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Impacts of additional aerial inputs of nitrogen to salt marsh and transitional habitats 2012


This report comes from a desk-based investigation of the literature and data on the impacts of aerial/atmospheric nitrogen (NOX and NH3), on salt marshes and other transitional habitats, recognizing that these habitats often also receive nutrients from aqueous sources/pathways.

The study set out to determine the most appropriate nitrogen critical load to apply to salt marshes within the accepted published defined range (20–30 kg N ha-1 yr-1). In addition, the study would also determine whether it is appropriate to consider critical levels of nitrogen in relation to impact assessments. The data considered are drawn from a wide range of north temperate salt marshes but with special emphasis on those in Great Britain and north-west Europe.

Salt marshes vary greatly in their geographical and geomorphological situations and in the influences of adjacent transitional habitats upon them. Thus assessments of the impact of nitrogen inputs above the defined critical loads really need to be considered on a marsh by marsh basis. There was insufficient time within this project to consider in detail the impacts of nitrogen at or above the critical levels, but it seems likely that the cumulative effects of these short-term impacts would, in general, be adequately covered by the application of the critical load approach.

During the research for this report it became clear that the whole question of the setting of critical load limits and the management of vegetation in the coastal sphere, particularly in relation to salt marshes, would benefit from further good quality information to improve the reliability of the interpretations and to implement more effectively the findings in practical nature management applied to specific situations. The report therefore concludes by presenting recommendations for further studies.

Resource type Publication

Topic category Environment

Reference date 2012··

Boorman, L.A. & Hazelden, J. 2012. Impacts of additional aerial inputs of nitrogen to salt marsh and transitional habitats. CCW Science Report No. 995, Countryside Council for Wales, Bangor, Wales.

This report was produced on behalf of the Inter-agency Air Pollution Group and published by the Countryside Council for Wales (now Natural Resources Wales). Natural Resources Wales has granted JNCC permission to make this report available through the Resource Hub.

Responsible organisation
Communications, JNCC pointOfContact

Limitations on public access No limitations

Use constraints Available under the Open Government Licence 3.0

Metadata date 2020·06·15

Metadata point of contact
Communications, JNCC

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