GEOG 2500 Lecture Notes - Parent Material, Weathering, Pedogenesis
Document Summary
Plants provide physical support, a rooting medium, water and nutrients in solution, and are part of the parent material. Soils are described in terms of factors rather than processes, the five factors are biota, topography, climate, parent material, and time. Our focus is on processes to help us understand mechanisms of soil formation. Parent material(consolidated bedrock or fragmented bedrock/glacial till) is broken down via physical and chemical weathering. The purpose of physical weathering is to release minerals. Physical weathering breaks down smaller rocks into larger rocks. Chemical weathering involves chemical rxns, it is the decomposition of rock involving chemical alteration. It destroys primary minerals and produces secondary ones. Physical weathering of limestone when limestone is created, it is a mineral. This has to do with its speed of weathering. The molecules in qtz are held together very tightly due to strong bonds. There are no holes in there at a microscopic level. Most quartz in the tropics has been dissolved.
