Nevada Greenhouse Gas Inventory and Reference Case Projections

FINAL Nevada GHG Inventory and Reference Case Projection
CCS, July 2007
associated forest carbon pools and the estimated flux). The sum of carbon stock changes for all
forest carbon pools yields a total net CO 2 flux for forest ecosystems.
In preparing these data, USFS estimates the amount of forest carbon in different forest types as
well as different carbon pools. The different forests include those in the national forest system
and those that are not federally-owned (private and other public forests). USFS also provides
information on forests categorized as being either woodlands (forests not used for timber
harvesting) and non-woodlands (such as timberlands).
The data shown in Table H1 are a summary of the FIA data used to derive the carbon pool and
flux estimates that are shown in Table H2. The previous inventory data came from either a
previous FIA cycle or data from the Resources Planning Act Assessment (RPA). The Resources
Planning Act requires the USFS to report on the state of US forest resources on a regular basis;
the USFS publishes the RPA assessment every five years. FIA is a key contributor to RPA. RPA
data, which are generally lower in resolution, are sometimes used in place of FIA cycles. The
FIA has transitioned from a periodic to annual sampling design, which has created some data sets
that are not comparable over time, in which case the RPA data are better suited for estimating
carbon densities. 100 As shown in Table H1, the current forest carbon pool estimates are derived
from 2005 FIA data. The previous inventory data came from a previous FIA cycle or RPA data.
Table H1. Forest Inventory Data Used to Estimate Forest CO 2 Flux
Current Inventory
Data Source
Past Inventory Data
Source
Avg.
Year a
Interval b
(yr)
Current
Forest
Area (10 3
hectares)
Previous
Forest
Area (10 3
hectares)
Forest
National Forest -
Timberland/Reserved/Low
Productivity FISDB21_NV_02_2005 FISDB21_NV_01_1989 2005.1 8.5 290 251
National Forest -Woodlands FISDB21_NV_02_2005 FISDB21_NV_01_1989 2005.1 8.5 1,126 1,041
Other Public/Private Forest –
Timberland/ Reserved/Low
Productivity FISDB21_NV_02_2005 RPAdata_NV____1997 2005.2 19.8 480 212
Other Public/Private Forest -
Woodlands FISDB21_NV_02_2005 FISDB21_NV_01_1989 2005.2 24.7 2,912 2,637
Totals 4,807 4,140
a Average year for the measurements that make up the current FIA inventory data (early 2005 for all forest types).
b The number of years between the current inventory source and the past inventory source.
The data in Table H1 show an increase of 667 kilo-hectares (1.6 million acres) in forested area
during the period of analysis (1993-2003). Over 40% of this increase occurred in woodland
forests (as mentioned under key uncertainties below, some of this difference is likely driven by
methodological differences in survey methods between the two FIA cycles).
100 Jim Smith, USFS, personal communication with K. Bickel, CCS, November 7, 2006.
Nevada Division of 68 Center for Climate Strategies
Environmental Protection
www.climatestrategies.us