The mycorrhizal symbiosis provides absorbing surfaces of much smaller diameters than roots, with consequent advantages, as we have illustrated. In pines, only diarch and tetrarch roots (i.e., those of relatively large diameter) appear to be morphogenetically capable of becoming mother roots ( Wilcox, 1968), and hence of long-distance, exploratory growth, illustrating a trade-off necessitated by existing root system design. Glass and Siddiqi (1984) observed that under K limitation, shoot K remained constant while root concentration declined markedly, indicating that K stored in the root cortex had been transported to maintain shoot K concentrations. The root cortex may serve as a short-term reservoir for nutrient storage. For example, larger diameter roots may be able to withstand greater soil impedence before buckling ( Whitely et al., 1982). Most likely, other root functions or anatomical constraints limit the minimum diameter of roots. The results of our simulations indicated that, unless root longevity is strongly tied to root diameter, average lifetime root efficiency increases continuously with decreasing diameter.
Miller, in Resource Physiology of Conifers, 1995 B Discussion Provided several engineering examples to illustrate the use of the solve features. Told how the Minerr function can be used in place of the Find function if Mathcad is not finding a solution. ▪ĭiscussed the built-in variables TOL and CTOL. ▪Įmphasized the rules of using Given, Find, Maximize, and Minimize. Introduced Solve Blocks and showed how they can be used to find solutions to multiple unknowns using multiple equations. ▪īriefly introduced the two solution methods used by the polyroots function (LaGuerre and Companion Matrix Methods). Introduced the polyroots function and showed how it can be used to solve for all the roots of a polynomial equation. ▪Įncouraged the use of a plot to help define the initial guess values for the root function. Showed how the root function can be used with an initial guess prior to using root, or how two guesses can be included as arguments in the root function. Introduced the root function and showed how it can be used to solve for a single variable with a single function.
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