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Bare soil and inadequate soil tillage are emerging problems worldwide that result in soil quality impoverishment and contribute to global warming. To reverse this situation and to improve soil structure and carbon and nitrogen storage capacity, implementing sustainable land management (SLM) practices is needed. This study evaluates the combined effect of different SLM practices (tillage with/without compost addition) and cover crop types (native/seeded cover crops) and their management (mowing or grazing) on soil organic carbon (SOC) and total nitrogen (tN) stabilization in rainfed semiarid Mediterranean almond orchards under a range of edapho‐climatic conditions. To do so, the long‐term effects of different SLM practices, such as reduced tillage plus seeded cover crops (RT + SCC), reduced tillage plus native cover crops (RT + NCC) and no tillage plus native cover crops (NT + NCC) on soil water‐stable aggregates distribution and different organic carbon and nitrogen pools were estimated at a depth of 0–20 cm (plough layer) at five experimental sites. SLM practices, implemented over 5–12 years (depending on the experimental site), were compared with the traditional tillage (TT) carried out by farmers, which consisted of three‐five passes per year to maintain soil bare. Our results demonstrate the cross‐site potential of combining reduced tillage and cover crops (regardless of seeded or native) for improving SOC and tN sequestration and stabilization. However, the magnitude of the effect of SLM practices on SOC and tN stabilization depended heavily on the local environmental and management conditions. As seeded cover crops (RT + SCC) accelerated SOC and tN stabilization compared with native cover crops (RT + NCC and NT + NCC), its implementation in these semiarid agro‐ecosystems is recommended. However, no tillage implemented as an isolated practice is not recommended in soils prone to compaction, but managed in combination with other SLM practices, such as compost addition or mulching, can be effective for SOC and tN sequestration and stabilization over time. [ABSTRACT FROM AUTHOR]

The objective of this work is to evaluate the impact of regenerative agriculture alternatives in rainfed almond crops on a range of ecosystems services. A Multi-Criteria Analysis (MCA) was conducted to evaluate the different land management alternatives integrating different quantitative and qualitative indicators based on long-term field research. Three land management alternatives were analyzed: (i) conventional management, (ii) native cover crops, and (iii) seeded cover crops. MCA was able to evaluate the performance of the three alternatives considering different priorities of two groups of farmers (conventional and regenerative) and score the different scenarios. The alternative of natural cover crops had the best score in almost all the groups of ecosystem services and economic indicators. The sustainability, acceptance, and stability of the scenarios were achieved and provided an integrated view of impacts that can help decision making. [ABSTRACT FROM AUTHOR]

The implementation of alley cropping in orchards can be a sustainable strategy to increase farm productivity by crop diversification and contribute to climate change mitigation. In this research, we evaluated the short-term effect of alley cropping with reduced tillage on soil CO 2 and N 2 O emissions and soil total organic carbon (TOC) in an almond orchard under Mediterranean rainfed conditions. We compared an almond monoculture with tillage in all plot surface (MC) with almond crop with reduced tillage and growth of Capparis spinosa (D1) and almond crop with reduced tillage and growth of Thymus hyemalis (D2). For two years, soil CO 2 and N 2 O were measured, with soil sampling at the start and end of the experimental period. Results showed that CO 2 emission rates followed the soil temperature pattern, while N 2 O emissions were not correlated with temperature nor moisture. Soil CO 2 emissions were significantly higher in MC (87 mg m -2 h -1 ), with no significant differences between D1 and D2 (69 mg m -2 h -1 ). Some peaks in CO 2 effluxes were observed after tillage operations during warm days. Soil N 2 O emission rates were not significantly different among treatments. Cumulative CO 2 and CO 2 equivalent (CO 2 e) emissions were significantly highest in MC. When CO 2 e emissions were expressed on a crop production basis, D2 showed the significantly lowest values (5080 g kg -1 ) compared to D1 (50,419 g kg -1 ) and MC (87,836 g kg -1 ), owing to the high thyme yield, additional to the almond yield. No production was obtained for C. spinosa, since at least two more years are required. TOC did not change with time in MC neither D1, but it significantly increased in D2 from 3.85 g kg -1 in 2019 to 4.62 g kg -1 in 2021. Thus, alley cropping can contribute to increase the agroecosystem productivity and reduce CO 2 emissions. However, it is necessary to grow evergreen alley crops such as thyme to obtain short-term increases in soil organic matter. Thus, to estimate increases in TOC with alley cropping, the plantation density and the period required by the crop to cover most of the surface are essential factors at planning the cropping strategy., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Raul Zornoza reports financial support was provided by European Commission., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)