5.02 vocab
C horizon
1. the layer of a soil profile immediately below the B horizon and above the bedrock, composed of weathered rock little affected by soil-forming processes. C horizon in Science Expand. C horizon. In ABC soil, the lowermost zone, consisting mainly of unconsolidated, weathered rock fragments.
Granular Structure
A ped is a soil particle. There are five major classes of structure seen in soils: platy, prismatic, columnar, granular, and blocky.
A horizon
A soil horizon is a layer generally parallel to the soil crust, 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.
R horizon
A soil horizon is a layer generally parallel to the soil crust, 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.
Soil sampling
If a shovel or a spade is used, dig a V-shaped hole to sample depth (4-6''), then cut a thin slice as shown on the right. Mix soil cores for each sample in a clean, plastic bucket. If the bucket has been used to hold fertilizer or other chemicals, wash it thoroughly before using it for soil samples.
O horizon
O horizons: are soil layers with a high percentage of organic matter. Typically within a woodland area there are three distinct organic layers: one of leaves, pine needles and twigs (Oi); underlain by a partially decomposed layer (Oe);and then a very dark layer of well decomposed humus (Oa).
Pore space
Porosity or pore space refers to the volume of soil voids that can be filled by water and/or air. It is inversely related to bulk density. Porosity is calculated as a percentage of the soil volume: Bulk density x 100 = % solid space.
Porosity
Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0 and 100%.
Soil layers
Soil Horizons (layers): Soil is made up of distinct horizontal layers; these layers are called horizons. They range from rich, organic upper layers (humus and topsoil) to underlying rocky layers ( subsoil, regolith and bedrock).
Soil Structure
Soil structure refers to the arrangement of soil separates into units called soil aggregates. An aggregate possesses solids and pore space. Aggregates are separated by planes of weakness and are dominated by clay particles. Silt and fine sand particles may also be part of an aggregate.
Soil Texture
Soil texture is an important soil characteristic that drives crop production and field management. The textural class of a soil is determined by the percentage of sand, silt, and clay. Soils can be classified as one of four major textural classes: (1) sands; (2) silts; (3) loams; and (4) clays.
Soil pH
The soil pH is a measure of the acidity or alkalinity in soils. pH is defined as the negative logarithm (base 10) of the activity of hydronium ions (H+ or, more precisely, H.
Ideal pH for vegetable gardens
Vegetable Garden Soil pH Range Squash, Winter 5.5 to 7.5 Strawberry Plants 5 to 7, but optimum is 6.0 to 6.8 Sweet Corn 5.5 to 7.0 Sweet Potatoes 5.6 to 6.5
Water holding capacity
Water holding capacity is the total amount of water a soil can hold at field capacity. Sandy soils tend to have low water storage capacity. Sub-soil constraints (acidity, hardpans etc.) can prevent crops accessing water in the subsoil.
Loam
a fertile soil of clay and sand containing humus.
Lime
a white caustic alkaline substance consisting of calcium oxide, obtained by heating limestone.
Clayey
a. A fine-grained, firm earthy material that is plastic when wet and hardens when heated, consisting primarily of hydrated silicates of aluminum and widely used in making bricks, tiles, and pottery. b. A hardening or nonhardening material having a consistency similar to clay and used for modeling. 2.
Sandy
covered in or consisting mostly of sand.
Silty
sand, sediment, silt. Examples from the Web for silt Expand. The flathead chub is found in silty water and often is the predominant species in streams that have high turbidity.
Sulfur
the chemical element of atomic number 16, a yellow combustible nonmetal.
B horizon
the layer of a soil profile immediately below the A horizon, containing deposits of leached material. B horizon in Science Expand. B horizon. In ABC soil, the second and middle zone, characterized by an accumulation of soluble or suspended organic material, clay, iron, or aluminum.
Permeability
the state or quality of a material or membrane that causes it to allow liquids or gases to pass through it.
