8 A Model of Stand Dynamics for
Holm Oak-Aleppo Pine Forests
Miguel A. Zavala
8.1 Introduction
Understanding the mechanisms controlling forest species dynamics and
composition is a fundamental issue in silviculture and plant ecology (Oliver
and Larson 1990; Crawley 1997). Over the last few decades a growing literature on ecophysiology, population biology and ecosystem ecology has contributed to the empirical. expertise developed by practical forestry during the
last century. As a whole these disciplines have documented some of the most
important processes that take place in forest ecosystems at different levels of
biological organization, from leaf physiology to ecosystem function. Nevertheless, there is a rather limited understanding of how species differences
scale from physiology to whole plant performance and how these whole
plant processes interact with competition to determine stand dynamics and
composition.
Mediterranean-type ecosystems have been frequently used for the study of
plant physiological adaptations to water stress (Rambal 1984; Tenhunen et al.
1987), ecosystem-level processes (Kruger et al. 1983; Roda et al. 1990) and
more recently to address issues relevant to population ecology (Keeley 1991;
Espelta et al. 1995). For this reason, these systems are an attractive scenario
for integrating ecological processes across levels of biological organization.
In this chapter I discuss the role of modelling in relating regional forest
dynamics and composition to stand and individual level processes. I also introduce two different modelling approaches that predict forest composition,
each calibrated from data gathered at two different scales of observation (the
stand and the individual). The first approach consists of a correlational
probabilistic model that has been calibrated with stand data from forest inventories and that provides a statistical description of forest structure across
the landscape. The second approach uses an analytically tractable simulator
of stand dynamics, calibrated from experimental data, to explain regional
forest composition in terms of the population ecology of individuals.
Ecological Studies, Vol. 137
Ferran Roda et al. (eds) Ecology of Mediterranean
Evergreen Oak Forests
© Springer-Verlag, Berlin Heidelberg 1999
Holm Oak-Aleppo Pine Forests
Miguel A. Zavala
8.1 Introduction
Understanding the mechanisms controlling forest species dynamics and
composition is a fundamental issue in silviculture and plant ecology (Oliver
and Larson 1990; Crawley 1997). Over the last few decades a growing literature on ecophysiology, population biology and ecosystem ecology has contributed to the empirical. expertise developed by practical forestry during the
last century. As a whole these disciplines have documented some of the most
important processes that take place in forest ecosystems at different levels of
biological organization, from leaf physiology to ecosystem function. Nevertheless, there is a rather limited understanding of how species differences
scale from physiology to whole plant performance and how these whole
plant processes interact with competition to determine stand dynamics and
composition.
Mediterranean-type ecosystems have been frequently used for the study of
plant physiological adaptations to water stress (Rambal 1984; Tenhunen et al.
1987), ecosystem-level processes (Kruger et al. 1983; Roda et al. 1990) and
more recently to address issues relevant to population ecology (Keeley 1991;
Espelta et al. 1995). For this reason, these systems are an attractive scenario
for integrating ecological processes across levels of biological organization.
In this chapter I discuss the role of modelling in relating regional forest
dynamics and composition to stand and individual level processes. I also introduce two different modelling approaches that predict forest composition,
each calibrated from data gathered at two different scales of observation (the
stand and the individual). The first approach consists of a correlational
probabilistic model that has been calibrated with stand data from forest inventories and that provides a statistical description of forest structure across
the landscape. The second approach uses an analytically tractable simulator
of stand dynamics, calibrated from experimental data, to explain regional
forest composition in terms of the population ecology of individuals.
Ecological Studies, Vol. 137
Ferran Roda et al. (eds) Ecology of Mediterranean
Evergreen Oak Forests
© Springer-Verlag, Berlin Heidelberg 1999