Assessing and Addressing Atmospheric Nitrogen Impacts on Natura 2000 Sites in Wales (AAANIS): project report

The aim of this work is to assist in developing an approach to address the impact of nitrogen deposition on Natura 2000 sites in Wales

Inventory of ammonia emissions from UK agriculture 2009

The National Ammonia Reduction Strategy Evaluation System (NARSES) model (spreadsheet version) was used to estimate ammonia (NH3) emissions from UK agriculture for the year 2009. Year-specific livestock numbers and fertiliser N use were added for 2009 and revised for previous years. The estimate for 2009 was 231.8 kt NH3, representing a 2.3 kt increase from the previously submitted estimate for 2008. Backward and forward projections using the 2009 model structure gave estimates of 317, 245 and 244 kt NH3 for the years 1990, 2010 and 2020, respectively. This inventory reports emission from livestock agriculture and from nitrogen fertilisers applied to agricultural land. There are a number of other minor sources reported as ‘agriculture’ in the total UK emission inventory, including horses not kept on agricultural holdings, emissions from composting and domestic fertiliser use

Site categorisation for nitrogen measures

Final report to Natural England on project IPENS-049

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

Nitrogen deposition in Northern Ireland and import/export of N deposition across the UK.

Atmospheric nitrogen (N) deposition represents a significant threat to sensitive habitats and species in the United Kingdom, with excessive N supply leading to declines in many important species of high conservation value, at the expense of fast-growing species that can exploit the additional nitrogen supply. Atmospheric N is produced from emissions of ammonia (NH3, mainly from agricultural sources) and nitrogen oxides (NOx, mainly from transport, industry, power generation and other combustion sources). This report aims to quantify and compare N deposition to land in NI from sources within NI and overseas (in the UK, Republic of Ireland, Shipping and the rest of Europe) to the amount of N deposition produced from NI sources that is deposited overseas. Estimating the likely source of N deposition received by NI will allow enable policy makers to assess how effective national N mitigation measures are likely to be. This study shows that Northern Ireland exports more atmospheric N deposition to the rest of the UK than it receives (from the UK and elsewhere). The amount of N originating from sources within NI and deposited within NI is mostly from NH3 emission sources (92%), with only 8% due to NOx emissions. These atmospheric N inputs produced within the country are the fraction that can be tackled with NI-internal policy development. When taking into account atmospheric N input from all sources (NI-internal and beyond), a substantial proportion of the NHx deposition is from sources within NI, while NOx deposition may be harder to tackle with a substantial proportion coming from the UK, Republic of Ireland and the rest of Europe, including shipping

2018 Estimates of nitrogen deposition in Northern Ireland and import/export of N deposition across the UK.

Atmospheric nitrogen (N) deposition represents a significant threat to sensitive habitats and species in the United Kingdom, with excessive N supply leading to declines in many important species of high conservation value, at the expense of fast-growing species that can exploit the additional nitrogen supply. Atmospheric N deposition originates from emissions of ammonia (NH3, mainly from agricultural sources) and nitrogen oxides (NOx, mainly from transport, industry, power generation and other combustion sources). This short report aims to update the import and export estimates of atmospheric nitrogen to/from Northern Ireland by Carnell et al. (2020). More up to date estimates of N deposition to/from Northern Ireland now exist for the emission year 2018, which were developed under the Air Pollution Information System (APIS http://www.apis.ac.uk/) project and funded by the UK government agencies (SEPA, SNH, JNCC, EA, NE, NRW, NIEA). This report aims to quantify and compare N deposition to land in NI from sources within NI and beyond (in the UK, Republic of Ireland, Shipping and mainland Europe) to the amount of N deposition produced from NI sources that is deposited to the rest of the UK. Estimating the likely source of N deposition received by NI will enable policy makers to assess how effective national N mitigation measures are likely to be

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

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