Preprints
https://doi.org/10.5194/bg-2022-6
https://doi.org/10.5194/bg-2022-6
 
07 Feb 2022
07 Feb 2022
Status: this discussion paper is a preprint. It has been under review for the journal Biogeosciences (BG). The manuscript was not accepted for further review after discussion.

Assessing the effects of no-till on SOC dynamics throughout the soil profile after grassland renovation and conversion to silage maize

Josue De Los Rios1, Arne Poyda1, Thorsten Reinsch1, Christof Kluß1, Ralf Loges1, and Friedhelm Taube1,2 Josue De Los Rios et al.
  • 1Institute of Crop Sciences and Plant Breeding, Grass and Forage Sciences/Organic Agriculture, Christian-Albrechts-University, Kiel, Germany
  • 2Grass-based Dairy Systems, Animal Production Systems Group, Wageningen University (WUR), Wageningen, Netherlands

Abstract. Land-use change (LUC) and conventional tillage (CT) result in the reduction of the high soil organic carbon (SOC) stocks stored in grassland ecosystems during their conversion and renovation, contributing to global warming. While plenty studies show the use of no-tillage (NT) as a promising option to increase the topsoil SOC stocks of arable lands, its potential to conserve SOC during grassland conversion and renovation events has been poorly investigated. Further, the effects of LUC and tillage methods on the SOC dynamics have been limited to the topsoil by most studies, thus overlooking their impact on the subsoil where significant amounts of SOC are stored, and changes in vegetation and residue distribution can negatively affect these. In this study, a 10-year-old grassland was converted to continuous silage maize (CM) using NT (NT-CM) and CT (CT-CM), and renovated using NT (NT-GR), while some part remained undisturbed as a control (GC). The systems were either non-fertilized (N0) or fertilized according to a demand of 180 and 380 kg N ha−1 yr−1 (N1) in the silage maize and grassland systems, respectively. SOC stocks were measured annually and annual SOC changes (ΔSOC, in Mg C ha−1 yr−1) were calculated for different soil layers (0–30, 30–60 and 60–90 cm) and across the whole profile (0–90 cm) over a 6-year period (2014–2020). Annual soil carbon inputs (Ci) via plant residues were quantified and related to ΔSOC. Results showed that cropping systems significantly affected SOC dynamics over time. At 0–30 cm, SOC stocks were significantly reduced after conversion using both tillage methods, however, 44 % lower annual losses were obtained in NT-CM (−1.5 Mg C ha−1 yr−1) compared to CT-CM (−2.7 Mg C ha−1 yr−1). Conversely, SOC stocks remained unchanged after NT-GR same as the GC. In the subsoil, SOC stocks increased under GC (1.1 Mg C ha−1 yr−1) and remained unchanged in the other systems. Across the whole profile, SOC stocks increased in GC, remained stable in NT-GR, and decreased in NT-CM and CT-CM with mean annual change rates of 1.3, −0.1, −1.9 and −3.4 Mg C ha−1 yr−1, respectively. The differences in ΔSOC between the unploughed systems (NT-GR, NT-CM and GC) were strongly related to the annual soil Ci from plant residues in the topsoil. Our findings highlight the great potential of NT to slow down the annual SOC losses after grassland conversion or renovation, and that C sequestration can occur in the subsoil of permanent grasslands when the topsoil C is already saturated. This strengthens the need to consider the SOC changes occurring in the whole profile after a LUC event.

Josue De Los Rios et al.

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on bg-2022-6', Anonymous Referee #1, 14 Feb 2022
    • AC1: 'Reply on RC1', Josue De Los Rios, 23 Mar 2022
    • AC2: 'Reply on RC1', Josue De Los Rios, 23 Mar 2022
  • RC2: 'Comment on bg-2022-6', Anonymous Referee #2, 13 Mar 2022
    • AC4: 'Reply on RC2', Josue De Los Rios, 23 Mar 2022
  • AC3: 'Comment on bg-2022-6', Josue De Los Rios, 23 Mar 2022

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on bg-2022-6', Anonymous Referee #1, 14 Feb 2022
    • AC1: 'Reply on RC1', Josue De Los Rios, 23 Mar 2022
    • AC2: 'Reply on RC1', Josue De Los Rios, 23 Mar 2022
  • RC2: 'Comment on bg-2022-6', Anonymous Referee #2, 13 Mar 2022
    • AC4: 'Reply on RC2', Josue De Los Rios, 23 Mar 2022
  • AC3: 'Comment on bg-2022-6', Josue De Los Rios, 23 Mar 2022

Josue De Los Rios et al.

Josue De Los Rios et al.

Viewed

Total article views: 359 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
281 64 14 359 25 6 8
  • HTML: 281
  • PDF: 64
  • XML: 14
  • Total: 359
  • Supplement: 25
  • BibTeX: 6
  • EndNote: 8
Views and downloads (calculated since 07 Feb 2022)
Cumulative views and downloads (calculated since 07 Feb 2022)

Viewed (geographical distribution)

Total article views: 329 (including HTML, PDF, and XML) Thereof 329 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 26 May 2022
Download
Short summary
Land use change (LUC) and conventional tillage (CT) are resulting in the reduction of the high soil organic carbon (SOC) stocks stored in grassland ecosystems during their conversion and renovation, contributing thus to global warming. Using no-tillage (NT) is seen as an avenue to minimize or even conserve SOC stocks during these events. Our results show that SOC losses are greatly reduced after grassland conversion to arable land, whereas during renovation it contributes to conserve them.
Altmetrics