An image with which to conjure …

I worry that my ruminations on how ecological information flows through the “human ecosystem” of scientists, regulators and policy makers contradicts some of my earlier statements about the importance of field-based biology (see, for example, “Slow science and streamcraft”).   It lies at the heart of another problem: that the need to create reproducible, comparable data across an entire country leads to biologists being reduced to “data monkeys”, optimised to operate as part of a production line that grinds inexorably from sample collection to delivery of results (see the flow chart in the preceding post). How do we ensure that organisations have access to all the knowledge and wisdom that a professional biologist accumulates, and not just to the digestible chunks of “information” that I talked about earlier?

I’m going to try to answer these questions by stepping outside of biology and into the world of organic chemistry, because I think that we need to think from the perspective of an outsider looking into our cherished world. I gave up chemistry at age 16 and was force-fed just enough subsequently to get through my degree and PhD.   However, it is not a world in which I feel comfortable. Yet the regulation of toxic chemicals is just as vital to the well-being of our freshwaters as management of biological communities. The Water Framework Directive, for example, set out some general principles on the management of chemicals which present a significant risk to or via the aquatic environment.   Guidance on these “priority substances” was developed through a series of Decisions and Directives (e.g. 2008/105/EC – see below). The list includes heavy metals such as cadmium, but also a long list of organic chemicals. Let’s take one of these at random: di(2-ethylhexyl)-phthalate, which is widely used as a plasticiser.   No, I didn’t know that either. And, yes, in light of what is to follow, I really did choose it at random.

Suppose someone tells me that the annual average concentration of di(2-ethylhexyl)-phthalate in a local river is 5 micrograms per Litre.   What do I conclude?   Not a lot, unless I also know that the Environmental Quality Standard (EQS) for this compound is 1.3 micrograms per Litre.   In fact, as a non-chemist, all I really need to know is that this river fails the EQS for di(2-ethylhexyl)-phthalate.   In other words, whilst the biologist part of me balks at the idea of reducing detailed data about the composition of the algal community down to a simplistic metric, I am quite happy when other people do this for chemicals, in order to make my life easier.   I can scan down a long list of priority substances, and quickly spot those that present a problem in any particular river.

Let’s take a closer look at what is happening: the EQS is based on a lot of toxicological data.   It is good to know that this has been done, but I don’t actually need any of the details. Nor do I need to know much about the way analytical chemists measure di(2-ethylhexyl)-phthalate.   There is probably a CEN or ISO standard detailing the procedures but for me, as a token end-user, these are details that I don’t need.   All I need to know is whether or not the di(2-ethylhexyl)-phthalate concentrations represent a problem or not and, perhaps, a qualifier (“definitely”, “probably”, “maybe”).   I can then take this desiccated nugget of information and “rehydrate” it (as it were) with appropriate context when needed.   Suffice it to say that there is toxicological evidence linking this compound to decreased penis width. Fifty percent of my readers are now forming a mental image that converts the concentration of this obscure organic compound into a genuine threat to the future of humankind. Don’t pretend that you are not.

The same kind of process should happen in ecology. We take a lot of data that represents a complex idea (the ecological health of a river), distil this into a nugget of information (an Ecological Quality Ratio), then hope that our “customers” (that word again, I’m afraid) can conjure the appropriate mental images in order to use it appropriately.   My colleague Nigel Willby addressed this in an editorial in the journal Aquatic Science and Conservation a few years ago. He pointed out that ecologists work at a level of detail that is far too esoteric for the average manager, let alone the man in the street to comprehend easily. He went on to say that “Our basic currency needs to be far more generic, transferable and indeed utilitarian if we are to argue more effectively for the resources to manage or restore degraded aquatic habitats”. Just as decreased penis width gives us a mental image that 5 mg/L of di(2-ethylhexyl)-phthalate will never supply, so we need a “guiding image” of the state of ecology. Nigel was arguing for this image for larger plants, but the same point applies, I believe, for microscopic organisms too. The idea of algae as the “back room staff” of healthy ecosystems, converting sunlight into carbon, reoxygenating water and generally acting as a “supporting ecological service” needs to pop up in a manager’s head whenever s/he sees one of the nuggets of information that our hard work and training has produced. More often than not, algae are regarded as a potential nuisance that needs to be kept at bay, rather than as an asset with both local and global benefits. And I think that there is little point in producing better methods of assessing ecological health using algae unless we can overcome this limited potential for our information to be interpreted by non-technical colleagues and stakeholders.

I’m drawing closer to Trento, and my plenary talk, spatially, temporally and mentally. One more post on this subject to come …


European Union (2008). Directive 2008/105/EC of the European Parliament and of the Council of 16 December 2008 on environmental quality standards in the field of water policy, amending and subsequently repealing Council Directives 82/176/EEC, 83/513/EEC, 84/156/EEC, 84/491/EEC, 86/280/EEC and amending Directive 2000/60/EC of the European Parliament and of the Council. Official Journal of the European Union L 348: 48-97.

Kelly, M.G. (2012). The semiotics of slime: visual representation of phytobenthos as an aid to understanding ecological status. Freshwater Reviews 5: 105-119.

Swan, S.H. (2008). Environmental phthalate exposure in relation to reproductive outcomes nad other health endpoints in humans.   Environmental Research 108 (2): 177–184.

Willby, N. (2011). From metrics to Monet: the case for an ecologically-meaningful guiding image. Aquatic Conservation: Marine and Freshwater Ecosystems 21: 601-603.