ESS221 chapter7 Ecosystem models
Channel: Richard Knight
Date: 2020-05-17

Welcome to the 7th chapter in the Conservation for climate change course. This chapter discusses the process of ecosystem function modelling, and the course material is prepared by Bob Scholes of the CSIR.


Biodiversity can be thought of as having three aspects (composition, structure and function) and three levels (the gene, the population and the ecosystem). Almost all systematic conservation planning tools focus at the species composition level (where the red dot is in this diagram). Some deal with biome or habitat modelling (red ellipse). The subject of this presentation is ecosystem function modelling (orange ellipse), which also deal to a degree with ecosystem structure. Clearly, there are gaps that current modelling processes do not cover, but when the three different approaches are combined, they do give a moderately clear picture of how it all works.


An example of an ecosystem function model used in relation to climate change are the ‘dynamic global vegetation models (DGVMs) that link to the Global Circulation Models (GCMs) and provide a changing land surface to them. These models simulate the carbon uptake and loss of the surface features, the albedo, the bulk stomatal conductivity, and the roughness of the surface as it interacts with the atmosphere. Of course, since it is dealing with a GCM (which typically have very broad scales) the best that these models have is a very crude representation of several biomes, or functional types. However, some of the better models, such as the LPJ model or the Sheffield DVGM) also include such processes as fire, and the interactions of mammals.