Managing Conflicting Objectives in Agricultural Production and Water Resource Protection

In Swiss agriculture, conflicts arise between production and the protection of water resources. These were studied by means of multi-criteria decision analysis (MCDA): objectives are defined, evaluation functions proposed and measures analysed.

Under the Federal Constitution, Swiss agriculture is required to be multifunctional. This means that, as well as producing food, it must ensure the best possible protection of natural resources. This can give rise to conflicting objectives, e.g. regarding production and water resource protection. Often, the various objectives – and particularly the relative weights attached to them – are not explicitly formulated, or attention is restricted to certain aspects. If only a limited area within the whole system is considered, other negative (or even positive) impacts of measures may not be analysed. Collateral effects are thus ignored, and decisions are less soundly based. Conflicting objectives and the complexity of the agroenvironmental system make it difficult for policymakers and practitioners to find the optimal solution in each case.

Water-friendly agricultural production

Against this background, from 2013 to 2015, the project “AProWa – sustainable water-friendly agricultural production in Switzerland” was jointly carried out by Eawag, the FOAG and Agroscope. The aim was, firstly, to test the suitability of a decision support method known as Multi-Criteria Decision Analysis (MCDA) for addressing this complex problem in practice. With this approach, systems can be considered holistically: MCDA allows both the evaluative (weighting of objectives) and the descriptive elements (current knowledge on effects of various options) involved in decision‑making to be presented transparently. Secondly, based on a broad analysis of conflicting objectives and possible synergies between agricultural production and water resource protection, recommendations were to be developed identifying research gaps to be addressed as a matter of priority.

Main results of the project

• A systematic formulation and structuring of production objectives (e.g. high yields) and protection objectives (e.g. low pollutant concentrations in groundwater) within an objective hierarchy.
• A proposal for measurable indicators to quantify attainment of objectives.
• A collection of relevant measures in the area of water-friendly agriculture.
• Testing of the MCDA approach for quantitative evaluation of the effects of various measures within the whole system.
• Proposals for future research questions based on the research needs identified.
• Proposals for further application of the MCDA method in practice.

Assessment of the method

A total of 149 (primarily operational) measures were considered within the project. These were assigned to 39 groups. Together with 130 objectives, this yields 19,370 combinations for which the effects of a measure on a specific objective are to be evaluated using the relevant indicators. If experts took just two minutes for a single impact evaluation (or if computations could be performed at this speed by appropriate models), around 650 hours – almost four months’ work – would be necessary. This not only demonstrates the scale and complexity of the task, but also clearly indicates the limitations of the method when confronted with a problem of this kind.

Reference

Dietzel, A., Zaffarano, P. & Stamm, C. (2015). Zukunftsfähige gewässerschonende landwirtschaftliche Produktion in der Schweiz. Schlussbericht zum Projekt AProWa. Bern: Bundesamt für Landwirtschaft.