Overview of the main challenges for comprehensive forest monitoring in Europe

Abstract

Comprehensive forest monitoring systems are crucial for supporting effective forest management and policy development and target setting. The new European Union (EU) Forest Strategy for 2030 calls for the development of an EU-wide integrated forest monitoring framework. This framework should address the patchiness of the current inventory systems, which includes national, EU, and international initiatives, expand the scope and overcome other challenges related to the systems currently in place. To identify the main challenges in developing a comprehensive forest monitoring for Europe, we reviewed more than 60 scientific papers, books, reports, and legislation and identified over a hundred issues that represent obstacles to harmonization and a holistic European system. Subsequently, we classified these issues into problem categories, which represent the main challenges for forest monitoring in Europe: (i) comparability: since most national forest inventory systems are developed independently, their definitions, time coverage, plot density, or resolution often differ in a way that data are not easily comparable, and datasets need harmonization to achieve the necessary comparability (ii) quality: assessment quality may differ between indicators within a forest inventory, or for the same indicator between forest inventories. This is influenced by differences in plot measurements, plot density or the number of plots over an area, and to which extent earth observation is included in the methodology (iii) transparency, accessibility, and dissemination: access to forest inventory data is mostly limited across European countries, including restrictions on in-situ plot data availability. The disseminated data is often expressed in a format that poses challenges in terms of usability and interpretation for different types of users (iv) indicator coverage: national forest information systems often lack a holistic approach and topics such as biodiversity and bioeconomy are not sufficiently covered. The development of comprehensive EU-wide forest monitoring and information system(s) has multiple motivations and is undoubtedly part of an ongoing political debate. Several ongoing projects are actively working towards addressing these obstacles. As the aforementioned problems differ in terms of their drivers, significance, and impacts, it is vital for the success of initiatives aimed at developing harmonization approaches to address solutions across all problem categories.