Food Production and the Environment

Food Security

  • Learning Objectives:
    • Distinguish between food security and food insecurity.
    • Describe the root cause of food insecurity.
    • Distinguish between chronic undernutrition and malnutrition.
    • Describe the harmful effects of overnutrition.
  • Factors influencing food supply: poverty, war and conflict, the COVID-19 pandemic, extreme weather events, and climate change.
  • In economically less-developed countries, people suffer from health problems associated with undernutrition.
  • In economically more-developed countries, others suffer health problems from overnutrition.
  • Food Security Pillars:
    • Availability (supply).
    • Accessibility (ability to grow or purchase).
    • Utilization (how the body makes the most of the nutrients).
    • Stability (ability to obtain food over time).
  • Poverty: The root cause of food insecurity.
  • Food insecurity: Conditions where people live with chronic hunger and poor nutrition, threatening their ability to lead healthy and productive lives.
  • 2050 Projection: Need to feed at least 9.7 billion people, almost half in economically less-developed countries.
  • Challenge: How to feed more people without seriously harming the environment?

Chronic Hunger and Malnutrition

  • Chronic undernutrition (hunger): Not enough food to meet basic energy needs.
  • Chronic malnutrition: Not enough protein and other key nutrients.
    • Economically less-developed countries: diets center on high carbohydrate grains and very little protein (low on the food chain).
    • Economically more-developed countries: Food deserts (no access to fresh food) result in diets high in fat, sugar, salt, and little protein.
  • Lack of Vitamins and Minerals:
    • Almost 2 billion people suffer from a deficiency of micronutrients.
    • Most common deficiencies worldwide:
      • Vitamin A: blindness and death.
      • Iron: anemia (fatigue, susceptibility to infection, risk of maternal death).
      • Iodine: stunted growth, mental retardation, and goiter.
  • Health Problems from Too Much Food:
    • Overnutrition: when food energy intake exceeds energy use and causes excess body fat.
      • Lowers life expectancy.
      • Increases susceptibility to disease and illness.
      • Lowers productivity and life quality.
    • Nearly one in five deaths in the United States from heart disease, stroke, type 2 diabetes, and some forms of cancer.

Food Production

  • Learning Objectives:
    • List the three systems that supply most of the world’s food.
    • Distinguish between industrialized and traditional agriculture; monoculture and polyculture; and organic and conventional agriculture.
    • Explain how the first and second green revolutions have increased crop yields.
  • Today, agriculture uses both high-input industrialized and lower-input traditional methods to produce the world’s food supply.
  • Organic agriculture and genetic engineering address some of the problems in agriculture.
  • Meat consumption as well as fish and shellfish production are on the rise.
  • Three systems supply most of the world’s food:
    • Croplands (rice, wheat, and corn).
    • Rangelands, pastures, and feedlots (meat and meat products).
    • Fisheries and aquaculture (fish and shellfish).
  • Half of the world’s people survive on rice, wheat, and corn, meat and seafood come from only a few species of mammals and fish, violating the biodiversity principle of sustainability.
  • Three major technological advances increased yields in all three systems:
    • Irrigation: artificial methods that supply water to crops.
    • Synthetic fertilizers.
    • Synthetic pesticides.
  • Industrialized/high-input agriculture: heavy equipment, fossil fuel, commercial fertilizer/pesticides, and money (monoculture: growing one to two crops).
    • Food supply vulnerable to disease.
  • Traditional/low-input agriculture: solar energy and human labor to grow a crop that will feed a family with no surplus (polyculture: growing several crops).
  • How does polyculture fulfill the principles of sustainability?
  • Organic agriculture: crops grown without the use of synthetic pesticides and inorganic fertilizers, or genetic engineering; animals raised without hormones or antibiotics.
  • U.S. labeling system:
    • 100 percent organic (or USDA Certified Organic): has undergone certification to meet requirements.
    • Organic: must contain at least 95% organic ingredients.
    • Made with organic ingredients: at least 70% organic ingredients.
    • Natural: have no requirement for organic ingredients.
  • The green revolution increased yields from existing croplands by:
    • planting monocultures of crops genetically engineered or selectively bred for high yields.
    • using large amounts of water, synthetic fertilizers, and pesticides.
    • increasing land use by alternating different crops throughout the year (multiple cropping).
  • Gene Revolutions to Improve Food Supply
    • Crossbreeding through artificial selection (first gene revolution)
      • Centuries-old practice.
      • Takes 15 years or more, varieties remain useful for limited time.
    • Genetic engineering (second gene revolution)
      • Gene splicing is faster and generally less expensive
      • Allows gene transfer from different species
  • Concerns with Genetically Engineered Food
    • Genetic engineering is too costly for use by farmers in economically less-developed countries.
    • While many people are consuming GM foods daily, we know too little about their long-term health effects.
    • There may be unintended harmful genetic and ecological effects of GM organisms released into the environment.
  • The increasing demand for food is being met by increases in production.
  • Meat and animal products such as eggs and milk are good sources of high-quality protein.
  • Meat production now uses feedlots as well as rangelands and pastures.
  • In concentrated animal feeding operations (CAFOs), animals are fed grain, fish meal, or fish oil, which usually contain added growth hormones and antibiotics.
  • Fisheries and Aquaculture:
    • Industrial fishing fleets harvest most of the world’s marine catch of wild fish.
    • Fish and shellfish are also produced through aquaculture—marine and freshwater fish farms in freshwater ponds and rice paddies, or in underwater cages in coastal waters.
    • Most aquaculture raises species that feed on algae or other plants—carp, catfish, tilapia, and shellfish.
    • The farming of meat-eating species such as shrimp and salmon is growing rapidly (more-developed countries).

