Impact case study database

Changing policy and regulation to protect sensitive ecosystems

Drawing on the full body of atmospheric nitrogen deposition research from Manchester Metropolitan and collaborators, Caporn was the first author for a Natural England-commissioned report, entitled ‘ Assessing the effects of small increments of atmospheric nitrogen deposition (above the critical load) on semi-natural habitats of conservation importance’ (NERC210, published 2016).This review, which highlights the underpinning body of work on the effects of nitrogen deposition on sensitive habitats, has directly influenced policy and regulatory change. For example, it directly informed changes to Natural Resources Wales (NRW) permitting guidelines for new intensive livestock units in Wales. Drawing directly on NERC210 and the research (e.g. reference [2]), NRW changed how it protects lower plant communities under the Industrial Emissions Directive (IED). Specifically, the new GN020 guidance reduced the thresholds used to assess applications for intensive livestock units from 4% of the EU Critical Load to 1% [A].

This move has provided a much-needed policy tool to help control the rapid expansion of intensive agricultural units in Wales, and offers increased protection for internationally rare and sensitive habitats, such as Wales’ ancient oak woodlands, which contain half of the world’s Western Atlantic sessile oak and many rare species of mosses, liverworts and lichens. The research also underpins the current development of ‘low emission zones’ around 560 of these sensitive sites in Wales, to be introduced through nitrogen emission measures under the post-CAP Sustainable Farm Scheme [B]. NRW’s Principal Adviser for Air Quality and Biodiversity says: “The new thresholds we have put in place are intended to support business activity, by discouraging inappropriate agricultural development in these zones of interest. This approach supports LPAs in their assessment of cumulative impact at a strategic level to support the development of sustainable agriculture and protect Welsh biodiversity” [B].

NRW recently concluded public consultation to map and apply “extremely strict controls” requiring detailed modelling near Special Areas of Conservation, Sites of Special Scientific Interest, and undesignated areas with nitrogen-sensitive species [A]. The modelling will assess N impacts from all agricultural developments (not just livestock units), highlighting the fact that GN020 is just a significant first step towards evidence-based biodiversity regulation in Wales.

Following Wales’ lead, Shropshire County Council also introduced the same threshold reductions in their application guidance [A]. In response to NERC210, the Environment Agency is conducting a full review of its regulatory approach to nitrogen deposition. The Senior Air Pollution Adviser at JNCC states: “The evidence review and its use in agency procedures will enhance protection of the most at risk areas of the 42,049 km ² of air pollution sensitive habitat receiving excess atmospheric nutrient nitrogen. This research will be used to encourage proposers of new and existing emission sources to employ best practice or even relocate their activity away from key conservation sites” [C]. The Institute of Air Quality Management (IAQM), a professional body for over 500 practising air quality specialists, recommends the same stricter threshold criteria to assess air quality impacts on designated nature conservation sites [D]. This guidance has been applied in nitrogen impact assessments for projects ranging from infrastructure development (e.g. the Wheelabrator Kemsley waste-to-energy facility) to air quality habitat regulation [D].

The underpinning research and NERC210 report led to changes in the Highways England Design Manual for Roads and Bridges (DMRB LA 105 Air Quality, published 2019). The guidance supports additional protection for sensitive habitats close to future proposed motorways and trunk roads in England. Developers must evaluate whether nitrogen deposition is likely to affect air quality significantly and hence, put sensitive plant communities at risk [E].

The JNCC Nitrogen Decision Framework uses a scoring mechanism to attribute poor site condition to N pollution. The tool enables agencies and planners to identify the likelihood of risk to habitat integrity from nitrogen deposition, using site-specific research data made available through the Air Pollution Information System (APIS). APIS integrated Manchester Metropolitan nitrogen data for 400 previously unknown sensitive sites in 2017. This online service is used by staff in UK conservation and regulatory agencies, industry, and local authorities to facilitate assessment of air pollutants on habitats and species. Almost 100,000 users access APIS each year and this number is growing [C,D]. The resource has reduced pressure on UK agency staff to provide technical nitrogen data; APIS provides trusted, best available evidence for air quality assessments. The JNCC Senior Air Pollution Advisor states: “Without MMU’s contribution, thousands of APIS users, hectares of habitat and pounds of public money would be at greater risk from nitrogen deposition and its effects on ecosystems” [C].

