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fuego
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Los bosques tropicales húmedos del norte de Suramérica almacenan gran parte del carbono terrestre global y albergan una gran biodiversidad, pero las transiciones entre incendios, degradación y deforestación, y el efecto de la gobernanza territorial sobre ellas, siguen sin cuantificarse sistemáticamente. En este estudio caracterizamos las trayectorias posteriores a los incendios (2001–2024) de bosques en las cuencas del Amazonas y del Orinoco de Colombia (CO) y Venezuela (VE) que no presentaban señales de perturbación para el año 2000. Integramos los productos de área quemada ESA CCI Fire (250 m, 2001–2020) y MODIS MCD64A1 (500 m, 2021–2024) con el producto JRC TMF AnnualChanges (30 m) y seleccionamos una muestra de píxeles con detección de quema para seguir su estado año a año. En 2024, el 69 % de la muestra seguía apareciendo como bosque no perturbado, con un contraste marcado entre países: Colombia presentaba una mayor proporción de deforestación (14,6 % frente a 6,3 % en Venezuela) y Venezuela una mayor proporción de degradación (21,7 % frente a 17,5 %). El 62 % de la deforestación en Colombia y el 77 % en Venezuela habían transitado por el estado de degradación previa, con latencias medianas de cinco y seis años (quema a degradación) y de tres y seis años (degradación a deforestación). En la Amazonía colombiana sin protección formal, el 23 % fue deforestado, frente a la ausencia de deforestación en los bosques donde se superponían áreas protegidas y territorio indígena. La cascada de fuego, degradación y deforestación fue la trayectoria dominante, y la coexistencia de gobernanza estatal e indígena se asoció a una menor pérdida de cobertura forestal por fuego.
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