Environmental Effects of Industrialized Food Production

  • Learning Objectives:
    • Explain why industrialized agriculture can be environmentally and economically unsustainable.
    • Describe why topsoil is important, the harmful effects of degrading topsoil, and how desertification occurs.
    • Describe how soil and water degradation results from excessive irrigation.
    • Describe the benefits and harmful effects of using concentrated animal feeding operations (CAFOs) to produce meat.
    • Describe the benefits and harmful effects of aquaculture.
  • Soil erosion, desertification, irrigation, water shortages, air and water pollution, climate change, and loss of biodiversity may limit future food production.
  • Large inputs of energy are needed to grow, store, process, package, transport, refrigerate, and cook plants and animals.
    • In the United States, 10 units of fossil fuel energy are needed to produce 1 unit of food energy.
  • Industrialized agriculture:
    • uses 70% of fresh water from surface sources and aquifers.
    • degrades and erodes topsoil.
    • accounts for 26% of global greenhouse gas emissions.
    • uses about half of the world’s ice-free land.
  • Topsoil (the fertile top layer of many soils): a significant natural capital component because it stores water and nutrients needed by plants.
  • Topsoil renewal: one of the earth’s most important ecosystem services.
    • Topsoil nutrients recycle endlessly as long as they are not removed faster than natural processes replace them.
  • Soil Erosion:
    • The movement of soil from one place to another by nature and by human activity.
      • Flowing water (the largest cause of soil erosion) carries away soil loosened by rainfall.
      • Wind loosens and blows away topsoil particles—from flat land in dry climates.
      • Farming, deforestation, and overgrazing expose land and hasten soil erosion.
  • Harmful Effects of Soil Erosion:
    • Loss of soil fertility through the depletion of plant nutrients in topsoil
    • Topsoil pollution of surface waters can kill fish and clog reservoirs and lakes.
      • Increased if it contains pesticide residues—biomagnified through food webs.
    • Erosion releases the soil’s carbon content, altering the carbon cycle and adding to atmospheric levels of CO2.
  • Desertification: The process in which the productive potential of topsoil falls by 10% or more.
    • A major threat to food security.
    • Decreases soil productivity.
    • Desertification can be:
      • moderate (10–25% drop in productivity).
      • severe (drop of 25–50%).
      • very severe (drop of more than 50%).
  • Irrigation boosts/lowers farm productivity.
    • Irrigation water has a variety of salts, which leads to soil salinization.
    • Overwatering fields results in waterlogging—this raises the water table and deprives plants of needed oxygen.
  • Fertilizers can pollute groundwater resources and aquatic ecosystems.
  • Agricultural practices release chemicals and greenhouse gases into the air.
  • Clearing and burning forests leads to the loss of natural biodiversity.
  • As fewer varieties of plant and animal species are used in farming, agrobiodiversity decreases.
  • In the United States, about 97% of the food plant varieties available to farmers in the 1940s no longer exist.
  • Limits to the Green Revolution:
    • High cost and high inputs of fertilizer, pesticides, and water.
    • Natural limits prevent plants from taking up more nutrients.
    • Soil salinization and depletion of both underground water supplies (aquifers) and surface water for irrigation.
    • Decreased or degraded land available for agriculture.
    • Climate change–related crop yield reduction, along with droughts and flooding in some areas from rising sea levels.
  • Cheap meat produced by industrialized agriculture has harmful environmental and health costs not reflected in pricing.
  • High amounts of water and energy use, and waste produced.
  • The high use of antibiotics in industrialized livestock production (80% of worldwide antibiotic supply) facilities genetic resistance.
  • Harmful Environmental Effects of Aquaculture:
    • Using fishmeal and fish oil to feed farmed fish can deplete populations of wild fish and can contain (biomagnified) toxins.
    • Loss of mangrove forests and estuaries to fish farms.
    • Dense populations are vulnerable to disease.
    • Large amounts of wastes (may contain pesticides and antibiotics) pollute aquatic ecosystems and fisheries.
    • Farmed fish can escape their pens and mix with wild fish, disrupting the gene pools of wild populations.

