Summary

SAPPHIRE is a collaborative project between Rezatec and Forest Research, which explores whether data from earth observation satellites can be turned into an effective tree-health mapping and assessment tool. It focuses on aggregating diverse datasets, from satellites and other sources, to produce precision maps that enable tree health practitioners to accurately identify different tree species and to pinpoint trees that may be exhibiting stress associated with tree health problems.

Research Objectives

Phase I (August 2015 – March 2016)

• to analyse data from various EO sensors in combination with existing ground-based and accessory data, to map the distribution and abundance of oak and ash at selected study sites;
• to use trees’ typical annual phenological pattern as a means of distinguishing oak from ash;
• to develop a method to differentiate broadleaved trees that may be exhibiting stress associated with tree health disorders; and
• to make results available through Rezatec’s geospatial data web portal.

Phase II (September 2016 – March 2017)

• to expand the analysis undertaken in the Phase I project to an expanded range of tree species and sites;
• to further validate the Phase I project results for oak and ash against known tree health information; and
• to develop the commercial potential of using satellite data analytics by bringing new tools to market, through Rezatec’s geospatial data web portal, that will enable users to view tree health information alongside other inventory information, such as species distribution, tree height and windblow damage.

Results so far

Phase I (complete)

• Data from various EO sensors (Sentinel 1 C-band SAR, Sentinel 2 multi-spectral sensor and Landsat 8) were analysed in combination with existing ground-based and accessory data (LiDAR and National Forest Inventory), and integrated using data mining approaches.

• Results were very encouraging, with tree species maps achieving a minimum classification accuracy of 80%.
• Rezatec also developed a method to differentiate broadleaved trees that may be exhibiting stress associated with pathogens.

Phase II (complete)

• Target tree species and study sites have been selected.
• The process of verifying Phase I results is underway.

Status

Phase I: August 2015 – March 2016

Phase II: September 2016 – March 2017

Contact

Alison Melvin

Funders and partners

This project is funded by the ‘Space for Smarter Government Programme’ (SSGP), a strategic, national programme established and led by the UK Space Agency, and delivered in collaboration with the Satellite Applications Catapult, to drive the uptake and use of space products, data and services across government departments.

The project is co-ordinated by Rezatec, a leading UK geospatial data analysis company, headquartered within the UK Space Gateway in Oxfordshire, that has expertise in aggregating large amounts of diverse data from satellite, airborne and ground instruments, to produce geospatial data.