University of Córdoba (Spain)

About: University of Córdoba (Spain) is a education organization based out in Cordova, Spain. It is known for research contribution in the topics: Population & Catalysis. The organization has 12006 authors who have published 22998 publications receiving 537842 citations. The organization is also known as: University of Córdoba (Spain) & Universidad de Córdoba.

Analytical study of aromatic series in sherry wines subjected to biological aging.

Abstract: The odor activity values (OAVs) for 49 aroma compounds in commercial sherry pale white wines were grouped, according to the similarity of their aroma descriptors, into nine odor classes with a view to establishing the aroma profile for this type of wine. The results revealed the profile to be largely comprised of the series named “fruity” and “balsamic”, mainly as a result of the 1,1-diethoxyethane content in the wines. The same series were calculated from the OAVs obtained in biological aging experiments, carried out with selected strains of the flor yeasts Saccharomyces cerevisiae and Saccharomyces bayanus, over a period of 9 months. Based on the aroma profiles thus obtained, after 6 months of aging the latter race yielded OAVs for the fruity and balsamic series not significantly different (p < 0.05) from those for commercial wines aged for 5 years. However, except for the series named “solvent”, all others exhibited lower values in the experiments carried out with selected strains than in the commercia...

Phosphorus fertilizer recovery from calcareous soils amended with humic and fulvic acids

Abstract: Precipitation of Ca phosphates negatively affects recovery by plants of P fertilizer applied to calcareous soils, but organic matter slows the precipitation of poorly soluble Ca phosphates. To study the effect of high molecular weight organic compounds on the recovery of applied P, a mixture of humic and fulvic acids was applied to calcareous soils with different levels of salinity and Na saturation which were fertilized with 200 and 2000 mg P kg−1 as NH4H2PO4. Recovery was measured as the ratio of increment in Olsen P-to-applied P after 30, 60 and 150 days, and associated P forms were studied using sequential chemical fractionation and 31P NMR spectroscopy. Application of the humic-fulvic acid mixture (HFA) increased the amount of applied P recovered as Olsen P in all the soils except in one soil with the highest Na saturation. In soils with high Ca saturation and high Olsen P, recovery increased from 40% at a 5 g HFA kg−1 amendment rate (30 days incubation and 200 mg P kg−1 fertilizer rate). This is ascribed to inhibition of the precipitation of poorly soluble Ca phosphates, consistent with the sequential chemical extraction (reduction of the HCl extractable P) and P concentration in 0.01 M CaCl2 (1:10 soil:solution ratio) extracts. 31P NMR spectra revealed that in non-amended samples, most spectral shifts were due to poorly soluble P compounds (carbonate apatite); on the other hand, at the 5 g HFA kg−1 rate, significant amounts of amorphous Ca phosphate and dicalcium phosphate dihydrate (DCDP) were identified. The increase in the recovery of applied P due to HFA reveals a positive effect of the application of organic matter as soil amendments on the efficiency of P fertilizers and also explains that manures and other organic sources of P were more efficient increasing available P than inorganic P fertilizers in calcareous soils.

Functional diversity enhances the resistance of ecosystem multifunctionality to aridity in Mediterranean drylands

Abstract: Summary � We used a functional trait-based approach to assess the impacts of aridity and shrub encroachment on the functional structure of Mediterranean dryland communities (functional diversity (FD) and community-weighted mean trait values (CWM)), and to evaluate how these functional attributes ultimately affect multifunctionality (i.e. the provision of several ecosystem functions simultaneously). � Shrub encroachment (the increase in the abundance/cover of shrubs) is a major land cover change that is taking place in grasslands worldwide. Studies conducted on drylands have reported positive or negative impacts of shrub encroachment depending on the functions and the traits of the sprouting or nonsprouting shrub species considered. � FD and CWM were equally important as drivers of multifunctionality responses to both aridity and shrub encroachment. Size traits (e.g. vegetative height or lateral spread) and leaf traits (e.g. specific leaf area and leaf dry matter content) captured the effect of shrub encroachment on multifunctionality with a relative high accuracy (r 2 = 0.63). FD also