The current structure and parameterization of PDG-Arena present several limitations in fully capturing the complexity of mixed forest ecosystems. One significant limitation is the assumption of homogeneous soil water availability across the stand. This simplification overlooks the spatial variability of soil properties and moisture levels, which can lead to inaccurate predictions of tree growth and competition dynamics. Future developments could address this by incorporating a spatially explicit soil moisture model that accounts for variations in soil texture, depth, and moisture retention capacity.
Another limitation is the model's reliance on fixed parameters for physiological processes, such as photosynthesis and transpiration, which may not adequately reflect the variability observed in natural populations. To improve this aspect, future iterations of the model could incorporate a range of parameter values based on empirical data from diverse forest ecosystems. This would allow for a more flexible and realistic representation of tree responses to environmental conditions.
Additionally, the current model does not account for disturbances such as pests, diseases, and extreme weather events, which can significantly impact forest dynamics. Integrating disturbance regimes into the model would enhance its realism and applicability for forest management and conservation strategies. This could involve simulating the effects of disturbances on species composition, growth rates, and competitive interactions.