Dyson writes: > To stop the carbon in the atmosphere from increasing, we only need to > grow the biomass in the soil by a hundredth of an inch per year. Good > topsoil contains about ten percent biomass, [Schlesinger, 1977], so a > hundredth of an inch of biomass growth means about a tenth of an inch > of topsoil. Unfortunate, then, in the U.S., we are losing 1.8 billion tons of soil a year.
http://soils.usda.gov/sqi/concepts/soil_organic_matter/som_manage.html ..and that even under ideal agricultural conditions, it takes about 3 years to form one tenth of an inch of topsoil: http://home.alltel.net/bsundquist1/se3.html#A ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
