Abstract

HERNANDEZ-MARTINEZ, Abel Joseph et al. Use of density management diagrams for mixed stands in the state of Michoacan. Rev. mex. de cienc. forestales [online]. 2024, vol.15, n.82, pp.89-115.  Epub Apr 26, 2024. ISSN 2007-1132.  https://doi.org/10.29298/rmcf.v15i82.1450.

Density guides (DG) are fundamental tools for silviculture, because they allow a better distribution of the growth space within the stand. The objective of this work was to construct and apply two DGs derived from a potential model (PM) and an exponential model (EM) for the thinning simulation. Two forest management objectives were tested: (1) To conserve, and (2) To change the proportion of species in the stand. Information from 1 346 minimum forest management units (MFMUs) with mixed species was used. The MFMUs were projected within the DGs in terms of the Stand Density Index (SDI), with respect to a maximum SDI (SDI max ). An MFMU was then randomly selected to deal with the aftereffects of thinning according to the two objectives aforementioned. The SDI max were 883 (PM) and 800 (EM), on the basis of which the Langsaeter growth zones were defined as a percentage: 70 % imminent mortality, 40 % constant growth, and 20 % free growth. The thinning simulations indicated that in both 1 and 2, a greater tree and basimetric area removal was projected when using the PM DG than with the EM DG. The two DGs have implications for the final harvest projection due to the structure and definition of the SDIs.

Keywords : Mixed forests; density index; exponential model; potential model; thinning simulation; growth zones.