Glossary of Irrigation Terms

Magnetic flow meters (sometimes called electromagnetic or mag meters) are a flow measurement technology used in applications where a highly accurate measurement of volumetric flow of a liquid is required. In simple terms, as liquid is moved through an induced voltage the meter can measure flow, liquid velocity and the rate of flow. They can only measure liquids that conduct electricity.

The pipe used to carry water from the chosen water source (i.e. an irrigation lake or well) to the irrigation system itself. The mainline will than carry water through the irrigation system to the points of delivery. In high pressure systems the pipe will probably be made of PVC. 

A unique set of environmental conditions applying to a specific area. Factors which help to create a microclimate include the soil type, the wind, the sunlight available and how much shade there is. Microclimates can occur naturally or can be designed into a landscape.

A type of centrifugal pump which combines features of axial and radial pumps. Water pressure within the pump is generated by a combination of centrifugal force and the lifting action of the pump impellers. Mixed flow pumps generate a high flow rate and high water pressure at the point of discharge.

The difference between the amount of moisture present in the soil and the amount of water the soil is actually capable of holding, once gravitational forces have drained it. The latter is referred to as the field capacity of the soil. 

A device placed in the soil of an area which is being irrigated. It measures the amount of water present in the soil at the root zone, and this figure can then be used to vary the amount of water being delivered through irrigation. Moisture sensors can be stationary or portable. Also known as a moisture meter. 

A pump which takes water in and then pushes it through two or more impellers mounted in a single shaft. Each stage of the pump is made up of an impeller, a diffuser and return guide vanes within a single casing. As the water is fed from impeller to impeller the pressure increases.