The way things were …

Writing the previous post led me to contemplate how much things had changed over the time that I have been working in this field.  Back in the early 1990s when I first set out to look at the response of diatoms to nutrients in streams, few in the National Rivers Authority (NRA, predecessor to the Environment Agency) regarded phosphorus as a serious pollutant in rivers, and most biologists thought about ecological quality solely in terms of organic pollution and invertebrates.   In order to investigate the effect of nutrients, I wanted to visit sites where organic pollution was not a problem.

I was helped in this task by the work done by biologists at the then Institute for Freshwater Ecology (now Centre for Ecology and Hydrology) who had just developed the early versions of RIVPACS (“River Invertebrate Prediction and Classification System”) which established the principle of expressing ecological quality as the observed quality / expected quality.  This, in turn, required an ability to predict the “expected” condition for any stream.   The work that had developed these equations started from a dataset of invertebrate and environmental data collected from a wide range of “unpolluted” running water sites which, in those far off days, was compiled by asking biologists working for the Regional Water Authorities (predecessors to the NRA) for their recommendations of sites that were of “good” or “fairly good” quality.  Nowadays, screening sites to be used for calibrating ecological methods is a much more rigorous procedure but this was the first tentative step on a long journey and “expert judgement” was as good a place to start as any.

The paper that emerged from this exercise (see reference below) analysed data from these “unpolluted” sites and classified them into eight groups.  Each of these groups consisted of sites that shared similar invertebrate assemblages which reflected similarities in the habitat, from upland, fast flowing becks to deep, wide slow-flowing rivers in the lowlands.  The authors included a useful table that listed the physical and chemical characteristics of each of these groups and I noticed that the phosphorus concentrations reported for these spanned a very wide range.   This meant that I could use these as the basis for putting together a sampling program that spanned a long gradient of nutrient pressure without the complications of organic pollution.   The outcome of that work was the first of the two papers referenced in my previous post.

Time has moved on and I thought it would be interesting to revisit these “unpolluted” sites to see how they would be classified using the UK’s current standards for phosphorus.  This highlights a striking difference between the prevailing idea of “unpolluted” in the early 1980s and the present day, as all of these groups had average concentrations that equate to substantial enrichment by modern standards; in half the groups this average concentration would be classified as “poor status” whilst the maximum concentrations in three groups equates to “bad status”.   Whatever way you look at it now, these sites were far from “unpolluted”.

Classification of TWINSPAN end-groups of unpolluted river sites in Great Britain based on Armitage et al. (1984) along with average and maximum phosphorus concentrations recorded in each group and the phosphorus status based on current environmental standards.  M = moderate status; P = poor status; B = bad status.

I am not being critical of the approach taken by Patrick Armitage and colleagues.  In many ways, I regard the work of this group as one of the most significant contributions to the science of ecological assessment in my lifetime.   I am just intrigued to see how the thinking of ecologists and regulators has moved on in the thirty years or so since this paper was published.  I know from my own early conversations with NRA biologists that inorganic nutrients were not perceived as a problem in rivers until the early 1990s.   It was probably the European Community’s Urban Wastewater Treatment Directive (UWWTD) that started to draw the attention of biologists in the UK to these problems, and which led to the development of stricter environmental standards for nutrients, though not without opposition from several quarters.

This, then is a situation where good legislation provided the impetus needed to start the process.  There were places in the UK – rivers in the Norfolk Broads, for example – where nutrients were already being regulated, but these were special circumstances and nutrient problems in most rivers were largely ignored. Indeed, as I said in my previous post, phosphorus was not even measured routinely in many rivers.   I heard via my professional grapevine that it was the Netherlands who had made the case for the clauses in the UWWTD concerning regulating nutrients, as their stretches of the lower Rhine were subject to numerous problems caused by unregulated inputs of nutrients from countries upstream.   I do not know if this is true, but it is certainly plausible.   However, once the need to control eutrophication in rivers was codified in UK law, then the debate about how to evaluate it started, one of the outcomes of which was more funding for me to develop the Trophic Diatom Index (referenced in the previous post).  And, gradually, over time, concentrations in rivers really did start to fall (see “The state of things, part 2”).   I’d like to think the TDI played a small part in this; though this might also mean that I am partially responsible for the steep increase in water charges that everyone endured in order to pay for better water quality …


