Soils

Ploughing and drainage make soils more aerobic. This increases the rates of nitrogen fixation, nitrification, and the decomposition of dead organic matter.

Adding fertilisers and organic matter

Increases the fertility of soil because water is a limiting factor on growth

The use of heavy machinery or high livestock densities, especially when the soil is wet, causes soil to become compacted. This reduces aeration and makes waterlogging more likely.

Controlling soil pH helps to ensure nutrients are soluble but not too easily leached.

Soil particles removed by wind or water.

The vegetation will be eaten faster than it can grow, increasing the exposure of the soil and the risk of erosion.

Minerals, organic matter, water, air

Important for dissolved nutrients and is a heat sink

macronutrients such as nitrogen, phosphorus, and potassium, present in ionic form mainly as nitrates, phosphates, and potassium ions

bacteria return nutrients to the environment by breaking it down

organisms that spend all or a portion of their lifecycle within the soil or on its immediate surface

fertile soils is usually in the range 5.5 to 7.0 which is the range of tolerance for most plants and other soil biota.

bacteria that convert atmospheric nitrogen into ammonia

Bacteria that change dissolved ammonia into nitrite compounds or nitrites into nitrate compounds.

fungi that surround plant roots and help plants obtain water and minerals

recycle nutrients within the ecosystem by breaking down non-living organic matter

used to determine textural classes of soil from the percentages of sand, silt, and clay in the soil

Relative amounts of the different types and sizes of mineral particles in a sample of soil.