Pseudomonas fluorescens is a siderophore producing bacteria that is expected to alter the mobility and bioavailability of Cu in vineyard soils due to its ability to produce pyoverdine under iron deficiency. In this study, we monitored the effect of this bacterial species, particularly the production of siderophore, on the mobility and bioavailability of copper (Cu) and other elements using a spatialized approach. Two vineyard soils cultivated with sunflower, one non-carbonated (N-Carb) and one carbonated (Carb), were bioaugmented with P. fluorescens or not. 2D mapping using diffusive equilibration in thin films (DET) and diffusive gradient in thin films (DGT) was performed on day 15 after germination. At the end of the experiment, elements concentrations were measured in the plants and in the soil extracts (CaCl₂ 0.01 M). The results showed that the mobility of Cu and other elements (Fe, Al, Mn, Zn, N and P) was enhanced in both soils when bioaugmented. The chemistry of DET and DGT provided insights into the processes behind mobility, such as the presence and distribution of free metallophore spots (2–3.5 μM), interpreted as pyoverdine, which played a non-negligible role in Cu, Fe, Al mobilization and to a lesser extent in that of Mn, whereas pH played a limited role. DGT imaging showed that, depending on the speciation of metals in the soil solution, the increase in mobility measured by DET did not always increase bioavailability. Nevertheless, the concentration of copper in the aerial part of sunflower cultivated on the bioaugmented carbonated soil increased by 30% and copper content by 200%. These results identify bioaugmentation with P. fluorescens as a potential way to increase Cu phytoextraction, especially in carbonated soil, mainly because of its effect on plant growth but also on Cu bioavailability at the soil-plant interface.

荧光假单胞菌是一种产生铁载体的细菌，由于它能够在缺铁条件下产生吡维酮，预计会改变葡萄园土壤中铜的流动性和生物利用度。在这项研究中，我们使用空间化方法监测了这种细菌物种，特别是铁载体的产生，对铜 (Cu) 和其他元素的迁移率和生物利用度的影响。用向日葵种植的两种葡萄园土壤，一种非碳酸化 (N-Carb) 和一种碳酸化 (Carb)，用荧光假单胞菌进行生物增强或不。在发芽后第 15 天进行使用薄膜中的扩散平衡 (DET) 和薄膜中的扩散梯度 (DGT) 的 2D 映射。在实验结束时，测量了植物和土壤提取物中的元素浓度 (CaCl ₂0.01 M）。结果表明，当生物强化时，Cu 和其他元素（Fe、Al、Mn、Zn、N 和 P）在两种土壤中的迁移率均有所提高。DET 和 DGT 的化学提供了对迁移背后过程的见解，例如游离金属团斑点（2-3.5 μM）的存在和分布，被解释为pyoverdine，它在 Cu、Fe、Al 迁移和Mn 的影响较小，而 pH 的作用有限。DGT 成像显示，根据土壤溶液中金属的形态，DET 测量的迁移率增加并不总是增加生物利用度。尽管如此，在生物强化碳酸盐土壤上种植的向日葵地上部分的铜浓度增加了 30%，铜含量增加了 200%。这些结果确定了生物强化P. fluorescens作为增加铜植物提取的潜在方式，特别是在碳化土壤中，主要是因为它对植物生长的影响，而且对土壤-植物界面处的铜生物有效性也有影响。