PowerPoint Presentation - Food_ Soil_ and Pest Management

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					Food, Soil, and Pest

       Chapter 10

  Brittany, Carly, and Emma
                      Key Concepts
   How is food produced?

   Green Revolutions and traditional farming

   Soil degradation and erosion

   Increasing food production

   Malnutrition

   Environmental impacts of food production

   Impacts of government policies on food production

   Sustainable agriculture
          Would You Eat Winged Beans
               and Bug Cuisine?

   People need protein

   Poor can’t afford meat

   Environmental impacts of livestock

   Winged bean

   Microlivestock
     •   Edible insects

   Why bugs are not popular food

                                         Fig. 10-2, p. 206
Caterpillars as Food
         •An example: Mopani
              •Emporer moth caterpillar
              •So popular in South America,
              being overharvested
         •Consuming more reduces
         •Lessens large environmental impact
         of producing forms of meat
         •Low carbohydrates, low fat sources,
         and 58-78% protein— 3 to 4 times
         the level found in chicken, eggs, fish,
         beef, etc.

         Fig. 10-1, p. 206
                   Food Production

   Major food sources (3): croplands, rangelands, and oceans

   Large increase in food production since 1950

   Need for environmental-friendly food production

   Impact of genetic engineering

   Problem of poverty

   Primary crops: wheat, corn, and rice

   Primary meat sources: fish, chicken, pigs, and cattle
               Types of Agriculture
   Two major types of agricultural systems: industrialized
    and traditional

   Industrialized (high-input) agriculture
    •   Monocultures (single crop), ¼ of all cropland, and developed countries

   Plantation agriculture (form of industrialized)
    •   Large monocultures, tropical developing countries (grown)
    •   Ex- bananas, soybeans, sugarcane, cocoa, and vegetables

   Traditional intensive agriculture
    •   Increase human labor, fertilizer and water- to produce enough to feed families and sell for

   Traditional subsistence agriculture
    •   Only enough for families survival
Principal Types of Food Production

  Industrialized agriculture   Plantation agriculture   Intensive traditional agriculture

  Shifting cultivation         Nomadic herding          No agriculture   Fig. 10-3, p. 208
Ecological and Economic
 Services of Croplands
                 Natural Capital

 Ecological                              Economic
 Services                                Services

•Help maintain water flow and         •Food crops
 soil infiltration

•Provide partial erosion protection   •Fiber crops

•Can build soil organic matter
                                      •Crop genetic
•Store atmospheric carbon

•Provide wildlife habitat for some    •Jobs
                                                      Fig. 10-4, p. 209
     Food Production in the Green
   Develop plant monocultures

   High yields with fertilizers, pesticides, and water

   Multiple cropping

   First and second revolutions

   Environmental impacts

   Energy use
                         Green Revolutions

First green revolution     Second green revolution   Major international agricultural
(developed countries)      (developing countries)    research centers and seed banks
                                                                                   Fig. 10-5, p. 210
                      US Agriculture

   Agribusiness
    • Industrialized farming evolved into- big companies take control of ¾
      U.S. food production

   Highly productive
    • 18% nations gross domestic product. 1/5 of all jobs in private sector (
      employs more than any other industry)
    • U.S. produces 17% of world’s grains
   Greatly increased yields under Green Revolution

   Very efficient

   Energy intensive
    Energy Use in US Agriculture

                                                                                17% of total
  4%              2%           6%                         5%                    commercial
                                                                                energy use
 Crops        Livestock   Food processing   Food distribution and preparation

Food production

                                                                     Fig. 10-7, p. 211
               Traditional Agriculture
   Interplanting- several crops on same plot simultaneously

   Polyvarietal cultivation- plot with several genetic varieties
    of same crop

   Intercropping- 2 or more different crops grown at same time on
    a plot
     • Ex- carbohydrate rich grain that uses soil nitrogen and a nitrogen fixing
       plant that outs it back (like a support system or a balancer)

