Distinguishing between change and growth in forest surveys

Much of the research in forest inventory has focussed on the generation of estimates of forest attributes at particular times and estimating how these attributes change over time. In descriptions of this work in recent decades, the terms forest growth and forest change have been used interchangeably. In this paper, the distinction between growth and change is defined and an example is given illustrating the differences between the two. Unbiased estimators of both processes are presented, and a simulation study with an artificial population is used to illustrate their properties. The results of the simulation study indicate that estimates of forest growth tend to be slightly more efficient than estimates of forest change.