Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background and aims</jats:title> <jats:p>Intercropping of grain legumes and cereals in European agriculture can provide benefits, such as an increase in yields, yield stability and weed suppression. Interactions between crops in intercropping may depend on spatial heterogeneity in soil conditions, which are present on farmers’ fields. Understanding the effect of within-field variation in soil conditions on interspecific interactions might increase the benefits of intercropping by within-field adjustment of the agronomic management.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Crop performance and weed dry matter were assessed together with several soil properties in grids within three large field experiments at two sites (Germany and Sweden) and during two years. Each experiment was comprised of several strips sown either with the two sole crops oat (<jats:italic>Avena sativa</jats:italic> L.) and field pea (<jats:italic>Pisum sativum</jats:italic> L.) or an oat-pea intercrop.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>The response of crop performance to within-field variability in soil conditions was mostly species-specific. Yield stability of intercropping was consistently higher compared with pea, but not compared to oat. The highest land equivalent ratio was found for an additive intercropping design under a higher water availability. In this experiment, yield stability of both intercropped pea and oat were lower, which might be expected as a result of within-field variation in interspecific interactions. Intercropping reduced weed dry matter compared to pea, for which one experiment indicated an increase in weed dry matter with nutrient availability.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusion</jats:title> <jats:p>The experimental design and the developed statistical analysis can contribute to further research about spatial variations in interspecific interactions in intercropping, which will improve the understanding of plant-plant and plant-soil interactions.</jats:p> </jats:sec>

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background and aims</jats:title> <jats:p>Agroforestry, whereby trees are associated with crops and/or livestock, is expected to mitigate nitrogen (N) losses from agriculture. However, little is known about how nitrification potential, an important process that drives N losses, is affected by agroforestry systems. This study aimed to investigate the effect of different silvopastoral agroforestry systems on soil nitrification potential.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Nitrification potential was evaluated in two agroforestry systems (hedgerow and alley cropping) associated with temporary grasslands in Brittany, France. In each system, soil was sampled along a transect spanning from the center of the tree row into the grass alley. Soil nitrification potential was determined <jats:italic>ex situ</jats:italic> and was explained by univariate and multivariate analysis of variables describing vegetation, physicochemical soil properties, and soil organisms.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>Nitrification potential differed between the two agroforestry systems and among the positions in relation to the trees. In the alley cropping system, nitrification potential was on average 1.5 times higher in the tree row than at 1.5 and 10 m into the grass alley, while in the hedgerow system, nitrification potential at 1.5 m into the grass alley was on average 40% lower than at 10 m into the grass alley. Nitrification potential was strongly correlated with soil pH, whereas no correlation was observed between nitrification potential and community size of soil nitrifiers.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusion</jats:title> <jats:p>Our results point out the diverse effects of agroforestry systems on nitrification, a key soil process that is involved in the regulation of N losses.</jats:p> </jats:sec>

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p>Precipitation of Zn phosphates may limit Zn availability in cogranulated P fertilizers. We assessed whether the Zn availability of Zn could be improved by post-granulation acid treatment.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Uncoated Zn-fortified monoammonium phosphate granules were compared with sulfuric acid-coated granules in which Zn was either cogranulated or dissolved in the acid coating. Spatially resolved XRF and XANES was used to assess the distribution and speciation of Zn in the granules (before and after incubation in soil) and in the exposed soil. The amount of Zn remaining in the granule was determined after incubation in various soils. The effect of acid coating rate on corn yield was determined in a highly Zn-deficient soil in a pot trial.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>The speciation of Zn in the untreated granules was dominated by Zn phosphates. In the sulfuric acid treatments, sulfate species accounted for ~ 45% (if cogranulated) or ~ 80% (if coated) of the Zn. After one week incubation in soil, 10–86% of the added Zn remained in the residual granule, mostly as sparingly soluble compounds. The Zn speciation in the soil near the granule was dominated by Zn phosphates irrespective of treatment, but Zn moved further away from the application site in the acid treatments, as more Zn was released from the granule. In the pot trial, the dry matter yield increased by 70% at a coating rate of 0.75% H<jats:sub>2</jats:sub>SO<jats:sub>4</jats:sub> compared to the uncoated control.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Post-granulation acid treatment of Zn-fortified P fertilizers is an effective way to enhance the phytoavailability of fertilizer Zn.</jats:p> </jats:sec>