Transcript LAND MANAGEMENT - lakeland.k12.nj.us

LAND MANAGEMENT
Abuse of the Land
 Tragedy of the Commons
 Deforestation
 Provide fuel & building materials, space for growing food, cash
crops or cattle
 Desertification
 Nutrients & moisture depleted
 Waterway & wetland alteration
 No longer provide ecological cleansing & biodiversity
 Urbanization
 Move away from self sufficiency into pools of pollution
 Solid Waste
 How do we store the “packaging” of our purchases?
Land Restoration & Reuse
 Maximized through
 Conservation
 Preservation
 Restoration
 Remediation
 Reclamation
 Mitigation
Conservation
 Not using & protecting resources that could be expended
with less responsible pattern of use
 Decreases use
 Example
 It is less expensive to educate consumers about using less power than it is
to find new sources
Preservation
 Providing an ample reserve of resources so that they may be
enjoyed by others in the future
 Protects resources
 Examples
 Park Service Act of 1916 – sought to preserve natural features, unique
populations and historical objects for the enjoyment of future generations
 1964 Wilderness Act – established wilderness areas and wildlife refuges
 Currently 1% of the US is preserved as wildlife refuge
 1980 Alaska National Interest Land Act increased acreage
Restoration
 Bringing a damaged ecosystem back to its unspoiled, natural
condition
 Example
 Nature Conservancy restoring 40,000 acres of prairie in Kansas (fires &
Bison)
Remediation
 Using chemical, biological or physical methods to remove
toxic or hazardous pollutants
 Chemical – neutralizing acids or oxidants
 Biological – bacterial digestion of oil or nutrients, using plants
to remove nutrients from wastewater
 Physical – vaporization of hydrocarbons from broken oil pipes
 CERCLA (1980,1984) – Comprehensive Environmental
Response, Compensation and Liability Act – SUPERFUND –
cleanup of toxic waste dump sites
Reclamation
 Using large water supply projects to bring water to un-arable
land
 Movement of earth to return massively scarred, denuded or
devastated land to an environmentally useful and socially or
politically acceptable condition
 Examples
 Surface Mining Control & Reclamation Act (SMCRA,1977) – requires
escrowed funds to be used to reclaim land after open-pit mining
operations – reburying mine tailings, refilling open pits, returning
surfaces to a more natural topography
Mitigation
 Finding a solution to a problem
 Refers to establishing another ecosystem elsewhere of
comparable health and magnitude in exchange for damage
done as a result of developing a nearby area
 Example
 Fish and Wildlife Conservation Act of 1980
Managing Mineral Resources and
Mining
 US imports 50% of needed mineral resources
 Common Metal Mineral Resources
 Aluminum – usually mined as bauxite, requires large amounts of
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energy to process into metal
Chromium
Copper
Gold
Iron
Lead
Manganese
Nickel
Platinum
Silver
Uranium
Managing Mineral Resources and
Mining
 Common Nonmetal Mineral Resources
 Silicates
 Sand
 Gravel
 Limestone
 Evaporites
 Sulfur
 Coal
 Oil
Managing Mineral Resources and
Mining
 The Mining Operation
 Due Diligence
 Site analysis – evaluate site for potential of cost-effective mineral
extraction
 Leases, Licensing, Permits – company registers with state agency that
implements SMCRA (Surface Mining Control and Reclamation Act of
1977), if land is public, lease with government negotiated
 Extraction
 Surface Mining – overburden removed & stored
 Seam is mined or whole mountain displaced
 Sub-surface Mining – underground used to extract deeper deposits
 Risky for miners (explosions, lack of O2, gases, fires, collapses)
 Tailings must be removed, may leach toxins to surface waters
 Wells –extraction of fluids
Managing Mineral Resources and
Mining
 The Mining Operation
 Processing
 Heap-Leach Extraction for Gold
 Pile of gold sprayed with acidified cyanide to dissolve gold
 Electrolyte reduction used to extract gold
 Cyanide can be reused
 When mining operations complete toxic cyanide often left behind
 Uranium Processing
 Environmentally devastating – at each step nuclear waste produced
o 100 tons of ore mined, 0.8 tons purified
o 99.2 tons high-level nuclear waste
 Aluminum Electrolytic Extraction – energy intensive
o Ore is crushed, melted, then put in large vats with electrodes
Managing Mineral Resources and
Mining
 The Mining Operation
 Reclamation
 SMCRA requires mining operations to put money into an escrow
account to reclaim mining sites
