ENV100Y5 Lecture Notes - Lecture 7: Cation-Exchange Capacity, Soil Horizon, Soil Texture
69
ENV100Y5 Full Course Notes
Verified Note
69 documents
Document Summary
A 35 km2 protected wetland: peat soils formed over 8000 years; up to 6m thick. Decomposition releases carbon: interdisciplinary research project studying the influence of climate on carbon balance. Soil is a complex material: mineral matter, organic matter, water, gases, dead/living microorganisms; decaying material, bacteria, algae, earthworms, insects, mammals, amphibians, reptiles, supports plant growth. Soil formation starts with bedrock: parent material = base geologic material of soil, bedrock = continuous mass of solid rock (the earth"s crust, regolith (sediment) = broken-up rock. Weathering = processes that break down rocks: physical (mechanical) = no chemical changes in parent material, chemical = substances chemically interact with parent material, biological = organisms break down parent material. Salt weathering: form of mechanical or physical weathering of rock. Biological weathering: weakening and subsequent disintegration of rock by plants, animals and microbes. Soil formation is very slow: factors that affect soil formation: Biological activity (soil microbes and fauna; decomposition and accumulation of organic matter)
