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Grassland and Rangelands CHAPTER 10
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Fig. 12-16, p. 291 TRADE-OFFS Genetically Modified Crops and Foods Projected AdvantagesProjected Disadvantages Irreversible and unpredictable genetic and ecological effects Need less fertilizer Need less water More resistant to insects, disease, frost, and drought Harmful toxins in food from possible plant cell mutations Grow faster New allergens in food Can grow in slightly salty soils Lower nutrition Increase in pesticide- resistant insects, herbicide- resistant weeds, and plant diseases May need less pesticides Tolerate higher levels of herbicides Higher yields Can harm beneficial insects Less spoilage Lower genetic diversity
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Rangelands-unfenced grassland that supply forage for vegetation.
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Fig. 10-15, p. 225 NATURAL CAPITAL DEGRADATION Major Causes of the Destruction and Degradation of Tropical Forests Basic CausesSecondary Causes Not valuing ecological services Roads Cattle ranching Crop and timber exports Fires Logging Government policies Settler farming Tree plantations Poverty Cash crops Population growth Cattle ranching Tree plantations Logging Cash crops Settler farming Fires Roads
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Some Rangelands Are Overgrazed (1) Important ecological services of grasslands – Soil formation – Erosion control – Nutrient cycling – Storage of atmospheric carbon dioxide in biomass – Maintenance of diversity – Rangelands, if not overgrazed, are less destructive than feedlots.
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REVIEW: What were the causes and remedies for the great dust bowl in the United States CAUSESSOLUTIONS
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Restoration of Grazing Lands What is a riparian area?
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We Can Manage Rangelands More Sustainably (1) Rotational grazing Replant barren Suppress growth of invasive species – Herbicides – Mechanical removal – Controlled burning – Controlled short-term trampling by livestock
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CLASSWORK You are a member of a lobby group that is appearing before congress to testify about genetically modified foods. (GMF’s) You may argue for OR against. Compose a well written paragraph providing four (4) valid supporting sentences that supports your stance. PAGE 287 IS A GREAT RESOURCE.
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Vocabulary review. Potable Municipality Anthropogenic Flavr savr tomato Per capita
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