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Foliar fertilization delivers essential nutrients directly to plant tissues, reducing excessive soil fertilizer applications that can lead to eutrophication following nutrient leaching. Foliar nutrient absorption is a dynamic process affected by leaf surface structure and composition, plant nutrient status, and ion physicochemical properties. We applied multiple methods to study the foliar absorption behaviors of manganese (Mn) and phosphorus (P) in nutrient-deficient spring barley (Hordeum vulgare) at two growth stages. Nutrient-specific chlorophyll a fluorescence assays were used to visualize leaf nutrient status, while laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to visualize foliar absorption pathways for P and Mn ions. Rapid Mn absorption was facilitated by a relatively thin cuticle with a low abundance of waxes and a higher stomatal density in Mn-deficient plants. Following absorption, Mn accumulated in epidermal cells and in the photosynthetically active mesophyll, enabling a fast (6 h) restoration of Mn-dependent photosynthetic processes. Conversely, P-deficient plants developed thicker cuticles and epidermal cell walls, which reduced the penetration of P across the leaf surface. Foliar-applied P accumulated in trichomes and fiber cells above leaf veins without reaching the mesophyll and, as a consequence, no restoration of P-dependent photosynthetic processes was observed. This study reveals new links between leaf surface morphology, foliar-applied ion absorption pathways, and the restoration of affected physiological processes in nutrient-deficient leaves. Understanding that ions may have different absorption pathways across the leaf surface is critical for the future development of efficient fertilization strategies for crops in nutrient-limited soils. Refereed/Peer-reviewed

Global demand for phosphorus (P) requires new agronomic practices to address sustainability challenges while increasing food production. Foliar P fertilization could increase P use efficiency; however, leaf entry pathways for inorganic phosphate ion (Pi) uptake remain unknown, and it is unclear whether foliar P applications can meet plant nutrient demands. We developed two techniques to trace foliar P uptake in P-deficient spring barley (Hordeum vulgare) and to monitor the effectiveness of the treatment on restoring P functionality. First, a whole-leaf P status assay was developed using an IMAGING PAM system; nonphotochemical quenching was a proxy for P status, as P-deficient barley developed nonphotochemical quenching at a faster rate than P-sufficient barley. The assay showed restoration of P functionality in P-deficient plants 24 h after foliar P application. Treated leaves reverted to P deficiency after 7 d, while newly emerging leaves exhibited partial restoration compared with untreated P-deficient plants, indicating Pi remobilization. Second, vanadate was tested as a possible foliar Pi tracer using high-resolution laser ablation-inductively coupled plasma-mass spectrometry elemental mapping. The strong colocalization of vanadium and P signal intensities demonstrated that vanadate was a sensitive and useful Pi tracer. Vanadate and Pi uptake predominantly occurred via fiber cells located above leaf veins, with pathways to the vascular tissue possibly facilitated by the bundle sheath extension. Minor indications of stomatal and cuticular Pi uptake were also observed. These techniques provided an approach to understand how Pi crosses the leaf surface and assimilates to meet plant nutrient demands.

Antimony is a priority environmental contaminant typically present as either the trivalent (Sb-III) or the pentavalent (Sb-V) oxidation state in aquatic systems. Both the toxicity and mobility of antimony are affected by its speciation, and thus the accurate measurement of antimony speciation is essential for investigating the behaviour of this contaminant in aquatic systems. Here we present a diffusive gradients in thin films (DGT) technique, which utilises a binding layer containing a thiol-based adsorbent (3-mercaptopropyl functionalised silica gel), for the selective measurement of Sb-III in surface waters and sediment porewaters. We also evaluated the Metsorb DGT technique, which has been previously reported to accurately measure Sb-V, for its ability to accumulate Sb-III and thus allow the measurement of total inorganic antimony. Both the mercapto-silica and Metsorb DGT techniques showed a high affinity for Sb-III, with uptake efficiencies > 97%. Elution efficiencies of 86.9 +/- 2.6% and 88.1 +/- 1.2% were obtained for mercapto-silica and Metsorb, respectively, with 1 mol L-1 H2O2 in 1 mol L-1 NaOH. The accumulation of Sb-III by these DGT techniques was linear with time (R-2 > 0.99) and unaffected by pH (4.07-8.05), ionic strength (0.001-1.0 mol L-1 NaCl), bicarbonate (1-15 mmol L-1), and an artificial seawater matrix (pH 8.34; salinity 34.8). Finally, the mercapto-silica DGT technique was applied to measure porewater concentrations of SbIII and AsIII in a contaminated freshwater sediment at high resolution. Refereed/Peer-reviewed

Category sustainable development and economically consolidated subjective factor of entities are the basis of well-structured productive forces, but also the main lever of its integral development. Therefore, in all conditions of working hard for the issues of sustainable development, it is given more attention. Solving the problems of governance of sustainable development in the entities and making optimal decisions for optimal economy, and (as part of the integrated economy) assumes the use of appropriate information subsystems. These are: operational records, statistical records and accounting records.

Antimony (Sb) and arsenic (As) are priority environmental contaminants that often co-occur at mining-impacted sites. Despite their chemical similarities, Sb mobility in waterlogged sediments is poorly understood in comparison to As, particularly across the sediment-water interface (SWI) where changes can occur at the millimeter scale. Combined diffusive gradients in thin films (DGT) and diffusive equilibration in thin films (DET) techniques provided a high resolution, in situ comparison between Sb, As, and iron (Fe) speciation and mobility across the SWI in contaminated freshwater wetland sediment mesocosms under an oxic-anoxic-oxic transition. The shift to anoxic conditions released Fe(II), As(III), and As(V) from the sediment to the water column, consistent with As release being coupled to the reductive dissolution of iron(III) (hydr)oxides. Conversely, Sb(III) and Sb(V) effluxed to the water column under oxic conditions and fluxed into the sediment under anoxic conditions. Porewater DGT-DET depth profiles showed apparent decoupling between Fe(II) and Sb release, as Sb was primarily mobilized across the SWI under oxic conditions. Solid-phase X-ray absorption spectroscopy (XAS) revealed the presence of an Sb(III)-S phase in the sediment that increased in proportion with depth and the transition from oxic to anoxic conditions. The results of this study showed that Sb mobilization was decoupled from the Fe cycle and was, therefore, more likely linked to sulfur and/or organic carbon (e.g., most likely authigenic antimony sulfide formation or Sb(III) complexation by reduced organic sulfur functional groups). Refereed/Peer-reviewed

The accurate measurement of solutes by DGT relies on the strength of their interaction with the binding layer.Mass transport of the analyte through the diffusive layer can only achieve a steady state when the analyte binds rapidly and irreversibly to the surface of the binding layer, so that the concentration of the solute at the interface between the binding layer and diffusive layer is effectively zero [1]. When this assumption is met, the DGT equation can be used to accurately determine the DGT-labile concentration of the analyte in the bulk solution. The first binding layer to be used with DGT consisted of a hydrogel containing Chelex 100, a commercially available resin containing iminodiacetic acid functional groups, which strongly bind transition metal ions via chelation [2]. The selectivity of Chelex 100 for transition metals over alkali and alkaline earth metals ensures that the major ions in natural waters (i.e. Na+, K+, Mg2+, Ca2+) do not interfere with the measurement of transition metals typically present in much lower concentrations (i.e. trace metals) [3]. Without the high degree of selectivity that Chelex 100 exhibits for trace metals, successful measurement of these analytes in awide variety of naturalwaterswould not be possible, due to competition for binding sites by major ions.