Seeing the wood for the trees with advanced sensing technology

As part of what has been called the ‘green infrastructure’, Europe’s forests are at the forefront of competing drives. They fulfil various functions including: the supply of raw materials for energy production, carbon sequestration to offset greenhouse gas emissions, provision of sanctuary for biodiversity conservation, and water protection, as well as offering recreation opportunities.

As demands for each use increase so EU policies, regulatory frameworks and reporting requirements strive to keep up. Indeed, forest management cuts across a range of sectors, each with their own data standards and processes, making effective resource management problematic.

The need for better forest health and vitality assessments, as well as to make information readily available to end-users, is recognised by the Green paper of the European Commission and in the new EU Forest Strategy. The EU-funded project, DIABOLO, was set up to contribute to efforts to develop a sustainable European bioeconomy.

The state of play in data collection

Effectively monitoring the status of forests currently usually involves an assessment of ‘disturbances’ and ‘degradation’. Disturbance typically refers to depletion of biomass or crown cover caused by one-time natural events, such as storms or fires. Whereas, degradation references human-induced impact, usually occurring over a longer time period, involving continuous or repeated events. The DIABOLO team have pointed out that previous efforts to monitor forests focused on the more straight-forward mapping of deforestation and regeneration. ‘Time series analysis’ is now perhaps regarded as the approach to forestry information gathering and mapping which yields the best operational data. But it does come with its own challenges.

A recent review of the state of play by members of the DIABOLO project team, published by Current Forestry Reports, outlines some of the problems inherent in information gathering and processing. The team analysed mapping options for Europe’s temperate forests and Africa’s tropical evergreen forests. They found that tropical forests are under more pressure than temperate forests, with only 24 % of tropical forests in a mature and relatively undisturbed state.

The review however also highlights the fact that there is variance in the range of available data values, reflecting the challenges in making accurate forest degradation assessments. They caution that with a plethora of information gathering sources, the danger is for resultant data to be fragmented and partial, restricting its usability. They give the examples of varying nomenclature across assessments and the limitations of total area figures (for example being restricted to national level).

Towards data harmonisation for better management

DIABOLO’s mission is to contribute to what the team have referred to as data ‘harmonisation’. They point to advanced remote sensing technology such as the European Space Agency’s Sentinel-2 polar orbiting satellite launched in 2016, as being able to facilitate the necessary standardisation. High resolution, optical data such as this can provide near real-time, geo-located and accurate information needed for decision-making.

In their paper the team also call for more focus on the classification of disturbance types (such as fire, storm, selective logging etc.) as well as more robust up-scalable mapping efforts. They also point to a need for longer term, regional and global disturbance observation capacity.

Referring specifically to tropical forest monitoring the authors reference another ongoing EU funded project, EOMonDis, which is aiming to offer operational Earth Observation (EO) services for better tropical forest management and reporting.

For more information, please see:
project website DIABOLO
project website EOMonDis