Forest Biomass Mapping in California and Western Oregon

Project summary

In this project, we are continuing the development of an integrated system for monitoring forest carbon and biomass dynamics (see CMONster project) in California and Western Oregon. This system leverages USDA Forest Service Forest Inventory and Analysis (FIA) data and fitted Landsat imagery based on the LandTrendr algorithms. In particular, this project incorporated satellite imagery from multiple Landsat missions (Landsat 5, 7, and 8) and 16 years of FIA plot data to understand the patterns, causes, and consequences of biomass stock status and change, especially as it related to forest disturbances (e.g., drought-induced mortality, wildfire, etc.). Additionally, this work aimed to better understand uncertainties in resulting forest biomass maps to inform their use by land managers, policy makers, and scientists.

The GNN mapping component of the monitoring system, which includes several variations of GNN maps of aboveground live forest biomass as well as an assessment of uncertainty based on these realizations, will be applied for imagery years 1990 to 2016.

GNN Map Products for California and Western Oregon

From this project, we provide 2016 aboveground life forest biomass (Mg/ha) based on three versions of GNN:

• nearest neighbor (i.e., k=1)
• bootstrap approximation
• the unweighted mean of the 10 nearest neighbors (i.e., k=10).

To download these maps, see the links below. Maps for other years (1990-2015) are also available upon request. For the bootstrap approximation and k=10 versions, we also have standard deviation rasters available upon request. For either of these products, please contact us. Only aboveground live forest biomass is available for this project (please see our main data page for other GNN products).

Product Description	Status	Imagery year	Date posted	Download
Aboveground live tree biomass (k=1)	FINAL	2016	09/20/2018	(425 MB)
Aboveground live tree biomass (bootstrap approximation)	FINAL	2016	09/20/2018	(500 MB)
Aboveground live tree biomass (k=10)	FINAL	2016	12/30/2019	(493 MB)

Collaborators and Support

Research collaborators include John Battles, John Sanders, and Brandon Collins (University of California Berkley); Robert Kennedy (Oregon State University); David Saah (University of San Francisco); Zhiqiang Yang (USDA Forest Service Rocky Mountain Research Station); the Forest Inventory and Analysis (FIA) Program, Pacific Northwest Research Station (PNW), USDA Forest Service; and Andrew Gray (PNW FIA). The research was supported by the California Climate Assessment through the California Natural Resources Agency and the Oregon Department of Forestry.

Publications, Reports, and Presentations