Ecosystem services as the silver bullet? A systematic review of how ecosystem services assessments impact biodiversity prioritisation in policy

The concept of ecosystem services and their valuation have been used extensively across the last 20 years as a means of demonstrating the immense value of nature to policy-makers. Assessing ecosystem services and assigning an economic value to them has been thought of as the silver bullet. They were expected to bring the breakthrough for biodiversity prioritisation that is sorely needed amidst the current environmental crisis. The vast figures and values attributed to nature was thought to be capable of changing decision-makers' rational minds to prioritise biodiversity in their agendas. However, to date, there has been limited research that explores how the focus on ecosystem services assessments (ESA) has impacted on policy. This understanding is profoundly needed as, despite much discussion of ecosystem services, biodiversity loss continues. To understand how policy impact is considered in ESA research and what factors enable it, this paper presents the findings from a systematic review of 137 research articles investigating ESA at the EU level (the EU is considered the trailblazer of environmental policy in the international policy arena). Of the studies captured in the systematic review, 48% of the assessments included monetary valuation methods, 62% involved experts or stakeholders and 72% specifically referred to EU, regional, national, or local policy documents. We found that 8% of the articles reported on policy impact, whilst only 8% assessed the potential enabling and 2% the hindering factors of their research to influence policy. It was evident that economic valuation, although widely used, does not necessarily lead to a higher reported policy impact. On the other hand, wide stakeholder involvement was highlighted as a key element to reach policy impact. In this paper we argue that limited coverage of impact is also partly because research on ecosystem services and their valuation, somewhat paradoxically, does not necessarily focus on the impact of these assessments. The findings thus demonstrate a need for further empirical research into the reasons for the insubstantial coverage of policy relevance in scientific reporting. The results also indicate the necessity for a review of ecosystem services valuations' actual effectiveness as a means of communicating scientific research to policy-makers. Furthermore, a wider discussion on complementary or alternative ways to upscale policy impacts is required, along with a better understanding of the target audience's needs.