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19. Food Production

19. Food Production supplementary ie. (mostly)not in text, but see: sec.14.10,14.11, 14.12(4 th ed.). Feeding the World.

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19. Food Production

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  1. 19. Food Production supplementary ie. (mostly)not in text, but see: sec.14.10,14.11, 14.12(4th ed.)

  2. Feeding the World Population: 1965 - 3.5 billion 2000 - 6.0 billion 2050 ~10.0 billion (est.) 1998(millions): 137 born - 53 die = 84 gain (rising) Average life expectancy = ~65 years Earth's population growing >1.5%/yr (NA=0.8%, Malaysia=2.3%) 1 bl Oil = 6 billion Joules=1000kg corn = 125kg beef

  3. Doomsday Prophets or Savants ? In~1800(population ~1 billion)Thomas Malthus (economist) wrote "The power of population is infinitely greater than the power in the earth to produce subsistence for man" and "… the passion between the sexes is necessary and will remain". In 1973(population ~3.5 billion) Paul Ehrlich (environmental activist) warned of "… famines of unbelievable proportions" and feeding 6 billion "... is totally impossible in practice"

  4. March 2008 Analysis • CBC feature • Of 6 billion people in the world, 1 billion are obese and 1 billion are starving • Redistribution is needed!!

  5. World Food Requirements WHO estimate = ~2200 Cal/person/day 6 x109 x 2 x 103 = 12 x 1012 Cal/day Food production: 1965: ~2360 Cal/person/day 1995: ~2740 Cal/person/day Supply estimated to exceed demand until 2010 AD Why are 1billion people in the world malnourished > >>>>Distribution = Politics www.nationalgeographic.com/ features/2000/population/planet

  6. Wow! Why Worry? 1 North American farmer can produce food for 100 people. Food costs(% of income): W. Europe = >30% Elsewhere = ?!?! NA = ~15%(Canada = $6200/family/yr, ie.~11%) Crop yields(bushels/acre): Corn(US) - 25(1800)>110(1980)>130(1990) Wheat(England) - 10(1600)>75(1980) Rice(Japan/Korea/Taiwan) - 4X(1950>1990)

  7. Food comes from the Land < 4 billion acres* worldwide used for production of food( > 0.8 acre/person). * Dropping ~2%/yr By 2000 ~5 million acres(India + China) had been degraded so impossible to reclaim, eg. erosion, overgrazing, deforestation, urban 'development' (subSahara Africa, Amazon rain forest, even southwestern Ontario). Just use more fertilizer; $40/acre would increase yield 50%(= 2 billion acres). Cost = $160 billion + pollution.

  8. Distribution of Water in/on the Earth’s Crust LocationVolume(mi.3)% Oceans Saltwater lakes Fresh water (easy) Ground(<0.5 mi) Lakes Rivers Fresh water(hard) Antarctic ice Ground(>0.5 mi) Arctic ice + glaciers 317,000,000 25,000 1,000,000 30,000 300 6,300,000 1,000,000 680,000 325,000,000 97.5 0.3 2.5 (2 x1018 tons) Removal/yr=1000mi3

  9. Water…LKFs (little known facts) Annual withdrawal (world-wide): 1900 – 600 km3 2000 – 3800 km3 World-wide use of annual replaceable fresh water: in 2000 – 54% by 2025 – 70%(90% in underdeveloped countries) ~70% used in agriculture(irrigation – often inefficient)

  10. In Canada..the Living is Easy! See:•worldwater.org •unesco/water/water_links •nationalgeographic.com/ngm/0209

  11. Water, Water, Everywhere and….. Human body(av) 'excretes' ~2.2L/day needs 'to drink' ~1.5L/ day (also food, metabolism). 10% of world population has adequate potable water. Unclean water/sanitation kills ~3 million people/yr (40,000 children/day). In NA we flush down-the-drain 50,000L/person/yr

  12. Water properties • Water acts to moderate Earth’s Temperature • Heat req’d to melt snow and evaporate liq. • High heat capacity: 1cal/gram/oC • Unique in that solid is less dense than liquid at 4oC: (ice floats!)

  13. Water Cycle • Moderates the planet

  14. Water in the USA...(trivia?) Daily use(L)/personDirect(potable!): drinking/cooking -7; bathing - 35; dishwashing -14; flushing toilets - 80; laundry – 35; swimming pools/lawns - 85; other - 90 Indirect: industrial - 3800; irrigation(agriculture/recreation) - 2150; municipal(non industrial) - 550 Total = ~6900 (direct - 380; indirect - 6500) Annual withdrawal = 2X net natural resupply , eg. the Ogallala reservoir under 8 midwest states has dropped from 58  8 ft 'thick' since 1930.