Armitage, P.D., Moss, D., Wright, J.F. & Furse, M.T. (1984).  The performance of a new biological water quality score system based on macroinvertebrates over a wide range of unpolluted running-water sites.  Water Research 17: 333-347.

An open letter to Andrea Leadsom

You said something in your speech to the Conservative Party conference earlier this week that intrigued me, and I wondered if you would mind explaining exactly what you meant?  Of course, I may be reading too much into your words, which I only heard your talk because I was up stupidly early, and listened to Farming Today over breakfast.

My ears pricked up when I heard you say: “I’m truly excited that our departure from the EU means we can develop policies that are tailored to our most precious habitats and wildlife not a one-size-fits-approach for 28 Member States.”   Those are fine words but, I’m afraid I need to push you for some details.   I’ve done a lot of work on the implementation of EU environment policies over the past quarter of a century and I’m not absolutely sure where your idea that EU environment policy adopts a “one-size-fits-all approach” comes from.   The Water Framework Directive, for example, sets out general principles to ensure sustainable water supplies for Europe in the main text, but the extensive annexes give considerable scope for each Member State to tailor these principles to their own circumstances.   Even to drop the phrase “one-size-fits-all” into your talk suggests to me that you have not mastered your brief and that fills me – and other environmental professionals – with a sense of foreboding about the future of the UK environment.

However, you have not been doing the job for very long so we should give you the benefit of the doubt.   Your talk was strong on fine-sounding words but rather short on specifics.  So an easy solution to the problem may be for you to give us just one example from each of the Habitats and Water Framework Directives explaining the type of changes that your department will be looking to enact to strengthen environmental protection over and above the provisions of existing legislation.   Of course, I note that you said “… we can develop policies…” rather than “… we are developing policies …” but I am sure that you would not have said this if there were not civil servants within DEFRA currently considering just this type of option.   It is hardly an issue that is going to affect Brexit negotiations so you don’t need to resort to Theresa May’s argument of the need for discretion, and it will surely enhance your credibility among those voters who are genuinely concerned about wildlife and the environment.

One problem that I have is that you, and fellow Brexiteers, put a lot of emphasis on the red tape that Brussels generates.    Environmental and wildlife legislation often needs a “carrot” and a “stick” and that “stick” can very easily be interpreted by those on the receiving end as “red tape”.   A legitimate reading of your suggestion is that farmers and water companies may be subject to more, not less, regulation as a result of our exit from the EU.   That is counter-intuitive, given all that you, Farage, Gove and others claimed during the referendum campaign and is going to take some explaining, if it really is the case.  Once again, a couple of examples of what these new policies will look like will reassure us all.

And this brings me onto my final point: enactment of both EU policy and of your vision will only work if there are properly resourced regulators and, in my experience, the Environment Agency and Natural England have been struggling over the last few years.  Better environmental management will, of course, need more high calibre and well-resourced staff in both agencies.    Please don’t roll out that tired old mantra of greater efficiency: there is only a finite number of times this can be used before it loses credibility and, I am afraid, your predecessors have squeezed this particular argument dry.

Credibility is, unfortunately, the key word here.   Environmental professionals were very strongly in favour of “remain”, recognising the high quality of the legislation that comes out of Brussels in this field.   You came into this job without any strong track record in environment or agriculture and, I suggest, maybe you need to temper your enthusiasm for changing the status quo at least until you have mastered your brief.   An assurance that current EU legislation will not be revoked or watered down would be a good first step.   Despite claims by some of your colleagues that there was a decisive vote in favour of leaving, 48 per cent of voters want to remain.   That’s a lot of people who will be looking hard at your government’s performance come the next General Election.   Remember, too, that wildlife and conservation charities can run very effective campaigns when they think politicians are making a hash of things and that you only have a slim majority at the moment.   In other words, get this wrong and things can only end badly for you …

Who will watch the watchmen now?


