Consisting of or containing large quantities of fine fractions, particularly of silt and clay. A fire that consumes organic material and burns into the underlying soil itself, for example, a peat fire. Applies in some deepwater rice areas of southern Vietnam. A term describing the consistency of a moist soil that offers distinctly noticeable resistance to crushing but can be crushed with moderate pressure between the thumb and forefinger. The process by which certain nutrient elements in a soil are converted from available form to unavailable form essential for plant growth, being converted from a soluble or exchangeable form to a much less soluble or to a nonexchangeable form.
Examples are potassium, ammonium, and phosphorus fixation.
Conversion of available nitrogen to insoluble or unavailable nitrogen. A preservative or chemical used to keep plants for subsequent study. The ammonium in soil that cannot be replaced by a neutral potassium salt solution. A breeding line that continues to breed true to type and does not segregate. That phosphorus which has been changed to an unavailable form as a result of reaction with the soil.