Soil organic carbon stock change following perennialization: a meta-analysis

Abstract

Perennial crops replacing annual crops are drawing global attention because they harbor potential for sustainable biomass production and climate change mitigation through soil carbon sequestration. At present, it remains unclear how long perennial crops can sequester carbon in the soil and how soil carbon stock dynamics are influenced by climate, soil, and plant properties across the globe. This study presents a meta-analysis synthesizing 51 publications (351 observations at 77 sites) distributed over different pedo-climatic conditions to scrutinize the effect of perennialization on organic carbon accumulation in soil compared with two annual benchmark systems (i.e., monoculture and crop rotation). Results showed that perennial crops significantly increased soil organic carbon stock by 16.6% and 23.1% at 0–30 cm depth compared with monoculture and crop rotation, respectively. Shortly after establishment (< 5 years), perennial crops revealed a negative impact on soil organic carbon stock; however, long duration (> 10 years) of perennialization had a significant positive effect on soil organic carbon stock by 30% and 36.4% at 0–30 cm depth compared with monoculture and crop rotation, respectively. Compared with both annual systems, perennial crops significantly increased soil organic carbon stock regardless of their functional photosynthetic types (C3, C4, or C3-C4 intermediates) and vegetation type (woody or herbaceous). Among other factors, pH had a significant impact on soil organic carbon; however, the effect of soil textures showed no significant impact, possibly due to a lack of observations from each textural class and mixed pedoclimatic effects. Results also showed that time effect of perennialization revealed a sigmoidal increase of soil organic carbon stock until about 20 years; thereafter, the soil carbon stocks advanced towards a steady-state level. In conclusion, perennial crops increased soil organic carbon stock compared with annual systems; however, the time since conversion from annual to perennial system decisively impacted soil organic carbon stock changes.

Short‐term effects of Kernza and alfalfa on microbial communities

“…A recent meta‐analysis by Siddique et al. (2023) further underscored that short‐term changes following such conversions are often a decline rather than an increment, suggesting it could take up to 5 years with the perennials to see the benefits over the previous annual crops in terms of the soil carbon storage. However, such impacts may be limited to only the surface layer (0–5 cm depth).…”

“…A previous global assessment of SOC changes after the conversion of annual crops to perennial crops by Ledo et al (2020) also revealed the possibility of a temporary decline in SOC content. A recent meta-analysis by Siddique et al (2023) further underscored that short-term changes following such conversions are often a decline rather than an increment, suggesting it could take up to 5 years with the perennials to see the benefits over the previous annual crops in terms of the soil carbon storage. However, such impacts may be limited to only the surface layer (0-5 cm depth).…”

Early impacts of marginal land‐use transition toMiscanthuson soil quality and soil carbon storage across Europe

“…However, in sites previously managed as grassland, this mechanism of C compensation requires more time to occur. According to the meta-analysis of Siddique et al (2023), the change of SOC stock under perennial crops follows a sigmoidal curve over time. The increase in SOC with perennial crops like Miscanthus started after approximately 5 years, compensating for losses of original SOC caused by soil disturbance, soil priming and lower productivity of newly established crops.…”

Effects of Different Management Measures on Carbon Stocks and Soil Carbon Stocks in Moso Bamboo Forests: Meta-Analysis and Control Experiment

“…The results derived from the study indicated that heavy logging led to increased soil N 2 O emissions [30]. And in 2023, Siddique et al [31] employed meta-analysis methods to examine the effect of perennialization on organic carbon accumulation in soil. Their research findings indicate that the duration since conversion from an annual to a perennial system significantly increased soil organic carbon stock by 16.6% and 23.1% at depths of 0-30 cm compared with monoculture and crop rotation, respectively.…”