Producción CyT

Validation of GEDI above ground biomass product over Pinus sp. plantations in Argentina

Articulo

Autoría:

Grings, Francisco ; Leszczuk, Andrés ; Hildt, Eduardo ; Lorán, Damián ; ARELLANA, JAVIER ENRIQUE ; Orona, Martín ; López, Hugo ; Kornuta, José ; Ottenweller, Cristian ; Breziski, Dario ; Silva, Horacio ; Rechberger, Fabián ; Franco, Mariano

Fecha:

2025

Editorial y Lugar de Edición:

SPIE-SOC PHOTOPTICAL INSTRUMENTATION ENGINEERS

Revista:

JOURNAL OF APPLIED REMOTE SENSING, vol. 19 SPIE-SOC PHOTOPTICAL INSTRUMENTATION ENGINEERS

Resumen *

In recent years, in addition to the traditional uses of forest plantations, there hasbeen an interest in their capacity to capture and fix carbon in their structures, actingas greenhouse gas sinks. The Global Ecosystem Dynamics Investigation (GEDI)project features a light detection and ranging sensor aimed at quantifying the distribution of biomass and carbon in woody vegetation worldwide. Although the GEDIlevel 4A product (L4A) generates aboveground biomass density (AGBD) estimateson a global scale using semi-empirical relationships between the energy reflected ata given height (rh metric) and AGBD, its forest segmentation is coarse and presentslimitations at a local scale, which can result in less accurate estimates. We evaluatedthe accuracy of GEDI L4A AGBD estimates and in situ AGBD data obtained fromforest inventories. The analysis of the relationship between in situ AGBD and GEDIL4A product AGBD estimates shows that, although the correlation is generally good,some plots exhibit high variability in GEDI AGBD values despite having intermediatevalues of in situ AGBD [root mean squared error (RMSE) = 89.1 Mg/h]. Moreover, wefound that these underestimations are associated with low values of rh50. In particular, these low values of rh50 (related to large AGBD RMSE errors) were not related tothinned/non-thinned forests but were related to understory conditions (less error forthe “very dense” understories). Then, we explored landcover misassignment; as thePinus sp. plantations correspond to implanted North American evergreen needleleafforests (ENFs), we reconstructed the L4A product for this region and South America,using the corresponding expressions to estimate AGBD. The results show animprovement in the overall correlation and a reduction in errors, with RMSE reducingto 68.4 Mg/h for South American ENF and 64.2 Mg/h for North American ENF.Finally, we discuss ways to improve AGBD estimations (or flag wrong ones) usingall available values of the rh curve. Información suministrada por el agente en SIGEVA

Palabras Clave

rh metricsGEDI L4Asemi-empirical modelforest inventory