 Overseen by states
 Return of overburden
 Topsoil put down & plants grown
 Highwalls sculpted to appear natural
 Tailings removed & placed where leaching and acid runoff prohibited
 Environmental Consequences of Mining
 Land deformed from digging or erosion
 Mine tailings exposed to rain become toxic spoiling soil, destroying
streams and rivers, or contaminates groundwater
 Particulate air pollution
Managing Agriculture and Forestry
 The land must contain the nutrients needed to grow the food
 Human nutritional needs
 2,000-2,500 calories otherwise – undernourished
 Humans need 22 different amino acids to build proteins (body can
synthesize all but 8 – essential amino acids)
 Contained in meat & cheese, legumes & grains
 Famines – massive acute incidences of undernourishment catalyzed by
political or economic upheaval, or environmental devastation
 Overnutrition – Americans consume 1000-1500 more calories than
necessary
 1.1 billion people are overweight
 Malnourishment – inability to acquire adequate vitamins and
nutrients – can eventually lead to disease
Eating animal products has significant
impacts
 As wealth and commerce increase, so does consumption of meat, milk,
and eggs
 Global meat production has increased fivefold
 Per capita meat consumption has doubled
Domestic animal production for food increased from 7.3 billion in 1961 to
20.6 billion in 2000
Feedlot agriculture
 Feedlots (factory farms) = also
called Concentrated Animal
Feeding Operations (CAFOs)
 Huge warehouses or pens designed
to deliver energy-rich food to
animals living at extremely high
densities
 Over ½ of the world’s pork and
poultry come from feedlots
Debeaked chickens spend their lives in cages; U.S. farms can house hundreds of
thousands of chickens in such conditions
The benefits and drawbacks of feedlots
 The benefits of feedlots include:
 Greater production of food
 Unavoidable in countries with high levels of meat consumption,
like the U.S.
 They take livestock off the land and reduces the impact that they
would have on it
 Drawbacks of feedlots include:
 Contributions to water and air pollution
 Poor waste containment causes outbreaks in disease
 Heavy uses of antibiotics to control disease
Energy choices through food choices
 90% of energy is lost every time
energy moves from one trophic level
to the next
 The lower on the food chain from
which we take our food sources, the
more people the Earth can support.
 Some animals convert grain into meat
more efficiently than others
Environmental ramifications of eating meat
 Land and water are needed to raise food for livestock
 Producing eggs and chicken meat requires the least space and
water
 Producing beef requires the most
When we choose what to eat, we also choose how we use resources
Managing Agriculture and Forestry
 Land degradation
 Desertification – the process of converting farmable grassland
into nonarable desert
 Land is overfarmed, nutrients and organic material depleted
 Erosion – soil moved from its point of origin
 Water and wind can remove topsoil
 Chemical nutrient depletion or salinization (watering with brackish
water)
 Physical compaction by machines or cattle
 Excessive water (overirrigation, poor drainage or ocean encroachment)
Managing Agriculture and Forestry
 Land degradation
 Pesticide use
 Toxicity to non target species – bioaccumulation & biomagnification
 Pest resistance and resurgence – a few hardy insects survive & bloom in a pest
resurgence
 Types of pesticides
 Inorganic pesticides – arsenic, copper, mercury, lead – toxic & persistent
 Chlorinated hydrocarbons – DDT, aldrin, lindane, toxaphene – block
nerve transmission – bioaccumulate & biomagnify
 Organophosphates – parathion, malathion – neurotoxin & not persistent
 Carbamates – carbofuron and aldicarb – behave like organophosphates
 Botanical pesticides – pyrethrum – extracted from botanicals
Managing Agriculture and Forestry
 Land degradation
 Pesticide use
 Integrated Pest management (IPM) – non-chemical solutions to pests
 Combination of strategies
 Nonchemical –
o use of natural predators, sex pheromones to attract, introduce
sterile breeding partners, crop rotation
 Chemical –
o Greater deliberation & specific targeting
• Planting trap crops that mature earlier & attract pests, spraying &
destroying trap crop
Managing Agriculture and Forestry
 Land degradation
 Fertilizer use
 Overuse can cause nutrient pollution
 Alternate – crop rotation of nitrogen-demanding with nitrogenproducing (peas, alfalfa, clover)
 Energy use
 Current farming practices depend on fossil fuels
