A spatially explicit individual-based forest simulator

Individual trees of different species compete for light and space on a one-hectare toric space. Computations are carried out on a yearly time step. Capture and use of both resources (light and space) are species dependent and mediated through a number of parameters related to distinct geometrical and physiological characteristics for each species. A light interception module uses crown optical and geometrical characteristics to compute how much light is available to each tree. Competition for space is monitored by computing at each time step how much surface of each crown envelop is free from overlapping by neighboring crowns and stored as the crown form index. Recruitment and mortality are also governed by species dependent parameters. Mortality is a function of the growth rate. Secondary mortality can occur due to tree fall possibly creating canopy gaps. Recruitment depends on the specific biological cycle of the species. The potential number of offspring of the late successional species (e.g. Lansium domesticum, Shorea javanica or Durio zibethinus) depends on the number of sexually mature adult trees. On the contrary pioneer species have a constant recruitment pressure independent of the actual number of adult trees as they have wind spread or dormant seeds. Actual recruitment is ultimately governed by actual light conditions

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