Patterns in individual growth, branch population dynamics, and growth and mortality of first-order branches of Betula platyphylla in northern Japan

Abstract

Growth of individual trees, population dynamics of first-order branches within individuals, and growth and mortality of first-order branches were followed for two years in an plantation of Betula platyphylla in central Hokkaido, northern Japan. The data were analyzed by stepwise regressions. The relative growth rate in terms of above-ground biomass of individuals was negatively correlated with a log-transformed competition index (In(CI)), which was calculated for each individual from the size and distance of its neighbours. The change in branch number within an individual was also correlated with ln(CI). The growth and mortality of branches was correlated with the size of branches, size of individuals, growth of individuals, relative height of branches, and In(CI). Generally, the patterns revealed by the regressions were consistent with what was expected and can be used as references against which the behavior of more detailed process-based models can be checked.