Mapping of a field: A systematic review of reviews on forestry and the forest-based sector in Europe

This study applies PRISMA guidelines to map and analyze trends and patterns in evidence synthesis within the field of Forestry and Forest-based Sector (F&FS). Given the role of evidence synthesis in shaping research priorities and informing policy, the study investigates potential biases in evidence synthesized by examining different forms of synthesis (i.e. systematic and non-systematic), topics covered and geographical distribution of underpinning studies. Following a thorough expert-led classification of F&FS topics, we identified 35,015 reviews from Europe, of which 642 were systematic. Although rapidly growing, systematic literature reviews (SLRs) still account for under 1% of all scientific production in F&FS (∼5% of all evidence synthesis). Reviewed topics are dominated by management, biodiversity and climate change, even though the field is sprawling away from core silviculture themes and into more transdisciplinary issues. However, SLRs are more abundant in health-related and social science topics compared to non-systematic reviews, while syntheses of forest technologies and forest products are underrepresented. We also find an uneven geographical distribution of systematized evidence, South-eastern Europe the least and Mediterranean-Northern-Western Europe the most represented. Factors best explaining observed patterns are investment in Research & Development and economic contribution of value in million US dollars added in the forest sector. Our results show evidence synthesis within the F&FS field comes with structural biases in selected research themes, geographical distribution, and methodological approaches. The resulting partial understanding of the knowledge base may influence not only scientific agendas but also policy priorities, assuming such evidence is taken up by policymakers.