Complexity and Simplicity in Ecosystems: The case of forest management

There are numerous examples of systems, natural as well as technical, which are considered as rather complex from a scientific viewpoint, but are amenable to successful management and control nevertheless. The approaches towards these systems of scientists on one hand and practitioners on the other are vastly different. Taking ecosystems as typical example, scientists usually rely on observations of the current status of the system, while management traditions are based on augmented memory derived from past interference and utilisation patterns. The usual attitude of scienti sts, to analyze the system and then transfer the gained knowledge to system “users” to explain its behavior to them, has not worked out for this example. We therefore try to reverse the direction of the information flow between scientists and ecosystem practitioners for Mid-European forestry as a case study for which long-term experiences as well as high-resolution data are available. To this end, we use a sophisticated tree growth simulator based on current information technologies and demonstrate two complementary views on the system: the data view may be used by scientists to validate the model against empirical observations; the management view allows foresters to interactively perform thinning and harvesting operations according to their experiences through a 3-D graphical interface (here used as an input device to the model) and visualize them. The presented framework allows an assessment of the relative appropriateness of the two perspectives. It also offers a twofold validation scheme for the model: its calibration against measurements on one hand and its evaluation in practical forestry on the other.