Authors: S. Senthilkumar, B. Basso, A. N. Kravchenko, G. P. Robertson
First published: November 1, 2009
Abstract
Temporal changes in soil carbon (C) content vary as a result of complex interactions among different factors including climate, baseline soil C levels, soil texture, and agricultural management practices.
The study objectives were:
The data were collected from two long-term experiments established in 1986 and 1988. Georeferenced samples were collected from both experiments before establishment and then were resampled in 2006 and 2007. The studied agricultural treatments included the conventional chisel-plow and no-till management systems with and without N fertilization and the organic chisel-plow management with cover crops. Total C was either lost in the conventional chisel-plowed systems or was only maintained at the 1980s levels by the conservation management systems. The largest loss in the agricultural treatments was 4.5 Mg ha−1 total C observed in the chisel-plow system without N fertilization. A loss of 17.3 Mg ha−1 occurred in the virgin grassland soil. Changes in C content tended to be negatively related to baseline C levels. Under no-till, changes in C were positively related to silt + clay contents.
The SALUS predictions of soil C changes were in excellent agreement with the observed data for most of the agricultural treatments and for the virgin soil.
Academic Citation