There can only be one topic to write about today.   On Thursday, the UK voted, by a narrow margin, to leave the European Union and entered a period of uncertainty and instability as the nature of the “divorce” is agreed between London and Brussels.   I know that most of my UK readers were in favour of staying in the EU but at least one was in favour of exit.  And, as I know from personal experience that the EU is a far-from-perfect organisation, I am happy to accept that there is scope for intelligent people to hold different opinions on the benefits of membership.   I also accept that being anti-EU does not necessarily equate with being anti-Europe, or a “Little Englander”.  I do believe, however, that the “out” campaigns presented a distorted view of EU policy particularly on immigration, in order to play on the fears of sections of the populace.

However, what is done is done and now attention must focus on the nature of the future agreement between the UK and the EU.   As the dust settles and the bluster dies down, we awoke to a horrible truth: the “out” campaign actually have no more idea of what the future will look like than anyone else.   We now enter a period of negotiation with 27 countries, several of whom are both annoyed and worried by the UK decision, and they are not going to roll over quietly and let UK politicians dictate terms.

I have grave concerns for the UK environment after an EU exit.   The campaigns from both sides involved stripping down highly complicated arguments to a few key points that would have traction with the electorate, and then rebutting the other side’s efforts at the same. It was, in short, a campaign decided more by political process than by principle.   Unfortunately, this is exactly how environmental policy is decided at the highest level.   The sad truth is that most people’s awareness of environmental problems comes from the media, not direct experience.   Press stories can synergise with a general sense that summers are different now to when we were young to reinforce fears of global warming.  At the same time, the patterns are not so robust that naysayers cannot spin their own interpretations.   The same applies to the aquatic environment: we have (thankfully) passed the stage when many rivers looked (and smelt) appalling.  The reason we know that our rivers are polluted now is more due to media accounts, and the reason we know that they are improving is due to the Environment Agency’s press releases.  Beyond a dedicated band of anglers, few of us have enough direct experience to challenge either set of statements.

That’s where the EU played a role.   They provided a level of scrutiny above that provided by domestic politics.   I spent much of the past 15 years working towards definitions of the health of the aquatic environment that were applicable throughout Europe.   That provides a benchmark against which claims of rivers improving or declining in quality can be judged.   Bearing in mind that Europe extends from the Arctic Circle to the Mediterranean and from the Alps to areas that are below sea level, this was not an easy task, and what we have is a “work in progress” rather than a definitive product.  But it is a positive step that, to push a metaphor, “detoxifies” debates about the state of the environment.

Unfortunately, interventions such as this represent exactly the sort of loss of “sovereignty” that Ian Duncan-Smith, Nigel Farage, Boris Johnson and others decry.   So let’s unpick just what “sovereignty” might mean in this instance: it would mean DEFRA deciding on criteria to define the health of the aquatic environment, irrespective of the views of experts elsewhere in Europe.   Bear in mind that DEFRA also has responsibility for agriculture (high political sensitivities), my comments above about the susceptibility of environmental policy to “spin” and the general advocacy for “small government” from the right, and this cannot be good news for the environment.  I predict that the clause in the Water Framework Directive that allows “less stringent objectives” under certain circumstances (article 4, paragraph 5) will be applied very broadly in the UK, once scrutiny from Brussels is loosened.

What to do?   We may have to wait and see how the “Brexit” negotiations unfold.  My hope is that free access to European markets will require the UK to stay signed-up to legislation that ensures a “level playing field” for business, and that the environment will be part of this package.  This would be similar to the deal that Norway has at present, and Norwegian colleagues continue to make substantial and valuable contributions to debates on how EU environment policy is implemented.  That would mean “business as usual” for the UK environment.

