Individuating strategies to reduce greenhouse gas (GHG) emissions from agricultural soil, while preserving crop yield and the quality of products is needed. The major GHG emitted from agricultural soils is nitrous oxide (N₂O) and its production is largely influenced by the amount of nitrogen (N) fertilizers applied and by the soil conditions, such as water content and temperature. The cultivation of processing tomato may lead to high N losses because it is characterized by a high frequency of irrigation events and N fertilizer applications. In this study we assessed the effect of reducing water from reintegration of 100% of water missing to field capacity (Ir2) to 50% (Ir1) and N applied, by 30% from 170 kg N ha^-1 (N2) to 120 kg N ha^-1 (N1) and 100% from N2 to 0 kg N ha^-1 (N0), on yield, fruit quality and GHG emissions from soil in tomato cultivated under fertigation for two growing seasons (2014, 2015). We highlighted a great variability of results, both on GHG emissions from soil and on tomato productivity, due to differences in meteorological conditions in the two growing seasons. Higher marketable yield of tomato was recorded in N2 than in N1 only in 2014 and in Ir2 than Ir1 only in 2015, while reducing the agricultural inputs did not reduce the fruit quality. Carbon dioxide and nitrous oxide emissions were higher in 2015, while soil was a sink for methane in both growing seasons. We highlighted a general trend in lower nitrous oxide emissions with reduced water and N fertilizer rate, even if these emissions were largely variable in time and space. In particular, yield-scaled N₂O emissions were lower in Ir1 than in Ir2, suggesting that a reduction of the irrigation level may be a suitable strategy for mitigating N₂O emissions from tomato cultivated under fertigation in a Mediterranean environment.

需要制定个性化策略以减少农业土壤中的温室气体 (GHG) 排放，同时保持作物产量和产品质量。农业土壤排放的主要温室气体是一氧化二氮 (N ₂ O)，其产量在很大程度上受施氮 (N) 肥料的量和土壤条件（如含水量和温度）的影响。加工番茄的种植可能导致高氮损失，因为它的特点是灌溉事件和氮肥施用频率高。在这项研究中，我们评估了从 100% 缺水到田间持水量 (Ir2) 到 50% (Ir1) 和施氮（从 170 kg N ha ^-1 (N2) 到 120 kg）减少 30% 的影响氮公顷^-1(N1) 和 100% 从 N2 到 0 kg N ha ^-1(N0)，关于在两个生长季节施肥栽培的番茄的产量、果实质量和土壤温室气体排放量（2014 年、2015 年）。由于两个生长季节的气象条件不同，我们强调了土壤温室气体排放和番茄生产力的结果差异很大。仅在 2014 年，N2 的番茄可销售产量高于 N1，而 2015 年的 Ir2 高于 Ir1，而减少农业投入并没有降低果实质量。2015 年二氧化碳和一氧化二氮的排放量更高，而土壤在两个生长季节都是甲烷的汇。我们强调了随着水和氮肥用量减少，一氧化二氮排放量降低的总体趋势，即使这些排放量在时间和空间上变化很大。特别是，产量成比例的 N ₂Ir1 中的 O 排放量低于 Ir2，这表明降低灌溉水平可能是减轻地中海环境中在施肥下种植的番茄的N ₂ O 排放量的合适策略。