GGRC44H3 Lecture : Lecture 5
Document Summary
Present/future status of world"s soils: 1980s studies: we can feed the world. Un-fao: look to uncultivated lands (esp. in latin america: big soil study: 1990 (global assessment of soil degradation, intensify productivity with technology, reduced; soil depth, water, organic matter=reduced crops, canada/usa: soil conservation programs in ontario oscia. Terracing: countour of land, working with landscape, reduce. Multiple cropping: different various crops on same land erosion: recycle waste/manure: from humans and animals, happens in ontario (not only china) a principle of biodynamic. Agriculture from waste is good to rebuild soil. Agricultural resources: water: water: the life blood of the biosphere, of world"s water to 100 litres; freshwater for humans is one teaspoon, agriculture: approx. 70% of water use: compare: water footprint" of different products, beef, vegetables. Improving efficiency: class: what might be the problem with only thinking about improving efficiency with technology, tax subsidies for water use encourage wastefulness.