However, changes in the Tory party may bring a more obstreperous breed of politician to the negotiating table and we cannot rule out the possibility that rattles will be thrown out of the pram.   Plan B, therefore, may be for independent, non-Governmental bodies such as the river trusts to steps in to scrutinise UK environment policy and measure claims against evidence.   As the Environment Agency will be even more liable to funding cuts once obligations to the EU no longer exist, such bodies will also need to watch that sufficient evidence is being collected, and maybe to collect some evidence themselves.  All that will take money, and I don’t know where that will come from.   But we need to start preparing for a world in which the “watchmen” return to being political pawns answerable only to Westminster and Whitehall.

Cadaques_2012Memories of happier times in Europe: Cadaqués in north-eastern Spain, June 2012.  The top picture shows vineyards near Bäd Dürkheim, Rhineland-Pfalz, Germany (circa. 2000), the area where my love affair with continental Europe started in 1972.  

Reflections from a Romanian lake


If you have followed my blog for some time you will know that two of my professional interests are ensuring consistency in the implementation of environmental legislation across the European Union and trying to make ecological assessment as straightforward and understandable as possible. These two interests sometimes collide briefly, particularly when I am travelling, as I have an urge to grab a sample from lakes and rivers that I pass and to make a quick judgement on their quality (see “Lago di Maggiore under the microscope” and “Subsidiarity in action”).   This isn’t quite as straightforward as it seems, as my specialism requires use of a microscope, and travelling light precludes carrying my field microscope on my travels.   Instead, I bring small, discrete samples home and have a look at the diatoms in their live state.  Enough are usually recognisable to allow me to make a rough calculation of the indices that we use to evaluate ecological status.

My visit to Romania included a trip to Lacul Cāldāruşani, on the flat lands of the Wallachian Plain about 40 kilometres north of Bucharest. It is a shallow lake, fringed by reeds (Phragmites australis) and it was from these that we collected our sample.  The reed stems were all smothered with the green alga Cladophora glomerata which, in turn, hosted a rich diatom flora.   Many of these could be either identified, or a plausible guess at their identity made, from the live state, so I was able to make a list of diatoms and, from this, to calculate the indices that we use in the UK to assess the quality of lakes.   My conclusion was that that this was definitely an enriched lake, some way below the standards set by the Water Framework Directive, which agreed with the evidence that my Romanian hosts already had.   That I can travel from near the western edge of the European Union to the eastern edge and still make a robust inference of the quality of the lake says much for the robustness of the methods with which we are dealing.

The most abundant diatom in the sample was Cocconeis pediculus, which lives on the surface of the Cladophora filaments.  This means that it is, in this case at least, an epiphyte on an epiphyte, as the Cladophora was, itself, growing on the reed stems.  Rhoicosphenia abbreviata is another diatom that lives epiphytically on Cladophora, and this was also common in the sample.  As well as these, there were at least three species of Encyonema, mostly free-living but a few in tubes, plus Navicula tripunctata and at least one other species and a few cells of Epithemia sorex.   There was also a rich assortment of green algae, but I had only limited time to dedicate to this sample, so these will have to wait for another day.


Cladophora-smothered sections of submerged stems of Phragmites australis collected from Lacul Cāldāruşani, Romania, June 2016; b. and c. Cocconeis pediculus growing on living and dead filaments of Cladophora glomerata from Lac Cāldāruşani. Scale bar: 10 micrometres (= 1/100th of a millimetre).


Diatoms from Lac Cāldāruşani, Romania, June 2016: a. two cells of Rhoicosphenia abbreviata on a stalk; b. Navicula sp.; c. Navicula tripunctata; d. Epithemia sorex; e. Encyonema sp (E. silesiacum?) growing in mucilaginous tubes.  Scale bar: 10 micrometres (= 1/100th of a millimetre).

