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Disturbance events such as fire have major effects on forest dynamics, succession and the carbon cycle in the boreal biome. This paper focuses on establishing whether characteristic spatio-temporal patterns of the fraction of Absorbed Photosynthetically Active Radiation (fAPAR) occur in the initial two years after a fire event in Siberian boreal forests. Time-series of MODIS fAPAR were used to study post-fire dynamics during the year of the fire and the following two years. Three forest types (evergreen needle-leaf, deciduous needle-leaf and deciduous broadleaf) grouped into three latitudinal regions, ranging from 51° N to 65° N, were studied by analysing a sample of 14 burned areas. For each of the burned areas an adjacent unburned control plot was selected with the aim of separating inter-annual variations caused by climate from changes in fAPAR behaviour due to a burn. The results suggest that (i) the forest types exhibit characteristic fAPAR change trajectories shortly after the fire, (ii) the differences in the fAPAR trajectories are related to the forest type, (iii) fAPAR changes are not significantly different among the latitudinal regions, and (iv) the limited temporal variability observed among the 3 years of observations indicates that fAPAR varies very little in the initial years after a fire event. [ABSTRACT FROM AUTHOR]

An empirical estimation of live fuel moisture content (FMC) was generated from National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) derived variables. This estimation was based on the ratio of Normalized Difference Vegetation Index (NDVI) and surface temperature ( T s ), and the relative greenness (RGRE). It was derived for the summer season (from June to September). The estimation was calibrated from field measurements collected in central Spain, and included consideration of both herbaceous and shrub live FMC values. The proposed estimation worked reasonably well for other periods in the same study area and also for other similar study areas in Mediterranean environments. This estimation of FMC from remote sensing could be used as an input to standard fire danger and fire behaviour programs, providing spatially comprehensive data, which is critical for regional planning of fire prevention. [ABSTRACT FROM AUTHOR]