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Feeding the world

Feeding the world. Is there enough to nourish everyone?. Overview. World food production is adequate in quantity and quality (nutritional value) to feed the current human population. Modern food problem is largely due to Distribution Issues Poverty in large part of the world.

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Feeding the world

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  1. Feeding the world Is there enough to nourish everyone?

  2. Overview • World food production is adequate in quantity and quality (nutritional value) to feed the current human population. • Modern food problem is largely due to • Distribution Issues • Poverty in large part of the world

  3. Some farmland is lost for food production • Suburban development (e.g., CT where farming has been decreasing for years)

  4. Overview • Increases in food production have been accomplished: • Increasing area in production • Increasing production per unit area

  5. Soils • Definition: • Rock modified by biological, chemical and physical processes such that the material will support rooted plants • How long does it take to make soils? • 1mm per 10 - 40yrs

  6. Soils • To grow crops we need soils. What is soil? ~Weathered rock? • Chemical elements, including organics, required for plant growth • Air and water pass freely through the soil • Should retain water well • Fine clays help retain moisture, chemicals • Sands and coarse particles help with drainage

  7. Soils • Soils are damaged due to: • Removal of natural ground cover • Farming, Deforestation, Overgrazing • Erosion: wind and water • Acidification, excess leaching • Pollution

  8. Soils

  9. Soils

  10. Soils • Agriculture in the 20th century has damaged more than 109 ha of land through erosion and soil loss

  11. Soils • In US • One third of topsoil lost, 80 x 106 ha of land ruined or marginalized for agriculture • Rates of soil erosion are controversial but it seems that since the 1930’s rates have decreased from 17 to 13 tonnes/ha/yr

  12. Soils • Rivers carry 4 x 109 tons/yr of sediment, 75% from agricultural lands; sedimentation rates in coastal waters have increased by factors of 2-5 over the last 150 years (e.g. LIS) • Excess sedimentation wordwide is a problem • In US $500 million/yr dredging expenses

  13. Soils & Agriculture Advances have been made in tilling practices • Contour Plowing: plow perpendicular to the slope. Tests show reduction in erosion from 14.4 tons/ acre to 0.1 ton / acre • No-Till agriculture: currently ca. 100 million acres in US • Terracing

  14. ‘No Till’ Agriculture reduces nutrient losses

  15. Soil Erosion

  16. Terraces • used in traditional cultures • Reduce erosion • Maintain fertility Bali rice paddies

  17. Percentage of Land in Agriculture 9% Africa, 11% N. America, 11% Asia, 20% Europe, 11% World

  18. Land & Agriculture

  19. Land & Agriculture

  20. Land & Agriculture World Grain Production has leveled off Per person production declining?

  21. Land & Agriculture • World Grain Production has leveled due to: •  in production from former USSR? • limits fertilizer effects? • erosion, salinization, lack of irrigation water?

  22. World Food Supply Shrinking?

  23. Food Security, India • In 1950, 51x106 tons food grain • In 1995, 200x106 tons food grain • In 1995, 30x106 tons food grain in surplus • In 1995, 40% of population (>350 million people) were starving • People are too poor to buy the available food!

  24. Food Security • Problem: distribution • Solution: increase local production • Problem: poverty – people too poor to buy available food • Solution: employment, social welfare

  25. Food Security: Can we meet the future demands? • By 2025, we will have to triple irrigated lands • Volume of water will equal the Nile or 10 Colorado Rivers • Water diversion will have competition from providing local drinking water and for local crops • In 2025, use of runoff to increase from 54% to 70% • Destruction of rivers, fisheries and aquatic species

  26. Genetically Modified (GM) Crops • Placement of foreign genes into crops (or other organism) • Enhance production and growth under usually deleterious climates or conditions • Disease and insect resistance

  27. Genetically Modified (GM) Crops • Panacea or Plague????? • NAS panel (2002) says no strong evidence of environmental damage • Evidence for gene spreading (e.g., GM genes in taco products) • Evidence for allergic responses in humans • Growth genes in cereal – shrimp – human allergy and immune response • Who owns the resources?????

  28. Food production depends on soil, water and energy supplies - all are stressed!

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