One difference between this lake and most lakes in the UK is that the Romanians have a taste for a far broader range of freshwater fish than we do.  We enjoy salmon and trout, but there is not much enthusiasm for eating other freshwater fish here, in contrast to many parts of central and eastern Europe where fish such as carp are both farmed and eaten (we, in the UK, seem to have lost that taste, as many ruined monasteries have “carp ponds”).   Lac Cāldāruşani has a commercial fishery, and this probably contributes to the poor quality of the water.   Many shallow lakes and ponds are stocked with carp in the UK too, but for angling, not commercial fisheries.   Many of these are too small to feature on the regular monitoring programs (which only covers water bodies that are at least 50 Ha in size).   Carp, however, are fish that like to root around in the mud for food and, in the process, stir up the sediments releasing nutrients back into the water where they can be used by algae.   The algae, in turn, die and sink to the bottom where they decay and release the nutrients back to the water, only for another carp to stir them up again.  These shallow lakes are, in effect, not just polluted by this year’s inputs of nutrients, but also by pollution from the preceding decade, which is constantly being recycled as the fish search for food.

From here, we climbed back into the car to visit one other lake.  The story of that lake, however, will have to wait for a future post.


More details about the methods for assessing lake ecological status using diatoms in the following two papers:

Bennion, H., Kelly, M.G., Juggins, S., Yallop, M.L., Burgess, A., Jamieson, J. & Krokowski, J. (2014).  Assessment of ecological status in UK lakes using benthic diatoms.  Freshwater Science 33: 639-654.

Kelly, M., Urbanic, G., Acs, E. Bennion, H., Bertrin, V., Burgess, A., Denys, L.,  Gottschalk, S., Kahlert, M., Karjalainen, S.-M., Kennedy, B., Kosi, G., Marchetto, A., Morin, S., Picinska-Fałtynowicz, J., Poikane, S., Rosebery, J. Schoenfelder, I., Schoenfelder, J., Varbiro, G.(2014). Comparing aspirations: intercalibration of ecological status concepts across European lakes for littoral diatoms.   Hydrobiologia 734: 125-141.

Evolve or die?


Last June, I wrote a post titled “So what?”, which included a cartoon summarising all that I thought was wrong with the world of diatom specialists within which I move.   We have become, as a group, very good at naming and counting diatoms, but not very good at understanding how these fit into ecosystems.   Along with two colleagues, I included this cartoon in a paper that we wrote based on talks at the meeting that I wrote about in that post. One reviewer took umbrage at this, suggesting that “… it is really making a very bad favour to all the people working with diatoms, and to the efforts expended during many years to implement techniques related to them …” (sic).   Unfortunately, I feel that there is so much complacency amongst diatom specialists at present that we are hardly doing them a favour by writing platitudes. Inhabitants of the curious sub-discipline of diatom science seem to have drifted far from the frontline of functional ecology and some shock tactics are necessary in order to drag them back towards reality. We argued our case for including the cartoon and the editor agreed with us.

The roots of the problem are sociological and cultural rather than scientific: diatoms became established as the first choice algae for ecological assessment for a number of reasons, one of which was the absence of competition from advocates of other groups of organisms. Diatom methods behaved like an invasive species, spreading rapidly across Europe and beyond, exploiting the new “niche” created by the Water Framework Directive’s requirement that “phytobenthos” (i.e. attached algae) should be considered when Member States were evaluating the condition of their fresh waters.

What happened next was, I suspect, the natural consequence of academic specialisation. We all recognised that the first generation of methods were far from perfect but, as circumstances had selected diatom specialists (with their inclinations towards taxonomy) over those with interests in other algal groups and, more significantly, ecological processes, these people then dictated the next stages of development.   Over the past 15 years, I have watched the lists of species that analysts are expected to recognise gradually grow in length in many parts of Europe. Adherents of this approach claim greater sensitivity as a result, but there is little hard evidence to support this.   Rather, I think we are watching the natural inclination of specialists towards greater specialisation.

