Ecosystem function, ecosystem processes, ecosystem services, final ecosystem services, ecosystem goods, natural capital and biodiversity – all these terms are currently very popular in ecological and related circles, reflecting the improved links between science and policy. These are important, as society considers its options for increased food production, the threats of climate change and the needs of species, habitat and landscape conservation. A recent paper by Mace, Norris and Fitter (TREE, January 2012; http://www.sciencedirect.com/science/article/pii/S0169534711002424, for those with academic access) gives a comprehensive review of the relationships between biodiversity and ecosystem services. Reading this paper and a series of in-depth research proposals on the subject over recent weeks confirms my suspicions that the area is complex and conceptually messy. As scientists, we need to have our concepts sorted, preferably elegantly, before we can make headway in presenting evidence to influence policy.
Of course one problem is the semantic one. The term “biodiversity” moved into societal use years ago and the same is now true for “ecosystem services”. As with language and species, evolution occurs and our scientific understanding of the terms is moulded by use in our human world. For “biodiversity”, Mace et al. suggest we use the definition of the Convention on Biological Diversity, which boils down to the variability of all living things. This isn’t very practical or useful, while society’s understanding is much broader, sometimes including more spiritual aspects. Turning to “ecosystem services”, we seem to be in a similar muddle. The interesting aspect of this term is that the human perspective is the key. The services and goods are for humans. It is a service if it ultimately does something for us. The corollary must be that it is not a service if there is nothing in it for us. However, processes that support function of ecosystems may provide unknown services or be unconnected to human good. In western European landscapes, where at least 70% of land is managed and all of it has some aesthetic value, perhaps every ecological process is associated with ecosystem services. Again, the term is not very practical or useful. It may have allowed the popularisation of ecology, but it isn’t helping the science and this will ultimately cause trouble in the public arena, with mixed understanding of terms.Can we please return to process, function and sustainability and drop biodiversity and ecosystem services? Mace et al. make an excellent plea that we concentrate on developing ecosystem management with a range of stakeholders. Most of ecology is context dependent, so let us embrace the many objectives of land management and concentrate on understanding the processes, with the aim of highlighting how to sustain particular systems, be they productive, semi-natural or natural.