters News Alert

›  INTERVIEW-Indonesia wants incentives to halt deforestation

BEIJING, Sept 19 (Reuters) - Indonesia is mobilizing a group of eight nations ahead of upcoming climate talks to get rich countries to pay the world's tropical nations not to chop down rainforests, its forestry minister said on Wednesday.

Participants from 189 countries are expected to gather in Bali at a U.N.-led summit in December. They will hear a report on Reduced Emissions from Deforestation (RED) -- a new scheme that aims to make emission cuts from forest areas eligible for global carbon trading.

Indonesia wants to gain bargaining power for direct assistance by teaming up with Brazil, Cameroon, Congo, Costa Rica, Gabon, Malaysia and Papua New Guinea, which together account for the lion's share of the world's tropical rainforests.

"What the 'F8' (Forest Eight) hopes and wishes for is an incentive from developed countries, an appreciation of each one's efforts to avoid deforestation," Malam Sembat Kaban told Reuters during a visit to Beijing on Wednesday.

"For instance, Indonesia has the potential to sell 14 million cubic meters of logs based on sustainable principles. Indonesia's policy is to exploit only 9 million cubic meters of logs" from natural forests, through selective cutting, Kaban said, speaking through an interpreter.

"Who pays? We are saving the forest but taking an economic loss ... The demand is there, so there is no reason not to cut."

Indonesia is home to 60 percent of the world's threatened tropical peatlands -- dense tropical swamps that release big amounts of CO2 when burnt or drained to plant crops such as palm oil. It is one of the world's top three carbon emitters when peat emissions are added in, said a report sponsored by the World Bank and Britain's development arm

Wildlife Management:

   “The application of ecological knowledge to populations of vertebrate animals and their plant and animal associates in a manner that strikes a balance between the needs of those populations and the needs of people”

-          􀂄Rooted in human ethics, culture, perceptions, and legal concepts

-          -conflicts between multiple parties, who supports, who pays

-          Trends in World Fish production- amount of fish captured increase yearly until 1989, then the amount has remained constant. This indicates that the world’s fisheries are being exploited to their capacity.  Aquaculture may be the solution but has environmental impacts such as algal blooms (eutrophication) as a result of nutrient release from fish farms.

-          Wildlife conservation

-          Wildlife conservation is defined as the regulation of wild animals and plants in order to ensure the continued sustenance of wildlife resources

-          The term wildlife conservation has been used to include an ever-widening group of animals and plants including mammals, birds, fish, reptiles, amphibians, arthropods (lobsters and spiders), mollusks

-          Wildlife Manager – maintains or manipulates wildlife populations, habitats, or human users to produce benefits for wildlife and the general public.  Benefits sought may be ecological, economic, social, recreational, or scientific.  A wildlife manager uses wildlife science to formulate and apply scientifically sound solutions to wildlife and habitat management problems.

-          Wildlife Biologist – gathers, analyzes, and interprets data on wildlife and habitats, including behavior, disease, ecology, genetics, nutrition, population dynamics, physiology, land-use changes, and pollution to conserve wildlife species and improve habitat conditions.  A wildlife biologist uses scientific principles to research wildlife and habitats to increase our knowledge base.

-          Wildlife Law Enforcement Officer – enforces wildlife laws and regulations to maintain wildlife populations at desired levels.  Wildlife law enforcement officers often perform surveys of wildlife populations, are involved in trapping and banding programs, implement wildlife population controls, respond to complaints of nuisance wildlife, and educate the public about wildlife issues.

