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.

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.

Management and implications of using nitrification inhibitors to reduce nitrous oxide emissions from urine patches on grazed pasture soils - A review.

Livestock urine patches are the main source of nitrous oxide (NO) emissions in pastoral system, and nitrification inhibitors (NIs) have been widely investigated as a NO mitigation strategy. This study reviews the current understanding of the effect of NIs use on NO emissions from urine patches, including the factors that affect their efficacy, as well as the unintended consequences of NIs use. It brings together the fundamental aspects of targeted management of urine patches for reducing NO emissions involving inhibitors.

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.

Global Research Alliance N O chamber methodology guidelines: Flux calculations.

A critical step in determining soil-to-atmosphere nitrous oxide (N O) exchange using non-steady-state chambers is converting collected gas concentration versus time data to flux values using a flux calculation (FC) scheme. It is well documented that different FC schemes can produce different flux estimates for a given set of data. Available schemes differ in their theoretical basis, computational requirements, and performance in terms of both accuracy and precision.

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: Statistical considerations, emission factor calculation, and data reporting.

Static chambers are often used for measuring nitrous oxide (N O) fluxes from soils, but statistical analysis of chamber data is challenged by the inherently heterogeneous nature of N O fluxes. Because N O chamber measurements are commonly used to assess N O mitigation strategies or to determine country-specific emission factors (EFs) for calculating national greenhouse gas inventories, it is important that statistical analysis of the data is sound and that EFs are robustly estimated. This paper is one of a series of articles that provide guidance on different aspects of N O chamber methodologies.

Global Research Alliance N O chamber methodology guidelines: Introduction, with health and safety considerations.

Non-steady-state (NSS) chamber techniques have been used for decades to measure nitrous oxide (N O) fluxes from agricultural soils. These techniques are widely used because they are relatively inexpensive, easy to adopt, versatile, and adaptable to varying conditions. Much of our current understanding of the drivers of N O emissions is based on studies using NSS chambers.

Does Brachiaria humidicola and dicyandiamide reduce nitrous oxide and ammonia emissions from cattle urine patches in the subtropics?

Nitrous oxide (NO) emissions from pasture-based livestock systems represent 34% of Brazil's agricultural greenhouse gas emissions. The forage species Brachiaria humidicola is known for its biological nitrification inhibition (BNI) capacity and NO emissions reduction ability from urine patches under tropical conditions. However, there is little information about the effect of BNI on NO emission and ammonia (NH) volatilisation in the subtropics.

Policy and Practice Certainty for Effective Uptake of Diffuse Pollution Practices in A Light-Touch Regulated Country.

Although the link between agriculture and diffuse water pollution has been understood for decades, there is still a need to implement effective measures to address this issue. In countries with light-touch regulation, such as New Zealand and Australia, most efforts to promote environmental management practices have relied on voluntary initiatives such as participatory research and extension programmes; the success of which is largely dependent on farmers' willingness and ability to adopt these practices. Increased understanding of the factors influencing farmer decision-making in this area would aid the promotion of effective advisory services.

Impact of nitrogen compounds on fungal and bacterial contributions to codenitrification in a pasture soil.

Ruminant urine patches on grazed grassland are a significant source of agricultural nitrous oxide (NO) emissions. Of the many biotic and abiotic NO production mechanisms initiated following urine-urea deposition, codenitrification resulting in the formation of hybrid NO, is one of the least understood. Codenitrification forms hybrid NO via biotic N-nitrosation, co-metabolising organic and inorganic N compounds (N substrates) to produce NO.

The efficacy of Plantago lanceolata for mitigating nitrous oxide emissions from cattle urine patches.

Urine deposited by grazing animals is the main source of nitrous oxide (NO) emissions in New Zealand. Recent studies have suggested that certain pasture plants, for example plantain (Plantago lanceolata), can curb NO emissions from livestock systems. This study aimed to i) evaluate the potential of plantain for reducing NO emissions from cattle urine patches; ii) determine the effect of including plantain in animal diets on urine-N loading and its influence on NO emissions; and, iii) evaluate whether any effects on NO emissions reduction could be attributed to a 'urine' or a 'plant' effect.

Assessing the Impact of Non-Urea Ruminant Urine Nitrogen Compounds on Urine Patch Nitrous Oxide Emissions.

Urea, the dominant form of N in ruminant urine, degrades in soil to produce NO emissions. However, the fate of non-urea urine N compounds (NUNCs) in soil and their contribution to urine patch NO emissions remain unclear. This study evaluated five NUNCs: allantoin (10%), creatinine (3%), creatine (3%), uric acid (1%), and (hypo)xanthine (0.

Author Correction: Influence of soil moisture on codenitrification fluxes from a urea-affected pasture soil.

A correction has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Response to nitrogen addition reveals metabolic and ecological strategies of soil bacteria.

The nitrogen (N) cycle represents one of the most well-studied systems, yet the taxonomic diversity of the organisms that contribute to it is mostly unknown, or linked to poorly characterized microbial groups. While new information has allowed functional groups to be refined, they still rely on a priori knowledge of enzymes involved and the assumption of functional conservation, with little connection to the role the transformations, plays for specific organisms. Here, we use soil microcosms to test the impact of N deposition on prokaryotic communities.

Influence of soil moisture on codenitrification fluxes from a urea-affected pasture soil.

Intensively managed agricultural pastures contribute to NO and N fluxes resulting in detrimental environmental outcomes and poor N use efficiency, respectively. Besides nitrification, nitrifier-denitrification and heterotrophic denitrification, alternative pathways such as codenitrification also contribute to emissions under ruminant urine-affected soil. However, information on codenitrification is sparse.

Phylogenetic and functional potential links pH and NO emissions in pasture soils.

Denitrification is mediated by microbial, and physicochemical, processes leading to nitrogen loss via NO and N emissions. Soil pH regulates the reduction of NO to N, however, it can also affect microbial community composition and functional potential. Here we simultaneously test the link between pH, community composition, and the NO emission ratio (NO/(NO + NO + N)) in 13 temperate pasture soils.

High-Resolution Denitrification Kinetics in Pasture Soils Link N2O Emissions to pH, and Denitrification to C Mineralization.

Denitrification in pasture soils is mediated by microbial and physicochemical processes leading to nitrogen loss through the emission of N2O and N2. It is known that N2O reduction to N2 is impaired by low soil pH yet controversy remains as inconsistent use of soil pH measurement methods by researchers, and differences in analytical methods between studies, undermine direct comparison of results. In addition, the link between denitrification and N2O emissions in response to carbon (C) mineralization and pH in different pasture soils is still not well described.

Effects of climate change on the delivery of soil-mediated ecosystem services within the primary sector in temperate ecosystems: a review and New Zealand case study.

Future human well-being under climate change depends on the ongoing delivery of food, fibre and wood from the land-based primary sector. The ability to deliver these provisioning services depends on soil-based ecosystem services (e.g.