Managing Agriculture and Forestry
 Sustainable Agriculture vs Industrial Monoculture
 Subsistence farming – grow only what is needed to support needs of
grower
 More than 65% of global population
 Industrial monoculture – planting large tracts of land with a similar
crop, same maintenance techniques applied
 Higher yields
 Larger accumulation of one type of pest
 Sustainable farming
 Low or no-till farming & contour farming
 Uses crop rotation & polyculture
 Uses natural fertilizers
 Minimizes pesticide use
 Minimizes use of fossil fuels
 Minimizes use of irrigation
Managing Agriculture and Forestry
 Farming vs Ranching
 Ecological aspects of Meat Production
 Total energy input – more energy to produce meat
 Feedlot pollution
 Give antibiotics, growth hormones
 Runoff contains antibiotics & hormones & nutrients
 Overgrazing Public Lands
 Use of National Forests & BLM Land
 In west 75% of land is available for grazing
 Permits cost 3-5% of the true cost of grazing land
 85% of government-owned rangeland is considered poor quality land
Managing Agriculture and Forestry
 Agricultural “Revolutions”
 Green Revolution
 1950s scientists develop strains of crops the provide higher yields
 Fewer genetics strains of crops (where once there were several)
 Single strains became vulnerable to diseases & insects
 Greater dependence on expensive seeds, chemical fertilizers & pesticides
Resistance to pesticides
 Some individuals are genetically immune to a pesticide
 They survive and pass these genes to their offspring
 Pesticides stop being effective
 Evolutionary arms race: chemists increase chemical toxicity to
compete with resistant pests
Biological control
 Biological control
(Biocontrol) = uses a pest’s
natural predators to control the
pest
 Reduces pest populations without
chemicals
 Cactus moths control prickly pear
 Bacillus thuringiensis (Bt) =
soil bacteria that kills many pests
Biocontrol agents may become pests
themselves
 No one can predict the effects of an introduced species
 The agent may have “nontarget” effects on the environment and
surrounding economies
 Cactus moths are eating rare Florida cacti
 Removing a biocontrol agent is harder than halting pesticide use
 Due to potential problems, proposed biocontrol use must be carefully
planned and regulated
Managing Agriculture and Forestry
 GMOs (Genetically Modified Organisms) or Transgenic Species
 Moving genes from one species to another
 Hoped to produce strains more resistant to pests & adverse
environments, more durable in shipping, yield better nutrients, grow at
different times of the year
 Represent 70% of food grown & sold in the US
Genetically modified organisms
 Genetic engineering =
laboratory manipulation of genetic
material
 Genetically modified
organisms = organisms that have
been genetically engineered by …
 Recombinant DNA = DNA
created from multiple organisms
Genetic engineering has benefits and risks
 Benefits of genetic engineering:
 Increased nutritional content
 Increased agricultural efficiency
 Rapid growth
 Disease and pest resistance
 Negatives of genetic engineering:
 Risks are not yet defined or well understood
 Protests from environmental activists, small farmers, and consumer
advocates
Biotechnology is impacting our lives
 Biotechnology = the material application of biological
science to create products derived from organisms
 Transgenic organism = an organism that contains DNA
from another species
 Transgenes = the genes that have moved between organisms
 Biotechnology has created medicines, cleaned up pollution,
and dissolves blood clots
Some genetically modified foods
Genetic engineering versus agricultural
breeding
 Artificial selection has influenced the genetic makeup of livestock and crops
for thousands of years
 Proponents of GM crops say GM foods are safe
 Critics of GM foods say:
 Traditional breeding uses genes from the same species
 Selective breeding deals with whole organisms, not just genes
 In traditional breeding, genes come together on their own
Traditional breeding changes organisms through selection, while genetic
engineering is more like the process of mutation
Biotechnology is changing our world
 GM foods become big business
 Most GM crops are herbicide resistant
 Farmers apply herbicides to kill weeds, and crops survive
 Most U.S. soybeans, corn, cotton, and canola are genetically modified
Globally, more than 10 million farmers grew GM foods on 102 million ha of
farmland, producing $6.15 billion worth of crops
What are the impacts of GM crops?
