Establishing a Scottish Nitrogen Balance Sheet

Establishing a full nitrogen balance sheet will help us manage and control nitrogen losses in the Scottish environment. Nitrogen loss poses a significant environmental threat, however, it is worth considering that nitrous oxide emissions only represent a very small fraction of total nitrogen turnover. In establishing a nitrogen balance sheet, it will be important to quantify large uncertainties in the nitrogen cycle such as the input of biologically fixed nitrogen, and the losses of nitrogen from soils as dinitrogen gas by denitrification.

National scale assessment will be important, but some effort needs to be put into finer scale sub regional assessments, including examples of farm scale assessment where management decisions about nitrogen use are determined.

There is a strong argument for adopting targets based on UNEP and EU proposals to halve nitrogen loss by 2030. Targets could also consider improving nitrogen use efficiency by agricultural crops and livestock.

Information should be made as widely available as possible with materials to help explain to the wider public the underlying importance of managing the nitrogen problem.

Annual targets are important

It will be important for this exercise to support the development and implementation of activities that , reduce nitrogen losses to the environment. It is unclear from the target section what targets are being proposed and what activities might be recommended in order to achieve any proposed targets. It would be helpful if the strategy could explore farm management opportunities to increase nitrogen use efficiency and reduce losses. There are many management interventions that could help achieve this ( e.g. the wider use of legumes in farming systems) that should be explicitly developed within this proposal. Reporting over a period of time could then demonstrate improvements in nitrogen use efficiency, and wider environmental protection. This would link to policy objectives in terms of biodiversity loss, climate change, water and air quality.