The values of the state variables assessed during an inventory change as a result of natural growth, but even more so as a result of thinnings. The information collected may become obsolete already after the first thinning following the inventory. A different timing strategy is applied in an approach known as thinning inventory. A thinning inventory captures stand data immediately after marking the trees, but before the marked trees are removed. Thus information about thinning effects is captured, permitting not only effective monitoring of silvicultural operations but also the modelling of thinning effects and thinning behaviour of individual foresters.
Effective monitoring is a prerequisite for increasing biodiversity.
Due to its density of population landscape has preponderantly lost its virgin character. Protection and management are therefore focussed on cultural biotopes, e.g. pastures and other greenlands. Utilization, management and protection strategies might be closer adjusted to the objectives and principles of the convention on biodiversity. In practice diversity of species and habitats can often be assessed visually. Much more uncertainty is connected with the assessment of genetic diversity.