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Data Information and Reporting for Indicator G.a.
Oregon Indicator of Sustainable Forest Management G.a.
Carbon stocks on forestlands and in forest products
 
Forestry Program for Oregon Strategy G:
Indicator G.a. is the single indicator that will measure progress towards achieving Forestry Program for Oregon Strategy G: Enhance carbon storage in Oregon's forests and forest products.

Desired Trend
Rates of carbon sequestration and storage in Oregon forests and forest products are stable or increasing.

At-a-Glance: Condition, Trend, and Information
The Oregon Roundtable on Sustainable Forests has completed an initial evaluation of this indicator report but has not yet developed conclusions on ratings for Condition, Trend, and Quality of Information.  Once that step is completed, this section will display symbols that at-a-glance illustrate the condition, trend, and quality of information available for this indicator. 
 

Why is this indicator important?
Through the use of this indicator, forest managers, policy-makers, and the public will be able to see the changes in the carbon sink capacity on the state’s forestlands from the interaction over a given period of time of disturbance, land use change, forest management, and forest product manufacture efficiency and utilization.  By comparing indicator results over successive time periods, one can learn if forest policies and actions are maintaining or enhancing the carbon sink capacity of Oregon’s forestlands over time.

What does this indicator tell us about sustainable forest management?
Condition:
The analysis for this indicator shows that Oregon’s forest sector (forests and forest products) currently stores approximately 3,744 Teragrams (1012 grams) of carbon.  Depending on disturbance and growth patterns, forest ecosystems can be either a source of carbon to the atmosphere or a sink that stores carbon from atmosphere.  Estimates from the trend analysis indicate that Oregon’s forest sector may currently be an overall sink of carbon from the atmosphere. 
 
With 2008 as a reference year, the average carbon stores associated with each of the four test regions examined for the indicator show that the average carbon storage, expressed in Megagrams (106grams) per hectare, was 308 for the Klamath, 529 for the West Cascades, 347 for the East Cascades, and 310 for the Blue Mtns.  For the 2004-2008 time period the West Cascades appears to be the only region that is a source of carbon to the atmosphere, although that condition is likely to change if reduced harvesting continues in that region.  The Klamath region appears to be in a carbon balance, whereas the East Cascades and Blue Mtn’s are likely weak carbon sinks.
 

Trend:
The estimate of overall carbon storage in Oregon’s forest sector has generally decreased from 1960 to today, although there may have been some stabilization in most recent years in carbon stores.  Carbon fluxes in the forest sector appear to have been negative most of the 1970 to 2005 period, indicating that the Oregon forest sector has been a net source of carbon to the atmosphere.  Since that time fluxes have been neutral to slightly positive, indicating the system may be switching to a sink from the atmosphere.
 

Information
A disturbance history database was integrated with the LandCarb 3.0 forest simulation modeling system to simulate the accumulation of forest carbon over the 1961-2008 time period.  The forest carbon simulations were conducted in four subregions  of Oregon. Three sources of information were used to generate a database of information representing the history of forest disturbances.  These sources of information include 1) a Gradient Nearest Neighbor-derived map representing forest age.  The forest age map allowed the creation of disturbance history prior to 1972, 2) a five-year periodic disturbance database for the 1972-1982 period created from a change detection comparison of Landsat images, and 3) an annual disturbance database for the 1982-2008 period.  This third database was generated from the interpretation of multiple years of Landsat satellite imagery with the LandTrendr (Landsat Detection of Trends in Disturbance and Recovery) (Kennedy et al. 2007) analysis system.
 
Remote sensing images were not available for some years in three subregions.  For the years when this data was not available, estimates for carbon flux were not made.  Consequently, the graphics representing forest carbon flux have broken trend lines at the years when the data is not available.   
 
Statewide reporting for this indicator is not yet available.  However, coarse estimates may be extrapolated from the four forested subregions reported and plans are in place to expand the current analysis to a fifth subregion located in the North Coast.  Estimates for all subregions may be revised as the modeling methodology is further refined.   

Research Introduction and Background
The methods and results of a preliminary analysis based on remotely sensed forest age and disturbance data layers and the LandCarb simulation are presented, including spatial databases for the stores and fluxes (i.e., net changes in time) of major carbon pools including, live, dead, soil, and forest products, as well as totals of all these pools.
 
