Using inventory data as a proxy de delimit forest degradation Joint GFOI/GOFC-GOLD Expert Workshop 2: Approaches to monitoring forest degradation for REDD+ Using inventory data as a proxy de delimit forest degradation Ben H.J. de Jong; Jesus Trujillo El Colegio de la Frontera Sur Wageningen, The Netherlands 1-3 October, 2014

Objectives 2 To develop reference scenarios at different scales, based on historical trends

Project background 1.The research is being carried out in Mexico, with special emphasis on lowland tropical forests. 2.The work is based on identifying the effect of reported disturbances on forest structural parameters (based on inventory data) and to relate these to RS time series and derived disturbance indices. 3.The initial work to identify the relation between reported disturbances and standing biomass was published in: Carbon Management (2013) 4(6), 601–615. We use the Vegetation Change Tracker algorithm, developed by Healey et al (2005), which is based on the normalized spectral distance of any given pixel from a nominal “mature forest” class to a “bare soil” class. It is based on a continuous metric related to gain or loss of biomass, rather than a “hard” classifier. The Disturbance Index is a transformation of the Landsat Tasseled-Cap data space (Masek et al, 2008)

Data and resources used National inventory data of about 22,000 sites, sistematically distributed over forested areas, all measured between and re-measured between Data include measurements of trees, shrubs, etc and visible evidence of disturbances in five classes: not present, very light, moderate, medium, and severe. National database of biomass equations, to convert inventory data to biomass. National LULC maps. Landsat time series from the 1990s to present Modis-derived parameters of vegetation (not incorporated yet). 4

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Methodological approach Create maps of disturbances, reported in the National Forest Inventory

Correlate disturbance intensity with forest structural data, such as standing biomass, basal area, stand-height. 8

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Fire in tropical lowland forests 10

De Jong, in press

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Plot with severe fire in Reported fire disturbance Reported grazing disturbance (after forest fire) VCT Dist. Index Dist index trajectory of pixel Date of NFI Create time series of disturbances from satellite imagery, validated with NFI and permanent plot data No forest Dist forest Undist forest Cloud

14 VCTDI Dist. index trajectory of pixel Undisturbed plot

DI Plot recovering from previous disturbance

Example of deforestation time series 16

In progress: Defining degradation boundaries of Disturbance Index (validated with permanent plots and NFI data). Validate rates of recovery (e.g. Aryal et al 2014) derived from VCT, permanent sampling plots and NFI 17

Develop emission scenarios at various scales 18

Technical Challenges 1.Requires good geo-referenced ground data on disturbances and their effect on forests 2.The methodology requires time series of RS and ground data 3.We adapted our methodology on the availability of data and infrastructure

R&D requirements We are aware that recording the effect of forest degradation on carbon dynamics requires an efficient approach to combine ground data with RS data. Ground data are required to identify the type of disturbance and if it effects forest structure. With RS time series disturbance and recovery trajectories can be developed at the level of pixel or pixel groups. We are developing procedures that efficiently relate ground-data collection procedures with RS information, not only to obtain information on the effect of forest disturbances on forest structural parameters but also on the rate of recovery after the disturbance occurs.

Rate the importance of the following with respect to your R&D activity High-Med-Low Access to free satellite data and archives for R&DHigh (time series) Provide input to SDCG/space agencies to ensure systematic acquisitions of consistent satellite data High New research partnerships and coordinated response to open calls for funding High Assist in capacity building and technology transfer in REDD countriesHigh Discussions at political level to encourage support of the scienceMedium Future contribution to GFOI Methods and Guidance Documentation and GOFC-GOLD Sourcebook High Participation in future targeted workshops such as this oneMedium Participation in an Annual Science Meeting with open invitation to government/industry/academia/research partners Medium Coordination between forest inventories and RS peopleHigh