   Agroforestry or alley cropping- crops and tress grown

   Polyculture- many different plants maturing at various times are
    planted together
World Grain Production

                     Fig. 10-17, p. 218
      Causes of Hunger and

   Poverty

   Inequality

   War

   Corruption

   Undernutrition- people who cannot grow or buy
    enough food to meet basic energy needs

   Malnutrition- results from deficiencies of protein,
    calories, and other key nutrients

   Overnutrition- food energy intake exceeds energy use
    and causes excess body fat
    Vitamin A

 Iron and anemia

      Saving Children from
     Malnutrition and Disease
   Immunizations against diseases

   Encouraging breast feeding (except for mothers with

   Prevent dehydration from diarrhea

   Prevent blindness with vitamin A

   Family planning

   Increase education for women
              Consequences of
   Lower life expectancy

   Greater susceptibility to disease

   Lower productivity and life quality

   Obesity and overweight

   Leading cause of premature death

   Serious problem in the US

   Possible solutions
    Environmental Effects of
        Producing Food
   Environmental degradation may
    decrease future food production

   Almost 30% of world’s cropland

   Environmental degradation may limit
    food production in India and China
Major Environmental Effects of
       Food Production

                     Fig. 10-18a,b, p. 220
     Soil Erosion and Degradation

   Land degradation

   Soil erosion: flowing water and wind

   Erosion enhanced by humans

   Gully erosion

   Loss of soil fertility

   Global soil erosion
Soil Erosion on Irrigated

                        Fig. 10-8, p. 212
Gully Erosion

                Fig. 10-9, p. 212
Global Soil Erosion

              Areas of serious concern

              Areas of some concern

              Stable or nonvegetative areas

                                  Fig. 10-10, p. 213
           Soil Erosion in the US

   US soils eroding 16 times faster than forming

   Great Plains lost 1/3 or more of their topsoil

   Reductions in US soil losses since 1980s

   Soils dry out, degrade, and become less fertile

   Natural causes

   Human contributions
   World Desertification

Moderate     Severe        Very Severe

                      Fig. 10-11, p. 214
           Causes and Consequences of

  Causes                             Consequences
                                    Worsening drought
                                    Economic losses
                                    Lower living
Soil compaction                     standards

Natural climate                     Environmental
change                              refugees

                                 Fig. 10-12, p. 215
Salinization and Waterlogging of

   Impacts of irrigation

   Salt accumulation in soils (salinization)

   Salts kill crops and make soils infertile

   Prevention is cheaper than remediation

   Waterlogging: accumulation of saline water
Salinization and Waterlogging in Soils
  Evaporation                                    Evaporation


                                              Less permeable
                                              clay layer

                                                               Fig. 10-13, p. 215
Salinization from Heavy

                      Fig. 10-14, p. 215
Preventing and Cleaning Up Soil

                       Soil Salinization
 Prevention                                Cleanup

 Reduce irrigation                         Flushing soil
                                           (expensive and
                                           wastes water)

                                           Not growing crops
                                           for 2-5 years

 Switch to salt-
 tolerant crops
 (such as barley,                          Installing under-
 cotton, sugar beet)                       ground drainage
                                           systems (expensive)

                                                                 Fig. 10-15, p. 215
        Conservation Tillage

   Soil conservation

   Conservation-tillage farming

    • Minimum-tillage farming

    • No-till farming

            Fig. 10-16a, p. 217
Contour Planting and Strip Cropping

                            Fig. 10-16b, p. 217
Alley Cropping

                 Fig. 10-16c, p. 217

             Fig. 10-16d, p. 217
         Organic Fertilizers

   Animal manure

   Green manure

   Compost

   Crop rotation
        Inorganic Fertilizers

   Commercially available

   Nitrogen

   Phosphorus

   Potassium

   Doesn’t replace organic matter
    Increasing Food Production
   Traditional crossbreeding

