PNW-FIA Interior Alaska Inventory

Project Description

Forest Inventory and Analysis is a consistent, national monitoring program covering all forest ownerships. We work with land managers as partners to provide a wealth of data that crosses management boundaries, just as disturbance, climatic events, and forest changes span boundaries. Together we answer questions to help sustain our forests and the communities that depend on them:

1. What are the effects of climatic variation, fire, insects, and disease on the boreal forests of Alaska?
2. Are Alaska’s forests carbon sinks or sources?
3. How have rates of tree growth and mortality changed over time?
4. How much biomass do Alaska’s forests contain?
5. How much carbon and nitrogen are stored in Alaska’s soils and ground cover mats?
6. What is the distribution and extent of forage lichens across Alaska?
7. How are Alaska tree species distribution and composition changing?
8. What are the dynamics of fire effects and recovery in Alaska?
9. How resilient are Alaska’s boreal forests?
10. How is the extent of surface water in boreal forests of Alaska changing over time?
11. What is the rate and extent of forest cover change (tree growth, height, diameter) and expansion of woody vegetation at tree line?
12. What is the nature and severity of disturbances, including mortality and defoliation owing to increased insect activity in Alaska’s forests?

Interior Alaska Inventory

The Interior Alaska Forest Inventory & Analysis project was launched by the PNW Research Station’s Forestry Sciences Laboratory in Anchorage, Alaska, in collaboration with the State of Alaska Department of Natural Resources, Division of Forestry, NASA, and other collaborators. This new project will inventory the remaining 15 percent of U.S. forested land not yet covered in the FIA sample. The Interior Alaska effort will install about 4,800 new FIA plots on the ground over approximately 25 years and supplement this data utilizing cutting edge remote sensing techniques (NASA’s G-LiHT system).

• Full project implementation began in 2016. State of Alaska Division of Forestry field crews, with support from Forest Service employees, collect field plot measurements each summer.
• In 2018 crews completed over 800 plots to finish the first unit of the Interior Alaska FIA, the Tanana Valley unit. In 2020 crews completed just under 400 plots to finish the Susitna-Copper unit.
• Remaining units to be inventoried include the Southwest, Lower Yukon, Upper Yukon, and North Slope (see map below).
• The complete Interior inventory of approximately 4,800 plots is expected to take up to 25 years before entering remeasurement phase.
• Field crews base operations out of small Alaskan communities and engage with the public through citizen science and other outreach activities.

PNW FIA Alaska survey unit boundaries. Blue dots represent plots in the interior survey. The plot locations depicted are approximate.

Purpose and Scope

Forest Inventory and Analysis (FIA) is a national U.S. Forest Service program that monitors forest resources on all lands – public, private, and tribal. FIA monitors forests in all 50 states, including southeast and Interior Alaska. Alaska is the largest state in the U.S., covering more than 600 thousand square miles. Until the introduction of the Interior Alaska FIA program in 2016 only 16 percent (15 million acres) of Alaska’s forests statewide were included in forest inventory through the coastal Alaska FIA program in the southeast region. The state’s interior boreal forests are vast, spanning approximately 113 million acres and representing 15 percent of total U.S. forest land. Although these forests play a significant role in supplying natural resources to local Alaskan communities and in sustaining global energy, water, and carbon cycles, they were not previously inventoried as part of the FIA program, making them the last U.S. forest type to be formally inventoried. Previously, lack of transportation infrastructure and funding prohibited our ability to monitor the critical forests of Interior Alaska. The U.S. Forest Service sought help from local communities and the state of Alaska, as well as high-tech innovations developed by NASA to pilot a new way of monitoring forest resources in remote areas. After a successful partnership on a Tanana Valley pilot project in 2014, we are now working together to collect data on 300 field plots per year in Interior Alaska.

Methods

Inventory methods consist of standard Nationwide Forest Inventory (NFI) data collection protocols with enhanced vegetation, lichen and moss ground cover, soils and tree ring measurements specific to the boreal forests of Interior Alaska. PNW FIA scientists continue to cooperate with NASA and the next generation of Goddard’s LiDAR, Hyperspectral and Thermal Imager (G-LiHT). The G-LiHT sensor suite enables integration with field data acquisition for model assisted landscape classification and vegetation attribute estimation like forest biomass and carbon sequestration.

The specific instructions for FIA Data Collection can be found in the FIA Data Collection Field Manuals. (See Resources tab.)

Project Deliverables

Interior Alaska inventory data has been joined with coastal Alaska inventory data into a SQLite database that can be found here.