The line that we took in our new paper is that the “ecological status” that we are all trying to measure is a much broader concept than can be encapsulated by the composition of a single group of algae.   Importantly, it needs to consider not just what species are present but also how much biomass these create.   We recognise that measuring biomass is not an easy task but, paradoxically, diatom specialists in yet another recent paper point out that differentiating some groups of diatoms is difficult yet seem to think that this can be resolvable by greater diligence on the part of analysts, whilst every other facet of ecological status can be quietly ignored.

My inclination is to aim for much greater breadth of information in our assessments, accepting, at the same time, that this may entail less detail within the individual nuggets of information (see “The democratisation of stream ecology?”). There is, I recognise, a fine line between “streamlining” a method and “cutting corners” but it may be a price worth paying in pursuit of a wider goal. I explored this in a recent paper on redundancy in lake assessments (see “Unmasking the faceless Eurocrats …”), invoking the economic principle of “decreasing marginal utility”. Broadly speaking, the information content of any individual type of data decreases by a power law, such that the first 20% of effort (roughly) yields 80% of the answer.   The unique information content associated with the extra effort gradually tails off.   The question that no-one has satisfactorily answered is whether the “splitting” that now seems axiomatic amongst diatomists adequately balances the huge amount of information (on other algae, on biomass) that is completely ignored.

It seems straightforward if put in purely scientific terms, but the situation is complicated, again, by non-scientific, socio-cultural aspects. Specialist biologists, like all craftsmen/craftswomen, take pride in doing the best possible job. It is possible, too, that the extra data that they extract from a detailed analysis may turn out to be useful in the future, so why ignore it?   On the other hand, the creation of a cadre of specialist “diatomists” means that they see the “best possible job” exclusively in terms of their data and not in terms of the overall management of a river or lake. And finally, the widespread adoption of diatoms for assessment has created a niche for specialist contractors who work for environmental agencies and others performing the highly detailed analyses that are currently required. Any attempt to “streamline” the process threatens their livelihood.   So what starts as an impartial scientific debate is anything but, as the “Guild” of diatom analysts marshals its arguments.

Our paper forms the introduction to a series of papers arising from the Trento meeting. It may seem strange to open the proceedings with a fairly negative evaluation of the state of affairs, but I offer no apologies.   Pushing my ecosystem analogies just a little further, “specialist” organisms are vulnerable to changes in their habitat in a way that “generalists” are not.   The landscape of environmental regulation is not static and biologists, no less than the organisms they study, need to evolve in order to survive.


Kahlert, M., Ács, E., Almeida, S.F.P., Blanco, S., Dressler, M., Ector, L., Karjalainen, S.M., Liess, A., Mertens, A., van der Wal, J., Vilbaste, S. & Werner, P. (2016). Quality assurance of diatom counts in Europe: towards harmonized datasets. Hydrobiologia (in press) DOI: 10.1007/s10750-016-2651-8

Kelly, M.G., Schneider, S.C. & King. L. (2015).   Customs, habits and traditions: the role of non-scientific factors in the development of ecological assessment methods.   WIRES Water 2: 159-165.

Poikane, S., Kelly, M.G. & Cantonati, M. (2016). Benthic algal assessment of ecological status in European lakes and rivers: challenges and opportunities.   Science of the Total Environment (in press). (doi: 10.1016/j.scitotenv.2016.02.027) (The picture at the head of this post is the “Graphical Abstract” from that paper which is “open access”, thanks to the European Commission’s Joint Research Centre)

Unmasking the faceless Eurocrats …


My own small contribution to the campaign to keep the UK in the European Union takes the form of a scientific paper. This will probably not raise many eyebrows outside the small band of specialists amongst whom I work but it offer it as an antidote to the rhetoric of the anti-EU campaigners and their scaremongering about the Brussels bureaucracy. I have made no secret that I am pro-EU (see “What has the European Union ever done for us?”) and that I think the UK benefits from EU environmental legislation. What one person thinks to be sensible regulation can easily be portrayed by the disingenuous as excessive red tape peddled by faceless, unelected Brussels bureaucrats.

