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The influence of sugar foam amendment on the moisture-retention properties of three profiles of an acidic vineyard soil in Retuerta del Bullaque (Ciudad Real, Spain) has been studied. The values obtained for the surface horizons of modified soils and the original soil (under natural vegetation) were compared, as were those for the surface and subsurface horizons of the liming profiles. The water-retention curves (drying curve) were determined in triplicate on the sieved soil with Richards plates and the field capacity (FC), permanent wilting point (PWP), and available water-retention capacity (AWRC) were calculated. In the original soil FC, PWP, and AWRC values were greater than the average values for the amended soils (36.5 percent, 15.1 percent, and 21.5 percent versus 23.5 percent, 10.35 percent, and 13.1 percent, respectively). Comparison of the surface horizons and the subsurface horizons of the three profiles showed that the values for the AWRC were greater in the former (13.1 percent, 12.5 percent, and 14 percent for P1, P2, and P3, respectively) than in the latter (11.9 percent, 9 percent, and 8.6 percent for P1, P2, and P3, respectively), although FC and PWP were lower in A horizons than in B horizons. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to evaluate the combined effects of liming and behaviour of Sarcocornia fruticosa as a strategy of phytomanagement of metal polluted salt marsh soils. Soils were taken from two polluted salt marshes (one with fine texture and pH∼6.4 and the other one with sandy texture and pH∼3.1). A lime amendment derived from the marble industry was added to each soil at a rate of 20gkg−1, giving four treatments: neutral soil with/without liming and acidic soil with/without liming. Cuttings of S. fruticosa were planted in pots filled with these substrates and grown for 10 months. The pots were irrigated with eutrophicated water. As expected, lime amendment decreased the soluble metal concentrations. In both soils, liming favoured the growth of S. fruticosa and enhanced the capacity of the plants to phytostabilise metals in roots. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the effects of the particle size (2–4 mm, 0.5–2 mm, 0.25–0.5 mm and less than 0.25 mm) of magnesium limestone and the method of application (in a single dose or split in three yearly doses), on the forms of Al in the solid and liquid phases of an acid Galician soil destined for pasture production. Monitoring the experimental plots over a period of 3 years showed that the plots treated with a single application of the finest limestone (<0.25 mm) exhibited the highest pH and the lowest concentrations of exchangeable Al, with less than 10% Al saturation throughout the period of study. The average values of pH in water along the period of study were 5.30 in the most effective treatment and 5.06 in control plots. The average values of aluminium saturation were 6.5% in the most effective treatment and 16.9% in control plots. One year after liming, the plots treated with a single application of the finest limestone presented also the highest concentrations of weakly stable organo-aluminium complexes in the solid phase and of organically bound Al in the soil solution, as well as the lowest concentrations of labile Al, while no Al3+ (considered the most toxic Al species) was detected. Over time non-crystalline inorganic Al tended to precipitate, apparently at the expense of exchangeable Al and/or Al bound to the organic matter. The application of the finest limestone split in three doses (until completion of 3 t ha−1 in the third year of the study) was less effective than the application of a single dose. The plots treated with the coarsest limestone (between 2 and 4 mm) and the control plots provided similar results for all parameters throughout the three years of the study. In the former the exchangeable Al was higher than 20% and the concentration of labile Al was the highest of all plots. [Copyright &y& Elsevier]

•Effect of no-tillage (NT) and liming on a rainfed oat-vetch mixture was evaluated. •Mycorrhizal root colonization of both crops was higher under NT and in limed plots. •Oat N content was increased by liming and NT while N vetch content only by liming. •Plant P contents were unaffected and the N:P ratio was increased by liming and NT. •Crop yields were increased by NT and liming showing a positive interaction. The combination of no-tillage (NT) and liming has been proposed as feasible means to restore degraded acid soils. However, the synergistic effect of both practices on nutrient acquisition by crops has not been addressed. Similarly, the simultaneous impact on arbuscular mycorrhizal fungi (AMF) is under-investigated despite its essential role in plant growth and nutrient uptake, especially under stress conditions. We evaluated the plant growth, nutrient acquisition and mycorrhizal root colonization at three stages during a growing season along with soil properties of a rainfed oat (Avena sativa L.) and vetch (Vicia sativa L.) mixture under Mediterranean condition. The experiment was located in south-west Spain where tillage type (no tillage: NT and traditional tillage: TT) and lime application were evaluated in a full factorial design. Liming raised soil pH, increased soil calcium and magnesium availability and stimulated the microbial activity while NT enhanced soil carbon content. Both practices improved oat biomass production (40 times at biomass harvest) and root colonization of both crops (80 % and 60 % higher respect to TT without liming in oat and vetch, respectively). Liming enhanced vetch biomass production (20 times at harvest) and foliar N content, while NT increased foliar N content of oat. Plant phosphorous (P) contents were unaffected by the treatments. The high N:P of both crops indicates P limitation despite of the high soil P content. The P limitation together with the increased N supply could lead to strengthening of mutualism between plants and AMF, where P acquisition through AMF is stimulated in order to take advantage of the "luxury" N supply provided by NT and liming. Thus, both practices together increase nutrient use efficiency by stimulating crop-microbe interactions. [ABSTRACT FROM AUTHOR]