 As GM crops expanded, scientists and citizens became concerned
 Dangerous to human health
 Escaping transgenes could pollute ecosystems and damage nontarget
organisms
 Pests could evolve resistance
 Could ruin the integrity of native ancestral races
 Interbreed with closely related wild plants
Supporters maintain that GM crops are
safe
 Supporters make the following points:
 GM crops pose no ill health effects
 They benefit the environment by using less herbicides
 Herbicide-resistant crops encourage no-till farming
 GM crops reduce carbon emissions by needing fewer fuel-burning
tractors and sequestering carbon in the soil by no-till farming
 Critics argue that we should adopt the precautionary principle =
don’t do any new action until it’s understood
Studies on GM foods show mixed
results
 Between 2003 and 2005, the British government commissioned three
large-scale studies, which showed
 GM crops could produce long-term financial benefits
 Little to no evidence was found of harm to human health, but effects on
wildlife and ecosystems are not well known
 Bird and invertebrate populations in GM fields were mixed; some crops
showed more diversity, some less, depending on the crop
The GM debate involves more than science
 Ethical issues plays a large role
 People don’t like “tinkering” with “natural” foods
 With increasing use, people are forced to use GM products, or go to
special effort to avoid them
 Multinational corporations threaten the small farmer
 Research is funded by corporations that will profit if GM foods are
approved for use
 Crops that benefit small, poor farmers are not widely commercialized
The GM industry is driven by market considerations of companies selling
proprietary products
GMO producers are suing farmers
Farmers say that “[they] are being sued for having GMOs on
their property that they did not buy, do not want, will not use,
and cannot sell”
 Monsanto has launched 90 lawsuits against 147 farmers,
winning an average $412,000 per case
 Monsanto charged farmer Percy Schmeiser of Canada with using
its patented GM seeds without paying for them
 Schmeiser charged the seeds blew onto his field from the
neighbor’s adjacent field
 The courts sided with Monsanto, saying Schmeiser had violated
Monsanto’s patent
Nations differ in their acceptance of GM
foods
 Europe opposed GM foods
 The U.S. sued the European Union before the World Trade Organization,
charging that the European Union was hindering free trade
 Brazil, India, and China approve GM crops
 Zambia refused U.S. food aid, even though people were starving, because
some seeds were genetically modified
Sustainable Agriculture
 Industrial agriculture may seem necessary, but less-intensive agricultural
methods may be better in the long run
 Sustainable agriculture = does not deplete soil, pollute water, or decrease
genetic diversity
 Low-input agriculture = uses smaller amounts of pesticide, fertilizers,
growth hormones, water, and fossil fuel energy than industrial agriculture
 Organic agriculture = Uses no synthetic fertilizers, insecticides, fungicides,
or herbicides
 Relies on biological approaches (composting and biocontrol)
A standardized meaning for “organic”
 People debate the meaning of the word “organic”
 Organic Food Production Act (1990) establishes national standards for
organic products
 The USDA issued criteria in 2000 by which food could be labeled
organic
 Some states pass even stricter guidelines for labeling
The market for organic food is
increasing
 Sales increased 20%/year in Canada
and the U.S. from 1989-2005
 Expanded by a factor of 40 in
Europe
 Amount of land for organic farming is
increasing
 10-35%/year in the U.S. and
Canada
 In 2005 the U.S. had 1.7 million
acres of organic cropland and 2.3
million acres of organic pastureland
The benefits of organic farming
 For farmers:
 Lower input costs, enhanced income from higher-value products,
reduced chemical costs and pollution
 Obstacles include the risks and costs of switching to new farming
methods and less market infrastructure
 For consumers:
 Concern about pesticide’s health risks
 A desire to improve environmental quality
 Obstacles include the added expense and less aesthetically appealing
appearance of the product
The U.S. doesn’t financially support
organic farmers
 In 1993, the European Union adopted a policy to support
farmers financially during conversion to organic farming
 The U.S. offers no such support
 Organic production lags in the U.S.
