Long-Term No-Tillage Sequesters Soil Organic Carbon in Cool Semiarid Regions

Abstract

No‐tillage (NT) has been promoted as a strategy for sequestering soil organic carbon (SOC) in crop production systems. However, recent research suggests stratification rather than sequestration of SOC may occur following adoption of NT, with no net increase in SOC. Our objective was to determine if SOC was sequestered in long‐term NT plots in a cool semiarid region. Soil was collected from 0‐ to 30‐, 30‐ to 60‐, and 60‐ to 90‐cm depth intervals in plots arranged in a randomized complete block where clean‐tillage (CT), reduced‐tillage (RT), and NT treatments had been maintained in eight blocks for 20 yr at Dickinson, ND, USA. More SOC occurred at the 0‐ to 30‐cm depth under NT (64 Mg C ha–1) than under both RT and CT (≤55 Mg C ha–1) management (SE = 2; P < 0.001) and at the 30‐ to 60‐cm depth under NT than RT (33 vs. 28 Mg C ha–1, P < 0.03). Similarly, more SOC occurred at the 60‐ to 90‐cm depth under NT than RT (29 vs. 22 Mg C ha–1, P = 0.003). Overall, amounts of SOC in the upper 90 cm of soil were greatest under NT at 127 Mg C ha–1 compared with 104 Mg C ha–1 under RT and 112 Mg C ha–1 under CT (P = 0.005). Results of this research indicate that conversion of CT and RT to NT in cool semiarid regions can result in the sequestration of SOC when both surface and subsurface depths are considered.

The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards

“…Soil loss is enhanced in cropped soils due to soil management and tillage practices (Blavet et al, 2009;Boardman et al, 1990;Boix-Fayos et al, 2005;Cerdan et al, 2010;Gómez et al, 1999;Vanwalleghem et al, 2011). Indeed, this is due to several reasons such as conventional plowing, removal of the original vegetation, use of pesticides and herbicides that damage biological activity in soils (Freemark and Boutin, 1995;Johnsen et al, 2001;Pelosi et al, 2013), low overall vegetation cover, soil compaction and sealing due to machinery traffic, depletion of organic matter and absence of soil erosion control measures (Arnáez et al, 2015;Bakker et al, 2005;Carr et al, 2015;Cerdà et al, 2009;Ciampalini et al, 2012;Cots-Folc et al, 2009;Laudicina et al, 2015;Raclot et al, 2009;Tarolli et al, 2014Tarolli et al, , 2015. The effect of intensive agricultural practices on soil erosion is now well known and is concerning given evidence that civilizations have collapsed throughout human history due to erosion (Brevik and Hartemink, 2010) and that erosion continues to negatively affect civilizations in all regions of the world (Brevik, 2009a;Brevik et al, 2015;Cerdà and Doerr, 2007;O'hara et al, 1993;Pimentel et al, 1987;Shi and Shao, 2000;Smith et al, 2015).…”

Long‐Term Durum Wheat‐Based Cropping Systems Result in the Rapid Saturation of Soil Carbon in the Mediterranean Semi‐arid Environment

“…(Cely et al, 2014;Parras-Alcántara & Lozano-García, 2014;Srinivasarao et al, 2014;Weyers & Spokas, 2014;Kaleeem Abbasi et al, 2015). The SOC pool can generally be increased by agricultural management that increases litter input and reduces tillage intensity (Bell et al, 2003;Alvaro-Fuentes et al, 2009a;Carr et al, 2015). With respect to the size of the SOC pool, the quantity and quality of crop residues are especially important.…”

Selected highlights in American soil science history from the 1980s to the mid-2010s

“…In recent years this methodology has come into question, with indications that no-till may concentrate carbon accumulations in upper soil layers with reductions of soil carbon at depth, giving no net difference in carbon versus clean-till techniques when the entire soil profile is considered (Baker et al, 2007;Blanco-Canqui and Lal, 2008;Christopher et al, 2009). That being said, results have been mixed, with some studies indicating that no-till does lead to higher soil carbon content than clean-till even when sampling is done to depths of about 1 m or deeper (Omonode et al, 2006;Varvel and Wilhelm, 2011;Carr et al, 2015). It now appears that whether or not no-till sequesters soil carbon at depths greater than 20-30 cm may depend on climate (VandenBygaart et al, 2003).…”