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Biomass-fuelled facilities generate alkaline and mineral-/nutrient-enriched co-product (ash) that has to be appropriately managed, and preferably reused. The assumption that wood biomass fly ash (BFA) could be used in chemical amelioration of soil acidity and fertility was tested by: i) physicochemical charac terisation of BFA and ii) bioassay with maize grown in acidic (pHKCl 4.68) hydromorphic soil amended with BFA (0e10% w/w). Scanning electron microscopy with energy dispersive X-ray spectroscopy and X ray diffraction revealed non- homogeneous (ir)regular spherical/porous agglomerated particle morphology and distinctive distribution of Si-/Ca-/K-based minerals, while secondary ion mass spec trometry, for the first time, confirmed their isotopic (six Ca, three Si/Mg and two K isotopes) diversity. BFA addition strongly shifted soil pHKCl (up to 9.1), raised salinity (by > 8.2-fold) and the content of most phytonutrients (up to 5.4-fold) ; however, BFA amendments at >1.25% restricted the maize root and shoot growth, likely due to alkaline stress as indicated by necrotic/chlorotic symptoms at >5.0% rate. The BFA amendments increased total concentration of metals in soil (without exceeding the levels recognised as contamination) ; however, phytoextraction of Cd, Zn, Mn, Cu and Mo was significantly supressed (Cd by almost 12-fold), confirming that BFA improved soil-plant metal immobilisation, shifting rhizosphere biogeochemistry towards chemisorption/precipitation reactions. Even though results revealed a strong liming and PeKeCaeMgeZneMneCu enrichment potential of BFA, to avoid possible negative envi ronmental implications (saline/alkaline stress, metal contamination, adverse effects on soil microbiome), quantitative and qualitative ex ante evaluation of the BFA/soil matrix combinations is essential before application to ameliorate suboptimal (acidic, low-nutrient) or metal-contaminated soils

In a conventional agriculture extensive use of pesticides is considered necessary to improve crop production but at the same time it can have negative effect on soil and water quality. One of the commonly used chemical in vineyards is glyphosate, a broad-spectrum, post emergence, non-selective herbicide with low mobility in soils due to its strong sorption. However, due to different transport processes present in environment it can still be transported to surface or groundwater resources. The main objective of this study was to evaluate glyphosate mobility at two contrasting vineyards in terms of soil properties and landscape position. Two locations were selected for the field trial: Baštica located on the flat coastal terrain (sandy soil), and Jazbina located on a hillslope terrain characteristic (clay soil). At both field sites, zero tension lysimeters were installed and water balance components monitored throughout the year. Undisturbed soil columns were taken from both sites and used to estimate mobility of pesticides by applying irrigation and a known dosage glyphosate (optimum field quantity) in a controlled environment. Water samples from lysimeters and leachate from soil columns were taken periodically and analyzed for active substances. In addition, soil samples were taken, and initial pesticides concentrations were measured, as well as the soil sorption capacity at each site. First results indicate that the sorption coefficient (Kd) was the main process limiting pesticide mobility in soil. Both soils have high capacity to adsorb glyphosate by the soil particles and organic matter present in the soil surface layer with Jazbina location having larger values as expected due to its higher clay content. It can be concluded that the possible losses of pesticides through surface runoff (e.g. colloidal transport) or by soil water preferential flow pathways are present with respect to different environmental condition at each site.

Vineyard fertilization practices is an important part of managing a vineyard since it impacts on vine growth, crop yield and wine quality. However, there are concerns about the of-site impacts of vineyard nutrient losses (especially of N and P) on the water quality standards. This research was carried out in two vineyards chosen as study plots (SP) for their heterogeneous pedological and climate characteristics: (SP1) located in the coastal wine-growing region, prevalent soil type is hydroameliorated- pipe drainage regosol and (SP2) located in the continental wine-growing region, prevalent soil type is Rigosol from Pseudogley of sloping terrains developed on Pleistocene loam and Pliocene clay substrata on a hillslope terrain. The physical and hydrologic characteristics of the soils were determined from soil samples collected from both SP. Lysimeters were installed at both SP and undisturbed soil columns taken from both locations for the assessment of nitrate and phosphate downward mobility through the soil profile by applying irrigation and a known nutrients concentration (in correspondence to the applied agricultural practices). Water samples from lysimeters and leachate from soli columns were taken periodically depending on rainfall occurrence and analyzed for nitrate, nitrite, ammonium and phosphate concentrations. The SP1 generated more intensive drainage and higher nutrient leaching than the SP2. This study demonstrates that the risk of nutrient leaching from each SP is a combination of factors associated with the soil texture, infiltration rate, field capacity. Still, the possibility of nutrients losses from vineyards soils through the erosion, surface runoff and subsurface leaching will be further studied.

Extensive use of pesticides in a conventional agriculture although necessary to improve crop production, may at the same time pose a threat to soil and water quality. Two main active substances were in focus of this research: glyphosate (broad-spectrum, post emergence, non-selective herbicide) and cypermethrin (synthetic pyrethroid insecticide), both commonly used in vineyards. Two locations were selected for the field trial: Baštica located on the flat coastal terrain, and Jazbina located on a hillslope terrain characteristic for vineyard production in the continental part of Croatia. At both field sites, zero tension lysimeters were installed and water balance components monitored throughout the year. Undisturbed soil columns were taken from both sites and used to estimate mobility of pesticides by applying irrigation and a known dosage of both pesticides (optimum field quantity) in a controlled environment. Water samples from lysimeters and leachate from soil columns were taken periodically and analyzed for active substances. In addition, soil samples were taken, and initial pesticides concentrations were measured, as well as the soil sorption capacity at each site. First results indicate that the sorption coefficient (Kd) was the main process limiting pesticide mobility in soil. Both pesticides have high capacity to be adsorbed by the soil particles and organic matter present in the soil surface layer. Thus, the possible losses of pesticides through surface runoff (e.g. colloidal transport) or by soil water preferential flow pathways will be further studied.