-          Wildlife Inspector and Forensics Specialist – intercepts smuggled, illegal shipments of live wild animals for the pet trade and wild animal parts for trophy or medicinal purposes.  Wildlife inspectors are stationed at international airports, ocean ports, and border crossings.  Forensics specialists perform scientific and investigative work to document the origin and nature of evidence collected on these illegal imports (pegawai Perhilitan)

3 Management Approaches

        Preservation

                        - nature takes its own course, no human intervention

        Conservation

                        -maintain and use natural resources wisely

        Management

                        Direct Manipulation

                        -animal populations are trapped, shot poisoned, and stocked

                        Indirect Manipulation

                        - Vegetation, water, and other key components or wildlife habitat are altered

Conservation – Preservation

·         Conservation is sensible and careful

management of natural resources

·         Preservation involves setting aside undisturbed areas, maintaining them in a pristine state, and protecting them from human activities that might alter their “natural” state

Conservation and preservation

Planting fields in curves that conform to the natural contours of the land conserves soil by reducing erosion

The Arctic National Wildlife Reserve preserves caribou and other wildlife populations and their habitats

Yellowstone National Park, USA (First national park in the world)

·         In order to safeguard its precious natural heritage, Malaysia has set aside many areas as parks and wildlife reserves. Together with natural forest management, conservation of wildlife, birds and marine life, nature reserves have been established through a network of protected areas. Almost one and a half million hectares of conservation areas are protected by legislation.

·         All of Malaysia’s national parks are under the jurisdiction of Department of Wildlife and National Parks Malaysia

Role of Malaysia’s National Parks

·         As a virgin forest reserve and arboretum (tempat pembelajaran dan penyelidikan konservasi)

·         To conserve specific forest types : Hutan Paya Laut, Hutan Pantai, Hutan Rawa (Heath forest), Hutan Paya Gambut, Hutan Pamah Dipterokarpa, Hutan Bukit Dipterokarpa, Hutan Bukit Tinggi Dipterokarpa dan Hutan Pergunungan (from Kelantan Forestry Dept)

·         conservation of biodiversity : wildlife, birds and marine life, geological features (Langkawi GeoPark)

·         To protect endangered species such as the tiger, rhinoceros, butterflies, plants

·         To ensure sustainability (kelestarian) of the environment

·         To protect water resource and ensure constant supply of water

·         To provide recreation and ecotourism

Taman Negara

·         Spans 4,343 sq. km and sprawls across the mountainous interiors of Kelantan, Pahang, and Terengganu is Taman Negara, Malaysia's premier national park

·         Taman Negara is thought to be one of earth's oldest rain forest

·         Within this area, around the central masif of Gunung Tahan (the Peninsula's highest peak at 2,187 meters), there are countless limestone hills covered in thick forest, fast running streams, and abundant wildlife

·         Flora Fauna : Over 10,000 species of plants, 350 species of birds. Local mammals include mouse deer, barking deer, tapirs, wild boars, elephants, leopards, tigers, and monkeys 

·         Sepilok Orang Utan Rehabilitation Centre

·         Bako National Park:

o   Sandstone Cliffs Telok Sapi

o   Proboscis monkey

o   Nepenthes pitcher plant

·         Mulu National Park

o   Limestone hill

o   Dipterocarp tree

o   Stalagmites cleawater cave sys

BRIEF HISTORY OF WILDLIFE MANAGEMENT

Brief History

·         Neglect and Exploitation of North American Wildlife

o   Main Reason

§  Infinite Resource (Ex: Bison, wood ducks, passenger pigeon)

·         Cultures advance only when their participants learn from history

Aldo Leopold- Father of wildlife conservation

·         Likely most influential figure conservation in the 20th centuryury

 He said:  “can’t manage species if you don’t have anything to work with”

He also said: trained biologists to use scientific information as the basis for decision making (research)

Problems of Excess

·         Not all wildlife management deals with scarcity of animals

·         Problems can come from overabundance of particular species

ES 4 - Biomes

Topic 4 - Biomes

Biomes

-          Areas sharing similar climate, topographic and soil conditions, basic types of biological communities

-          Biome distribution determinant: precipitation & temperature (latitudinal bands)

Altitude depends on temp & precipitation

Vertical zonation (vegetation zones defined by altitude)

Tropical rainforest

-          Humid; support most complex & biologically rich biomes

-          Cloud forest: high mountains, fog & mist continually wet vegetation

-          Tropical rainforest: >200 cm or 80 inch / year; warm temp.

