The following conclusions could be made:If for volume table construction, the form factor (f), instead of the volume (v), is used as the dependent variable, better results are obtained.It matters little whether f is estimated from the diameter (d), or from d and height (h) together.Estimating v (or, if more convenient, the so-called form height fh) from d only, on the other hand, leads to much greater inaccuracies.Estimating v of f`g (g = basal area) from h only is most inaccurate.From an accuracy point of view graphical and mathematical methods must be considered equivalent.In actual practice, f can, for most measurements of standing timber, be derived with sufficient accuracy from a smoothing of f on d or from a mathematical solution with the aid of f = a + b log d 1,3 . One should however expect deviations of the f of a stand from the regression line, of up to 10 %.f can be much better estimated by using the regression equation f = a + b1 log d 1,3 + b, log d 6 + b 3 log h. Then the deviations of stands are < 3 % (dx = d at x meter height).The data investigated indicate that close initial spacings and medium to heavy thinnings lead to relatively high f values.The error caused by using f with g as the stand f, is negligible.It is not likely that the functions found will also apply to other tree species.
|Qualification||Doctor of Philosophy|
|Award date||17 Apr 1959|
|Place of Publication||Wageningen|
|Publication status||Published - 1959|
- larix kaempferi
- forest stands