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A field experiment was performed with the aim to assess the amount of penconazole losses during field application and the spatial variability of penconazole concentration in a vineyard soil, under two different management techniques (tilled and grass covered). The field dissipation of penconazole under the two techniques was also followed for 114 days, highlighting the effects of spatial variability of the initial concentration and of the grass covering in terms of the different soil metabolic activity. Data found show that a high percentage of penconazole, from 42.5 % to 67.43 %, can reach the soil during the treatments, despite the fact that penconazole is applied to the foliage. The high values of the coefficient of variation for data within rows show considerable variability in all applications, ranging from 30 to 65 in the first application, from 35 to 79 in the second and from 36 to 75 in the third. Since the applications of penconazole occurred under almost same climatic conditions in terms of wind speed and direction, the high variability of concentration of penconazole found within mid-rows was attributed to the uneven slope of the vineyard causing an irregular speed of the sprayer equipment. However, least significant differences of the mean values did not end in a significant difference of penconazole concentration among mid-rows for all applications, indicating that the variability between rows does not contribute to the overall variability. The calculated half-life values for penconazole in tilled soil were 62.4 days for tilled and 33.0 for grassed soil, highlighting the tendency of penconazole to faster dissipate in grassed than in tilled soil. Grassed soil was characterised by a higher metabolic activity in terms of microbial biomass carbon content, basal respiration and total hydrolytic activity, than tilled soil. A significant correlation between penconazole dissipation and total hydrolytic activity, was found. The faster dissipation of penconazole in grassed soil was attributed to the higher amount of the total hydrolytic activity which, in grassed soil, was 1.5 fold-higher than in tilled soil.

A laboratory experiment was carried out to test the efficiency of a bio-mixture made up of pruning residues at two (PR2) and five (PR5) years of composting and wheat straw (STW) in the biological cleaning of water contaminated by different mixtures of fungicides usually employed in vineyards. The experiment was conducted and reproduced at a scale of 1:100 of operating field conditions. Commercial formulates of penconazole (PC), (RS)-1-[2-(2,4-dichlorophenyl)pentyl]-1H-1,2,4-triazole), dimetomorph (DM), (EZ)-4-[3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)acryloyl]morpholine), azoxystrobin (AZ), (methyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate), iprovalicarb (IP), (isopropyl 2-methyl-1-[(RS)-1-p-tolylethyl]carbamoyl-(S)-propylcarbamate), metalaxyl (MX), (methyl N-(methoxyacetyl)-N-(2,6-xylyl)-DL-alaninate), fludioxonil (FL), (4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile) and cyprodinil (CY), (4-cyclopropyl-6-methyl-N-phenylpyrimidin-2-amine) were mixed in water and discharged into the bio-mixture following the time schedule of the treatments carried out in the grapevine in real field conditions. At each treatment, contaminated water with fungicides was circulated repeatedly through the bio-mixture to enhance the sorption of fungicides. In fact, it retained them between 98-100% with the exception of MX of which it was able to retain only 90.5%. The adsorption/desorption experiment showed that repeated circulation of water, instead of enhancing MX retention, can easily remove about 30% of MX already adsorbed by the bio-mixture. This finding suggests that water contaminated by very mobile pesticides should be discharged at the end of field treatments without re-circulating the water in order to avoid the release of pesticides weakly adsorbed on the bio-mixture.

To investigate the effects of moist olive husks (MOH-residues) on soil respiration, microbial biomass, and enzymatic (o-diphenoloxidase, beta-glucosidase, dehydrogenase and alkaline phosphatase) activities, a silty clay soil was incubated with 0 (control), 8 x 10(3) (D), 16 x 10(3) (2D) and 80 x 10(3) (10D) kg ha-1 of MOH-residues on a dry weight basis. Soil respiration and microbial biomass data indicated that the addition of MOH-residues strongly increased microbial activity proportionally to the amounts added. Data of qCO2 suggested that the respiration to biomass ratio of the microbial population was strongly modified by MOH-residues additions during the first 90 days of incubation. The qCO2 data suggested a low efficiency in energy yields from C oxidation during the first 2 months of soil incubation. qFDA seemed to be relatively unaffected for treatments D and 2D as compared to the control, but was significantly lowered by the application of 10D, showing the lowest hydrolytic activity of microbial biomass in this treatment up to 360 days of incubation. o-Diphenoloxidase activity was delayed, and this delay was extended with the addition of larger quantities of MOH-residues. Alkaline phosphatase, beta-glucosidase and dehydrogenase activities were in line with the findings on microbial biomass changes and activities. The biological and biochemical data suggest that the addition of a large quantity of MOH-residues (80 x 10(3) kg ha-1) strongly modifies the soil characteristics affecting the r- and K-strategist populations, and that these changes last for at least the 360 days of incubation. The data also suggest that application rates exceeding 16 x 10(3) kg ha-1 are not recommended until the agro-chemical and -physical functions of the soil are further studied.