ES101 Lecture Notes - Lecture 3: Shortgrass Prairie, Overgrazing, Permafrost
Document Summary
Tropical grassland: savanna: type of grassland with warm temp, 2 dry seasons, abundant rain rest of year, also large herds of animals. Animals have evolved eating habits that limit competition: ex. Raised cattle has made savanna become desert bc cattle need more water, and their poop dry up and kill grass. Temperate grassland: cold winters, hot summers, deep and fertile soil to grow crops and raise cattle, precipitation is sparse (some areas in southern ontario) Windy and evaporation is rapid causing fires. Fires burn plants but not root for new life. Plowing breaks up soil transforming grassland to desert. Have become breadbaskets that produce gain (long-grass) and sagebrush desert is bc of overgrazing (short-grass) Polar grassland/tundra: covered in ice and snow, limited precipitation, mainly moss. Permafrost: frozen layer of soil that forms not far below the surface when the water there freezes (longer than 2 years) Many insects thrive in this region which feed birds.