We anticipate that additional work will be required to check all the generated databases against inventory and other field data to improve model parameterizations as well as to improve the pre-1970 land-use and disturbance history that required to “spin-up” the simulations. This work will continue under a NASA funded effort over the upcoming year.
 
In this project, integrated remote sensing and computer simulations are used to monitor trends in actual carbon dynamics in Oregon’s forests. This will help meet Oregon’s commitment to carbon accounting and reporting through the Montreal Process. This work will eventually be used to detect and quantify changes in forest carbon stocks (including fine-scale changes) on all forestland, assist in tracking changes in carbon offset projects, and allow Oregon to examine the potential for alternative management systems to increase carbon sequestration. The current information in this report describes the first phase of using this system.
 
More information on the integrated remote sensing databases and the LandCarb simulation modeling can be found in the actual final report on forest carbon store and flux in Oregon that was completed by Oregon State University in December 2009.

Study Areas
The initial study work was concentrated on four areas that reflect the diversity of Oregon's forests (Figure 1).
  1. the Klamath region of southwestern Oregon where mixed conifer forests dominate and there has been a recent increase in wildfires;
  2. the central western Cascades region, which holds significant carbon-sequestration potential, and which is a major timber producing area dominated by Douglas-fir/western hemlock;
  3. the high Cascades and eastern Cascades, which are dominated by true firs, Douglas-fir, and ponderosa pine, and which have seen significant recent insect and fire-related mortality; and,
  4. the Blue Mountains of eastern Oregon, which include a range of forest types typical of the interior west, with a similar mix of fire and insect activity and a diversity of harvest intensities and goals.
 
Figure 1
 
Study Area
 

Hemlock/sitka spruce group Pinyon/juniper group
Douglas-fir group Ponderosa pine group
Western oak group Lodgepole pine group
Tanoak/laurel group Fir/spruce/mountain hemlock group

Preliminary Analysis of the Four Regions
 
An example of a stores grid for 2005 for the West Cascades region is illustrated in Figure 2.
 
Figure 2
 
 
Areas in white are lands without forest (i.e., agricultural lands or water). Maximum carbon stores in this area are estimated to be 834 MgC/ha, whereas the minimum was estimated to be 212 MgC/ha. The average for the image is approximately 481 MgC/ha, which is within the range one might expect for this relatively productive forest region, with major old-growth remnants remaining.
 
An example of flux grid is shown in Figure 3 for the West Cascades Region for the 2004-2005 period.
 
Figure 3
 
/ODF/indicators/PublishingImages/indicator_g_a_report_600x460_west_cascades_total_flux_2005.jpg
 
The majority of the area appears to be a carbon sink, but a few areas have a very high carbon source value to the atmosphere (<100 MgC/ha/year) associated with recent timber harvest. The average landscape flux for the forest ecosystem was estimated to be -0.808 MgC/ha/year. When the fluxes associated with wood products are also considered the average flux for this landscape was estimated to be -0.381 MgC/ha/year. The lower source was due to the fact that some of the losses from the ecosystem were being stored in wood products. Examining the distribution of sources and sinks, it is clear that cuts from several decades ago are the locations with the highest carbon sink potential, which was as high as 8 Mg C/ha/year (a positive flux).
 
Changes in each of the areas from 1961 to 2008 are indicated in Table 1.
 
Table 1. Average stores and fluxes of all forest-associated carbon for the four test regions examined at the start and end of the monitoring period.
 
RegionTotal Store 1961
Mg C/ha
Total Store 2008
Mg C/ha
Flux 1962-67
Mg C/ha/year
Flux 2004-08
Mg C/ha/year
Klamath315308-0.090.03
West Cascades567529-0.14-0.42
East Cascades357347-0.110.23
Blue Mountains3103100.150.28
 
With the exception of the Blue Mountains, there appears to have been a general decline in carbon stores in the forest sector over this period in all regions. Regardless of the time period, average carbon stores are highest in the West Cascades Region, a result of the generally higher level of productivity. The West Cascades Region appears to be the only region that is still a carbon source by the 2004 to 2008 period, although this is likely to change in the next decade if reduced harvesting continues in that region. The Klamath Region appears to currently be in a carbon balance, whereas the East Cascades and Blue Mountains Regions are likely weak carbon sinks.
 
More detailed information on carbon store and flux for all of the four regions, as well as results that were extrapolated statewide for all of Oregon, are included in the following region-specific sections.
 