Our paper deals with about half a sentence in an annex of an 80 page Directive that deals with how EU Member States should assess the quality of lakes.   Should the suspended algae, the attached algae and the larger plants be used to assess lake condition, or can you get the same outcome by just using two of these three components? Interpretation of those few words can, however, result in considerable and recurring expense for a large Member State such as the UK.   Opinion on how they should be interpreted differed between the 28 countries of the EU.   How do you find the balance between the environmental risks associated with lax interpretation of EU law and the extra costs that a stringent reading of the Directive would entail?

I was contracted, along with two colleagues, by the European Commission’s Joint Research Centre to look into this issue by examining the datasets of those countries that had analysed all three components to see how much extra information additional types of monitoring added to a manager’s overview of lake condition.   One additional twist to the problem was that my own particular specialism, the attached algae, was the Cinderella at this particular ecological assessment Ball, with about 60% of EU states deciding that these were not necessary.   Ironically, my career as Fairy Godmother to fellow algal specialists was extremely short-lived, as the outcome of our analyses was that, if a lake had a problem, it could usually be detected using the suspended algae and higher plants (the “ugly sisters” … metaphor overload .. no more of this, I promise).   There are situations when all three are needed to understand how to manage a lake but, for strategic overviews of the condition of a country’s lakes, little was gained by including them.

So what has all this got to do with our EU referendum?   In brief, this was a matter of interpretation discussed by representatives of all Member States at meetings mediated by European Commission representatives.   Having identified a difference of opinion, they brought us in to work on an evidence-based solution which was then discussed, in depth, at another meeting of national representatives (mostly ecologists). Many agreed with our conclusion; a few made the case for continuing to use all three components.   Ecological arguments were put forward by both sides but, in essence, we were debating whether this was an issue that should be decided within or between Member States.   Most were happy that this level of detail could be determined within Member States.   Even if the outcome had been in favour of imposing a more rigorous interpretation of the Directive, it would have been the consensus of Member States enacted through the Commission, not a blanket edict from these (hypothetical) faceless bureaucrats that the right wing press constantly demonises.

An interesting coda to this story is that after our report had been circulated and discussed my colleague at JRC was contacted by people from one Member State who were slightly alarmed by the conclusion.  The point that they made was that devolving responsibility to individual countries would lead to many dropping the use of attached algae, simply on the grounds of financial expediency. I had some sympathy (one of the authors was a fellow consultant who, like me, makes part of his living from this type of work) but it also touched on something that has been exercising my mind over recent months.   Do countries use this type of monitoring because they have to (i.e. the Directive tells them to) or because they need to (i.e. it contributes valuable information to lake management)?   It shifts the onus on us, as advocates of a sub-discipline, to make a reasoned case for the continued use of attached algae, rather than simply assume that “Brussels” will guarantee our livelihood.

Note: the photograph shows Derwent Water in the English Lake District, looking south from Friar’s Crag, July 2015.


Kelly, M.G., Birk, S., Willby, N.J., Denys, L., Drakare, S., Kahlert, M., Karjalainen, S.-M., Marchetto, A., Pitt, J.-A., Urbanič, G. & Poikane, S. (2016). Redundancy in the ecological assessment of lakes: Are phytoplankton, macrophytes and phytobenthos all necessary? Science of the Total Environment

Making what is important measurable …

I heard an interesting discussion on Radio 4 a couple of weeks ago that set me thinking about the theoretical basis of ecological assessment. The discussion, paradoxically, was about education rather than ecology, but I have mentioned in the past that there is common ground between these two disciplines (See “The madness that is “British values”).   The discussion involved a comparison of the education systems of the UK and China.   In many measures, the education system in China appeared to be outperforming that in the UK, but one contributor questioned whether the measures being compared were actually appropriate.   China appeared to perform better than the UK because the measures being used were crude assessments of the proportions of students that passed exams and which, therefore, favoured rote-learning over more interactive approaches to education. The contributor went on to suggest that this search for easily quantified measures of school performance was part of a more general problem.   The telling distinction that he used was “making what is measurable important” versus “making what is important measurable”.