One of the first applications of the Nitrogen Decision Framework was for nitrogen deposition assessments in Ashdown Forest in the High Weald. Made famous as the setting for the ‘Winnie the Pooh’ children’s stories, this ancient forest has international protection because of its wildlife and, as one of the largest, contiguous areas (2,500ha) of rare heathland in Europe [C]. Use of the Framework led to a reduction in the number of proposed new-build homes in the area, from 14,101 properties to 11,456, alongside habitat creation to reduce nitrogen impacts [C,F].

Restoring peatlands: locking in carbon and commercial benefits for MPS

Peatlands cover just 3% of global land surface but store around 33% of soil carbon and twice as much carbon as all the world’s forests. Degraded peatlands are responsible for a disproportionate 5% of global anthropogenic carbon dioxide emissions. The Manchester Metropolitan research [5-7] underpins, and essentially provided, the ‘green light’ for landscape-scale Sphagnum-based peatland restoration. In particular, the research supported the use of novel, cultivated propagules and derivative methods. This restoration now helps to safeguard vast quantities of carbon stored in peat, and has driven spectacular commercial growth for Micropropagation Service Ltd (MPS), the UK’s sole supplier of Sphagnum propagules.

The Peak District is Europe’s most degraded peatland landscape, but also a premier area of blanket bog; the extensive restoration and protection work here has national and international significance, not least as a demonstrator site for novel restoration techniques, such as the use of Sphagnum propagule. Since 2010, the pioneering MoorLIFE and MoorLIFE2020 projects have invested EUR22,700,000 to restore peatland at landscape scale: MPS Sphagnum propagules have directly restored 3,134ha [G]. A core component of an integrated strategy involving stabilisation, rewetting and revegetation, the Sphagnum restoration plays a key role in protecting the integrity of 12,000ha (58.0%) of fragile Peak District active blanket bog [G]. Based on success in the Peak District, additional restoration with MPS Sphagnum has taken place in Yorkshire (462ha) [G], lowland Lancashire (through CARE-PEAT), the Shropshire Marches, and the East Anglian Fens [H].

The Peak District MPS Sphagnum restoration today delivers a direct carbon benefit (emissions prevented) of 14,040tCO₂e/year and secures approximately 3,000,000t stored carbon from future loss (equivalent to a forest over twice the size of Wales). By contributing to active blanket bog protection, the work indirectly safeguards a carbon sink function of 36,000tCO₂e/year and approximately 11,600,000t stored carbon (equivalent to 12.1% of the UK’s 351.1MtCO₂e emissions in 2019) [I,G]. The work also contributes to wildfire and flood prevention, and improves water quality [G].

In 2019, the restoration required 2,200,000 million Sphagnum plugs and involved 20,000 person-hours of planting, alongside a large project management effort, providing significant employment to the rural Peak District economy [H].

The rise in demand for Sphagnum for restoration has driven tremendous commercial impacts for MPS. The company’s product sales have skyrocketed from GBP35,000 in 2012 to over GBP1,000,000 million in 2019 (CAGR 61.4%). Staff headcount has increased three-fold and the company now exports product(s) to Germany (200,000 propagules ordered for 2021). Since 2015 the company has invested GBP1,000,000 in capital for growth and GBP600,000 in research and development (R&D) [H].

Establishing the feasibility of Sphagnum as the UK’s first ‘carbon crop’

In collaboration with Manchester Metropolitan, MPS and partners are working to develop and demonstrate Sphagnum as the UK’s first ‘carbon crop’ and suitable biomass for compost peat replacement. MPS has committed GBP107,000 in a GBP499,000 Innovate UK project to pioneer methods for large-scale farming for carbon sequestration into land, whilst enabling the UK to remove all peat from growing media by 2030 [H]. There is already demand for Sphagnum biomass, as MPS’ Managing Director confirms: “Melcourt Industries Ltd, the leading peat-free growing media company in the UK… are extremely keen to obtain commercial quantities of Sphagnum biomass as soon as possible. They would place orders for 20,000m³ immediately if it was available. Klasmann-Deilmann, a leading growing media company in Germany, are committed to reduce their peat use by 15% by 2025 (representing around 200,000 cubic meters of biomass) and believe that farmed Sphagnum is the best option” [H].