Modelling and mapping UK emissions of ammonia, methane and nitrous oxide from agriculture, nature, waste disposal and other miscellaneous sources for 2013

A contribution to the UK National Atmospheric Emission Inventory and Greenhouse Gas Inventory

Analysis of the impact to ammonia emissions of covers on slurry/digestate stores near nitrogen-sensitive protected habitats in England

This study investigated the potential impact of installing covers on slurry and digestate stores on ammonia emissions in England, both at a country scale and spatially targeting this measure near nitrogen-sensitive designated sites (SACs, SSSIs). The analysis was carried out in three steps: 1) Profiling each holding with cattle and/or pigs present to determine the probability of slurry storage, including store type, on the farm, using assumptions based on average practice by livestock sector (dairy, beef, pig) and herd size. 2) Quantifying emissions from slurry storage for each nitrogen-sensitive designated site, using the holding level probabilities from Step 1, for concentric zones of 1 km, 2 km, 5 km and 10 km. 3) Estimating the potential savings of emissions from covering all slurry stores for England as a whole and the spatial distribution of these potential benefits in relation to the location of sensitive designated sites. Natural crusting of slurry stores reduces ammonia emission by an average of 50%, whereas floating covers can reduce emissions by ca. 60% and rigid covers by ca/ 80%. Installing the most effective covers on all on-farm slurry stores (i.e. impermeable covers on above-ground tanks and permeable covers on lagoons) was estimated to reduce emissions from slurry stores by ~2.5 kt NH3. This would provide a saving of 36% in emissions associated with the storage of slurries in England overall (2019), from a current best estimate of 6.9 kt NH3. The largest savings are associated with the dairy sector (1.5 kt NH3, followed by 0.6 kt for pigs and 0.3 kt for beef cattle). Covering all suitable stores would therefore contribute towards achieving the targets of the NECR and objectives of the CAS and 25 Year Environment Plan, by reducing atmospheric emissions and their subsequent impacts on sensitive habitats and designated sites through elevated ammonia concentration and nitrogen deposition. It has been demonstrated that spatial targeting of ammonia reduction measures near designated sites gives higher returns for investment in mitigation than an even spread of the same effort across the country (e.g. Defra Project AC0109 , and JNCC/Defra project Nitrogen Futures ). The total predicted emission reductions from slurry covers within 1 km of all SACs and SSSIs are relatively small (compared to covering all slurry stores), at 183 t and 418 t NH3, respectively, or 366 t and 884 t NH3, for all suitable stores within 2 km of SACs and SSSIs, respectively. However, mitigation of intensive local “hot spot” point sources such as slurry stores by up to 80% (depending on the system in use) can reduce elevated atmospheric concentrations at nearby designated sites considerably. Therefore, if slurry covers were prioritised close to designated sites, i.e. using a spatially targeted approach, this could make a considerable difference to those sites. It should be noted that emission reductions at the storage stage of manure management result in a higher proportion of valuable nitrogen fertiliser being retained for land spreading to arable crops and grassland. If the slurry is then spread with low-emission techniques such as injection or trailing hose/trailing shoe, using best practice, this can result in savings due to less additional mineral nitrogen fertiliser being needed to achieve the same overall nitrogen input. If slurry stored under covers is spread using splash-plate technology, there is the potential for more ammonia being volatilised. However, this does not offset all savings from the installation of covers. If such measures were supported in, e.g., the Environmental Land Management Scheme under development, it would be important to clearly record the location of the measures (holding ID), the type of store and cover, and the volume and surface area of the store. By making such data available for use in the UK’s agricultural emission inventory, this would then enable crediting measures explicitly and ensuring that progress in emission reductions can be reported accurately. This is not only important for NECR targets, but also for enabling more accurate assessments and reporting of local emissions for quantifying the environmental benefits

The spatial distribution of ammonia, methane and nitrous oxide emissions from agriculture in the UK 2016

