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Ecological intensification, based on agricultural practices that promote ecosystem services, has been recently proposed to match crop yield and environmental concerns. Two-year experiments were conducted in a Mediterranean environment. The treatments were: (i) four intensification levels (common vetch (CV), ryegrass (RG), bare soil without Nitrogen (N) fertilization (Control-N0) and with 100 kg ha−1 of N fertilization (Control-N100) applied during pepper cultivation), and(ii) two soil tillage [soil tillage at 15 cm and 30 cm of soil depth (ST-15 and ST-30, respectively)]. The field experiment was disposed in a randomized block design with three replications. Cover crop, soil samples, and pepper samples were collected for analysis. Soil available nitrogen increased after soil tillage, especially in CV, which showed the highest fruit yield. The reduced soil N availability in RG decreased fruit yield and N uptake. The agro-physiological efficiency of pepper was similar in common vetch and Control-N100, while it was low in ryegrass. However, the adoption of RG increased the soil organic matter more than both control treatments, which, in turn, caused a depletion of soil organic matter. Moreover, reduced tillage practices for green manuring that both cover crops arepreferable to reduce external inputs in terms of fuel saving and farming operations.

Agricultural practices greatly influence the bioavailability of heavy metals. Arsenic (As) is a heavy metal identified as a concern due to its potential impact on human health. Two-year field experiments were performed to evaluate the effect of cropping system on As accumulation in tomato, sweet pepper and zucchini. The treatments were: (i) conventional system based on common practices of the area; and (ii) alternative systems based on cultivation of hairy vetch (Vicia villosa Roth.) in no-tillage before vegetable crops. Randomized block design with three replications was adopted. Soil and plant samples (fruits, leaves, stems and roots) were collected at crop harvesting. Plant samples were weighed and analyzed to evaluate As content. Soil chemical analyses were performed to evaluate the total organic carbon and nitrogen content. The As accumulation observed in plant samples of tomato, sweet pepper and zucchini resulted always low in the alternative system, except in fruits where As accumulation was similar between the systems. The increase of soil organic matter observed in alternative system probably caused a reduction of As accumulation into crop tissues. Therefore, hairy vetch cultivation in no-tillage could be a suitable strategy to reduce the As uptake of vegetable crops in geogenic contaminated soils.