Submitted to: ASA-CSSA-SSSA Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: July 2, 2003
Publication Date: November 2, 2003
Citation: Torbert, H.A., Prior, S.A., and Runion, G.B. 2003. Land use management decisions impact on C sequestration. In Agronomy Abstracts, ASA, Madison, WI [CD-ROM computer file]. Interpretive Summary: This is an abstract.
Technical Abstract: Atmospheric C may be sequestered in soil as a result of taking land out of cultivated agriculture, however, the gains in soil C may be quickly eliminated with the return to cultivation. This study examined the impact of converting land back into cultivated agricultural management on C sequestration within two different soil types. Soil samples from nine depth increments (0-5, 5-10, 10-15, 15-30, 30-45, 45-60, 60-75, 75-90, 90-105 cm) were collected from a Blanton loamy sand (Grossarenic Paleudults) and an Urbo clay loam (Vertic Epiaquepts) in Alabama, that were under forest, permanent pasture, and pasture converted to continuous cultivation for 1 and 2 years. Within the loamy sand soil, continuously cultivated, fallowed for 5 yr, and returned to cultivation after fallowed for 4 yr was included. Soil samples were analyzed for total N, organic C, soil C:N ratio, and soil bulk density. The clay loam soil had a higher capacity to sequester C compared to the loamy sand soil, but little difference was observed between the forest and pasture. In the loamy sand soil, large differences were observed for C between the forested and the permanent pasture. Results indicate that the vulnerability of soil to lose sequestered C may depend on soil type. The clay loam soil, although having higher levels of C, lost much (55%) of its C with 2 yrs of cultivation, while the loamy sand soils showed no significant loss of C content within the same time frame.