That summarises my series of posts from June (see “The human ecosystem of environmental management …” and the two subsequent posts).   We have made progress over the last two or three decades towards developing criteria that are “important” rather than just “measurable”.   Go back to the early 1990s and being able to demonstrate that the composition of the diatom assemblage was significantly related to the concentration of phosphorus in the water was a step in the right direction but there was little “added value” compared to just measuring the phosphorus concentration (which was a necessary part of the regulation process).   During the 2000s we took this a step further, driven by the precepts of the Water Framework Directive (WFD). By the end of the decade we had a good idea of what diatom assemblage could be expected at any river or lake site and use that to measure how far the present state of a site deviated from this ideal. The question that bugged us throughout, though, was how much deviation was acceptable.   The problem with an ideal is that it is probably unlikely to be attainable, so we need to infuse our ideals with a spoonful or two of pragmatism (supporters of Jeremy Corbyn, please note …).   This is, in fact, at the heart of the WFD, encapsulated in the definition of “good ecological status” (GES). The problem is that GES, itself, is an elusive concept.

The outcome of this is that is has tended to be defined in terms of the “measurable” rather than the “important”. By this I mean that various statistical approaches have been used to determine a point along the index scales that we have developed that we thought met the definition of good ecological status as set out in the WFD.   This describes GES as a “slight change” from the community structure associated with the ideal state (“reference conditions”).   What has concerned me for some time is that this “slight change” does not necessarily have deep foundations in ecological theory, and does not necessarily guarantee the long-term sustainability of Europe’s waters, the ultimate goal of the WFD.   We could argue that a “slight change” leans towards precaution, but the downside is that it is hard to justify the expense of restoration when your argument is littered with “probably” and “maybe”. So where should we look in order to find these deeper foundations?

I came across an interesting new paper that points us in some new directions, if stopping short of giving detailed answers.   It focuses on the concept of ecological resilience, defined as “the amount of disturbance that an ecosystem could withstand without changing self-organized processes and structures” (see the reference by Gunderson, below).   “Ecological resilience” is no more than preserving the natural homeostasis of a system; just as a healthy human should have the resilience to recover from a minor infection, so an ecosystem should have the capability to recover naturally, without management intervention, from minor natural or anthropogenic perturbations. What this then does is set us some new challenges to understand what we mean by “resilience” in freshwater ecosystems and then to develop some ways of measuring this.   I made some suggestions in a post back in January (see “Baffled by the benthos (2)”) and there is scope for other approaches too. These, then, would let us re-examine how we set the limits for GES and, in turn, give us stronger justifications for their restoration.   Of course, all this assumes that GES is a steady state that fulfils this definition of possessing “self-organized processes and structures”, but that is the subject for another post …


My own thinking on the ecological theory behind good ecological status is described in:
Kelly, M.G., King, L. & ní Chatháin, B. (2009).   The conceptual basis of ecological status assessments using diatoms. Biology and Environment: Proceedings of the Royal Irish Academy 109B: 175-189.

The other two papers I refer to are:
Gunderson, L.H. (2000). Ecological resilience in theory and application. Annual Review of Ecology and Systematics 31: 425-439.

Spears, B.M., Ives, S.C., Angeler, D.G., Allen, C.R., Birk, S., Carvalho, L., Cavers, S., Daunt, F., Morton, R.D., Pocock, M.J.O., Rhodes, G. & Thackeray, S.J. (2015). Effective management of ecological resilience – are we there yet?   Journal of Applied Ecology DOI: 10.1111/1365-2664.12497