Nitrogen use efficiency in Scotland: annual report 2024

Future opportunities for improving nitrogen use efficiency in Scotland

In parallel to a programme of ongoing technical development and monitoring of the SNBS, the Scottish Government will also continue to explore opportunities to integrate new evidence provided by the SNBS into wider policy frameworks and structures.

Food Production: Agriculture

The next Climate Change Plan will include policies and proposals to ensure the agriculture sector plays its part in meeting our ambitious Net-Zero national target and we have commissioned research through the ClimateXChange to consider the potential to set a nitrogen use efficiency target for Scottish agriculture.

Food Production: Aquaculture

Our Vision for Sustainable Aquaculture, published in July 2023, includes outcomes related to climate change with an ambition to see the aquaculture sector play its part in Scotland achieving Net-Zero emissions by 2045, transitioning to a zero waste and circular economy and improving nitrogen use efficiency by reducing waste discharge, capturing more waste and exploring more opportunities for best use.

Transport

Among the most significant transport-related actions which will continue to play an important role in reducing nitrogen use is the introduction of Low Emission Zones (LEZ) that set minimum emission standards for vehicles entering the four cities of Glasgow, Edinburgh, Aberdeen and Dundee. Enforcement having commenced in Glasgow in 2023 with Aberdeen, Dundee and Edinburgh to follow in 2024. For diesel vehicles compliance with the LEZ standards requires the latest vehicle exhaust technologies to reduce nitrogen oxide (NOx) emissions in diesel engines work using an ammonia based solution to reduce harmful NOx emissions to nitrogen (N2).

Humans and settlements (including waste management)

Delivering a circular economy in Scotland is key to ensuring optimal, sustainable use of nitrogen inputs to the economy, for example by embedding sustainable production and consumption, reducing waste, maximising re-use and recycling of nitrogen, and minimising losses of nitrogen into the environment, including reducing nitrogen pollution from landfill leachate.

In January 2024, we published our draft Circular Economy & Waste Route Map for a second consultation, following a first consultation in 2022. Following analysis of the consultation feedback, the final Route Map will be published later in 2024. Alongside the Route Map, we introduced the Circular Economy (Scotland) Bill to the Scottish Parliament in June 2023. The Bill, which is currently on its passage through Parliament, contains provisions that require primary legislation to underpin Scotland’s transition to a circular economy, and modernise Scotland’s waste and recycling services.

Together the Route Map and Bill will provide the framework for delivering sustainable resource use (including nitrogen) and a more circular economy in Scotland across a range of sectors. This complements the existing, wide-ranging measures we have in place to support delivery of our objectives, as set out above, improving how efficiently nitrogen is used and supporting our drive to tackle climate change.

By reducing demand for new products and virgin materials and driving down the amount of material disposed of via landfill and energy from waste, a range of negative pollution impacts, including nitrogen, on biodiversity, air, bodies of water, and soils can be avoided. The Route Map’s Strategic Environmental Assessment (SEA) Report found that there was clear potential to reduce nitrogen pollution in Scotland via delivery of Route Map measures, for example as a result of a reduction in traffic congestion and reducing food waste.

As part of the draft Route Map’s wide ranging policy package, priority actions are set out to reduce food waste from all sources, building on our 2019 Food Waste Reduction Action Plan. We recognise that progress to reduce food waste has not been at the scale and speed required, partly as a consequence of Covid-19, and a collective reset of our approach to tackling food waste in Scotland is required. The package of measures is designed to address the whole food system; reset our approach to food waste; enhance our circular bioeconomy through adoption of regenerative land management practices; and ensure we have the data needed to understand and drive progress.

Forests, woodlands and terrestrial semi-natural ecosystems

Wood products are largely composed of carbon and contain relatively little nitrogen, compared with forest residues, including leaf litter and brash, which are generally retained in the forest where nutrients are naturally recycled. Despite this, to assure that high levels of nitrogen deposition will not pose challenges for Scotland’s sensitive near-natural woodlands, we will continue to monitor nitrogen flows in order to protect Scotland’s ecosystems.

SEPA and NatureScot in partnership UKCEH have developed web application that provides access to the latest modelled estimates of nitrogen deposition and ammonia concentrations at a designated site level. The data presented in the app will allow the Scottish agencies to work more collectively towards reducing the impacts of nitrogen on the environment and towards identifying areas that require specific attention, whether it’s towards promoting mitigation measures, monitoring impacts on our habitats or more direct action working with landowners to develop and implement local emission reduction measures to improve protection to sensitive habitats.