Trees often die gradually because their neighbours deprive them of resources. Death through resource deprivation underpins self-thinning theory and is very well understood; it is included in all Dynamics Global Vegetation Models used to explore how vegetation affects the global carbon cycle. Sporadic death arising from disease, herbivores, fires, earthquakes, windstorms etc is much less easy to characterise but has profound consequences for forest carbon fluxes. We developed a framework for quantifying the effects of disturbance processes (i.e. death not arising from competition) on forest dynamics. The approach uses permanent plot data to parameterise simulation models. We used it to show the profound effects that disturbance has on every aspect of forest carbon cycling in New Zealand1. We have recently used a similar approach to quantify disturbance effects in US forests2. A paper exploring how mortality varies across the whole of Spain provides an essential component for developing similar models for European forests3.
References
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Coomes, D.A., Holdaway, R. J., Kobe, R. K., Lines, E. R., & Allen, R. B. (2012) A general integrative framework for modelling woody biomass production and carbon sequestration rates in forests. Journal of Ecology, 100, 42-64