24: Perspectives in Ecological Modeling

MCED Chapter 24

Title

Perspectives in Ecological Modelling

Authors

Fred Jopp, Broder Breckling, Hauke Reuter, and Don DeAngelis

Ecological Modelling: A matured discipline

(from the book)

In the chapters of this textbook we have presented a broad panorama of the network of discourse from which Ecological Modelling emerged and grew. Starting from the very early days, we have proceeded to give an overview of a wide spectrum of currently available approaches. Then, after looking at a selection of prominent model applications, we discussed how to assess model validity.

In the beginning, ecological modelling was largely influenced by approaches outside of biology. Ecology was one of the disciplines that started relatively late to use quantitative methods and theory. One relevant impetus for considering quantitative relations came from economics (Malthus, 1798). Quantification of human interference with natural systems has always been relevant in agriculture. With the development of agricultural chemistry (Liebig, 1831), the targeted adaptation of quantitative methods to production-oriented ecosystems became important. The quest to understand density-dependent regulation (Verhulst 1838, Pearl 1927), predator-prey interactions, and species competition sparked the borrowing of differential equations from classical mechanics (Lotka-Volterra equations; Lotka 1925; Volterra 1926) to analyse ecological dynamics. While the differential equation approach was successfully applied to areas of population ecology, it was structurally not as adequate for addressing the heterogeneity within populations (e.g., size and spatial structure) as it was for addressing dynamic and equilibrium behaviour at the level of whole populations and simple food webs. While analysis of food webs tended to be dominated by a few standardized approaches, such as energy or biomass budget models (Chap. 5, Ecopath), a wider variety of approaches emerged to deal with heterogeneity within populations. The challenge that drove methodological development for a number of decades was how to cope with the difficulties of representing temporal and spatial heterogeneities. With the development of object-oriented approaches (Dahl et al. 1968; Kaiser 1976, 1979, Hill 1996) and its import into ecological modelling (Hogeweg & Hesper 1983, Huston and DeAngelis 1988; DeAngelis and Gross, 1992, Wolff 1994), it is reasonable to state that the broad spectrum of situations ecology deals with can now nowadays met by an adequate spectrum of approaches, which can be applied in isolation or in combination with other approaches – whatever is required by the problem under investigation.

Fig. Different views of the Zugspitze (Bavarian Alps), highest peak in Germany. The site is located in the Wetterstein Mts. range in the Northern Limestone Alps, Photo: Fred Jopp


This successful development of a highly flexible repertoire of quantitative approaches is why we consider ecological modelling to be a mature discipline. It consists of a large body of methodologies appropriate for the full spectrum of ecological research, from the assessment of small-scale and short-term individual behavioural pattern (autecology) through various scales and levels of organisation (population, ecosystems, landscapes and biomes) up to processes on the biosphere level. Because of the wide range of approaches available, both the student who is interested getting his or her bearings in this field, and the researcher already working in ecology, need some help and orientation to identify the most reasonable approaches for a given problem.