Location: Agroecosystems Management Research
Project Number: 5030-12210-003-57-I
Project Type: Interagency Reimbursable Agreement
Start Date: Dec 1, 2014
End Date: Dec 31, 2018
1) Use the chronosequence of reconstructed prairies to define the relationship between prairie age and soil C content; 2) Use the relationship between prairie age and soil C to calculate the rate of soil C change in reconstructed prairie soil at Neal Smith National Wildlife Refuge (NSNWR); 3) Apply conceptual and data collection frameworks developed at NSNWR as a basis for quantifying C change for other locations and spatial scales; and 4) Use data to ground-truth and verify USGS modeled estimates of soil C stocks.
Reconstructing former cropland to tallgrass prairie ecosystems can increase soil organic carbon (SOC) and enhance C sequestration to mitigate increases in atmospheric CO2. Quantifying the rate of C change in reconstructed prairies will increase our understanding of C cycling in former cropland soil. This research project will collect, compile, and analyze data for terrestrial carbon stocks in reconstructed tallgrass prairie ecosystems in the U.S. Midwest. The work will be conducted at the Neal Smith National Wildlife Refuge (NSNWR), the largest tallgrass prairie reconstruction site in the United States, located in Jasper County, south-central Iowa. The chronosequence of prairie reconstructions provides a natural laboratory for assessing soil C change after conversion of former cropland to tallgrass prairie. USDA-ARS devised an experimental framework to capture data from across the refuge that allowed repeated sampling at the same sites across years and minimized variability due to soil type differences. Data collected in 2000, 2005, and 2010 by USDA-ARS-NLAE from a total of 20 reconstructed prairies ranging in age from 1 to 17 years and 5 cropped sites planted to a corn (Zea mays L.) and soybean (Glycine max L. Merr.) will be used in this study. USGS is leading a national assessment of carbon sequestration and greenhouse gas (GHG) fluxes in and out of ecosystems. The overall objective is to conduct a nationwide assessment, as well as continued monitoring, focusing on ecological carbon storage and GHG fluxes under the present conditions and future scenarios, as determined by key natural and anthropogenic processes including climate change, wildfire, and land management. This project will link USDA-ARS research efforts at NSNWR with the national monitoring and modeling efforts of the USGS to quantity soil C change.