Preconditions for Including the Effects of Urease and Nitrification Inhibitors in Emission Inventories.

Urease and nitrification inhibitors can reduce ammonia and greenhouse gas emissions from fertilizers and manure but their effectiveness depends on the conditions under which they are used. Consequently, it is essential for the credibility of emission reductions reported in regulatory emission inventories that their effectiveness is assessed under real-world conditions and not just in the laboratory. Here, we specify the criteria we consider necessary before the effects of inhibitors are included in regulatory emission inventories.

Influence of key factors on ammonia and nitrous oxide emission factors for excreta deposited by livestock and land-applied manure.

Ammonia (NH) and nitrous oxide (NO) emissions from livestock manure management have a significant impact on air quality and climate change. There is an increasing urgency to improve our understanding of drivers influencing these emissions. We analysed the DATAMAN ("DATAbase for MANaging greenhouse gas and ammonia emissions factors") database to identify key factors influencing (i) NH emission factors (EFs) for cattle and swine manure applied to land and (ii) NO EFs for cattle and swine manure applied to land, and (iii) cattle urine, dung and sheep urine deposited during grazing.

Revisiting sampling duration to estimate NO emission factors for manure application and cattle excreta deposition for the UK and Ireland.

According to the available guidelines, good practices for calculating nitrous oxide (NO) emission factors (EFs) for livestock excreta and manure application include that sampling duration should be of at least one year after the nitrogen (N) application or deposition. However, the available experimental data suggest that in many cases most emissions are concentrated in the first months following N application. Therefore resources could be better deployed by measuring more intensively during a shorter period.

Does liming grasslands increase biomass productivity without causing detrimental impacts on net greenhouse gas emissions?

Soil acidification has negative impacts on grass biomass production and the potential of grasslands to mitigate greenhouse gas (GHG) emissions. Through a global review of research on liming of grasslands, the objective of this paper was to assess the impacts of liming on soil pH, grass biomass production and total net GHG exchange (nitrous oxide (NO), methane (CH) and net carbon dioxide (CO)). We collected 57 studies carried out at 88 sites and covering different countries and climatic zones.

Predicting field NO emissions from crop residues based on their biochemical composition: A meta-analytical approach.

Crop residue incorporation is a common practice to increase or restore organic matter stocks in agricultural soils. However, this practice often increases emissions of the powerful greenhouse gas nitrous oxide (NO). Previous meta-analyses have linked various biochemical properties of crop residues to NO emissions, but the relationships between these properties have been overlooked, hampering our ability to predict NO emissions from specific residues.

Ammonia and nitrous oxide emission factors for excreta deposited by livestock and land-applied manure.

Manure application to land and deposition of urine and dung by grazing animals are major sources of ammonia (NH ) and nitrous oxide (N O) emissions. Using data on NH and N O emissions following land-applied manures and excreta deposited during grazing, emission factors (EFs) disaggregated by climate zone were developed, and the effects of mitigation strategies were evaluated. The NH data represent emissions from cattle and swine manures in temperate wet climates, and the N O data include cattle, sheep, and swine manure emissions in temperate wet/dry and tropical wet/dry climates.

DATAMAN: A global database of nitrous oxide and ammonia emission factors for excreta deposited by livestock and land-applied manure.

Nitrous oxide (N O), ammonia (NH ), and methane (CH ) emissions from the manure management chain of livestock production systems are important contributors to greenhouse gases (GHGs) and NH emitted by human activities. Several studies have evaluated manure-related emissions and associated key variables at regional, national, or continental scales. However, there have been few studies focusing on the drivers of these emissions using a global dataset.

Electron beam-induced deposition of platinum from Pt(CO)Cl and Pt(CO)Br.

Two platinum precursors, Pt(CO)Cl and Pt(CO)Br, were designed for focused electron beam-induced deposition (FEBID) with the aim of producing platinum deposits of higher purity than those deposited from commercially available precursors. In this work, we present the first deposition experiments in a scanning electron microscope (SEM), wherein series of pillars were successfully grown from both precursors. The growth of the pillars was studied as a function of the electron dose and compared to deposits grown from the commercially available precursor MeCpPtMe.

