Sierra Nevada Biomass Volume

This metric expresses the total amount of existing biomass volume (measured in dry weight tons per acre) from all live tree crowns (branchwood and foliage) and the tree stems less than 10" dbh for the Sierra Nevada region. This metric can be used to assess the volume of biomass present at the 30m cell level. It is recognized in some forest types, shrub biomass can be a significant contributor to the total biomass, however due to the aforementioned limitations of the F3 model, the shrub component has not been included.

Data and Resources

Additional Info

Field Value
Version Version 5.0
Last Updated March 28, 2025, 08:35 (UTC)
Created March 7, 2025, 07:52 (UTC)
category /Economic Diversity/Wood Product Industry
collection_name California Landscape Metrics
creation_method The F3 model generated several raster surfaces to provide an estimate of the total aboveground live tree crown (including foliage) biomass for all trees (ABGDLVBR) and estimates of the tree stem biomass of live small trees (BMSTM; <10" dbh). Since the F3 model data is driven by FIA plot data (which is an incomplete source for shrub metrics), the shrub biomass cannot currently be generated. 2019 to 2021 Update: Values for 2021 were adjusted using the Ecosystem Disturbance and Recovery Tracker (eDaRT), described in the Introduction. All eDaRT events beginning August 1, 2019 through November 30, 2021 were identified, and the corresponding Mortality Magnitude Index (MMI) values for these events was summed, giving the estimated fractional canopy cover loss per 30m pixel over that time period. Values for each non-overlapping predefined small tree size class for stemwood biomass (BMSTM_x) raster and for the total aboveground live tree crown biomass for all trees (ABGDLVBR) raster were adjusted for 2021 following the same procedure using eDaRT MMI. The MMI value for canopy cover loss was used as a direct proxy to estimate biomass loss using the MMI percent adjustments, e.g.: _2021 BMSTM_x = 2019 BMSTM_x '€“ (2019 BMSTM_x * MMI/100)_ Although the assumption of direct correlation between canopy cover and biomass should be viewed with caution, it serves as a reasonable approximation for representative mixed conifer forests in the Sierra Nevada affected by the recent drought (Slaton et al. 2022). The assumption that canopy cover loss, as estimated using eDaRT MMI, was equitably distributed among predefined size classes may result in over- or under-estimates of actual small tree stem biomass, depending on location. This layer for the available Biomass metric is derived from F3 layers (2021) using the following formula: _sum(ABGDLVBR, BMSTM_0, BMSTM_2, BMSTM_7)_
data_resolution 30m Raster
data_units Dry weight tons/acre
data_vintage 2021
date_updated August 2024
element Wood Product Industry
encoding utf8
file_name SNV_AvailableBiomass_202111_202209_T2_v5
format GeoTiff
harvest_object_id 71d73afb-478f-4f8b-be26-441a5cc79dc6
harvest_source_id a2637971-af12-457f-ae4a-831d2202a539
harvest_source_title WIFIRE Commons
maximum_value 272.0
metric_definition_and_relevance This metric expresses the total amount of existing biomass volume (measured in dry weight tons per acre) from all live tree crowns (branchwood and foliage) and the tree stems less than 10" dbh for the Sierra Nevada region. This metric can be used to assess the volume of biomass present at the 30m cell level. It is recognized in some forest types, shrub biomass can be a significant contributor to the total biomass, however due to the [aforementioned limitations](https://docs.google.com/document/d/15tXCMkEzUEgQKHoXL74cftwtLuz3z-Rm/edit#heading=h.4d34og8) of the F3 model, the shrub component has not been included.
minimum_value 0.0
pillar Economic Diversity
spatial {"type": "Polygon", "coordinates": [[[-122.2883616476824, 35.05769372687348], [-117.5563290826801, 35.05769372687348], [-117.5563290826801, 42.00332292672577], [-122.2883616476824, 42.00332292672577], [-122.2883616476824, 35.05769372687348]]]}
tier 2