  15. Water Trivia It takes this much water to produce: 800L - 1kg vegetables 13000L - 1 steak 80L - 1L gasoline 30,000L - 1 ton paper 100,000L - 1 ton steel 2,400,000L - 1 ton 'rubber') (1 auto = ~300kg of steel) Most is recycled or 'dumped'(pollution!)

  16. Water – World Supplies UN minimum requirement per person for drinking/washing/cooking = 50L/day or ~1000m3/yr A water-stressed country has less than 2000m3/yr/ person of renewable fresh water: in 2000: 508 million in 31 countries, by 2025: 3 billion in 48 countries,eg. India,China(?)

  17. In Canada it’s Everywhere! OOPS! water-level in Great Lakes drops ~1.2m in last 15 yrs

  18. How Nature corrects itself • Record snowfalls of 2008 Winter are expected to produce a 1 foot rise in the average water level in the Great lakes • In a year, 25% of the problem from the last 15 years is corrected • 1” of rain ~ 1 foot of snow

  19. It has to melt! • Some lost by sublimation

  20. Not so fast……….. • Only net water gain to Great Lakes if source of snow is not “the lake effect” • El Nina in Pacific is good : cools NA and moisture evaporates from Ocean- net gain in water levels for NA

  21. Water in Canada Great lakes holds 20% of the world’s ‘fresh’ water ! But …75% of population, 80% of municipal consumption 90% of industry is American 60% of water runs north into Arctic and ‘unavailable’ Livestock operations in Ontario/Quebec alone produce manure = sewage from 100 million humans Water related illnesses ~10,000/yr; deaths ~ 10/yr Cost to health care system ~ $300 million/yr

  22. Great lakes: chemical “hot spot” • 1969 River fire in Cleveland

  23. 1972: GL Water Quality accord • PM Trudeau and Pres. Nixon, alarmed by 1969 fire on Cuyahoga River, sign on

  24. 1978 Upgrade • US /Canada agree to “restore and maintain the chemical, physical and biological integrity of the waters of the Great Lakes Ecosystem” • Commit to rid GL’s of “persistent toxic substances”-ie those that linger and potentially poison food sources

  25. Biennial Reports • Started in 1981-still going • 1987: emphasis placed on importance of human and aquatic ecosystem health • 43 “areas of concern”

  26. 2008 Centre for Disease Control • Report commissioned by the IJC (oversees issues of GL management) • 25 “areas of concern” • Outbreaks of Minimata disease: includes Cerebral Palsy due to Hg poisoning in Thunder Bay, Collingwood, Sarnia, Cornwall

  27. Source of Mercury • Chlor-Alkali Plants: use Hg in making Cl2 and NaOH. Started in 1894 • 4 cities had large plants (1949-95). 742 tons released • Electrolysis of salt water: (Hg) used as an electrode • 2Cl- oxidized (LEO) to Cl2. OH- from reduction (GER) of water . H2 also formed.

  28. Oxidation and reduction • 2H2O------------------>>H2 + 2OH- • 2Cl- ------------------------>> Cl2 (g) • Chloride ion loses electrons, LEO • H+ ion in water gains electrons GER • Chlorine and OH- produced • Na+ is spectator ion (no change)

  29. Chlor Alkali plants • New tech is available, but not Ohio, Wisc.

  30. Gov’ts reluctant to admit problems • Health Canada knew in 1990’s • No public report-leaked in 2000 • Gov’ts fear lawsuits and expensive cleanups • “there is a reluctance in both US and Canada to admit that there are ANY effects of pollutants on fish, wildlife and human health”

  31. Vital Processes in Food production Photosynthesis for carbohydrate production Nitrogen fixation by plants leads to protein synthesis Plants also biosynthesize fatty acids: Canola etc.

  32. We, and the Earth, need our Nitrogen 'Fix' " The control of all life forms depends on fixed nitrogen to form protein." Inert nitrogen(N2) must be converted to chemically active species, eg. nitrates, ammonia, that can be used by plants and animals to make amino acids/ protein. N2 = :N N: = Inert gas N2 H2 O2 NO32- nitrate NH3 (NH4+) ammonia(-ium)

  33. Nitrogen Fixation - au Naturel • High energy of lightning + O2 NO  NO2 + H2O  nitric acid (HNO3) = 'acid rain'• Clover/alfalfa/soy beans(legumes) have N2 fixing bacteria in their roots(nodules). Can add 100lbs/ acre in one year. About equal amounts(1 billion tons/yr each) • Once fixed, the activated nitrogen can be recycled through dead/decaying organic matter. Humans cannot 'fix nitrogen' and must consume plants/animals to obtain their requirements.

