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Home Spatial Analysis and Modeling Galena Forest (Biomass) Inventory and Long-term Sustained Yield Planning

Galena Forest (Biomass) Inventory and Long-term Sustained Yield Planning

In late January, 2013 Geographic Resource Solutions (GRS) released the This report describes the detailed vegetation/land cover/biomass inventory developed for approximately 1.25 million acres of wildlands in the vicinity of Galena that was used to estimate forest growth and biomass availability and project the magnitude and sustainability of future harvest levels through the end of this century. It represents the combination of field data collection, image classification, growth projection, harvest scheduling, and long-term sustained yield planning services, all performed by GRS.  The resulting information provided the basis for a determination of the feasibility of developing biomass fueled power generation for the community of Galena. This Project was funded by grants from the Alaska Energy Authority and the Bureau of Land Management.

The city of Galena is located about 480 miles up the Yukon River in interior Alaska. Galena is off the Alaska power grid and dependent on outside sources of petroleum-based fuels for the production of heating and electricity. In early 2012 GRS was chosen to conduct a forest inventory study within a 25-mile radius of Galena (Galena Vicinity) to develop a biomass inventory, and provide a sustainable harvest scheduling plan to potentially utilize potentially available biomass for local energy production.

GRS reviewed vegetation inventory data available for the Galena area and determined that data collected on the two nearby Innoko and Koyukuk wildlife refuges by Ducks Unlimited (DU) in the late 1990’s-early 2000’s would be the best available resource information to use as a foundation for inventory efforts. GRS then used recent (2009-2010) Landsat 5 satellite imagery to stratify the Galena Vicinity and identify potential field training sites. GRS field crews then visited 63 forest sampling sites at which they collected detailed resource information that were used to verify, refine, update, and replace portions of the DU data set. The updated data set was then applied to the Landsat 5 imagery using GRS’s Discrete Image Classification methodology to generate image classification maps. These maps were then aggregated to produce a site-specific Stand Inventory polygon map data set of Viereck classification types and associated species-specific biomass estimates for all lands in the Galena Vicinity (see maps below).

The resulting Stand Inventory was associated with different landscape and cultural characteristics of the Galena Vicinity and was evaluated to develop an estimate of Available Biomass Inventory. A site-specific Harvest Unit map data set was then developed and five harvest plans (Options) were generated using GRS’s modeling application harvestBiomass to project long-term sustained yield levels for the Galena Vicinity. All five alternative plans met the maximum stated target of 20,000 dry-tons per year for the projection period (2013-2110), however the different alternatives reflected different levels of annual biomass procurement cost that ranged from approximately $1.56 million to $1.92 million per year. The major cost component of these management plans is Transportation Costs, which ranged from 59% to 70% of the total biomass procurement costs. The estimated cost/ton of harvested biomass ranges from just under $78/ton to over $94/ton depending on the harvest option.

The different harvest scheduling scenarios represented different levels of harvest intensity near Galena and the Yukon River; acreage harvested and reforested; winter and summer season transportation; transportation system development; and environmental impact. Options can be ranked by benefits and costs, but non-market values may play a significant role in which option best fits the community.

The follow map from the project report shows the Galena Biomass Inventory in the vicinity of Galena, AK.  While it basically is displayed as a color-coded type map, the map data set attributes store much more detailed species-specific information about each individual mapped stand than just the major vegetation/land-cover type.

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The following image from the Galena map data set shows the detailed biomass inventory attributes developed for each stand (polygon) of the Galena Inventory.  These attributes include estimates of cover by species and major species group and lifeform, as well as dry-tons/acre, quadratic mean diameter, trees/acre, height, and cubic volume/acre for conifers, hardwoods, and in total for all trees and for trees in the top (bird's-eye) canopy layer.

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For further information regarding GRS's forest sampling techniques, image classification methodology, biomass inventory, growth estimation techniques, or harvest scheduling/projection please contact Ken Stumpf at GRS’s Arcata, CA office.

 

 


GSA# GS-10F-0451NESRI Consultant