g., wood quality versus total yield, spatially more explicit models, and growth decline in old-growth forests. These new problems emphasize the hierarchy of the system and inter-scale interactions. These can be constructively dealt with using a hierarchical-modular approach.
The core of the stand growth models developed by the group are models of individual tree growth throughout the rotation. At this scale, model performance requires (i) realistic long-term dynamic properties, (ii) realistic responses of growth and mortality of competing individuals, and (iii) realistic responses to eco-physiological inputs. The models developed by the group are based on carbon acquisition and allocation, combined with ideas of mutual competition through tree-to-tree interactions. In this approach, finer scale effects are embedded in parameters calculated using more detailed, interacting modules. These include, e.g., (i) the within-year effects of weather on metabolic processes, such as photosynthesis and transpiration (ii) the effects of fast soil processes on nutrient availability, carbon allocation and photosynthesis, and (iii) the utilization of detailed stem structure to predict wood quality.
References
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