Search results for "Nitrogen"
showing 10 items of 1200 documents
L'inoculation des légumineuses en France : un exemple de coopération entre l'INRA de Dijon et les fabricants d'inoculant
2013
EAMERSslides (31 diapositives); L'inoculation des légumineuses en France : un exemple de coopération entre l'INRA de Dijon et les fabricants d'inoculant
One-pot synthesis of fluorinated 2-amino-pyrimidine-N-oxides. Competing pathways in the four-atom side-chain rearrangements of 1,2,4-oxadiazoles
2006
Abstract Trifluoromethylated 2-amino-pyrimidine N-oxides have been synthesized by reaction of the 3-amino-5-methyl-1,2,4-oxadiazole with trifluoromethyl-β-diketones in the presence of perchloric acid, followed by hydrolysis. In this ring-to-ring transformation an initial formation of (unisolated) 1,2,4-oxadiazole-pyrimidinium salts, and subsequent ring-opening at the oxadiazole moiety occurs. Isolation of 2-(hydroxyamino)-pyrimidine from the reaction mixture evidenced the presence of a competing pathway where the N(4) nitrogen of the oxadiazole is involved in the formation of a regioisomeric pyrimidinium salt. The effect of the trifluoromethyl group on the product distribution is discussed.…
Nitrogen uptake and nitrogen fertilizer recovery in old and modern wheat genotypes grown in the presence or absence of interspecific competition
2015
Choosing genotypes with a high capacity for taking up nitrogen (N) from the soil and the ability to efficiently compete with weeds for this nutrient is essential to increasing the sustainability of cropping systems that are less dependent on auxiliary inputs. This research aimed to verify whether differences exist in N uptake and N fertilizer recovery capacity among wheat genotypes and, if so, whether these differences are related to a different competitive ability against weeds of wheat genotypes. To this end, 12 genotypes, varying widely in morphological traits and year of release, were grown in the presence or absence of interspecific competition (using Avena sativa L. as a surrogate wee…
Humus forms, carbon stock and properties of soil organic matter in forests formed on dry mineral soils in Latvia
2020
Over the last decades, more attention has been paid to carbon accumulation in soil, more recently, to soil humus forms, as they indicate environmental conditions and state of soil organic matter. There is insufficient information on the impact of soil and forest type on the chemical properties of soil, soil organic matter and humus form. Knowledge about the chemical properties of humus is crucial for modelling C and N accumulation and storage in forest soils. On this account, the aim of this study was to characterize soil humus forms, humus chemical properties and C stock and to determine the spatial distribution correlations between soil humus forms in forests formed on dry mineral soils. …
Reconstruction of human subsistence and husbandry strategies from the Iberian Early Neolithic: A stable isotope approach
2018
Objectives The Early Neolithic involved an important social and economic shift that can be tested not only with the material culture, but also through biomolecular approaches. The Iberian Peninsula presents few Early Neolithic sites where fauna and humans can be analyzed together from an isotopic perspective. Here we present an isotopic study on the site of Cueva de Chaves as an example for understanding the dietary and economical changes that took place during Early Neolithic in Iberia. Material and methods Here we apply carbon and nitrogen stable isotope analysis to bone collagen from 4 humans and 64 faunal samples from 14 different species. The large dataset belongs to the same unique ch…
Molecular and agronomic responses to soil inoculation with plant-growth promoting rhizobacteria and arbuscular mycorrhizae in Triticum durum
2012
Plant-growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal (AM) fungi contribute to plant nutrient uptake by increasing the availability of nutrients and the root adsorbing surface. However, the molecular mechanisms of plant responses to these associations are still under-investigated. Gene expression analysis could lead to the identification of biomarkers usable to early select genotypes for an increased nutrient uptake efficiency. The main objective of this study was to determine the effects of these associations on plant total biomass and grain yield in durum wheat (cv. Anco Marzio). Secondly, we aimed to analyze the expression pattern of key genes involved in nutrient uptake…
Soil and Plant Nitrogen Pools as Related to Plant Diversity in an Experimental Grassland
2007
Increasing plant species richness decreases soil NO 3 - concentrations in experimental plant mixtures, but the role of particular plant functional groups has remained unclear. Most analyses have focused on particular times of the year or were restricted to NO 3 - . We tested whether plant species richness or particular plant functional groups affect the size of plant-available N pools in soil (KCl-extractable NO 3 - , dissolved inorganic N and organic N [DON] and total dissolved N [TDN] in soil solution) and N concentrations and pools in aboveground biomass. Furthermore, we assessed seasonal variations in the effects of plant species richness and plant functional groups. The experimental gr…
Chemical and isotopic characterization of the gases of Mount Etna (Italy)
1997
Abstract In the period 1990–1995, 43 samples of dissolved gases in groundwaters (wells, springs and drainage galleries) and 64 samples of free gases (fumaroles, bubbling and soil gases) from the Mount Etna area were collected and analysed. Isotopic analyses were also carried out of both the carbon of the CO 2 in free gases and dissolved inorganic carbon (DIC) in the waters. The chemical composition of the gases depends on the relative abundances of three interacting components. These are gases of (1) atmospheric origin enriched in O 2 and N 2 , present almost exclusively in dissolved gases, (2) deep origin enriched in CO 2 , prevalent in the majority of cases, and (3) more superficial origi…
Interaction between the deep fluids and the shallow groundwaters on Vulcano island (Italy)
2001
The aim of this work is to study the interactions processes between the fluids of deep origin and the shallow groundwaters of the Vulcano Porto area. During 1995, 13 well waters were sampled three times (May, July and November) and analysed for major and some minor elements (B, Br and NH4) and for dissolved gases. The close relationship of these waters with the deep magmatic source is highlighted by the composition of the dissolved gases. Furthermore, the areal distribution of dissolved species is controlled mainly by the gas fluxes from depth and by the presence of a deeper thermal aquifer. The distribution of major anomalies in the parameters measured in the groundwaters, in fact, overlap…
Spatial patterns of, and environmental controls on, soil properties at a riparianepaddock interface
2012
Abstract Riparian zones are prominent features of agricultural landscapes because they are the last point to intercept nutrients and sediments before they enter water bodies. We investigated the soil properties, nutrient dynamics and vegetation composition at the riparian–agriculture interface. Soil physicochemical and vegetation properties were spatially heterogeneous along the transition from the grazed paddock into the un-grazed and revegetated riparian zone. Soil C stocks varied considerably across the site, with values ranging from 2% in the paddock to 5% in the riparian zone. Using Bayesian model selection, a predictive model for total soil carbon was developed. By including soil mois…