Presentation is loading. Please wait.

Presentation is loading. Please wait.

Food and Agriculture. MAJOR FOOD SOURCES Three crops deliver majority of world’s nutrients: Corn, Wheat, & Rice = 60% of human caloric intake Potatoes,

Similar presentations


Presentation on theme: "Food and Agriculture. MAJOR FOOD SOURCES Three crops deliver majority of world’s nutrients: Corn, Wheat, & Rice = 60% of human caloric intake Potatoes,"— Presentation transcript:

1 Food and Agriculture

2 MAJOR FOOD SOURCES Three crops deliver majority of world’s nutrients: Corn, Wheat, & Rice = 60% of human caloric intake Potatoes, barley, oats and rye are staples in cool, moist climates. Cassava, sweet potatoes, and other roots and tubers are staples in warm wet climates. Our Food Systems: 1) Crop lands 2) Range-land & 3) oceanic fisheries

3 ~ 30,000 identified species of plants that are edible 3,000 tried as crops, 150 species cultivated 14 crops species provide most of the world’s food! USA, AUSTRAILIA, CANADA, NEW ZEALAND largest exporters of grain. WHAT ARE WE EATING?? 2/3 of the world survives on grains because they cannot afford to purchase meat!

4 Industrial Agriculture– large amounts of fossil fuels (energy), water, fertilizers, & pesticides.  Mostly developed nations; 25% of all crop land Plantation Agriculture (form of Industrialized) – large monoculture plantations who sell crops to developed countries.  Practiced in tropical developing nations; cash crops INDUSTRIALIZED (High Input) TRADITIONAL (Low-Input) Traditional Subsistence (low input)– uses human labor and draft animals to produce food for family survival. Practices shifting cultivation & nomadic herding.  44% of worlds people (developing); often tropical areas Traditional Intensive – increase input of energy to produce food to sustain family and produce a modest income.  small inputs of fertilizers, fossil fuels, & irrigation AGRICULTURALPRACTICESAGRICULTURALPRACTICES

5 Green Revolution 1 st Green Revolution – began in 1950’s mostly developed countries 2 nd Green Revolution – end of the 60’s mostly developing countries PROS: 1) Farming more land – GETTING HIGHER YIELDS! Process: 1)Monocultures 2)Selectively bred or genetically engineered to get a 3)Large inputs of fertilizers, pesticides, & water High input agriculture uses 8% of world’s oil output!!

6 Genetic Engineering Genetically Modified Organisms (GMO’s) Contain DNA possessing genes borrowed from unrelated species. Can produce crops with pest-resistance and wider tolerance levels. Opponents fear traits could spread to wild varieties, and increased expense would largely hurt smaller farmers. 70% of all processed foods in NA contain transgenic products. Farmers use methods of crossbreeding through artificial selection to develop genetically improved crops & livestock

7 Benefits & Costs of Genetically Modified Foods There is a growing controversy over the increasing use of genetically altered crops. Is it “ Frankenfood ”?? Need less fertilizers & water Resistant to insects and disease Withstand drought Grow faster (higher yields) Freeze resistant Reduce food allergens Introducing new allergens Need less pesticides Pesticide resistant genes passed to weed varieties Causing rapid evolution of pests Raising food production prices Irreversible genetic & ecological impacts BENEFITS COSTS

8 FOOD PRODUCTION IN THE UNITED STATES Food production in US is now large scale agribusiness. 2% US Pop are farmers; 9% of US Pop involved in Agriculture Business US supplies 17% of the world’s grain with only 0.3% of the world’s farm labor force ENERGY EFFICIENCY 10 units of nonrenewable fossil fuels (coal, oil, nat.gas) are needed to put 1 unit of food energy on the table 1 unit of human labor input supply at least 1 unit of food energy on the table (up to 10 units) Industrial PracticeTraditional Practice Most grain in the US is used to feed livestock

9 Interplanting Techniques for Traditional Agriculture Polyvarietal Cultivation – plot is planted with several varieties of the same crop. Intercropping – two or more different crops are grown at the same time on a plot (ex. Grains that need excess nitrogen grown with legumes that put nitrogen back into the soil system) Agro-forestry (alley cropping) – crops and trees are planted together (serve as erosion protection/ wind breaks) Polyculture – complex form of intercropping where many different plants mature at various times during the year. Traditional farmers in developing countries produce 25% of the world’s food

