A regionally-adapted implementation of conservation agriculture delivers rapid improvements to soil properties associated with crop yield stability

Abstract

Climate models predict increasing weather variability, with negative consequences for crop production. Conservation agriculture (CA) may enhance climate resilience by generating certain soil improvements. However, the rate at which these improvements accrue is unclear, and some evidence suggests CA can lower yields relative to conventional systems unless all three CA elements are implemented: reduced tillage, sustained soil cover, and crop rotational diversity. These cost-benefit issues are important considerations for potential adopters of CA. Given that CA can be implemented across a wide variety of regions and cropping systems, more detailed and mechanistic understanding is required on whether and how regionally-adapted CA can improve soil properties while minimizing potential negative crop yield impacts. Across four US states, we assessed short-term impacts of regionally-adapted CA systems on soil properties and explored linkages with maize and soybean yield stability. Structural equation modeling revealed increases in soil organic matter generated by cover cropping increased soil cation exchange capacity, which improved soybean yield stability. Cover cropping also enhanced maize minimum yield potential. Our results demonstrate individual CA elements can deliver rapid improvements in soil properties associated with crop yield stability, suggesting that regionally-adapted CA may play an important role in developing high-yielding, climate-resilient agricultural systems.

Temporal variability of soil organic carbon in paddies during 13‐year conservation tillage

“…With the quest to pursue additional research on soil C sink capacity and assess the SOC dynamics, this study presented the data on temporal variability of SOC by using CV for the later stage of the experiment (2007–2017). Previous studies using CV under conservation tillage were mainly focused on the stability of crop yield (Williams et al, ) and soil hydrological properties (Schwen, Bodner, Scholl, Buchan, & Loiskandl, ). Thus far, using CV of SOC among tillage practices is still poorly understood, and there are no previous studies to compare with the present study.…”

“…With the quest to pursue additional research on soil C sink capacity and assess the SOC dynamics, this study presented the data on temporal variability of SOC by using CV for the later stage of the experiment (2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016)(2017). Previous studies using CV under conservation tillage were mainly focused on the stability of crop yield (Williams et al, 2018) and soil hydrological properties (Schwen, Bodner, Scholl, Buchan, & Loiskandl, 2011 Furthermore, soil C accumulation is a slow process, and this study was conducted over a period of 13 years. Therefore, the higher SOC sequestration at the 0-30 cm depth under NTS can be achieved only after long-term management (Melero, López-Garrido, Murillo, & Moreno, 2009 C increment was higher under NTS compared with other tillage practices, indicating that a higher fraction of C from crop residues was converted into SOC under NTS than in other treatments, which might contribute to its low SOC variability.…”

The Ability of Conservation Agriculture to Conserve Soil Organic Carbon and the Subsequent Impact on Soil Physical, Chemical, and Biological Properties and Yield

“…Where legumes are included, these can also add additional N to the system, which can enhance soil fertility and subsequent crop biomass production (Hansen et al, 2012;Mbuthia et al, 2015;Raphael et al, 2016;Veloso et al, 2018). The maintenance of residue cover can also decrease processes that can limit the growth and biomass production of the main crop, such as erosion, nutrient leaching, and weeds, pests and diseases Gabriel et al, 2013;Veloso et al, 2018;Williams et al, 2018).…”

Cyclic Yield Stability of Ley Farming System in Northern Quebec

“…The yearly effect of tillage practice on forage yield disappeared in a cyclic assessment regardless of cycle initialization. While MP may increase crop performance but decrease soil quality in the long run (Karlen et al, 2013a), combining regionally adapted soil conservation measures to improve soil quality rapidly (<5 yr) and to mitigate the effect of climate change on crop productivity may include reduced tillage, sustained soil cover, and crop rotational diversity (Williams et al, 2018). In northern Quebec agriculture, CP showed negligible effects on forage crops compared to MP in a 3‐yr ley farming system.…”

“…In long‐term experiments, yield stability is generally assessed from yearly data to compute the coefficient of variation as stability index (Gaudin et al, 2015; Lafond et al, 2017; Nielsen and Vigil, 2018; Williams et al, 2018). The coefficient of variation based on yearly data can be reduced by approximately if computed across crop cycles of period n where management options such as storage and land reallocation to crop phases are available.…”