|Mausbach, Maurice - USDA-NRCS-WASHINGTON DC|
|Goebel, Jeffrey - USDA-NRCS, WASHINGTON DC|
|Allan, Deborah - UNIVERSITY OF MN|
Submitted to: Soil Science Society of America Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 21, 2000
Publication Date: N/A
Interpretive Summary: To assist Congress in developing and evaluating conservation programs and policies to promote practices that increases soil organic carbon (SOC) levels on private lands in the US, a statistically valid and efficient method is need for monitoring SOC at the field, region, and national scales. The National Resource Inventory (NRI) conducted by the USDA- Natural Resources Conservation Service (NRCS) may provide such monitoring tool, but it has never been evaluated for its potential to monitor SOC levels. The purpose of this research was to evaluate use of the NRI to estimate SOC levels in four different regions of the country. Significant differences in SOC levels under different land-use practices could be detected in each region. The precision with which SOC levels could be estimated ranged from 0.5 to 5.0 Mg ha-1 with greater precision in areas with lower SOC levels. Results indicated that the NRI may be used for evaluating the effects of different land-use practices on SOC levels at a regional scale. Repeated sampling of the same NRI points over time would allow NRCS to estimate the amount of carbon sequestered in or lost from the soil with changes in land-use at a regional scale. The development and adoption of conservation programs in combination with regional and national NRI assessments to evaluate the effectiveness of these programs could help improve the quality and productivity of the nation's soils and help sequester carbon, potentially reducing atmospheric CO2 concentrations.