One behavior that bears additional analysis is the speed at which the landscape carbon flux can switch from positive to negative and vice versa. We believe this is caused by the fact that very small areas of sources are required to offset very large areas of sinks. This is because on per area basis, sources are much larger than sinks. Therefore a slight change in the area in sources has a very large impact on the average landscape carbon flux.
 

Statewide Carbon Stores and Flux
Carbon Stores
 
The study extrapolated to the state-wide level by averaging the results from the four regions and multiplying by the total area of productive forest land in Oregon (9.56 million ha).  The results of the four regions were weighted by the area they represented of Oregon’s forests. A major region not examined in our analysis was the Coast Range, which was assumed to be similar to the West Cascades region. However, the proportion of private lands is likely higher in the Coast Range and the productivity is higher.
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_oregon_carbon_flux.jpg 
 
The analysis indicates that Oregon’s forest sector currently stores approximately 3,744 Tg (1012).  The trend since 1960 has generally been downward (Figure 6), although there may have been some stabilization in most recent years of both the ecosystem and total forest sector-related carbon stores.

Carbon Flux
 
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_oregon_carbon_flux.jpg 
 
Carbon fluxes for the forest ecosystems and the combined forest sector appears to have been negative most of the 1970 to 2005 period, indicating that the Oregon forest sector has been a net source of carbon to the atmosphere. Since that time, fluxes have been neutral to slightly positive, indicating the system may be switching to a sink from the atmosphere.  Over the 1961-2008 period, the average flux was -3.55 Tg C/year.  That amount is about 20 percent of the value of Oregon’s greenhouse gas emissions which totaled 18 Tg C/year in 2000.  If the fluxes observed in the 2004 to 2008 period continue, then Oregon’s forests are now offsetting about 0.14 Tg C/year, or less than one percent of the state’s greenhouse gas emissions expressed as carbon equivalents.
 
Trend lines are broken at years when satellite imagery was not available.
 

Blue Mountains Region Carbon Stores/Total Mass and Flux
Carbon Stores and Total Mass
 
 
 
 
Carbon stores for the ecosystem and toal forest sector in the Blue Mountains Region have stayed relatively stable over the 1961-2008 period.  Note that, as with other regions, when live stores decline, the dead and wood products stores increase and vice versa.  An exception is the early 2000 period, when fire caused an increase in dead stores, but not wood products stores.
 
Blue Mountains Region - Total Mass (1961 through 2010) [00:01:23; 6.10 MB; MP4]
 
 

Carbon Flux
 
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_blue_mountains_carbon_flux.jpg 
 
Carbon fluxes for the ecosystem and total forest sector in the Blue Mountains Region were generally positive (indicating a sink from the atmosphere) until the early 1980's.  During the 1980 to 2000 period, increased harvests causes a negative flux (indicating a source to the atmosphere).  Since 2001, this landscape apparently has become a carbon sink, despite the net losses from wood products caused by a reduction in timber harvest.
 
Blue Mountains Region - Total Flux (1962 through 2010) [00:01:24; 5.85 MB; MP4]
 
 

East Cascades (includes Cascades crest) Region Carbon Stores/Total Mass and Flux
Carbon Stores and Total Mass
 
 
 
 
Carbon stores for the ecosystem and total forest sector in the East Cascades Region have declined through the mid-1980s.  Since that time, carbon stores for the ecosystem and total forest sector have gradually increased.  Note that, as with other regions, when live stores decline the dead and wood products stores increase and vice versa.
 
East Cascades (and Cascades Crest) Region - Total Mass (1961 through 2010) [00:01:25; 6.43 MB; MP4]
 
 

Total Flux
 
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_east_cascades_carbon_flux.jpg 
 
Carbon fluxes for the ecosystem and total forest sector in the East Cascades Region were generally negative (indicating a source to the atmosphere) until the early 1990s.  Since that time, fluxes have generally been positive (indicating a sink from the atmosphere).  The negative flux in 2002 was associated wtih wildfires.  The negative spike in 1985 appears to be associated with a particularly high annual harvest that year.
 
East Cascades (and Cascades Crest) Region - Total Flux (1962 through 2010) [00:01:31; 6.61 MB; MP4]
 
 

Klamath Region Carbon Stores/Total Mass and Flux
Carbon Stores and Total Mass
 
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_east_cascades_carbon_flux.jpg 
 
Carbon stores for the ecosystem and total forest sector in the Klamath Region have slightly declined through the 1961-2008 period.  Ecosystem carbon stores declined from 1961 to 1990 and seem to have remained relatively constant since then.  Note that, as with other regions, when live stores decline the dead and wood products stores increase and vice versa.
 