 Farmers can’t switch, because they can’t afford the temporary loss
of income
 In the long run, organic farming is more profitable
Organic agriculture succeeds in cities
 Community gardens = areas where residents can grow their own
food
 In Cuba, over 30,000 people work in Havana’s gardens, which cover
30% of the city’s land
 Record yields for 10 crops in 1996-1997
Locally supported agriculture is
growing
 In developed nations, farmers and
consumers are supporting local smallscale agriculture
 Fresh, local produce in season
 Community-supported agriculture
= consumers pay farmers in advance for a
share of their yield
 Consumers get fresh food
 Farmers get a guaranteed income
Managing Agriculture and Forestry
 Use of forests
 30% of world’s land area
 Absorbs precipitation
 Controls climate
 Provides oxygen
 Purifies air
 Produces usable resources
 Creates habitat
Ecological value of forests
 One of the richest ecosystems for biodiversity
 Structural complexity houses great biodiversity
 A forest provides many ecosystem services
 Stabilizes soil and prevents erosion
 Slows runoff, lessens flooding, purifies water
 Stores carbon, releases oxygen, moderates climate
Loggers moved westward, searching for
large trees
 Primary forest = natural forest uncut by people
 Little remained by the 20th century
 Second-growth trees = grown to partial maturity after old-growth
timber has been cut
Managing Agriculture and Forestry
 Current Forest Harvesting Practices
 Clear-cutting – cutting every tree regardless of species or size
 Large trees dragged to access roads
 Smaller trees wasted
 Soil exposed to erosion
 Habitat disrupted
 Selective cutting – harvesting a portion of mature trees
 Better growth
 More stable habitat
 Protects from erosion
Managing Agriculture and Forestry
 Current Forest Harvesting Practices
 Swidden or milpa agriculture – used by indigenous people of tropical
rainforests
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Farmer clears small plot by cutting or burning
Ashes provide nutrients
Crops are planted or harvested during natural succession of forest
Sustainable as long as density of farmers does not exceed forest’s ability to
regenerate
 Rainforest Deforestation – to grow hardwood and commercial food
crops (sugar & coffee)
 Rainforests contain 2/3 of global biomass & ½ of global biodiversity
 Threatens biodiversity, climate stabilization, flood control & O2 production
Managing Agriculture and Forestry
 Current Forest Harvesting Practices
 Forestry as Agriculture
 Monoculture forestry
 Dense single species stands
 Increases yield & ease of harvesting
 Encourages disease & pest infestation
Managing Agriculture and Forestry
 Current Forest Harvesting Practices
 Fire Management
 Past practice was to eliminate all fires
 This allowed undergrowth to grow unabated
 Fires then became more damaging
 Eliminated benefits from fires (open seed cones, meadows for wildlife)
 Current policy is “let burn” – use fire-fighting resources only when lives
or property are threatened
 Burned forests are essential part of natural and healthy cycle
The National Forest Management Act
(1976)
 Mandated that plans for renewable resource management had to be drawn up
for every national forest
 Guidelines included:
 Consideration of both economic and environmental factors
 Provision for species diversity
 Ensuring research and monitoring
 Permitting only sustainable harvests
 Protection of soils and wetlands
 Assessing all impacts before logging to protect resources
Maximum sustainable yield
 Maximum sustainable yield = aims to achieve the maximum
amount of resource extraction
 Without depleting the resource from one harvest to the next
 Populations grow most rapidly at an intermediate size
 Population size is about half its carrying capacity
 Managed populations are well below what they would naturally be
Reducing populations so drastically
affects other species and can change
the entire ecosystem
Livestock graze one-fourth of Earth’s
land
 Grazing can be sustainable if done carefully and at low intensity
 Bureau of Land Management (BLM) = owns and manages most
U.S. rangeland
 Nation’s single largest landowner: 106 million ha (261 million acres)
across 12 western states
 Ranchers can graze cattle on BLM lands for low fees
 Low fees encourage overgrazing
Ranchers and environmentalists have joined to preserve ranchland against
development and urban sprawl
Management of the American West
 Overexploitation of resources caused great
damage to the American West
 Poor farming practices, overgrazing, farming
arid lands
 John Wesley Powell in the late 1800s called for
agencies to base management on science
 Farming Western lands had to account for arid
conditions
 His ideas were ignored, contributing to failures
such as the Dust Bowl of the 1930s
Parks and reserves
 Reasons for establishing parks and reserves include:
 Monumentalism = preserving areas with enormous, beautiful or
unusual features, such as the Grand Canyon
 Offer recreational value to tourists, hikers, fishers, hunters and others
 Protect areas with utilitarian benefits, such as clean drinking water
 Use sites that are otherwise economically not valuable and are therefore
easy to protect
 Preservation of biodiversity
Federal parks and reserves began in
the U.S.
