Nomenclature
Nomenclature
Every term of the guide, set under its initial.
Terms: 25
A
- AggregateAn aggregate is a small crumb of soil particles held together by organic matter, fungal threads, roots and minerals. Stable aggregates create the pore spaces...
- AgroforestryAgroforestry is the deliberate combination of trees or shrubs with crops or livestock on the same land. The trees add deep roots, leaf litter, shelter and ye...
C
- CompactionCompaction is the squeezing together of soil particles that destroys pore space and makes soil dense and hard. It reduces infiltration, aeration and root gro...
- Cation exchange capacityCation exchange capacity is a measure of how many positively charged nutrient ions, such as calcium, magnesium and potassium, a soil can hold on its clay and...
- Cover cropA cover crop is a crop grown mainly to protect and improve the soil rather than for harvest. It shields the surface from rain and wind, feeds soil life throu...
D
E
G
H
I
L
M
P
R
S
- SubsoilSubsoil is the layer beneath the topsoil, usually lighter in colour, lower in organic matter and denser. It stores water and nutrients and is where deep root...
- Soil horizonA soil horizon is a distinct layer in a soil profile, set apart from the layers above and below by colour, texture, structure or composition. Horizons form o...
- Soil profileA soil profile is the vertical section from the surface down to the underlying parent material, showing all of its horizons in order. Digging a pit or taking...
- Soil organic matterSoil organic matter is all the living and dead organic material in soil, from fresh residues and roots to stable humus. It underpins structure, nutrient supp...
- Soil structureSoil structure is the arrangement of soil particles into aggregates and the pores between them. Good structure lets roots, water and air move freely, holds m...
- Soil textureSoil texture is the relative proportions of sand, silt and clay in a soil. It affects drainage, water holding, nutrient retention and how easily the soil com...
- Soil pHSoil pH is a measure of how acidic or alkaline the soil is, on a scale where 7 is neutral, lower values are more acidic and higher values more alkaline. It i...
- SalinitySalinity is the concentration of soluble salts in soil. When it is high, plants struggle to take up water even when the soil is moist, so crops look drought-...
- SodicitySodicity is a condition in which a large share of the soil's exchangeable cations is sodium. It makes clay particles disperse, so the soil seals, crusts and ...
T
- TopsoilTopsoil is the uppermost layer of the soil profile, richer in organic matter, roots and living organisms than the layers below. It is the most productive lay...
- TerraceA terrace is a level or gently sloping step built into a hillside to shorten the slope and slow runoff. Well-built terraces can reduce erosion substantially ...