-          1/2 to 2/3 of all species dwells

-          Soil

o   Thin, acidic, nutrient poor

o   90% nutrients in organisms

o   Rapid decomposition & nutrient cycling

o   Soil cannot support continued cropping & rain erosion

o   Rapid deforestation due to immigration

Tropical Seasonal Forest

-          Many tropical regions are characterized by wet and dry seasons with hot temperatures year round.  These support tropical seasonal forests.

-          Brown and dormant much of the year but become green during the rainy season

-          Many of the plants are drought deciduous, i.e. they lose their leaves when it is dry.

-          Few of the tropical seasonal forests remain in their  natural state as humans use fire to clear the land in the dry season and settle there.

-          Soil is richer than rainforest, therefore more productive land for agriculture.

Tropical Savannas and Grasslands

•          Grasslands with sparse tree cover are called savannas. 

•          Rainfall amounts do not support forests

•          Dry season prone to fire

•          Plants with deep, long-lived roots and other adaptations to survive drought, heat, and fire

•          Many migratory grazers such as antelope, wildebeest, or bison

Desert

•          Characterized by low moisture levels (less than 30 cm per year) and precipitation that is infrequent    and unpredictable from year to year. 

•          Have wide daily and seasonal temperature fluctuations.

•          Plants exhibit water conservation characteristics such as water-storing stems, thick epidermis to reduce water loss, and salt tolerance.

•          Many plants bloom and set seed only after spring rains.

•          Animals also have adaptations.  Many are nocturnal and able to conserve water.

•          Deserts are vulnerable.

•          Slow growing vegetation is damaged by off road vehicles. It takes decades for desert soils to recover.

•          Overgrazing - Livestock are destroying the plants of the southern Sahara.   Without plants the land cannot retain what little rainfall there is and it becomes more barren.

Temperate Grasslands

-          Communities of grasses and seasonal herbaceous flowering plants

-          Few trees due to inadequate rainfall

-          Large daily and seasonal temperature fluctuations

-          Thick organic soils

-          Much converted to farmland.  Tallgrass prairies in the U.S. are now mostly farms.

-          Overgrazing is a threat because it kills the plants and permits erosion to occur.

Temperate Shrubland (Mediterranean)

-          Characterized by warm, dry summers and cool, moist winters

-          Evergreen shrubs, scrub oaks, pines

-          Fires are a major factor in plant succession.

-          Referred to as chaparral in California

-          High number of unique species

-          Human homes built in chaparral harm endangered wildlife and burn periodically.

-          Also found along Mediterranean coast, southwestern Australia, central Chile and South Africa

Temperate Deciduous Forest

-          Temperate regions support lush summer plant growth when water is plentiful.

-          Deciduous trees lose their leaves in winter as an adaptation to freezing temperatures.

-          Eastern half of U.S. was covered with broad leaf deciduous forest when European settlers arrived.  Much of that was harvested for timber.

-          Areas in U.S. have re-grown, although the dominant species are different

-          Areas in Siberia severely threatened now, may be region with greatest rate of deforestation in the world today

Boreal Forests

•          Boreal Forest - Northern Coniferous Forest

v  Broad band of mixed coniferous and deciduous trees between 50° and 60° N latitude

v  Dominated by pines, hemlock, spruce, cedar  and fir with some deciduous trees mixed in

•          Taiga - Northernmost edge of boreal forest

v  Extreme cold and short summers limit the growth rate of trees.  A tree that is 4 inches (10 cm) in diameter may be over 200 years old.

Marine Ecosystem

-          Oceans cover 3/4 of Earth’s surface.

-          Photosynthesis is carried out by algae or free floating plants (phytoplankton).  Greatest amount of photosynthesis near the coast where nutrients wash in.

-          Organisms die and fall to sea floor where the nutrients are used in deep ocean ecosystems. 

-          Upwelling currents circulate nutrients from the ocean floor back to the surface.

-          Vertical stratification is a key feature.

