Environmental Science 1021F/G Lecture Notes - Lecture 5: Biomimetics, Environmental Health, Biological Pest Control
25 Feb 2016
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Document Summary
100 species (1%) cause 90% of the damage. Pesticides: types: insecticides block reproduction, airways, nervous system to kill insects, herbicides disrupt plant growth and metabolism meant to harm plants not to kill but to suppress the growth, fungicides: attack fungus, rodenticides: kill rodents. Crop rotation, vary planting times, plant diversity, hedgerows. Sulphur, lead, arsenic, mercury problem b/c poisonous to humans. Nicotine sulphate, pyrethrum, rotenone naturals=come from plants (cid:0) second generation. Synthetic organic compounds (eg ddt), broad- and narrow-spectrum, persistence reduction, some natural persistence reduction major problem is they persist in soil for a very long time even after say ddt was banned it still is present in soil. Second generation try to create pesticides that breakdown in the soil. Reduces that persistence has been the goal broad spectrum = roundup, partnered with gmo crops and will kill any plant that hasn"t been modified to resist narrow spectrum = opposite, would only affect one specific species.
