Landscape change: Plan or chaos?

Landscape is a dynamic phenomenon that almost continuously changes. The overall change of a landscape is the result of complex and interacting natural and spontaneous processes and planned actions by man. However, numerous activities by a large number of individuals are not concerted and contribute to the autonomous evolution of the landscape in a similar way as natural processes do. Consequently, landscape changes in a somewhat chaotic way and man tries to control this evolution regularly by planned actions, which however, are seldom realised as they were intended. Landscapes are formed by many components which all have their own dynamics of change. Therefore, studying change must consider the nature of the component or feature looked to, as well as its specific frequency, pace and magnitude of change. To detect changes, the method to describe or measure the landscape features is important as well as the availability of adequate and comparable information in map-like format for different time periods. However, studying the change of landscape components separately seldom gives a good idea about the overall change of the landscape. The landscape as a whole looks more stable and much small change do not necessarily change its holistic appearance, its type or identity. Landscape holism is closely related to structural aspects, which reflect order and chaos. The main force behind change is the reorganisation of the existing structures to optimise their functioning. Existing landscape structures form the framework and constraint of all processes and activities in this geographical space. New needs for functioning will demand new adapted structures and will induce change. Structural order and disorder is also linked with entropy and information theory offers possibilities to describe the holistic aspects of a landscape and to measure and monitor the overall change of a landscape. A method is proposed to determine the distribution of the entropy in the landscape based upon transect sampling of landscape features on old and recent topographical maps, aerial photographs and by field survey in order to create time series. The results show that different landscape types are characterised by different entropy distributions and that changes in time can be monitored indicating different complex processes of overall landscape change. (C) 1998 Elsevier Science B.V. All rights reserved.