International workshop on

  
Koli (c) Metla/Erkki Oksanen

Development of Models and Forest Soil Surveys for Monitoring of Soil Carbon

April 5-8, 2006 at Koli, Finland
 >

Methodologies for estimating forest soil carbon stocks using annual forest inventory data

C.H. Perry

USDA Forest Service, North Central Research Station, St. Paul, MN 55108; ph. 651-649-5191;
fax 651-649-5140; e-mail: charleshperry@fs.fed.us

The USDA Forest Service Forest Inventory and Analysis (FIA) program performs an annual forest inventory that includes measurements of down woody material and soil quality. These measurements are taken on a systematic nation-wide grid of approximately 125,000 plots where each one may represent up to 38,850 ha of forest. Between ten to twenty percent of these plots are measured every year. I combined tree, down woody material, and soil measurements collected over three years (2001 - 2003) to evaluate current methodologies for estimating the contribution of soil carbon to total carbon storage in forests of the United States. Tree measurements include species, height, and diameter at breast height. Carbon content of live tree biomass is estimated with carbon conversion constants. Down woody material carbon stocks (coarse and fine woody debris) are estimated using line intercept transects and carbon conversion constants. The soil quality indicator includes volumetric sampling of the forest floor and the collection of mineral soil cores representing depth increments of 0 – 10 cm and 10 – 20 cm. Carbon content of the soil samples is determined by dry combustion. Carbon storage by pool is roughly ranked as follows: standing tree biomass > 0 – 10 cm mineral soil > 10 – 20 cm mineral soil > coarse woody debris > the forest floor ≈ fine woody debris. The tree measurements actually occur on a denser sampling network than either the down woody material or soil measurements. Additional research is underway to determine effective geospatial modeling techniques for estimating the soil carbon at all tree measurement locations.

 
   Päivitetty:   02.03.2006 / EKel Metla : Events   Palaute Metlan etusivulle
. .