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3.5 Food Resources. Food Issues MEDC / LEDC. Food Production and Distribution. Imbalance in food distribution. Over 1 billion people are living in poverty and starving in LEDC countries MEDC Average Caloric Intake = 3314 LEDC Average Caloric Intake = 2666 Causes:
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Imbalance in food distribution • Over 1 billion people are living in poverty and starving in LEDC countries • MEDC Average Caloric Intake = 3314 • LEDC Average Caloric Intake = 2666 • Causes: • Unequal distribution • Lack of access to clean water • Poor harvesting / farming practices (overgrazing/ overfishing)
Food Waste 3.5.3 Compare and contrast the inputs and outputs of materials and energy (energy efficiency), the system characteristics, and evaluate the relative environmental impacts for two named food production systems. The systems selected should be both terrestrial or both aquatic. In addition, the inputs and outputs of the two systems should differ qualitatively and quantitatively (not all systems will be different in all aspects). The pair of examples could be North American cereal farming and subsistence farming in some parts of South-East Asia, intensive beef production in the developed world and the Maasai tribal use of livestock, or commercial salmon farming in Norway/Scotland and rice-fish farming in Thailand. Other local or global examples are equally valid. Factors to be considered should include: • Inputs—for example, fertilizers (artificial and natural), irrigation water, pesticides, fossil fuels, food distribution, human labour, seed, breeding stock • System characteristics—for example, selective breeding, genetically engineered organisms, monoculture versus polyculture, sustainability • Socio-cultural—for example, for the Maasai, cattle equals wealth and quantity is more important than quality • Environmental impact—for example, pollution, habitat loss, reduction in biodiversity, soil erosion • Outputs—for example, food quality and quantity, pollutants, soil erosion. FLIPCAST— Introduction to systems thinking CASE STUDY—Biosphere II CASE STUDY—Biosphere II
Aquatic Food Production • Aquatic Food Production: • Food is harvested from high tropic levels due to human preference (ex. salmon). • Photosynthesis is less efficient by producers due to light reflection of water
Terrestrial Food Production • Terrestrial Food Production: • Most food harvested from low tropic levels (producers / herbivores) • Energy conversions less efficient on land
Food Production affects the Environment • Biodiversity • Soil • Water • Air • Human Health
Increasing food production output • GMO- Genetically Modified Organisms • Change genetic make up of living things to make them look, feel, and taste different • Pesticides- chemicals used to kill pest organisms • Herbicides- chemicals used to kill weeds • Fertilizers- chemicals used to grow larger crops • Irrigation- canals used to bring in more water • Antibiotics/ Growth Hormones- used to grow healthier and larger animals
Biodiversity Loss • Loss of grasslands forests and wetland for cultivation • Loss of genetic diversity (wild crops replaced with monocrops)
Soil • Erosion • Loss of fertility • Salinization • Desertification • Increase soil pH
Water • Waste water produced • Aquifer depletion from increased irrigation
Air • Large fossil fuel use in farming equipment causes release of greenhouse gases (CO2, N2O, and CH4) • Pesticide sprays
Human Health • Nitrates in Drinking water • Blue baby • Pesticides • Bacterial contamination of meat (E. coli)
Comparison Pair #1 North American Cereal Farming Asian Subsistence Farming Inputs: lots of human labor, water, sunlight Characteristics: grow only enough to eat to feed family & community, low tech Socio- Cultural: mostly LEDC, poor Environmental impact: maintains biodiversity, reduces pollution Outputs: Usually mixed crops; corn, beans and squash (all in same field) • Inputs: Fertilizers, pesticides, fossil fuels, labor, sunlight, water equipment • Characteristics: Heavy use of fossil fuels, lots of farming technology, monocrops (only one crop) • Socio- Cultural: Fast production, large amounts, lots of waste • Environmental impact: loss biodiversity • Outputs: Air pollution , water pollution, wheat/corn, lots of income ($$)
Comparison Pair # 2 MEDC- Intensive Beef Production LEDC- Maasai Tribal Livestock Inputs: Labor, Cattle feed/ grazing grass Characteristics: large herds of cattle, used as only food source “Nomadic Herding” Socio- Cultural: Cattle are THE source of life (even used as currency) Environmental impact: overgrazing, nomadic behavior Outputs: meat, milk, blood • Inputs: Hormones, antibiotics, labor, cattle feed (corn), breeding stock of cattle • Characteristics: Many cattle in crowded area • Socio- Cultural: Fast production, large quantities, lots of waste/death • Environmental impact: disease, waste • Outputs: Air pollution, water pollution, beef, lots of income ($$)
Comparison Pair # 3 Salmon Farming in Norway Rice-Fish Farming Thailand Inputs: labor, seed Characteristics: fish and rice grown together in same, self sustaining ecosystem (fed by natural food chain) Socio- Cultural: LEDC countries, Environmental impact: reduces waste maintains biodiversity Outputs: rice, fish, income • Inputs: antibiotics, fish food, cages, labor • Characteristics: fish raised in large quantity • Socio- Cultural: MEDC, employs large number of workers • Environmental impact: growth of algae, water pollution • Outputs: salmon, water pollution
Slash and Burn / Shifting Cultivation • Input: Labor, plow, oxen, seed • Characteristics: Tropical forest set on fire to clear the land & ash fertilizes soil. After land is used farmers repeat this process • Socio-cultural: Typically harvested food is sold in community, low population density • Environment: Loss of biodiversity, fertility, ecosystem production decreases • Output: Monocrop, air pollution, income