Annual Report to Defra (Project SCF0107), modelling and mapping UK ammonia and greenhouse gas emissions from agriculture. • Agricultural emissions of ammonia, methane and nitrous oxide for 2016 were spatially distributed across the UK, and maps produced. • Emission estimates produced for the 2016 inventory are based on a new emissions model developed by ADAS, Rothamsted Research and Cranfield University. The new emissions model replaces the previous NARSES and GHGI spreadsheets used to estimate emissions in the 2015 inventory and has been written in C#. • In parallel with the development of the new emission inventory model under Defra project SCF0102, the AENEID model, used to produce high-resolution maps of UK agricultural emissions, has also been updated. The new model version builds on techniques previously implemented in the AENEID model (e.g. Dragosits et al. 1998, Hellsten et al. 2008) and has been developed in the R statistical environment. It produces non-disclosive agricultural emission maps at a grid resolution of 1 km, compared with a 5 km grid resolution previously. The model incorporates detailed agricultural census data, landcover data (Rowland et al., 2017), agricultural practice information (e.g. fertiliser application rates, stocking densities) and emission source strength data from the UK emissions inventories for agriculture 2016 (Wakeling et al. 2018 and Brown et al. 2018). • All emission maps correspond to the totals reported by Rothamsted Research North Wyke (RResNW) for 2016

Ammonia emissions from UK non-agricultural sources in 2016: contribution to the National Atmospheric Emission Inventory

This report is part of the National Atmospheric Emissions Inventory (NAEI) and Greenhouse Gas Inventory (GHGI) project

The spatial distribution of ammonia, methane and nitrous oxide emissions from agriculture in the UK 2018

Annual Report to Defra (Project SCF0107). • Agricultural emissions of ammonia, methane and nitrous oxide for 2018 were spatially distributed across the UK, and maps produced. • Holding-level agricultural statistics on livestock numbers and crop areas for 2018 were not available in sufficient time for a full inventory model run. Therefore emission estimates produced for the 2018 inventory were derived by scaling the 2017 emissions based on the changes to 2018 in DA-level livestock numbers and crop areas. • Non-disclosive agricultural emission maps were produced at a grid resolution of 1 km by 1 km, using detailed agricultural census data, land cover data (Rowland et al., 2017), agricultural practice information (e.g. fertiliser application rates, stocking densities) and emission source strength data from the UK emissions inventories for agriculture 2017 (Misselbrook and Gilhespy 2020 and Brown et al. 2020). • All emission maps correspond to the totals reported by Rothamsted Research North Wyke (RResNW) for 2018

The influence of residential and workday population mobility on exposure to air pollution in the UK

Traditional approaches of quantifying population-level exposure to air pollution assume that concentrations of air pollutants at the residential address of the study population are representative for overall exposure. This introduces potential bias in the quantification of human health effects. Our study combines new UK Census data comprising information on workday population densities, with high spatio-temporal resolution air pollution concentration fields from the WRF-EMEP4UK atmospheric chemistry transport model, to derive more realistic estimates of population exposure to NO2, PM2.5 and O3. We explicitly allocated workday exposures for weekdays between 8:00 am and 6:00 pm. Our analyses covered all of the UK at 1 km spatial resolution. Taking workday location into account had the most pronounced impact on potential exposure to NO2, with an estimated 0.3 μg m−3 (equivalent to 2%) increase in population-weighted annual exposure to NO2 across the whole UK population. Population-weighted exposure to PM2.5 and O3 increased and decreased by 0.3%, respectively, reflecting the different atmospheric processes contributing to the spatio-temporal distributions of these pollutants. We also illustrate how our modelling approach can be utilised to quantify individual-level exposure variations due to modelled time-activity patterns for a number of virtual individuals living and working in different locations in three example cities. Changes in annual-mean estimates of NO2 exposure for these individuals were considerably higher than for the total UK population average when including their workday location. Conducting model-based evaluations as described here may contribute to improving representativeness in studies that use small, portable, automatic sensors to estimate personal exposure to air pollution

Ammonia emissions from UK non-agricultural sources in 2017: contribution to the National Atmospheric Emission Inventory

This report is part of the National Atmospheric Emissions Inventory (NAEI) and Greenhouse Gas Inventory (GHGI) project

AROMA - Agri-Environment Reduction Options for Mitigating Ammonia: assessment of the effects of RDPE environmental land management schemes on air quality

Measures available under agri-environment and grant schemes were assessed for their ammonia mitigation potential

Identification of potential “Remedies” for Air Pollution (nitrogen) Impacts on Designated Sites (RAPIDS)

Atmospheric nitrogen (N) deposition is a significant threat to semi-natural habitats and species in the UK, resulting in on-going erosion of habitat quality and declines in many species of high conservation value. The project focused on impacts and remedies for designated conservation sites, especially Natura 2000 sites protected under the EU Habitats Directive. However, the approach and certainly the measures could be equally applied to other areas of high conservation value. Evidence was drawn together to develop a framework for identifying key N threats at individual sites as a basis to target mitigation options in the context of potential legislative, voluntary and financial instruments