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No-till practices reduce soil erosion, conserve soil organic carbon, and enhance soil fertility. Yet, many factors could limit their adoption in organic farming. The present study investigated the effects of tillage and cover cropping on weed biomass, plant growth, yield, and fruit quality of an organic processing tomato (Solanum lycopersicon L. var. Elba F1) over two seasons (2015–2017). We compared systems where processing tomato was transplanted on i) tilled soil following or not a winter cover crop (Trifolium squarrosum L.) and with/without a biodegradable plastic mulch; and ii) no-till where clover was used, after rolling and flaming, as dead mulch. Tomato in no-till suffered from high weed competition and low soil nitrogen availability leading to lower plant growth, N uptake, and yield components with respect to tilled systems. The total yield in no-till declined to 6.8 and 18.3 t ha−1 in 2016 and 2017, respectively, with at least a 65% decrease compared to tilled clover-based systems. No evidence of growth-limiting soil compaction was noticed but a slightly higher soil resistance was in the no-till topsoil. Tillage and cover crop residues did not significantly change tomato quality (pH, total soluble solids, firmness). The incorporation of clover as green manure was generally more advantageous over no-till. This was partly due to the low performance of the cover crop where improvement may limit the obstacles (i.e., N supply and weed infestation) and enable the implementation of no-till in organic vegetable systems. [ABSTRACT FROM AUTHOR]

In greenhouses, where intensive systems are widely used for organic production, the differences between "conventionalized" and agroecological approaches are especially evident. Among the agronomic practices, green manure from agroecological service crops (ASCs) and organic amendments represent the main tools for soil fertility management with respect to the substitution of synthetic fertilizer with organic ones (the input substitution approach). Over a two-year organic rotation, we compared a conventionalized system (SB) and two agroecological systems, characterized by ASC introduction combined with the use of manure (AM) and compost (AC) amendments. A system approach was utilized for the comparison assessment. For this purpose, agronomic performance, soil fertility and the density of soil arthropod activity were monitored for the entire rotation. The comprehensive evaluation of the parameters measured provided evidence that clearly differentiated SB from AM and AC. The drivers of discrimination were soil parameters referring to long term fertility and soil arthropod dynamics. The study confirmed the higher productivity of SB but also no positive impact on soil fertility and soil arthropods, as highlighted by AM and AC. Based on the results, a trade-off between productivity and the promotion of long-term ecosystem diversity and functioning is needed for the assessment of systems of organic production. [ABSTRACT FROM AUTHOR]

Cover crops provide many ecosystem services, such as soil protection, nitrate pollution of water mitigation, and green manure effects. However, the impact of cover crops on soil water balance is poorly studied, despite its potential impact on groundwater recharge. Some studies reported a reduction of the water drainage due to an increase of the evapotranspiration by plant cover transpiration. However, there is no real consensus on the intensity of this phenomenon, which highlights the importance to quantify the impact of cover crops on drainage compared to that of bare soil. We performed a meta-analysis of published papers presenting studies on the impact of cover crops on drainage compared to that of bare soil under temperate climates. Of the 436 papers identified, 28 of them were included in the analysis based on criteria required for performing a relevant meta-analysis. The originality of our study lies in two following results: (1) the quantification of drainage reduction with cover crops by a mean effect size of 27 mm compared to that of bare soil and (2) within the large variability of soils, climates, and cropping systems, no main determining factor was found significant to explain the variability of water drainage reduction. The cover crops provide a service of nitrate pollution mitigation, but the drainage reduction could be considered as a disservice, because they can lead to a reduction in groundwater recharge due to a higher evapotranspiration in comparison to bare soil. This highlights the need of research for optimizing trade-offs between services and disservices of cover crops for water balance. [ABSTRACT FROM AUTHOR]

The role played by certain environmental factors in the improvement of wine quality has been well studied and proven in many researches. These permitted to become aware of the existence of a terroir factor which represents all the natural features (in terms of soil, climate and terrain) and human practices which together make wine production of a certain area unique, in terms of production method and wine properties. In this research, a soil modelling approach was used to assess how terroir altered in the past and how it will change in the next decades, and the influence of its evolution on wine quality.After the identification of the components making up the terroir in the research area (Vino Nobile di Montepulciano D.O.C.G. district, south-east Tuscany, Italy), the relations between terroir and viticultural parameters have been investigated from the statistical point of view, in order to find regression models which can be used to predict grape (and then wine) peculiarities, starting from the soil and other environmental features. The evolution through time of the environmental factors which were recognized to play a role in building the wine quality was then studied using the SoilGen model, both in the past and in the future (from 970 BC to 2099 AD), under different scenarios of climate change (RCP 4.5 and RCP 8.5) and soil management strategies (Organic-conservative, Organic with cover crops used as green manure, Tillage without cover crops and removing pruning residues).The model output served as a base to predict viticultural parameters using the same regression identified in the beginning of the research, under climate change and different agricultural practices. The results revealed an important change in grape properties over the last 500 years, due to a variation in the (micro-)climate of the area rather than land management by vignerons. When the effect of a drastic climate change in the upcoming 80 years was simulated, it was shown a severe quality decrease of those grape properties (playing a role in building wine peculiarities) which were predicted starting from variations in soil and climate. Nevertheless, some soil management practices seem to offset the decrease in terroir by mitigating the negative modifications in terroir caused by climate change.This new kind of approach permitted to get knowledge of how grapevine properties will evolve according to the change in its terroir settings, and this may lead to the adoption of appropriate vineyard management strategies in order to mitigate the climate change and to preserve the uniqueness of Vino Nobile di Montepulciano DOCG. [ABSTRACT FROM AUTHOR]