Sustainable Pest Management for Crops

  • Learning Objectives:
    • Explain why the natural enemies of agricultural pest species—predators, parasites, and disease organisms—are an important form of natural capital.
    • Describe the benefits and problems of using synthetic pesticides.
    • Summarize the effectiveness of laws and treaties that help protect humans from the harmful impacts of pesticides.
  • Natural enemies control the populations of most pest species.
    • This free ecosystem service is an important part of earth’s natural capital.
  • Humans upset the checks and balances of natural pest control when we clear forests and grasslands, plant monoculture crops, and use synthetic chemicals to kill pests.
  • Classification of Pesticides:
    • According to target: insecticides (insect killers), herbicides (weed killers), fungicides (fungus killers), and rodenticides (rat and mouse killers).
    • Broad-spectrum agents are toxic to beneficial species as well as to pests.
    • Selective, or narrow spectrum, agents are effective against a narrowly defined group of organisms.
    • Pesticides vary in their persistence, the length of time they remain in the environment.
  • Advantages of Synthetic Pesticide Use:
    • Human lives have been saved from insect-transmitted disease (especially malaria).
    • Food supplies are increased by reducing food loss due to pests.
    • Facilitates no-till farming, preventing soil erosion.
    • Crop yields and farming profits increase.
    • Newer pesticides are safer, more effective, and work faster.
  • Disadvantages of Synthetic Pesticide Use:
    • The development of genetic resistance to pesticides.
    • Long-term usage diminishes effectiveness—costing farmers more for less return.
    • Insecticides kill the pest’s natural enemies.
    • Inefficient application causes pollution, affecting wildlife and human health.
    • Pesticide use has not reduced U.S. crop losses to pests.
  • Protective Laws and Treaties:
    • Federal Insecticide, Fungicide and Rodenticide Act (FIFRA)
      • Allows the U.S. EPA, USDA, and FDA to regulate the sale and use of pesticides.
      • Adequate funding has not been provided for effective management and enforcement of FIFRA.
    • Food Quality Protection Act
      • requires the EPA to reduce the allowed levels of pesticide residues in food when effects on children are unknown.
    • Persistent Organic Pollutants (POPs) Treaty
      • international agreement to ban or phase out the use of POPs
  • Alternatives to Synthetic Pesticide Use:
    • Crop rotation/adjusting planting time starves pests/allows enemies to eat them.
    • Polyculture provides homes for pests’ enemies.
    • Implant genetic resistance (through genetic engineering)
    • Biological control
      • Natural pheromones to lure pests into traps or attract natural enemies into crop fields
      • Insect hormones to disrupt their life cycles
  • Integrated Pest Management
    • The overall aim of IPM is to reduce crop damage to an economically tolerable level.
      • Farmers first use biological methods and cultivation controls upon detecting an economically damaging level of pests.
      • They apply small amounts of insecticides only when insect or weed populations reach a cost of damage/pesticide threshold.

