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Download SNC1PL Pests and Pesticides
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Natural ecosystems have high biodiversity Artificial ecosystems have low biodiversity Agro ecosystems (farms) are artificial ecosystems created to maximize the production of one species. To maximize this crop, organisms that compete with, or damage crops (pests) must be regulated Colorado Potato Beetle (Leptinotarsa decemlineata) Pesticides are substances that may be used to kill pests biologically and/or physically. Herbicides kill plants Rodenticides kill rodents Fungicides kill fungus Insectides kill insects Pesticides may be broad-spectrum (affecting many different species) or narrow-spectrum (affecting a limited number of species) Odourless, broad spectrum pesticide derived from the Jicama, Yam, or Mexican Turnip Linked to the development of Parkinson’s Disease (interferes with cellular respiration) Originally added to fishing waters to easily kill fish, which would then float to the surface APPROVED FOR USE BY SOME ORGANIC FARMS Synthetic (made by humans), broad-spectrum pesticide used to kill weeds. Very low persistence (breaks down easily) Works by removing a weed’s ability to grow Derived from bacteria (Bacillus thuringinesis) since 1920. Narrow-spectrum pesticide that is highly toxic to moth and butterfly caterpillars 1) Non-target species: broad spectrum pesticides tend to kill off non target species and predators of pests. Therefore more pesticides must be used to artificially protect crops. 2) Bioamplification: Some pesticides are not soluble in water and tend to be stored in the fat cells of its victims (bioaccumulation). As higher organisms feed on lower trophic levels, the concentration of pesticides builds up causing lethal doses of pesticides to organisms high on the food chain. 1. 2. 3. 4. Put your bags and notebooks on your desk or on the side benches Tuck your chair in Find a spot to stand somewhere in the classroom Only move when Mr. Chawla gives further instructions Hawk Lamprey Perch Algae Hawk Lamprey Perch Algae 3) Pesticide Resistance: Some pests are able to mutate and develop resistance to pesticides over time. This means new pesticides must be created since the old versions may not work anymore (EXPENSIVE!)
