1a.Objectives (from AD-416):
This project will investigate changes in rapid, intermediate, and stable soil C and N pools that have occurred over a 10-yr period (2000-2010) as a result of tillage and cropping treatments in Pendleton's long term experiments.
1b.Approach (from AD-416):
Soil samples will be analyzed using USDA-ARS instruments housed in the chemistry laboratory of the Columbia Plateau Conservation Research Center.
In cooperation with Oregon State University, we completed analysis of approximately 4,700 soil samples for pH using standard procedures over a calibration range of 4.0 to 10.0. In addition, these samples were analyzed for total carbon and total nitrogen using dry combustion analysis. These data with 2010 year soil properties were delivered to project investigators for inclusion into a long-term database and public use. This research supported objective 3C of the parent project by providing ARS and OSU scientists with information that can be used to compute the amount of biomass required to maintain soil organic carbon under the winter wheat-summer fallow rotation.