Sustainable Food Production

  • Learning Objectives:
    • Describe ways to conserve topsoil.
    • Describe how farmers can use organic fertilizers to restore and maintain soil fertility.
    • Describe ways to prevent and clean up soil salinization.
    • Explain how we reduce the environmental impacts of meat production.
    • Describe ways to make aquaculture more sustainable.
    • List the advantages and disadvantages of organic farming.
  • Protecting Topsoil:
    • Soil conservation by terracing, contour planting, strip-cropping, planting cover crops, and setting up windbreaks).
    • Alley cropping or agroforestry (planting crops in orchards).
    • Conservation-tillage farming (currently requires herbicides).
    • Reducing irrigation dependence; rotating crops/switching to salt tolerant varieties.
    • Growing plants without soil (hydroponics).
    • Identifying and protection erosion hotspots
  • Restoring Soil Fertility:
    • By using organic fertilizers derived from plant and animal materials
      • Animal manure
      • Green manure
      • Compost
      • Biochar
    • By using synthetic inorganic fertilizers containing nitrogen, phosphorus, and potassium
    • By rotating nitrogen-depleting crops such as corn with nitrogen-producing crops such as legumes
  • Reducing Soil Salinization and Desertification:
    • Most solutions to prevent and rehabilitate salinized and desertified soils are costly.
      • Reducing irrigation, using more efficient irrigation methods, and switching to salt-tolerant crops are some solutions.
      • Cleanup involves flushing soil, leaving the field fallow for 2–5 years, and installing underground drainage systems.
    • To restore land suffering from desertification, we can plant trees and other plants that anchor topsoil and hold water.
  • Practicing More Sustainable Aquaculture:
    • Certifications of sustainable practices
    • Open-ocean aquaculture
      • reduces coastal ecosystem damage (mangrove forests, estuaries).
      • improves management of wastes.
    • Recirculating aquaculture systems
      • reduces use of antibiotics.
      • reduces escape of aquaculture species into the wild.
    • Polyaquaculture systems
      • Mini-ecosystems of algae, seaweeds, and farmed fish/shellfish
  • Use organic farming and organic polyculture methods.
  • Shift from using imported fossil fuel to relying more on solar energy for food production.
  • Industrialized farms can use technology to find ways to precisely apply pesticides and fertilizers in smaller amounts.
  • Consumers should learn where their food comes from, how it is produced, and its environmentally harmful effects.
  • Governments should replace subsidies for environmentally harmful forms of industrialized agriculture.

Improving Food Security

  • Learning Objectives:
    • Explain how government subsidies can be used to encourage or discourage sustainable food production.
    • Explain how government and/or private programs can be used to reduce poverty and improve food security.
    • Describe ways to obtain locally grown food.
    • Explain how urban farming can increase food security.
  • The Government’s Role in Improving Food Production and Security:
    • Controlling food prices versus food subsides
    • Providing small business loans to lift people out of poverty
    • Saving children from the health effects of malnutrition and providing food aid
    • Educating farmers in sustainable, organic food production
  • Buy locally grown food and grow more food locally.
  • Participate in community-supported agriculture (CSA).
  • Prevent wasted food by storing and transporting food properly, and reducing waste in restaurants, homes, and supermarkets.
  • Grow more food in urban areas through community gardens, container gardens, and others.