New Way To Model Forest Stand Dynamics
Research models are used to test current theory and advance new ways of formulating forest stand dynamics. Room for improvement exists in our understanding of how the environmentally adaptive traits of trees affect stand growth and, consequently, how we model change through time. To address this gap in knowledge, a Forest Service scientist and a collaborator have created a stand dynamics model that is the first of its kind.
Applied models of forest stand dynamics are used routinely to forecast how key forest traits will change through time. Research models, on the other hand, are used to test current theory and advance new ways of formulating models. Fundamentally, a forest is a life system, and a model of forest dynamics is a mathematical formulation of our assumptions and understanding about how that system functions.
The Forest Service scientist and Finnish partner investigated whether this knowledge gap can be circumvented with assumptions based on natural selection. They formulated a dynamic model based on the assumption that, through plasticity in structure and function, trees optimize their acquisition and use of carbon and nitrogen to maximize fitness. They selected height as a proxy of fitness, since the tallest trees in a stand are most likely to survive competitive pressures and produce offspring.
The resultant model predicts the optimal pattern by which carbon and nitrogen are coallocated, year-by-year, to the production of new fine roots, leaves, and sapwood. This stand dynamics model is the first of its kind, but predicted leaf and fine-root stocks agree with data from coniferous stands, and the optimal carbon-allocation patterns agree with published observations.
|Northern white-cedar regeneration dynamics on the Penobscot Experimental Forest in Maine: 40-year results||(publication)|
Forest Service Partners