The LANDFIRE (LF) fuels vegetation products describe the elements of fuels vegetation for each LF vegetation production unit. Fuel Vegetation Type (FVT) represents a modified version of Existing Vegetation Type (EVT). FVT more accurately leverages fuel transition assignments related to disturbed areas by re-establishing pre-disturbance vegetation. Linking disturbed areas to pre-disturbance EVTs allows fuel model transition assignments to properly align with logic developed from Fuels Calibration Workshops, giving more accurate representations during fire behavior analysis.
FVT was developed using the full suite of LF vegetation releases and the most recent 10 years of Annual Disturbance products. The FVT product is then evaluated through a series of QA/QC measures ensuring lifeform of the vegetation type assignment matches the lifeform of associated FVT layers.
A significant refinement to the LF Remap process for FVT and other fuel products was adopted to more accurately represent vegetation within disturbed areas for fuels use, allowing LF Remap to provide "capable fuels" products. What this means is that the Time Since Disturbance (TSD) assignments for disturbed areas have been calculated using an effective year. Year 2019 fuels, for example, may be calculated for the year 2019. This new process considers all the existing disturbances included in LF Remap and adjusts the TSD for these to the effective year (2019 in this example), making the products "2019 capable fuels."
By synchronizing TSDs for surface and canopy fuels, these refinements improve performance of fire behavior modeling and reduce the need for local LF users to update the vegetation and fuel conditions to represent current conditions when using the data operationally. LF Remap fuel products in areas mapped as disturbed within the past 10 years (disturbances since 2009) are delivered with this "capable fuels" functionality.
LF uses FVT in the development of the fuel products.