   Genetic engineering (Third Green Revolution)

   Genetically modified foods (GMF)

   Expanding the Green Revolution

   Environmental impacts

   Limits of the Green Revolution

   Irrigation

   Limits to expansion of cultivatable land
Tradeoffs of Genetically Modified
                          Genetically Modified Food and Crops
                    Projected                        Projected
                   Advantages                      Disadvantages
   Need less fertilizer                              Irreversible and
                                                     unpredictable genetic
   Need less water                                   and ecological effects

   More resistant to insects,                        Harmful toxins in food
   plant disease, frost, and                         From possible plant cell
   drought                                           Mutations

   Faster growth                                     New allergens in food

   Can grow in slightly salty                        Lower nutrition
                                                     Increased evolution of
   Less spoilage                                     Pesticide-resistant
                                                     Insects and plant
   Better flavor                                     disease

   Less use of conventional                          Creation of herbicide-
   pesticides                                        Resistant weeds

   Tolerate higher levels of                         Harm beneficial insects
   pesticide use
                                                     Lower genetic diversity
   Higher yields
                                                                                Fig. 10-19, p. 221
          Producing More Meat
   Feedlots

   Environmental impacts

   Water use and contamination

   Soil loss from overgrazing

   Cattle methane and soil nitrous oxide: greenhouse gases

   Contamination from animal wastes

   Overgrazing and desertification

   Endanger wildlife

   Sustainable meat production
Overgrazed and Lightly Grazed

                        Fig. 10-20, p. 223
      Efficiency of Converting Grain
            into Animal Protein
                Kilograms of grain needed per kilogram of body weight

 Beef cattle



Fish (catfish
    or carp)                       2

                                                                Fig. 10-21, p. 224
Harvesting Fish and Shellfish
   Fisheries

   Fishing methods

   Aquaculture

   World fish catch

   Overfishing

   Commercial extinction

   Aquaculture (fish farming and ranching)

   Sustainable aquaculture
                                Fishing Methods
                                                                          Spotter airplane

                    Fish farming              Trawler
                    in cage                   fishing

                                                              Purse-seine fishing
                             trawl flap

                                                fish school
                    trawl bag

                         Drift-net fishing
Long line fishing                                              float   buoy

                         lines with

                                              fish caught
                                                 by gills

                                                                                             Fig. 10-22, p. 225
Fish Catch

             Fig. 10-23a, p. 225
           Tradeoffs of Aquaculture
          Advantages                 Disadvantages
Highly efficient                         Large inputs of land, feed,
                                         And water needed
High yield in small
volume of water                          Produces large and
                                         concentrated outputs of
Increased yields                         waste
through cross-
breeding and genetic                     Destroys mangrove forests
                                         Increased grain production
Can reduce over-                         needed to feed some
harvesting of                            species
conventional fisheries
                                         Fish can be killed by
Little use of fuel                       pesticide runoff from
                                         nearby cropland
Profit not tied to price
of oil                                   Dense populations
                                         vulnerable to disease
High profits
                                         Tanks too contaminated to
                                         use after about 5 years
                                                                       Fig. 10-24, p. 226
Solutions: More Sustainable
         More Sustainable Aquaculture

• Reduce use of fishmeal as a feed to reduce depletion
  of other fish

• Improve pollution management of aquaculture

• Reduce escape of aquaculture species into the wild

• Restrict location of fish farms to reduce loss of
  mangrove forests and other threatened areas

• Farm some aquaculture species (such as salmon and
  cobia) in deeply submerged cages to protect them
  from wave action and predators and allow dilution of
  wastes into the ocean

• Set up a system for certifying sustainable forms of
                                                         Fig. 10-25, p. 227
    Effects of Government Agricultural
       Policies on Food Production

   Protecting US agriculture

   Keeping food prices artificially low for consumers

   Subsidies and tax breaks for farmers

   Eliminate government supports?

