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The continuous rice–wheat cropping system in South Asia has caused irreversible environmental damage, raising concerns about the long-term sustainability of the region's agricultural systems. To address this issue, farm experiments were conducted for two successive years (2019–20 and 2020–21) to assess the impact of different cropping systems under conservation agriculture (CA) practices on the yield, productivity, and profitability of wheat. Results showed that the highest grain yield of wheat was observed in scenarios Sc6, Sc4, and Sc2, which involved full CA permanent-bed soybean (PB)–permanent-bed wheat (PB)–permanent-bed summer moong (PB), full CA permanent-bed maize (PB)–permanent-bed wheat (PB)–permanent-bed summer moong (PB), and partial CA puddled transplanted rice–Happy Seeder wheat–zero-till summer moong (ZT). Additionally, the highest irrigation water productivity (IWP), wheat grain macronutrient uptake, net return, and benefit–cost ratio (B:C ratio) were recorded under Sc6, full CA permanent-bed soybean (PB)–permanent-bed wheat (PB)–permanent-bed summer moong (PB) compared to farmers' practice puddled transplanted rice (PTR)–conventional-till wheat–summer moong (Sc1) during both years. The system productivity also increased in scenarios Sc2, Sc4, and Sc6 (by 9.72%, 9.65%, and 14.14% in the first year and 10.68%, 14.14%, and 15.55% in the second year) compared to Sc1—farmers' practice puddled transplanted rice (PTR)–conventional-till wheat–summer moong, Sc3—farmers' practice fresh-bed maize (FB)–conventional-till wheat–summer moong, and Sc5–farmers' practice fresh-bed soybean (FB)–conventional-till wheat (CT)–summer moong. The findings suggest that the conservation agriculture soybean–wheat–summer moong (Sc6) on permanent-bed cropping systems with inclusion legumes can be a potential option to enhance yield attributes, productivity, and profitability, as well as the sustainability of natural resources in the region while decreasing environmental footprints. [ABSTRACT FROM AUTHOR]

The improvement of soil quality in agro-ecosystems is one of the major objectives of conservation agriculture (CA) strategies. The objective of this study was to evaluate, quantify and compare the effects of two tillage practices, four crop rotation sequences, two residue management systems and their interactions on the soil quality of a Haplic Plinthosol in South Africa using the Soil Management Assessment Framework (SMAF). The evaluation was done on a CA field trial established in 2012 in the Eastern Cape Province of South Africa. The trial was laid out in a split-split-plot design with tillage: conventional tillage (CT) and no-till (NT) as main plot treatments. Sub-treatments were crop rotations: maize-fallow-maize (MFM); maize-fallow-soybean (MFS); maize-wheat-maize (MWM); maize-wheat-soybean (MWS). Residue management treatments: removal (R -) and retention (R +) were in the sub-sub plots. Soils from the CA trial were sampled at 0 – 5 and 5 – 10 cm depths after five cropping seasons (2012–2015). Thirteen soil quality indicators were determined to assess soil quality. The SMAF soil quality index (SMAF-SQI) was used as an indicator of overall soil quality. The study results demonstrated the dominance of tillage practices in significantly affecting soil biological, chemical and physical properties in the short term than crop rotation sequences and residue management systems. The soil biological indicators viz. SOC, MBC and BG activity were more sensitive to CA strategies, which confirmed their effectiveness as tools for soil quality assessments in the short-term. The study also revealed the short-term significant effects of tillage on the overall SMAF-SQI while crop rotation and residue management had no significant effects. Overall soil quality assessment using the SMAF technique provided a sound basis for distinguishing the short-term impacts of CA strategies on the function of the Haplic Plinthosol in Eastern Cape, South Africa. • The SMAF algorithms were sensitive to changes induced by CA strategies. • The impact of tillage practices were more dominant in the short term. • CT registered significantly higher SQI than NT in the short-term. • The soil biological indicators were more sensitive to CA strategies. [ABSTRACT FROM AUTHOR]

Climate change models predict an increase in climate variability in the future, with more rainfall extremes and greater risks, causing a negative impact on crops produced by smallholders in West Africa. Conservation Agriculture (CA) systems can be effective in mitigating yield loss in environments with increased weather risk. This study aimed to evaluate CA cropping systems that can minimize both economic and climatic risks under erratic climatic conditions in West Africa. We tested upland rice-based CA systems and conventional systems with tillage (CT), in rotation with maize in some of the cases, without and with fertilization, at different sowing windows in the Bouaké region, Côte d'Ivoire, from 2015 to 2020. Sowing in June showed in a higher rice yield (1183 kg ha-1 and 1370 kg ha-1 without and with fertilization, on average over the 2017–2020 period) than in March (521 kg ha-1 and 495 kg ha-1 without and with fertilization) or in July or August (335 kg ha-1 and 498 kg ha-1 without and with fertilization). During the first four years, rice yields tended to be lower under the CA systems than under the CT systems, especially when water availability was not a major constraint. However, after this transition period, and especially when water stress occurred, as in 2020, rice yields under CA systems (1835–2021 and 2147–2254 kg ha-1 without and with fertilization) were higher than under CT systems (1350 kg ha-1 and 1435 kg ha-1 without and with fertilization). CA systems having relatively longer duration for growing cover crops tended to produce higher upland rice yield grown in the subsequent season. In both CT and CA systems, the impact of fertilization on rice yield was small over the study period, and the mean rice yield increase due to fertilization was on average 451 kg ha-1 even when rice was sown in the summer season, resulting in negative economic return. These results indicate that whereas low-input CA upland rice-based systems together with optimizing sowing window for rice could be promising options for sustaining rice yield and mitigating yield loss in environments with increased weather risk, further research is needed for reducing transition period to CA systems in order to enhance their adoption by smallholder farmers. Desirable cover crops should be less labor-demanding, generate incomes from their products, and produce large biomass under erratic climatic conditions. • Conservation agriculture (CA) was compared to conventional tillage (CT) for 6 years. • In years 1–4, CT performed better than CA in favorable climatic years. • After 4 years, CA performed better than CT, especially in dry conditions. • Fertilization was not profitable in both CT and CA systems. • Associating cassava and stylo is a profitable option for soil regeneration. [ABSTRACT FROM AUTHOR]