Conventional and Zero Tillage with Residue Management in Rice–Wheat System in the Indo-Gangetic Plains: Impact on Thermal Sensitivity of Soil Organic Carbon Respiration and Enzyme Activity

Abstract

The impact of global warming on soil carbon (C) mineralization from bulk and aggregated soil in conservation agriculture (CA) is noteworthy to predict the future of C cycle. Therefore, sensitivity of soil C mineralization to temperature was studied from 18 years of a CA experiment under rice–wheat cropping system in the Indo-Gangetic Plains (IGP). The experiment comprised of three tillage systems: zero tillage (ZT), conventional tillage (CT), and strip tillage (ST), each with three levels of residue management: residue removal (NR), residue burning (RB), and residue retention (R). Cumulative carbon mineralization (Ct) in the 0–5 cm soil depth was significantly higher in CT with added residues (CT-R) and ZT with added residues (ZT-R) compared with the CT without residues (CT-NR). It resulted in higher CO2 evolution in CT-R and ZT-R. The plots, having crop residue in both CT and ZT system, had higher (p < 0.05) Van’t-Hoff factor (Q10) and activation energy (Ea) than the residue burning. Notably, micro-aggregates had significantly higher Ea than bulk soil (~14%) and macro-aggregates (~40%). Aggregate-associated C content was higher in ZT compared with CT (p < 0.05). Conventional tillage with residue burning had a reduced glomalin content and β-D-glucosidase activity than that of ZT-R. The ZT-R improved the aggregate-associated C that could sustain the soil biological diversity in the long-run possibly due to higher physical, chemical, and matrix-mediated protection of SOC. Thus, it is advisable to maintain the crop residues on the soil surface in ZT condition (~CA) to cut back on valuable C from soils under IGP and similar agro-ecologies.

Balancing Non‐CO2 GHG Emissions and Soil Carbon Change in U.S. Rice Paddies: A Retrospective Meta‐Analysis and Agricultural Modeling Study

“…Our factorial analysis revealed that enhanced tillage practices significantly contributed to an increase in soil CO 2 release by 6.1%, a finding consistent with other studies conducted in the U.S. (Bai et al., 2019; Dutta et al., 2023). This effect can likely be attributed to the fact that tillage disrupts the soil, accelerating the rate of decomposition of soil organic matter (Bai et al., 2019; Mishra et al., 2010; Olson et al., 2014; Salinas‐Garcia et al., 1997) and diminishing the biomass of fungi and earthworms (Briones & Schmidt, 2017; Lavelle et al., 1999).…”

“…Numerous field investigations and meta‐analyses have provided evidence that intensified agricultural management practices significantly exacerbate soil GHG emissions in croplands (Bai et al., 2019; Bo et al., 2022; Cui et al., 2013; Davidson, 2009; Dutta et al., 2023; Gupta et al., 2021; Lu et al., 2021; Reay et al., 2012). However, these practices also hold the potential to confer advantages for SOC change in croplands due to their substantial mitigation benefits, cost‐effectiveness, and additional positive outcomes such as improved soil and water quality and preservation of biodiversity (Fargione et al., 2018; Li et al., 2022).…”

Balancing non-CO2 GHG emissions and soil carbon sequestration in U.S. rice paddies: implications for natural climate solutions

“…Our factorial analysis revealed that enhanced tillage practices significantly contributed to an increase in soil CO 2 release by 6.1%, a finding consistent with other studies conducted in the U.S. (Bai et al, 2019;Dutta et al, 2023). This effect can likely be attributed to the fact that tillage disrupts the soil, accelerating the rate of decomposition of soil organic matter (Mishra et Furthermore, the disturbance caused by tillage introduces more oxygen into the soil, temporarily altering the anaerobic environment.…”

“…Numerous field investigations and meta-analyses have provided evidence that intensified agricultural management practices significantly exacerbate soil GHG emissions in croplands (Cui et al, 2013;Reay et al, 2012;Lu et al, 2021;Davidson et al, 2009;Bai et al, 2019;Dutta et al, 2023;Bo et al, 2022;Gupta et al, 2021). However, these practices also hold the potential to confer advantages for SOC sequestration in croplands due to their substantial mitigation benefits, cost-effectiveness, and additional positive outcomes such as improved soil and water quality and preservation of biodiversity (Fargione et al, 2018;.…”

Impact of Chemically Diverse Organic Residue Amendment on Soil Enzymatic Activities in a Sandy Loam Soil

“…Presently, limited information is available in the literature on the role of crop residue heterogeneity on the dynamics of different enzymatic activities in soil. However, studies have investigated the effects of organic residue amendments on soil enzymatic activities, but most of these studies have focused on specific residue types or narrowly defined chemical compositions [37,38]. To fully comprehend the influence of organic residues on soil enzymatic activities, it is crucial to consider the diverse range of residues commonly available in agricultural systems.…”