Agricultural Management

Valuing the impacts of ecosystem service interactions for policy effectiveness

Project Leader: Mr Alistair McVittie, Scottish Agricultural College

The project has now ended. Here is a summary of the findings; the full project report will be available soon.

The project brought together a team of soil scientists, ecologists, modellers and economists. The aim was to develop an understanding of how ecosystem processes and services interact to produce benefits to people, in an agricultural system.

 The project team studied this at two scales: at a catchment scale using data from Loweswater in the Lake District and also at a landscape scale.

Workshop

An initial workshop of academics and policy makers considered the interactions between ecosystem processes and final ecosystem services and how these are influenced by management and policy.

The workshop highlighted how complex these interactions are and indicated that in order to make progress a narrower scope might be required for the project.

This led to an exploration of interactions between ecosystem processes and the range of ecosystem services delivered by adopting specific management actions, namely the use of buffer strips or riverside vegetation, aimed at improving water quality.

Management action: buffer strips

• Management actions on agricultural land, such as buffer strips, can be used to protect water quality in rivers and lakes.
• Buffer strips may also help to deliver other benefits such as flood management, greenhouse gas mitigation, biodiversity, landscape and recreation.
• However, they may conflict with other management aims, notably food production, by taking land out of cultivation or grazing use.
• All the potential outcomes must be considered when considering a management action in order to get optimal benefits.

Model

• Bayesian Belief Networks (BBNs) were identified as a suitable approach for exploring ecosystem processes and service interactions.
• These have the advantage of being able to utilise different types of data and knowledge, including expert judgement.
• We have explored the development of BBNs at two distinct scales, one a small well studied catchment (Loweswater in the Lake District) where we have detailed knowledge of biophysical processes; the other at a wider, landscape scale, as way of exploring the potential for this instrument to simplify policy-making.
• As these models operate at different scales they are of use to different policy audiences; although both consider similar management actions and impacts.
   

Valuation

The modelling has highlighted issues that need to be addressed with respect to valuation, such as the lack of predictability in the ecosystem outcomes and hence their associated valuation scenarios.

While these can be reflected in the probabilistic nature of the BBN, valuation then needs to account for a range of potential baseline and policy change scenarios. This is an area which requires further development and should form a key part of future work exploring how to value nature.