Know Soil, Know Life Glossary
This glossary is designed for more advanced explorations of soil science terms and words. The words and definitions are from the SSSA Book Know Soil Know Life.
Not finding a word? Try the advanced Glossary of Soil Science Terms. Too advanced? Check out the Young Scientists glossary for introductory words and definitions.
| Term | Description |
|---|---|
| Mesic |
average annual soil temperature is well above freezing, sometimes referred as the corn belt |
| Mesoorganism |
Organism between 0.1 and 2 millimeters. |
| Micronutrient |
Essential elements (Cl, Fe, B, Mn, Zn, Cu, Ni, Mo) nutrient found in plants in the lowest amounts. Also referred to as minor elements. |
| Microorganism |
Organism smaller than 0.1 millimeters (100 micrometers). |
| Micropores |
Pores that are sufficiently small that water within these pores is considered immobile, but available for plant extraction, and solute transport is by diffusion only. |
| Mineralization |
Conversion of an element from an organic to an inorganic form. |
| Mite |
Small, eight-legged invertebrates, many of which are microscopic. |
| Mollisols |
Grassland soils—the Great Plains, Russian steppes. |
| Munsell color system |
A color designation system that specifies the relative degrees of the three simple variables of color: hue, value, and chroma. For example: 10YR 6/4 is a color (of soil) with a hue = 10YR, value = 6, and chroma = 4. See also chroma, hue, value, color. |
| Mycorrhiza (Plural: Mycorrhizae) |
Literally means “fungus roots.” the association, usually beneficial, of specific fungi with the roots of higher plants (adjective form is mycorrhizal). |
| Nematode |
Nonsegmented worm, often microscopic. Some are parasitic on plants but many are normal soil inhabits that feed on fungi and bacteria. |
| Nitrate |
Plant-available form of nitrogen (NO3–). |
| Nitrification |
Biological oxidation (loss of electrons) of ammonium to nitrite and nitrate. |
| Nitrogen Cycle |
Describes the conversion of dinitrogen gas (N2) from the atmosphere through microbes, plants, and animals to soil transformations and back to atmospheric dinitrogen gas. Important microbial processes include biological nitrogen fixation, mineralization, nitrification, and denitrification. |
| Nitrogenase |
Active enzyme involved in biological nitrogen fixation that converts dinitrogen gas (N2) into ammonia (NH3). |
