A similarity criterion for forest growth curves

Comparison of forest growth curves has led many to the conclusion that there is a similarity between forest stands growing in different conditions. Here we treat the same subject from the viewpoint of similarity theory. Our goal is to form a dimensionless ratio of biophysical entities that could parameterize the diversity of forest growth curves. (Such ratios are called similarity criteria.) Pursuing this goal, we focus on the analogy between tree crown growth and atomic explosion. A blast wave is formed when the rate of energy release is much higher than the rate of energy dissipation. The difference between the rates of energy release and dissipation is the essence of this phenomenon. The essential feature of crown growth is the difference between the rates of non-structural carbohydrate supply and demand. Since the rate of supply is much higher than the rate of demand, the flow of non-structural carbohydrates achieves the tips of branches and enables the radial growth of crown. Proceeding from these ideas, we derived the similarity criterion which supposedly captures the “essence of growth” that emerges from the geometric similarity of tree crowns.