Jonathan Baker is a graduate of Bath Spa University and Imperial College London and currently a consultant at Collingwood Environmental Planning where understanding what ecosystem services are and what they mean for environmental and planning policy is a fascination.
Thoughts on our evolving consideration of the relationship between biodiversity and ecosystem services and what this may mean for the management of UK’s natural environment, particularly with the increasing emphasis on enhancement.
As you may be aware the term “ecosystem services” has come to dominate much of the current discussion about the natural environment. The rise of this concept is remarkable, from a few papers in the 1990s to its current status as a central part of UK, European and international environment policy. Within this context, this article seeks to describe our understanding of the relationship between biodiversity and ecosystem services and what this may mean for the management of the UK’s natural environment.
To recap, ecosystem services are the benefits that we as individuals and as a society receive from the natural environment. Effectively ecosystem services are the product of ecological and natural processes and interactions. Examples of these services include providing us with: food (so called provisioning services); natural areas to enjoy (cultural services); flood storage (regulating services); and soil formation (supporting services).
To date much of the debate over the use of this concept has come from attempts to assign monetary value to the natural environment based on the services provided. The idea of attributing £ signs to the natural environment, which was previously considered to be worth protecting for its intrinsic worth and spiritual and ethical reasons, meant that ecosystem services has been perceived as an essentially reductionist, selfish and money driven concept. Over time these concerns have been diluted as the main argument for the use of ecosystem services, that previously the value of biodiversity was invisible in decision making, has won out and the value of ecosystem services as a useful concept when making the case for protecting or enhancing the natural environment has been realised.
The evidence of this is clear with the UK Natural Environment White Paper (NEWP) mentioning ecosystems services 58 times (in 84 pages) and the European Biodiversity Strategy 23 times (in 17 pages).
Throughout these documents biodiversity and ecosystem services are generally synonymous and there appears to be an implicit assumption that measures to protect or enhance biodiversity will lead to the increased provision of ecosystem services and vice versa. However the relationship between biodiversity and ecosystem services is more complex than that and there is the risk that not making this explicit may undermine the positive potential of the ecosystem services concept. More importantly the interpretation of this relationship has real implications for policy makers and practitioners; especially considering the recent focus on enhancing the natural environment.
The nature of the relationship
Our understanding of how biodiversity relates to ecosystem services is still in its infancy. The most established way to consider this relationship is that biodiversity is in effect a central part of the machinery which provides ecosystem services. If this machinery is damaged or removed then the services we receive decrease and at some point irreversibly stop.
There is however a huge amount of uncertainty within this description. For instance the extent to which biodiversity can be reduced and service provision remain relatively stable is unknown in almost all cases as the thresholds of service collapse are context and ecosystem specific. As such the condition and status of ecosystem services is generally unclear. This signals a core difference between the two, with ecosystem services having provable monetary value to society but it being hard to measure their condition whereas biodiversity can be measured but it is difficult to assign monetary value to specific species or habitats.
Interpretation in practice
There are other differences that can be articulated by example.
The UK’s woodlands provide a range of ecosystem goods and services in the form of timber products as well as storing significant amounts of carbon and forming the background to a large amount of recreational and cultural activity; they are also one of the UK’s most bio-diverse terrestrial habitats. A major challenge is managing the UK’s woodlands to balance these various and often competing aspects of woodland use. To put it simply “more trees do not equal more wildlife” and more wildlife does not equal more timber products or, necessarily, more carbon storage.
This conflict between service provision and biodiversity has led to significant revision in a major global forest protection programme – the United Nations’ (UN) Reducing Emissions for Deforestation and forest Degradation (REDD). The REDD programme provides payments to forest owners and managers to maintain trees to act as a carbon store, initially this system did not recognise the need to manage biodiversity separately to carbon storage. The assumption was that keeping trees standing would protect biodiversity. Subsequently it was feared that many REDD projects may focus on carbon storage alone and not effectively consider or protect biodiversity. The UN has since launched REDD+, with the + indicating a more holistic view of forest management which explicitly indicates the need to distinguish between payments for ecosystems services (PES) and biodiversity management.
Woodland management is an area where there may be direct conflict between optimizing service provision and increasing biodiversity and as such provides a cautionary tale that biodiversity and ecosystem services are not one and the same.
