Ecological Modelling had its 25-year anniversary last year, which was celebrated at a so-called Ecosummit meeting with the participation of several Elsevier journals in the field of ecology. The first issues were published in 1975, and it was very difficult to get enough publications for the first volume, although we only published 320 pages per annuum. Today, Ecological Modelling publishes 3,600 pages per annuum, and we have enough publications for about twice as many papers. Ecological modelling is a well-recognized and widely used tool today in environmental management and ecosystem research. Forty-three countries have published in the journal; although most papers are coming from Western Europe (47%), U.S. (33%), and Japan (9%), recently, several papers from China have been submitted to the journal.

In accordance with the editorial policy, the following topics are covered by the journal: ecological modelling, application of ecosystem models in environmental management, and ecosystem theory or system ecology. All three areas are included, because our philosophy is that we cannot model a system if we do not know its properties, and the experience gained from application of models as an environmental management tool is very valuable for the more theoretical modellers. On the other hand, the very theoretical models can inspire the modellers of practical environmental problems, and models are powerful tools in the development of ecosystem theory, as it has been shown several times in the journal.

Furthermore, the editorial policy is to publish discussions of controversial papers and to be very open to new ideas and theories. Such papers may not be correct in all detail in the first instance, but by publishing them, a discussion gets started and this will almost always lead to progress in our ecosystem theories and modelling techniques. I believe that it is one of the factors which has made the citation index grow lately.

The trends in ecological modelling are towards application of a broader spectrum of modelling approaches. Some examples of these include: artificial neural networks, fuzzy modelling, and what is called structurally dynamic modelling, which is able to describe the current changes in the properties of the dominant species using a goal function. We also use more integrated models—models which integrate land use with pollution in aquatic ecosystems or landscape models or economic ecological models. Moreover, the journal has a goal to facilitate reader access to the models published in the journal. Recently, an interactive modelling course has been launched on the internet in the hope to get even more people interested in environmental problems and ecology to get involved in modelling. Overall, the journal is ready to take up the challenges that will inevitably come in the area of ecological modelling and system ecology in the coming years.

Sven Erik Jørgensen, Professor, Dr. Eng. Dr. Scient.
Editor-in-Chief, Ecological Modelling
Elsevier Science, publishers
Copenhagen, Denmark