Global Research Alliance N O chamber methodology guidelines: Recommendations for deployment and accounting for sources of variability.

Adequately estimating soil nitrous oxide (N O) emissions using static chambers is challenging due to the high spatial variability and episodic nature of these fluxes. We discuss how to design experiments using static chambers to better account for this variability and reduce the uncertainty of N O emission estimates. This paper is part of a series, each discussing different facets of N O chamber methodology.

Global Research Alliance N O chamber methodology guidelines: Design considerations.

Terrestrial ecosystems, both natural ecosystems and agroecosystems, generate greenhouse gases (GHGs). The chamber method is the most common method to quantify GHG fluxes from soil-plant systems and to better understand factors affecting their generation and mitigation. The objective of this study was to review and synthesize literature on chamber designs (non-flow-through, non-steady-state chamber) and associated factors that affect GHG nitrous oxide (N O) flux measurement when using chamber methods.

Predicting nitrous oxide emissions after the application of solid manure to grassland in the United Kingdom.

Nitrous oxide (N O) emission from agricultural soils represents a significant source of greenhouse gas to the atmosphere. We evaluated the suitability of a modified Soil and Water Assessment Tool (SWAT) model to estimate the N O flux from the application of solid manure at two grassland sites (North Wyke [NW] and Pwllpeiran [PW]) in the United Kingdom. The simulated N O emissions were validated against field observations measured in 2011 and 2012 for model calibration and validation, respectively.

Identifying and Rationalizing the Differing Surface Reactions of Low-Energy Electrons and Ions with an Organometallic Precursor.

Surface reactions of electrons and ions with physisorbed organometallic precursors are fundamental processes in focused electron and ion beam-induced deposition (FEBID and FIBID, respectively) of metal-containing nanostructures. Markedly different surface reactions occur upon exposure of nanometer-scale films of (η-Cp)Fe(CO)Re(CO) to low-energy electrons (500 eV) compared to argon ions (860 eV). Electron-induced surface reactions are initiated by electronic excitation and fragmentation of (η-Cp)Fe(CO)Re(CO), causing half of the CO ligands to desorb.

Dissociation of the FEBID precursor cis-Pt(CO)Cl driven by low-energy electrons.

In this study, we present experimental and theoretical results on dissociative electron attachment and dissociative ionisation for the potential FEBID precursor cis-Pt(CO)Cl. UHV surface studies have shown that high purity platinum deposits can be obtained from cis-Pt(CO)Cl. The efficiency and energetics of ligand removal through these processes are discussed and experimental appearance energies are compared to calculated thermochemical thresholds.

Design, Synthesis, and Evaluation of CFAuCNR Precursors for Focused Electron Beam-Induced Deposition of Gold.

The Au(I) complexes CFAuCNMe (1a) and CFAuCN Bu (1b) were investigated as Au(I) precursors for focused electron beam-induced deposition (FEBID) of metallic gold. Both 1a and 1b are sufficiently volatile for sublimation at 125 ± 1 mTorr in the temperature range of roughly 40-50 °C. Electron impact mass spectra of 1a-b show gold-containing ions resulting from fragmenting the CF group and the CNR ligand, whereas in negative chemical ionization of 1a-b, the major fragment results from dealkylation of the CNR ligand.

Gross N transformation rates and related NO emissions in Chinese and UK agricultural soils.

The properties of agricultural soils in various regions of the world are variable and can have a significant but poorly understood impact on soil nitrogen (N) transformations and nitrous oxide (NO) emissions. For this reason, we undertook a study of gross N transformations and related NO emissions in contrasting agricultural soils from China and the UK. Seven Chinese and three UK agricultural soils were collected for study using a N tracing approach.

Nitrogen use efficiency and nitrous oxide emissions from five UK fertilised grasslands.

Intensification of grasslands is necessary to meet the increasing demand of livestock products. The application of nitrogen (N) on grasslands affects the N balance therefore the nitrogen use efficiency (NUE). Emissions of nitrous oxide (NO) are produced due to N fertilisation and low NUE.

Modeling nitrous oxide emissions from digestate and slurry applied to three agricultural soils in the United Kingdom: Fluxes and emission factors.