Cultural ecosystem services are generally harder to quantify and value than other services, due in part to their less tangible nature. For example, what is the value of a dew laden spider’s web or a walk in a park? Valuation is considered to be possible by assessing personal decisions and opinions regarding the natural environment. One of the clearest aspects of valuing cultural services is that experiencing the environment is core to valuing it.
There is, of course, significant value in knowing that somewhere there is a wooded area which echoes with the rat a tat of a green woodpecker but this “existence value” is quickly exceeded by actually experiencing these areas. There are however established conflicts between maximising these sorts of cultural services, for instance by increasing visitor numbers, and delivering biodiversity objectives. Conservation activities may for instance require management that limits human activity. Examples of such management may include using grazing animals on grass or heath lands or the use of fire, both of which may be considered detrimental to recreational use. These are challenges that reserve managers and wardens are used to addressing and their inclusion here is to provide further evidence that managing biodiversity and ecosystem services requires different goals and potentially different approaches.
One of the unique aspects of managing or enhancing ecosystem services, as opposed to biodiversity, is the need for additional capital inputs. For example the “value” of a fish in the sea or the view from Snowdon is not realised without the introduction of a hook and line or some form of transport respectively. Effectively many ecosystem services do not ‘exist’ or exist to a lesser extent without humans and often without capital input. Therefore unlike biodiversity ecosystem services often require additional infrastructure, which may itself impact on biodiversity.
So what is the response?
What does it mean for policy makers and practitioners if we are to understand that biodiversity and ecosystem services are different and that their related management and enhancement activities are also potentially different?
Initially it requires us to understand that both biodiversity and to some extent ecosystem services are spatially specific and cannot be replicated as and when they are required. As such there is a need to consider and allow for local context and priorities –in some instances this will mean that the focus is on a specific element of biodiversity such as a target species or habitat and in other instance this will require the prioritisation of a specific ecosystem services such a flood regulation or water quality.
This is not a binary choice, in many circumstances management and enhancement activities will deliver both improved biodiversity and ecosystem services but it is not enough to assume this. Rather as part of the management of an area or the consideration of a policy it is vital to consider ecosystem services and biodiversity as separate (but related) aspects of our natural environment. This will need to be informed by an understanding of the local priorities within the national context as well as the potential of the area under consideration. For instance is there a local need to improve flood storage, increase recreation or protect a particular species.
Realising potential ecosystem services and maximising the trade offs are something that was suggested as a result of the UK National Ecosystem Assessment (UKNEA). Lead author Ian Bateman suggested that there would be a significant increase in ecosystem services if low quality grassland currently used for low intensity agriculture was enhanced through afforestation. In particular he suggested that areas that were nearest to urban areas should be prioritised for afforestation as this is where cultural services can be enhanced most efficiently.
This is not necessarily a good idea, but it does signal a potential benefit of considering ecosystem services and biodiversity separately. The ability to pull apart individual services and consider the priorities and potential tradeoffs, perhaps based on societal preferences or defined trade off rules.
The prioritisation of ecosystem services is not new. This is essentially what we do with suitable land where provisioning services (food production via agriculture) are prioritised over others. It is also true that different ecosystem services are provided by different aspects of biodiversity, so as much as we have prioritised biodiversity to date we are have also prioritised ecosystem services. We might as well make this explicit and consider the tradeoffs.
Arguing that the environment is an asset that should be “optimised” – is not particularly appealing but what it lacks in poetry it makes up for in power and arguably represents the logical evolution of our thinking about ecosystem services.
In many instances there will be a need to focus on biodiversity for its own sake. Certain key species and habitat types are in urgent need of support and management and enhancement activities can improve individual site quality as well as the coherence of the natural environment more generally. As we have discussed, in some instances there will be a need to prioritise biodiversity at the expense of other services. In other instances delivering multifunctional landscapes might be the appropriate approach.
When considering the relationship between biodiversity and ecosystem services it is worth recalling that the primary driver of natural environment policy has been to deliver biological outcomes. As such there is potentially an argument that we should have a hierarchical relationship with biodiversity taking priority over ecosystem services? This article seeks to express that this prioritisation should be explicit, considered and transparent.
By tending to conflate biodiversity and ecosystem services current policy has potentially missed an opportunity, but the flexibility of the current policy framework does allows for local decision makers to separate and prioritise biodiversity and ecosystem services based on their local context. By considering biodiversity and ecosystem services as separate aspects of the same complex system we have the potential to create a more honest and effective discussion about how we are managing and enhancing the natural environment.