10 BENEFITS OF POLYCULTURE 1) Less need for fertilizers 2) Protection from erosion 3) Reduces pesticide use 5) Economic stability The various plants will use different amounts of nutrients 4) Less need for irrigation The variety of plants will use various amounts of water and root will grow to different depths The soil is covered with crops year round (vegetation decreases erosion) Weeds cannot compete with the variety of plants; provides habitat for natural predators of pests Plant diversity can survive bad weather; and crop failure

11 SUSTAINABLE AGRICULTURE Soil Conservation Managing Topography Contour Plowing - Plowing across slope to slow flow of water. Strip Farming - Planting different crops in alternating strips along land contours. Terracing - Shaping land to create level shelves of earth to hold water and soil.

12 Soil Conservation Providing Ground Cover Annual row crops cause highest rates of erosion because they leave soil bare for much of the year. Leave crop residue after harvest. Plant cover crops after harvest.

13 Soil Conservation Reduced Tillage Minimum Tillage - Chisel plow Conservation Tillage - Coulter (Disc) No-Till - Drilling Often farmers using conservation tillage must depend relatively heavily on pesticides. Traditional tillage helped control weeds and pests.

14 NUTRITION AND FOOD SUPPLIES World food supplies have more than kept up with human population growth over the past two centuries. 1950 - 2.5 billion people - average daily diet was less than 2,000 calories/person. 2001- 6.0 billion people - world food supply can provide more than 2,500 calories/person. SO…Is there a problem?

15 Chronic Hunger - Undernutrition About 1 in 6 people in the developing world are considered chronically hungry. People consume less calories then are needed for healthy metabolitic functions 200 million children impacted each day Can lead to permanently stunted growth, mental retardation, and other developmental disorders. Are more susceptible to infectious disease (which kills one and four children in developing countries)  Measles, diarrhea

16 Risk of Inadequate Nutrition

17 MALNUTRITION People who consistently live on grains and lack the protein and other key nutrients. Marasmus Marasmus – (Greek meaning to waste away) occurs when the diet is low in both calories and protein  Most victims are children who have mal-nurished mothers who are breast feeding or who do not get enough food after they are weaned. Kwashiorkor Kwashiorkor – (W. African dialect meaning displaced child) is a severe protein deficiency occurring in infants and children ages 1-3, whose mothers give birth again and are unable to breast feed both. Two most common nutritional deficiencies:

18 Micronutrient Deficiencies Iron deficiency Iron deficiency is a common dietary imbalance in the world. Leads to anemia. Increases risk of death from hemorrhage in childbirth and affects development.  Red meat, eggs, and green vegetables are all good sources of iron. Most widespread deficiencies involve: Vitamin A, Iron, Iodine Vitamin A deficiencies can lead to blindness and premature death (due to increased risk of infectious diseases).

19 OVER NUTRITION?? Leading cause of preventable deaths after smoking. Causes heart disease, cancer, stroke, and diabetes.

20 Meat and Milk Meat and Milk distribution highly inequitable. More developed countries make up 20% of world population, but consume 80% of meat and milk production. 60% of production occurs in lesser developed countries. 90% of grain grown in NA is used to feed livestock.

21 Seafood Seafood is an important protein source. Since 1989, 13/17 major fisheries have declined or become commercially in-viable. Between 1970-1990, number and average vessel size of world fishing fleet doubled. Now have twice the capacity needed to extract total annual sustainable harvest. Catching $70 billion cost $124 billion.  1/4 animals considered by-catch. (sea turtles, sharks, dolphins)

22 COMMERCIAL FISHING PRACTICES

23 SALMON FARMING PRACTICES

24 Money vs. Sustenance? CASH CROPS Grown sold or traded in large scale markets Many provide non- food products (rubber plantations, coffee & tea plantations) SUBSISTENCE Used directly by the farmer or sold locally where the food is used in the community NO ECONOMIC PRESSURE


Download ppt "Food and Agriculture. MAJOR FOOD SOURCES Three crops deliver majority of world’s nutrients: Corn, Wheat, & Rice = 60% of human caloric intake Potatoes,"

Similar presentations


Ads by Google