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LAND USE, RESOURCES AND MANAGEMENT. Abuse of the Land Tragedy of the Commons Deforestation Provide fuel & building materials, space for growing food,

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Presentation on theme: "LAND USE, RESOURCES AND MANAGEMENT. Abuse of the Land Tragedy of the Commons Deforestation Provide fuel & building materials, space for growing food,"— Presentation transcript:


2 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?

3 Land Restoration & Reuse Maximized through Conservation Preservation Restoration Remediation Reclamation Mitigation

4 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

5 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

6 Restoration Bringing a damaged ecosystem back to its unspoiled, natural condition Example Nature Conservancy restoring 40,000 acres of prairie in Kansas (fires & Bison)

7 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

8 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

9 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

10 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

11 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

12 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

13 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

14 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

15 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

16 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)

17 Protecting soil: crop rotation and contour farming Crop Rotation = alternating the crops grown field from one season or year to the next, Cover crops protect soil when main crops aren’t planted Returns nutrients to soil, breaks disease cycles, reduces erosion Wheat or corn and soybeans Contour Farming = plowing furrows sideways across a hillside, perpendicular to its slope, to prevent rills and gullies

18 Protecting soil: terracing and intercropping Terracing = level platforms are cut into steep hillsides, sometimes with raised edges A “staircase” to contain water Intercropping = planting different types of crops in alternating bands or other spatially mixed arrangements Increases ground cover Reduces disease

19 Protecting soil: shelterbelts and reduced tillage Shelterbelts or Windbreaks = rows of trees or other tall, perennial plants that are planted along the edges of fields to slow the wind Alley cropping (agroforestry) = shelterbelts + intercropping + trees Reduced Tillage = furrows are cut in the soil, a seed is dropped in and the furrow is closed No-till farming disturbs the soil even less Can improve soil quality

20 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

21 Managing Agriculture and Forestry Land degradation Pesticide use Integrated Pest management (IPM) – non-chemical solutions to pests Combination of strategies Nonchemical – ouse of natural predators, sex pheromones to attract, introduce sterile breeding partners, crop rotation Chemical – oGreater deliberation & specific targeting Planting trap crops that mature earlier & attract pests, spraying & destroying trap crop

22 Managing Agriculture and Forestry Land degradation Fertilizer use Overuse can cause nutrient pollution Alternate – crop rotation of nitrogen-demanding with nitrogen- producing (peas, alfalfa, clover) Energy use Current farming practices depend on fossil fuels

23 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

24 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

25 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

26 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

27 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

28 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

29 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

30 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

31 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

32 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

33 Some genetically modified foods

34 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

35 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

36 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

37 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

38 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

39 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

40 GMO producers are suing farmers 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 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”

41 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

42 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)

43 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

44 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

45 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

46 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

47 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

48 Locally supported agriculture is growing In developed nations, farmers and consumers are supporting local small- scale 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

49 U.S. programs promote soil conservation Food Security Act of 1985: Farmers that adopt soil conservation plan receive price supports and other benefits Conservation Reserve Program (1985) Farmers are paid to stop cultivating and place highly erodible land into conservation reserves Trees and grasses are planted instead of crops Saves 771 million tons of topsoil per year Generates income for farmers Provides habitat for native wildlife

50 Federal Agricultural Improvement and Reform Act (1996) Known as the Freedom to Farm Act Aimed to reduce subsidies and government influence over farm products Created the Environmental Quality Incentive Program and Natural Resource Conservation Foundation Promotes and pays for conservation practices in agriculture Low-Input Sustainable Agriculture Program (USDA, 1998) Provides funding for sustainable agricultural practices for individual farmers

51 International soil conservation programs Food and Agriculture Organization (FAO) = the United Nations’ main agricultural program The FAO’s Farmer-Centered Agricultural Resource Management Program (FAR)… Helps farmers duplicate agricultural success stories Uses local communities to educate and encourage farmers to conserve soils and secure the food supply Supports innovative approaches to resource management and sustainable agriculture in around the world China, Thailand, Vietnam, Indonesia, Sri Lanka, Nepal, the Philippines and India

52 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

53 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

54 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

55 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

56 Managing Agriculture and Forestry Current Forest Harvesting Practices Swidden or milpa agriculture – used by indigenous people of tropical rainforests 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 & O 2 production

57 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

58 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

59 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

60 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

61 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

62 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

63 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

64 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

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