 National parks = public lands
protected from resource extraction
and development
 Open to nature appreciation and
recreation
 Yellowstone National Park was
established in 1872
 The Antiquities Act of 1906
 The president can declare
selected public lands as national
monuments
The National Park Service (NPS)
 Created in 1916 to administer parks and monuments
 388 sites totaling 32 million ha (72 million acres)
 Includes national historic sites, national recreation areas, national
wild and scenic rivers
 273 million visitors in 2006
National Wildlife Refuges
 Begun in 1903 by President Theodore Roosevelt
 37 million ha (91 million acres) in 541 sites
 U.S. Fish and Wildlife Service administers refuges
 Management ranges from preservation to manipulation
 Wildlife havens
 Allows hunting, fishing, wildlife observation, photography, education
Wilderness areas
 Wilderness areas = area is off-limits
to development of any kind
 Open to the public for hiking, nature
study, etc.
 Must have minimal impact on the
land
 Necessary to ensure that humans
don’t occupy and modify all natural
areas
 Established within federal lands
 Overseen by the agencies that
administer those areas
Habitat fragmentation threatens species
 Contiguous habitat is chopped into small pieces
 Species suffer
The SLOSS dilemma
 Which is better to protect species?
 A Single Large Or Several Small reserves?
 Depends on the species: tigers vs. insects
 Corridors = protected land that allows animals to travel between
islands of protected habitat
 Animals get more resources
 Enables gene flow between populations
Biosphere reserves have several zones
 This can be a win-win situation for everyone
Aquaculture
 World fish populations are
plummeting
 Technology and increased
demand
 Aquaculture = raising aquatic
organisms for food in a
controlled environment
 Aquatic species are raised in
open-water pens or land-based
ponds
Aquaculture is growing rapidly
 The fastest-growing type of food production
 Provides a third of the world’s fish for human consumption
 Most widespread in Asia
The benefits and drawbacks of aquaculture
 Benefits:
 A reliable protein source
 Sustainable
 Reduces fishing pressure on
overharvested wild fish stocks
 Energy efficient
 Drawbacks:
 Diseases can occur, requiring
expensive antibiotics
 Reduces food security
 Large amounts of waste
 Farmed fish may escape and
introduce disease into the
wild
Managing Wildlife
 Traits of Endangered Species
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K-selected species
Species requires large amount of land (solitary ore migratory)
Narrowly defined niche
Low genetic diversity
 Genetic bottlenecks – many individuals eliminated, remaining gene pool
limited by that of remaining breeding pair
 Genetic isolation – small number of individuals isolated
 Genetic assimilation – when crossbred with related, hardier species
 Competes with hardier, dominant species
 Low tolerance for pollution
Managing Wildlife
 Causes of Extinction
 Loss of habitat
 Human development and pollution
 Competition with dominant or exotic species for same habitat
 Climate change or other abiotic factors make environment inhabitable
 Hunting
 Loss of genetic diversity
 Normal fluctuation of population that result in the total demise
of the population
Managing Wildlife
 Mitigating Extinction
 Monitor markets for endangered species
 Hunting and fishing created market for habitat protection
 Legislation
 Convention on International Trade in Endangered Species of Wild Fauna and Flora
(CITES, 1973)
 Bans international transport of endangered species body parts
 Endangered Species Act (ESA, 1973)
 Vulnerable – species at risk
 Threatened – species likely to become endangered
 Endangered – imminent danger of extinction
 Habitat Conservation Plans – use of natural resources as long as species
benefit
 In Situ Management – protect in existing parks, wilderness areas & preserves
 Ex Situ Management – zoos or captive breeding programs