-          Light and temperature decrease with depth and deep ocean species often grow slowly.

-          Cold water holds more oxygen than warm water so productivity is often high in cold oceans such as the North Atlantic.

-          Ocean systems classified by depth and location to shore:

-          Benthic -  bottom

-          Pelagic - water column above the bottom

-          Area near shore is known as littoral zone

Surface to Hadal Zone Communities

-          Open ocean is a biological desert except for areas where nutrients are distributed by currents e.g. Sargasso Sea in the Atlantic

-          The deepest layer of the ocean (hadal zone) contains communities of tube worms, mussels, etc. supported by microbes that capture chemical energy from thermal vents on the ocean floor.  These organisms are adapted to extreme temperatures (350^oC) and intense pressure.

Coastal Zones

-          Communities vary with depth, light, temperature and nutrient concentration.

-          Coral Reefs - Aggregations of coral polyps that live symbiotically with algae.  Their calcium rich skeletons build up the reef.

-          Found in shallow water as light must penetrate for algal photosynthesis.

-          Threatened by trash, sewage, urban runoff, industrial waste, introduced pathogens and global warming.  Global warming causes coral bleaching in which corals expel their algal partners and then die.

-          One third of coral reefs have already been destroyed and 60% of the remaining reefs will probably be dead by 2030 ( 2006 UNESCO Conference).

-          Economically important due to tourism.

Mangrove

-          Mangroves are trees that grow in saltwater along tropical coastlines.

-          Help stabilize shoreline

-          Nurseries for fish, shrimp

-          Can be cut for timber

Tidal Environments

-          Estuaries - bays or semi-enclosed bodies of brackish water that form where rivers enter the ocean

-          Salt marshes - coastal wetlands flooded regularly or occasionally by seawater

-          Both are nutrient rich and biologically diverse.

-          2/3 of marine fish and shellfish rely on estuaries for spawning and development.

-          Threatened by sewage from coastal cities

Tide Pools

-          Depressions in a rocky shoreline that are flooded at high tide but retain some water at low tide

-          Wave action prevents most plant growth, but animals can be found in tidal pools.

-          Diverse specialized species adapted to the harsh conditions.

Barrier Islands

-          Narrow islands made of sand that form parallel to a coastline

-          Provide protection from storms, waves, tides

-          Since they are made of sand, they should not be built on, but they are.  Oftentimes, storms destroy the buildings.

-          About 20% in the US have been developed.

Freshwater Ecosystems

-          Lakes

-          Freshwater lakes have distinct vertical zones.

-          Epilimnion - warm upper layer

-          Hypolimnion - cold, deeper layer that does not mix

-          Thermocline - distinctive temperature transition zone that separates warm upper layer and deeper cold layer

-          Benthos - bottom

Wetlands

-          Land surface is saturated or covered with water at least part of the year.

-          Swamps - Wetlands with trees.

-          Marshes - Wetlands without trees.

-          Bogs and Fens - Waterlogged soils that tend to accumulate peat. Bogs fed by precipitation, while fens are fed from groundwater.  Nutrient poor with low productivity, but many unusual species.

-          Water usually shallow enough to allow full sunlight penetration, so the majority of wetlands have high productivity.

-          Trap and filter water, and store runoff.

-          Conservation is very important due to rich biodiversity.  Wetlands are the breeding grounds for birds. One of the greatest areas of concern for biologists.

-          May gradually convert to terrestrial communities through succession

Human Disturbance

-          By some estimates, humans preempt about 40% of net terrestrial primary productivity.

-          Conversion of habitat to human use is single largest cause of biodiversity loss.

-          Temperate deciduous forests are the most completely human-dominated biome.  Tundra and Arctic Deserts are the least disturbed.

-          About half of all original wetlands in the U.S. have been degraded over the past 250 years.

Tropical Savannahs & Grasslands

Deserts

Temperate Grasslands

Temperate Deciduous Forests

Temperate Rainforests

Boreal Forests

Tundra