Root sampling methods
Overview
Interest in root sampling was first stimulated on an ecological scale by testing soil water availability to plants in 1960(Gardener). Methods have been developed since that are able to develop both rough estimations and almost exact representations of root biomass. Rhizodeposition is a key factor in Plant establishment and these sampling methods become useful when gathering information on plant nutrient allocation and overall health.
Root Length Equation
Where R = total length of the root, N = # of intersections between the root and straight lines, A = area of the sampled rectangle, and H = total length of the straight lines. The root length equation was created by E.I. Newman after he recognized that absorption of nutrients and water from the soil depends on root length and surface area rather than overall biomass. (Newman) Newman used various mathematical and ecological equations to derive this one specifically for complicated root systems so direct counting and measurement under a microscope can be avoided. It holds importance as it was one of the first offering a quicker, more accurate approach to counting roots and fine root hairs.
Uses for Root Sampling
Root samples are useful for many agricultural, ecological, and educational purposes.
Destructive Sampling Methods
The Harvest Method
Monoliths
Root-Ingrowth
Non-destructive Sampling Methods
Rhizotrons
Minirhizotrons
Sources
Gardener, W. R. “DYNAMIC ASPECTS OF WATER AVAILABILITY TO PLANTS.” SOIL SCIENCE, vol. 89, no. 2, Feb. 1960, pp. 63–73., journals.lww.com/soilsci/Citation/1960/02000/DYNAMIC_ASPECTS_OF_WATER_AVAILABILITY_TO_PLANTS.1.aspx. Newman, E. I. “A Method of Estimating the Total Length of Root in a Sample.” Journal of Applied Ecology, vol. 3, no. 1, 1966, pp. 139–145. JSTOR, www.jstor.org/stable/2401670.