EESA01H3 Lecture Notes - Lecture 7: Chernozem, Soil Science, Soil Classification
Document Summary
Soil is crucial to life on earth, a key resource. Environmental interface of minerals, air, water and living organisms. Principle medium of plant growth, supplies food. Serves as an engineering medium: urban sustainability. Likely that thru intensive agriculture, fertility and viability of soil can diminish. Complex mixture of organic and inorganic matter, a wide diversity of organisms: bacteria, protists, fungi, invertebrates. Dynamic natural bodies having properties from the combined effect of climate and biotic activities, as modified by topography, acting on parent material over periods of time. A specific soil depends on where it came from: the soil forming factors. A slow and gradual transformation of rock (termed: parent material) into smaller and smaller pieces. Change occurs due to mechanical or chemical weathering. Physical weathering: disintegration of rocks into smaller and smaller pieces. Agents of physical/mechanical weathering: temperature changes, abrasion from wind, small particles in air, plants and animals. Chemical weathering: decomposition of rocks due to biogeochemical processes.
