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Lester R. Brown, Plan B 3.0: Mobilizing to Save Civilization (New York: W.W. Norton and Company, Earth Policy Institute, 2008). 4. Emerging Water Shortages 5. Natural Systems Under Stress 6. Early Signs of Decline. Lester R. Brown,. 4. Emerging Water Shortages.
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Lester R. Brown, Plan B 3.0: Mobilizing to Save Civilization(New York: W.W. Norton and Company, Earth Policy Institute, 2008) 4. Emerging Water Shortages 5. Natural Systems Under Stress6. Early Signs of Decline
Lester R. Brown, 4. Emerging Water Shortages The global water deficit is the result of demand tripling over the last half century. The link between water and food is strong. As water tables fall, the energy required for pumping rises. Lakes are disappearing on every continent and for the same reasons: excessive diversion of water from rivers and overpumping of aquifers. It takes 1000 tons of water to grow 1 ton of wheat worth $200. It takes 4533 gallons of water to grow 2700 cal to feed you one day. Although spreading water shortages are intimidating, we have the technology needed to raise water use efficiency, thus buying time to stabilize population size.
5. Natural Systems Under Stress Lester R. Brown, Where ever the land is, the health of the people cannot be separated from the health of the land itself. Lowdermilk noted about the Middle East, “here erosion had done its worst….if the soils had remained, even though the cities were destroyed and the populations dispersed, the area might he re-peopled again and the city’s rebuilt, but now that the soils are gone all is gone.” The thin layer of topsoil that covers the planet’s land surface is the foundation of civilization. Accelerating soil erosion or the last century can be seen in the dust bowls that form as vegetation is destroyed and wind erosion soars out of control. Twentieth-Century population growth has pushed agriculture onto highly vulnerable land in many countries. Desertification is the process of converting productive land to wasteland through overuse and mismanagement.
6. Early Signs of Decline Lester R. Brown, Hunger is the most visible face of poverty. As with illiteracy, ill health and poverty are closely linked. Everyone on the planet shares this “body burden” of toxic chemicals, but infants are at greater risk because they are in the highly vulnerable formative stage of early development. Access to land is a prime source of social tension. Expanding world population has cut the grain land per person in half, from 0.23 ha in 1950 to 0.10 ha in 2007. (~ 0.247 ac or 104 ft x 104 ft area) As the health of the land deteriorated, so did health of the people dependent on it. Advancing deserts are also displacing people, squeezing expanding populations into an ever smaller geographic area. In an age of increasing globalization and economic integration, the functioning of the global system and thus the well-being of individual states depends on a cooperative network of functioning nation state’s.
The thin layer of topsoil that covers the planet’s land surface is the foundation of civilization. This soil, typically six inches or so deep, was formed over long stretches of geological time as new soil formation exceeded the natural rate of erosion. As soil accumulated over the eons, it provided a medium in which plants could grow. In turn, plants protect the soil from erosion. Human activity is disrupting this relationship.
Water erosion also takes a toll on soils. This can be seen in the silting of reservoirs and in muddy, silt-laden rivers flowing into the sea.
Earth Surface Area Entire Planet 510.0x10^6 sq km. 100% Oceans 361.0x10^6 sq km. 71% Continents 148.9x10^6 sq km. 29%
Total Land area 148.9 million km2 = 100% deserts, wastelands, urban areas, ice-covered = 41.5% forests (including savannas) = 27.1% pasture and rangeland = 21.8% croplands 14.4 million km2 = 9.6% croplands 1.44 billion hectares (3.56 billion acres) With ~6.7 billion people (1/1/2008) = 0.22 ha/person (0.55 acre/person) http://home.alltel.net/bsundquist1/la2.html
Soil Is a Precious Resource Imagine earth as an apple. Slice the apple into four quarters: ¾ is water and ¼ is land Take that ¼ that is land and slice it in half: 1/8 is inhospitable to people (i.e. polar ice caps, mountains, etc.) 1/8 is land that people can live on Take that 1/8 of land and slice it in half: 1/16 is too cold, too wet, too rocky, or too dry to grow food 1/16 could produce food for humans and animals Take that 1/16 and slice it in half: 1/32 is covered in highways, houses, buildings and other manufactured structures 1/32 is all that is left to grow food, right? Wrong!!! Carefully cut the peel off the 1/32 section. This represents the surface of the earth and is all the soil that is used to grow crops and food for humans and animals. This thin peeling is what supports the approximately ~6.7 billion people on earth. This thin peeling is a diminishing, precious resource that must be conserved.
Is this a sustainable way to use crop biomass? C ? “ A nation that destroys its soil, destroys itself.” Franklin D. Roosevelt, 1937
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C View the plant as carbon! (~ 45% C) Plant Power Carbon capture Carbon storage Energy storage Food source Energy source Soil carbon input Environmental benefits Quality of Life
C Agronomists and Resources! Photosynthesis Sun Water Energy Capture Energy Use Agronomists Respiration Air Soil
Food C Feed Fiber Fuel Ecosystem Services Sun Air Our Resources Water Soil
C Carbon is the “C” that starts “C”onservation!
C Nature’s Interdependent Tri-Cycles: Water, Carbon, Nitrogen, Carbon is the “Lord of the Rings”. H2O N Mg Mn Cu K P Ca Zn Na Cl Bo Fe S Mo
C Carby Carbon CO2 CO2 Keep your carbon footprint small! CO2 CO2