GEOG 1220 Chapter Notes - Chapter 8: Consumer Choice, The Home Depot, Canadian Forest Service
Document Summary
Forest covers roughly 31% of earth"s land surface. Trees are autotrophs, create their own food through photosynthesis. For photosynthesis to take place you need : an amenable temperature, air (to exchange carbon, hydrogen, oxygen and nitrogen, light (the energy source for photosynthesis, soil (the source for mineral nutrients, water (needed for a variety of reasons) Nutrients required in large amounts are macronutrients: nitrogen, phosphorous, potassium, magnesium, calcium and sulphur. Nutrients required in small amounts are micronutrients: iron, manganese, zinc, copper, boron, chlorine, and molybdenum. Water is needed for several reasons: used in photosynthesis, acts as a solvent, dissolving mineral constituents from particles in the soil, transports chemicals inside of the tree, provides support for cells (maintains turgidity) Cohesion the attraction between water molecules than serves to draw additional water into the xylem: important part of the biogeochemical cycle, bringing water from the atmosphere to the ground and from the ground to the atmosphere.