Modeling individual tree mortality for Austrian forest species

Mixing of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) enhances structural heterogeneity, and the effect increases with water availability

“…Combinations of high light-use efficient species with more shade tolerant species capable of high light absorption have been shown to increase light-use efficiency and light absorption of mixtures compared with monocultures (Kelty, 1992;Binkley et al, 2013;Forrester et al, 2012). This may also explain the higher carrying capacity in terms of beech density in mixed plots (Pretzsch and Biber, 2016), probably linked to lower mortality rates (Condés and Río, 2015), since beech tree mortality is often due to competition for light (Monserud and Sterba, 1999;Ruíz-Benito et al, 2013).…”

Durée de vie et mortalité des vieux chênes: une approche empirique combinée à une modélisation pour un appui à leur gestion dans le sud de la Suède

“…For practical purposes, total mortality has been viewed as the sum of regular internal mortality due to competition and senescence (Franklin et al, 1987;Shugart, 1987) and irregular external mortality due to exogenous disturbance agents like wind, drought, insect outbreaks, and fires (Demchik and Sharpe, 2000;Naumenko, 1949;Pedersen, 1999;Shugart, 1987). Under natural conditions, the probability of a regular mortality varies over tree's lifespan with higher mortality in early years, relatively "safe" mid-ages, and somewhat higher probability of death at the end of its lifespan (Monserud and Sterba, 1999). A decrease in tree density over a stand's "lifespan" lowers the importance of competition-related regular mortality (Silvertown and Charlesworth, 2001).…”

Un modèle générique des effets de l’éclaircie et de la densité des peuplements sur la croissance des forêts, la mortalité et l’accroissement net

“…By definition density independent mortality (dB di /dt, Eq. (7)) does not change as a function of c. For spruce stands mortality has been shown to be higher for very small and very big trees (Monserud and Sterba, 1999), i.e. slow growing stages (in terms of absolute growth rate) of stand development, and is therefore modeled to be a function of the net increment (dB/dt) relative to its maximum over the stand development (dB/dt max )…”

“…A number of competition indices have been developed for this purpose, resulting in distance-dependent and distance-independent tree growth models (e.g. Hynynen et al, 2005;Monserud and Sterba, 1999;Siitonen et al, 1999;Sterba and Monserud, 1997). For parameterization of these empirical models for local to national applications, data sets ranging from research trials to national forest inventories have been used (Hasenauer, 2006).…”