ES290 Lecture Notes - Lecture 3: Urban Revolution, Sustainable Agriculture, Plant Breeding
Document Summary
***test emphasizes the stress on the agroecosystem from over use, fertilizers and pesticides and the. Lesson 3: agriculture loss of productive land to urbanization. **canada= decrease in # of farms but increase in over all size and productivity. Yield increase also comes from improvements in crop production through plant breeding (i. e. new varieties of maize and wheat) ***side effects of nitrates from chemical fertilizers= contamination of drinking water and harming sh/aquatic life. Use of chemicals to control pests however have improved yields (i. e. herbicides, insecticides and fungicides) Greatest change with fertilizers occurs in developing countries. Negative effects of pesticides= contaminate surface/ground water and harm the health of farm workers + killing of predators of target species = upsetting the balance = leading to further outbreaks (also resistance**) Includes improvements to tools/cooperation which = a more reliable food supply: nomadic hunting: shift from nomadic wanderings to a more sedentary lifestyle and more intensive use of natural foods.