  34. Nitrogen Fixation - in the Lab The(Fritz)Haber Process(~1910) - Nobel prize 1918 N2(g) + 3H2(g) 2NH3(g) First developed for explosives! By 1880s it was recognized that 'active nitrogen compounds' would be necessary as fertilizers to 'feed the world'. By 2000 ammonia is one of the 'top ten' chemicals produced in the world. #6 in USA, at: 20 million tons/yr BUT using energy = 300 million barrels of oil

  35. Plant Nutrients Non-mineral: C(CO2), H/O(H2O) *Primary: (N)nitrogen, (P)phosphorus, (K)potassium Secondary: (Ca)calcium, (Mg)magnesium, (S)sulfur Trace: boron, chloride, copper, iron, manganese, molybdenum, sodium, zinc, (nickel, vanadium) * can be obtained 'naturally' from manure, guano (bird 'droppings'), bone/fish meal

  36. Fertilizers (N, P, K) - the Big Three Nitrogen/Phosphorus/ Potassium % of N, P2O5, K2O = the 3 #s on the box/bag eg. 5 - 10 - 5 (manure = 0.5 - 0.3 - 0.5) As soluble salts, easily assimilated by the plants but easily leached away and not recoverable Can be quick/slow release Can be complete(all three); straight(one of the three)

  37. Nitrogen (Ammonia / Nitrates) Now almost exclusively by the 'Haber process' Sometimes in the form of liquid/'anhydrous' ammonia (gas, bp.-33oC) but easier/less dangerous as solids/salts. Combined with: Carbon dioxide: (urea - H2NCONH2) Acids: sulfuric (ammonium sulfate - (NH4)2SO4) nitric (ammonium nitrate - NH4NO3) phosphoric (ammonium phosphate - (NH4)2HPO4 Natural sources exhausted / too expensive after ~1950, eg.'Chilean saltpeter'(NaNO3) and 'guano' (Chile/Peru)

  38. Nitrates - too much Bang, too many $$ ? *Ammonium nitrate (NH4NO3) Are we hooked? For how many more decades can we afford the high costs of production (non-renewable energy) and nitrate pollution(non-accountable). *Commonly used as an explosive, eg. World War I, Oklahoma City, 1995 and elsewhere

  39. Phosphorus (Phosphates) Recognized in early 1800s, first in Europe, that 'phosphate' was a critical for plants. After skeletons from battlefields were 'used up', larger supplies were required and in more soluble form, so; Ca3(PO4)2 + 2H2SO4 Ca(H2PO4)2 + 2CaSO4 superphosphate also from: phosphate rock + phosphoric acid Largest deposits in Florida and Morocco (2/3 world supply!). Estimated to last for 30 - 40 yrs; then under Atlantic Ocean off Carolinas.

  40. Phosphate Pollution • Food for blue-green algae (cyanobacteria) : summer 2007 • Fertilizers, detergents enter natural waters

  41. Potassium Used as cation(K+), thus any soluble salt will do. Most common form is potassium chloride (KCl). World class deposits developed in: > Germany, before World War I > USA, eg. Carlsbad, NM > Canada(Saskatchewan, 200m thick & 1.5 km below ground); buy shares(?) in Potash Corp

  42. The Future……. • What are your views on • (i) the best Energy sources (and why) • (ii) solution to pollution

  43. Global Environment • Some necessary steps • Population control: reduce/stabilize overall E and food demands • Nuclear power: Clean-low level radioactive waste buried deep in the ground (its origin); no C emissions. Oil has max 100 years left. • Make clean technology financially attractive (gov’t initiatives/grants)

  44. The problem with David Suzuki • Refuses to acknowledge the reality of nuclear power as the future • France (highest ~60% nuclear) has cleanest air in Europe • Wind/solar/wave/biomass etc.OK for off grid applications, but not practical for constant large urban needs

  45. Some positive signs • Ont Gov’t plans new nuclear power facility • Alberta considers nuclear power option despite “tar sands” resources • 1 barrel of oil used to produce 2 barrels in Tar sand project (CBC feature March 2008) • Huge CO2 emitter. Nuclear is the solution

  46. But……..some big negatives • Alberta tar sands: world’s largest oil resource outside Saudi Arabia • BUT..requires a lot of Energy to extract it (~ 1 barrel of oil to produce 2 ) • AND-massive environmental destruction

  47. Environmental damage due to Tar Sands projects • Deforestation • Tailing ponds

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