Estimating the Global Influence of Cover Crops on Ecosystem Service Indicators in Croplands With the LPJ-GUESS Model

Summary, in English

Cover crops (CCs) can improve soil nutrient retention and crop production while providing climate change mitigation co-benefits. However, quantifying these ecosystem services across global agricultural lands remains inadequate. Here, we assess how the use of herbaceous CCs with and without biological nitrogen (N) fixation affects agricultural soil carbon stocks, N leaching, and crop yields, using the dynamic global vegetation model LPJ-GUESS. The model performance is evaluated with observations from worldwide field trials and modeled output further compared against previously published large-scale estimates. LPJ-GUESS broadly captures the enhanced soil carbon, reduced N leaching, and yield changes that are observed in the field. Globally, we found that combining N-fixing CCs with no-tillage technique could potentially increase soil carbon levels by 7% (+0.32 Pg C yr⁻¹ in global croplands) while reducing N leaching loss by 41% (−7.3 Tg N yr⁻¹) compared with fallow controls after 36 years of simulation since 2015. This integrated practice is accompanied by a 2% of increase in total crop production (+37 million tonnes yr⁻¹ including wheat, maize, rice, and soybean) in the last decade of the simulation. The identified effects of CCs on crop productivity vary widely among main crop types and N fertilizer applications, with small yield changes found in soybean systems and highly fertilized agricultural soils. Our results demonstrate the possibility of conservation agriculture when targeting long-term environmental sustainability without compromising crop production in global croplands.

• Författare: Jianyong Ma; Peter Anthoni; Stefan Olin; Sam S. Rabin; Anita D. Bayer; Longlong Xia; Almut Arneth
• Avdelning/ar: eSSENCE: The e-Science Collaboration; Institutionen för naturgeografi och ekosystemvetenskap; BECC: Biodiversity and Ecosystem services in a Changing Climate; MERGE: ModElling the Regional and Global Earth system
• Publiceringsår: 2023-05
• Språk: Engelska
• Publikation/Tidskrift/Serie: Earth's Future
• Volym: 11
• Issue: 5
• Länkar: http://dx.doi.org/10.1029/2022EF003142
• Dokumenttyp: Artikel i tidskrift
• Förlag: John Wiley & Sons Inc.
• Ämne: Environmental Sciences related to Agriculture and Land-use
• Nyckelord: conservation agriculture; cover crops; crop yields; dynamic vegetation model; nitrogen leaching; soil carbon sequestration
• Status: Published
• ISBN/ISSN/Övrigt: ISSN: 2328-4277