The capacity of soil to carry machinery without significant damage to the soil or the vegetation growing on it.

The process whereby plants lose water by evaporation of liquid water at the surface of the stomatal cells, the water vapour diffusing out through the leaf via the stomata openings.

Technology Readiness Level. According to the EC 9 levels are distinguished: 1: basic principles observed; 2: technology concept formulated; 3: experimental proof of concept; 4: technology validated in lab; 5: technology validated in relevant environment (industrially relevant environment in the case of key enabling technologies); 6: technology demonstrated in relevant environment (industrially relevant environment in the case of key enabling technologies); 7: system prototype demonstration in operational environment; 8: system complete and qualified; 9: actual system proven in operational environment (competitive manufacturing in the case of key enabling technologies; or in space).

Levels of the food chain. The first trophic level includes photosynthesizers that get energy from the sun. Organisms that eat photosynthesizers make up the second trophic level. Third trophic level organisms eat those in the second level, and so on. It is a simplified way of thinking of the food web. In fact, some organisms eat members of several trophic levels.

A crop grown under a nurse crop and intended to become either a non-harvested crop grown in between two main crop seasons or become a main crop itself in a next season.

Soil properties that show change and respond to use and management of the soil, such as soil organic matter levels and aggregate stability. This is a narrower term than dynamic soil properties which encompasses all changes on the human time scale including those induced by natural disturbances or cycles.

Soil properties that show little change over time and are not affected by use and management of the soil, such as mineralogy and particle size distribution.

The extent of land used for farming, including arable land, permanent grassland, permanent crops and other agricultural land such as kitchen gardens, but excluding unused agricultural land, woodland and land occupied by buildings, farmyards, tracks, ponds, scrub land, etc.

The aerated region of soil above the groundwater table. The unsaturated zone is characterized by a downward movement of leachate.

Amount of water (mm) needed to return moisture conditions of a soil back to field capacity.