Organic fertilizers, such as digestates and manure, are increasingly applied in agricultural systems because of the benefits they provide in terms of plant nutrients and soil quality. However, there are few investigations of NO emissions following digestate application to agricultural soils using process-based models. In this study, we modified the UK-DNDC model to include digestate applications to soils by adding digestate properties to the model and considering the effect of organic fertilizer pH.

Modeling nitrous oxide emissions from three United Kingdom farms following application of farmyard manure and green compost.

Organic fertilizers, such as manure and compost, are promising additions for synthetic fertilizers in order to increase soil fertility and crop yields. However, the organic fertilizers applied to soils may increase nitrous oxide (NO, a greenhouse gas) emissions due to their lower C/N ratios, and therefore potentially contribute to global warming. Very few studies have used process-based models to assess the environmental advantages and drawbacks of compost soil amendments compared to other field treatments.

The contribution of cattle urine and dung to nitrous oxide emissions: Quantification of country specific emission factors and implications for national inventories.

Urine patches and dung pats from grazing livestock create hotspots for production and emission of the greenhouse gas, nitrous oxide (NO), and represent a large proportion of total NO emissions in many national agricultural greenhouse gas inventories. As such, there is much interest in developing country specific NO emission factors (EFs) for excretal nitrogen (EF pasture, range and paddock) deposited during gazing. The aims of this study were to generate separate NO emissions data for cattle derived urine and dung, to provide an evidence base for the generation of a country specific EF for the UK from this nitrogen source.

Electron induced surface reactions of (η-CH)Fe(CO)Mn(CO), a potential heterobimetallic precursor for focused electron beam induced deposition (FEBID).

Electron-induced surface reactions of (η-CH)Fe(CO)Mn(CO) were explored in situ under ultra-high vacuum conditions using X-ray photoelectron spectroscopy and mass spectrometry. The initial step involves electron-stimulated decomposition of adsorbed (η-CH)Fe(CO)Mn(CO) molecules, accompanied by the desorption of an average of five CO ligands. A comparison with recent gas phase studies suggests that this precursor decomposition step occurs by a dissociative ionization (DI) process.

Low energy electron-induced decomposition of (η-Cp)Fe(CO)Mn(CO), a potential bimetallic precursor for focused electron beam induced deposition of alloy structures.

The production of alloyed nanostructures presents a unique problem in focused electron beam induced deposition (FEBID). Deposition of such structures has historically involved the mixing of two or more precursor gases in situ or via multiple channel gas injection systems, thereby making the production of precise, reproducible alloy compositions difficult. Promising recent efforts to address this problem have involved the use of multi-centred, heterometallic FEBID precursor species.

Nitrogen losses to the environment following food-based digestate and compost applications to agricultural land.

The anaerobic digestion of food waste for energy recovery produces a nutrient-rich digestate which is a valuable source of crop available nitrogen (N). As with any 'new' material being recycled to agricultural land it is important to develop best management practices that maximise crop available N supply, whilst minimising emissions to the environment. In this study, ammonia (NH) and nitrous oxide (NO) emissions to air and nitrate (NO) leaching losses to water following digestate, compost and livestock manure applications to agricultural land were measured at 3 sites in England and Wales.

Low energy electron-induced decomposition of (η-CH)Ru(CO)Br, a potential focused electron beam induced deposition precursor with a heteroleptic ligand set.

Here we describe in detail low energy electron induced fragmentation of a potential focused electron beam induced deposition (FEBID) precursor, π-allyl ruthenium tricarbonyl bromide, i.e. (η-CH)Ru(CO)Br, specially designed to allow comparison of the effect of different ligands on the efficiency of low energy electron induced fragmentation of FEBID precursors.

The role of low-energy electrons in focused electron beam induced deposition: four case studies of representative precursors.

Focused electron beam induced deposition (FEBID) is a single-step, direct-write nanofabrication technique capable of writing three-dimensional metal-containing nanoscale structures on surfaces using electron-induced reactions of organometallic precursors. Currently FEBID is, however, limited in resolution due to deposition outside the area of the primary electron beam and in metal purity due to incomplete precursor decomposition. Both limitations are likely in part caused by reactions of precursor molecules with low-energy (<100 eV) secondary electrons generated by interactions of the primary beam with the substrate.