Full inversion tillage during pasture renewal to increase soil carbon storage : New Zealand as a case study

© 2021 John Wiley & Sons Ltd.

Bibliographische Detailangaben
Veröffentlicht in:Global change biology. - 1999. - 27(2021), 10 vom: 17. Mai, Seite 1998-2010
1. Verfasser: Lawrence-Smith, Erin J (VerfasserIn)
Weitere Verfasser: Curtin, Denis, Beare, Mike H, McNally, Sam R, Kelliher, Frank M, Calvelo Pereira, Roberto, Hedley, Mike J
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:Global change biology
Schlagworte:Journal Article deep soil carbon full inversion tillage grassland renovation negative emission practice offset greenhouse gas emissions pasture renewal soil carbon sequestration Soil Carbon 7440-44-0
Beschreibung
Zusammenfassung:© 2021 John Wiley & Sons Ltd.
As soils under permanent pasture and grasslands have large topsoil carbon (C) stocks, the scope to sequester additional C may be limited. However, because C in pasture/grassland soils declines with depth, there may be potential to sequester additional C in the subsoil. Data from 247 continuous pasture sites in New Zealand (representing five major soil Orders and ~80% of the grassland area) showed that, on average, the 0.15-0.30 m layer contained 25-34 t ha-1 less C than the top 0.15 m. High-production grazed pastures require periodic renewal (re-seeding) every 7-14 years to maintain productivity. Our objective was to assess whether a one-time pasture renewal, involving full inversion tillage (FIT) to a depth of 0.30 m, has potential to increase C storage by burying C-rich topsoil and bringing low-C subsoil to the surface where C inputs from pasture production are greatest. Data from the 247 pasture sites were used to model changes in C stocks following FIT pasture renewal by predicting (1) the C accumulation in the new 0-0.15 m layer and (2) the decomposition of buried-C in the new 0.15-0.30 m layer. In the 20 years following FIT pasture renewal, soil C was predicted to increase by an average of 7.3-10.3 (Sedimentary soils) and 9.6-12.7 t C ha-1 (Allophanic soils), depending on the assumptions applied. Adoption of FIT for pasture renewal across all suitable soils (2.0-2.6 M ha) in New Zealand was predicted to sequester ~20-36 Mt C, sufficient to offset 9.6-17.5% of the country's cumulative greenhouse gas emissions from agriculture over 20 years at the current rate of emissions. Given that grasslands account for ~70% of global agricultural land, FIT renewal of pastures or grassland could offer a significant opportunity to sequester soil C and offset greenhouse gas emissions
Beschreibung:Date Completed 23.04.2021
Date Revised 23.04.2021
published: Print-Electronic
Citation Status MEDLINE
ISSN:1365-2486
DOI:10.1111/gcb.15561