Klamath Region - Total Mass (1961 through 2010) [00:01:21; 5.88; MP4]
 
 

Total Flux
 
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_east_cascades_carbon_flux.jpg 
 
Carbon fluxes for the ecosystem and total forest sector in the Klamath Region were generally negative (indicating a source to the atmosphere) until 1995.  Since 1995, it appears that this region has been in carbon balance, with some years negative (a source) and some years positive (a sink).  The negative spike in 1985 appears to be associated with a particularly high annual harvest that year.
 
Klamath Region - Total Flux (1962 through 2010) [00:01:29; 6.42; MP4]
 
 

West Cascades Region Carbon Stores/Total Mass and Flux
Carbon Stores and Total Mass
 
 
/ODF/indicators/images/Indicator_G_a_600x410_West_Cascades_Carbon_Flux.jpg 
 
Carbon stores for the ecosystem and total forest sector in the West Cascades Region have declined through around 2005.  These changes have largely been driven by a decline in the live carbon stores and occurred even when stores in wood productgs were considered.  The carbon stores in dead material, wood products, and stable forms (e.g., mineral soil) increased over this period, but not sufficiently to offset the losses in live carbon.
 
West Cascades Region - Total Mass (1961 through 2010) [00:01:36; 6.62 MB; MP4]
 
 

Flux
 
 
/ODF/indicators/PublishingImages/indicator_g_a_600x410_east_cascades_carbon_flux.jpg 
 
Until recently, carbon fluxes for the ecosystem and total forest sector in the West Cascades Region were generally negative, corresponding to the decrease in carbon stores.  The negative fluxes greatly increased in the 1970s, reaching the highest values in the 1980 to 1990 period.  From 1990 to the current period, the size of the negative flux has gradually declined and this forest may be coming into balance.  Withouot any further disturbances, this area is likely to become a carbon sink during the 2008-2010 period.  However, that is extremely unlikely to happen.
 
West Cascades Region - Total Flux (1962 through 2010) [00:01:11; 5,46 MB; MP4]
 
 

Research and Related Information
Final Report - LandCarb Simulation of Forest Carbon Flux in Oregon; Mark E. Harmon and Frank Schnekenburger, Department of Forest Ecosystems and Society, Oregon State University, December 2009
 
The University of Washington Consortium for Research on Renewable Industrial Materials (CORRIM) analysis: http://www.corrim.org/pubs/reports/2010/swst_vol42/index.asp

Evaluations by the Oregon Roundtable on Sustinable Forests on this indicator
 

Metrics and Data Sources


Metric
Data Source
Status of forest carbon stocks in various carbon pools, including forest products (expressed as mass/area)
 
Status of changes in forest carbon stocks where forests and forest products acting as a source or as a sink (expressed as mass/area/unit of time)
U.S. Forest Service Pacific Northwest Research Station
 
Oregon State University, College of Forestry, Department of Forest Science
 
Oregon Department of Forestry

Related State, National, or International Indicators
  • Montréal Process:  Criterion 5 - Maintenance of forest contribution to global carbon cycles:  2003 Indicator 26: Total forest ecosystem biomass and carbon pool by forest type, age class and successional stage; 2003 Indicator 27: Absorption and release of carbon in standing biomass, woody debris, and soil carbon (contribution to global carbon budget);  2003 Indicator 28: Contribution of forest products to the global carbon budget; 2010 Indicator 22: Total forest ecosystem carbon pools and fluxes; and 2010 Indicator 23: Total forest product carbon pools and fluxes
  • Northeastern Area: Total forest ecosystem biomass and carbon pool (Ecosystem biomass (tons); carbon pool (metric tons)) and Contribution of forest ecosystems to the total carbon budget (Carbon flux)
  • Heinz Center:  Carbon stored in trees, soils, plant litter and wood products (billion metric tons – currently developed for trees only)
  • Oregon Benchmarks: Environment—77: Carbon dioxide emissions as a percent of 1990 emissions; 82: Percent of Oregon’s non-federal forest land in 1974 still preserved for forest use
  • Oregon State of the Environment Report:  The amount of carbon dioxide emitted
  • Mt. Hood National Forest Local Unit Criteria and Indicators Development: Principal 2 – Ecological Integrity: Ecosystem Function: Carbon Sequestration (soil carbon and carbon sinks)