   Food aid

   Reward farmers if they protect the environment?
   Compete with humans for food

   Invade lawns and gardens

   Destroy wood in houses

   Spread disease

   Invade ecosystems

   Simply a nuisance

   May be controlled by natural enemies

   Humans too often destroy the natural enemies of pests
Spiders: Enemies of Insect Pests

                          Fig. 10-26, p. 227
   Chemicals to kill or control undesirable organisms

   Insecticides

   Herbicides

   Fungicides

   Rodenticides

   Biocides

   Toxicity and use

   Broad- and narrow-spectrum agents

   Persistence
Rachel Carson

         •Pioneer in increasing public
         awareness of the importance
         of nature and threat of
         pollution from pesticides
         •Wrote The Sea Around Us
         about the natural history of
         oceans and how human
         activities were harming them
         •In 1962, published Silent
         Spring about affects of
         •An important contributor to
         the modern environmental
         movement in the U.S.

                          Fig. 10-A, p. 229
        The Case for Pesticides

   Save human lives

   Increase food supplies and lower costs for consumers

   Profitable for farmers

   Work faster and better than alternatives

   When used properly, benefits exceed health risks

   Newer pesticides are safer and more effective than older ones

   Newer pesticides have low application rates
           The Ideal Pesticide

   Kills only target pest

   Doesn’t cause genetic resistance in the target

   Disappears or breaks down into harmless
    components after doing its job

   More cost-effective than doing nothing
    The Case Against Pesticides

   Accelerate genetic resistance in pests

   The pesticide treadmill

   Kill the pests’ natural enemies

   Don’t say put: pollute

   May harm wildlife

   May threaten human health

   How successful are pesticides?
      US Pesticide Regulations

   US EPA has banned some pesticides

   Food Quality Protection Act

   Problems with federal laws on pesticide use and enforcement

   Besides EPA, FDA and USDA also regulate pesticide use

   Exporting banned pesticides from the US
        Alternatives to Chemical

   Adjusting cultivation practices

   Genetic engineering

   Biological control (use of natural predators)

   Sex attractant (pheromone) traps

   Hormones to disrupt the insect life cycle

   Hot water
Genetic Engineering to Reduce
        Pest Damage

                        Fig. 10-28, p. 232
    Integrated Pest Management
   Ecological system approach

   Reduce pest populations to economically tolerable levels

   Biological and cultivation methods first used

   Chemical pesticides are a last resort

   Results in Indonesia

   Pollution prevention and other advantages

   Disadvantages of integrated pest management

   Methods for promoting integrated pest management in the US
    Why is Integrated Pest Management
         Not More Widely Used?

   Requires expert knowledge

   Initial costs may be high

   Hindered by government subsidies

   Opposition from pesticide companies
    Solutions: Sustainable Agriculture

   Slow population growth

   Reduce poverty

   Sustainable (low-input or organic) agriculture

   Increase research on sustainable agriculture

   Establish demonstration projects

   Support with subsidies and foreign aid

   Establish training programs
Sustainable Organic Agriculture
                      Sustainable Organic Agriculture

          More                                          Less
High-yield polyculture                          Soil erosion

Organic fertilizers                             Soil salinization

Biological pest control                         Aquifer depletion

Integrated pest                                 Overgrazing
Irrigation efficiency
                                                Loss of
Perennial crops                                 biodiversity

Crop rotation                                   Loss of prime
Use of more water-
efficient crops                                 Food waste

Soil conservation                               Subsidies for unsustainable
                                                farming and fishing
Subsidies for more
sustainable farming and                         Population growth

                                                                              Fig. 10-31, p. 234
             What Can We Do?
                   What Can You Do?

             Sustainable Agriculture

•Waste less food

•Reduce or eliminate meat consumption

•Feed pets balanced grain foods instead of meat

•Use organic farming to grow some of your food

•Buy organic food

•Compost your food wastes

                                                  Fig. 10-32, p. 234

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