Lesson 2 – Soil
... – Occurs in dry desert and grassland areas where the surface is so dry, that water is transferred from deep in the ground to the surface ...
... – Occurs in dry desert and grassland areas where the surface is so dry, that water is transferred from deep in the ground to the surface ...
Lindsey`s Basic Guide to the Soil Orders of Canada Disclaimer: This
... Lindsey’s Basic Guide to the Soil Orders of Canada Disclaimer: This is an extreme generalization of soil orders of Canada. More information about each order can be found in the Canadian System of Soil Classification and the Soil Management Guide. However, I have found that these resources can be dif ...
... Lindsey’s Basic Guide to the Soil Orders of Canada Disclaimer: This is an extreme generalization of soil orders of Canada. More information about each order can be found in the Canadian System of Soil Classification and the Soil Management Guide. However, I have found that these resources can be dif ...
The soil forming factors
... horizon, where the parent material is unaltered and retains its original properties. The parent material accounts for most of the physical (e.g., texture) and chemical characteristics. ...
... horizon, where the parent material is unaltered and retains its original properties. The parent material accounts for most of the physical (e.g., texture) and chemical characteristics. ...
Relative-age dating
... Pinedale vs. Bull Lake Pinedale moraines ~ 21 – 15 ka Bull Lake moraines ~ 130 – 100 ka ...
... Pinedale vs. Bull Lake Pinedale moraines ~ 21 – 15 ka Bull Lake moraines ~ 130 – 100 ka ...
GLACIAL EROSIONAL FEATURES
... Soil Profile = Pedon – vertical cuts made into the soil to expose its layers or horizons Soil Zones (Horizons) = the soil profile; many of the horizons may have subdivisions 1) O (organic) horizon - surface-litter layer; consists of fresh & decaying organic matter (freshly fallen leaves, twigs, anim ...
... Soil Profile = Pedon – vertical cuts made into the soil to expose its layers or horizons Soil Zones (Horizons) = the soil profile; many of the horizons may have subdivisions 1) O (organic) horizon - surface-litter layer; consists of fresh & decaying organic matter (freshly fallen leaves, twigs, anim ...
Soil horizon
A soil horizon is a layer generally parallel to the soil surface, whose physical characteristics differ from the layers above and beneath. Each soil type usually has three or four horizons. Horizons are defined in most cases by obvious physical features, chiefly colour and texture. These may be described both in absolute terms (particle size distribution for texture, for instance) and in terms relative to the surrounding material (i.e., ""coarser"" or ""sandier"" than the horizons above and below). The differentiation of the soil into distinct horizons is largely the result of influences, such as air, water, solar radiation and plant material, originating at the soil-atmosphere interface. Since the weathering of the soil occurs first at the surface and works its way down, the uppermost layers have been changed the most, while the deepest layers are most similar to the original parent material.Identification and description of the horizons present at a given site is the first step in soil classification at higher levels, through the use of systems such as the USDA soil taxonomy or the Australian Soil Classification. The World Reference Base for Soil Resources lists 40 diagnostic horizons. Soil scientists often dig a large hole, called a soil pit (usually several meters deep and about a meter wide) to expose soil horizons for study.The vertical section exposing a set of horizons, from the ground surface to the parent rock, is termed a soil profile. Most soils, especially in temperate climates, conform to a similar general pattern of horizons, often represented as ""ideal"" soil in diagrams. Each main horizon is denoted by a capital letter, which may then be followed by several alphanumerical modifiers highlighting particular outstanding features of the horizon. While the general O-A-B-C-R sequence seems fairly universal, some variation exists between the classification systems in different parts of the world. In addition, the exact definition of each main horizon may differ slightly – for instance, the US system uses the thickness of a horizon as a distinguishing feature, while the Australian system does not. It should be emphasised that no one system is more correct – as artificial constructs, their utility lies in their ability to accurately describe local conditions in a consistent manner. Also, many subtropical and tropical areas have soils such as oxisols or aridisols that have very different horizons from ""ideal"" soil, or no horizons at all.