such organic layers may also promote the production of N₂O by denitrification. As anaerobic conditions prevail, significant production of CH₄ may also result, which could create landscape hot spots of GHG emissions (Davis and others, 2019). As the method focuses on promoting denitrification, it reduces landscape-level nitrogen use efficiency, reducing the potential for N, recovery.

<table><caption>**Table VI.7:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 7</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category <sup>a</sup></th><td>3</td><td>3</td><td>3</td><td>1</td><td>3</td><td>3</td></tr><tr><th>Magnitude of Effect</th><td>~</td><td>↑</td><td>↑</td><td>↓↓</td><td>↑↑</td><td>↑↑</td></tr></tbody></table>

### Landscape Measure 8: Drainage management

436. Drainage measures, such as insertion of tile drains (promoting run-off and avoiding waterlogging), and water table management, influence the oxygen status of soils (increasing oxygen availability), increasing lateral water transport and reducing residence times of nutrients. All these factors affect the efficiency of N, removal; for example, via denitrification (see Landscape Measures 5–7). The net consequence is that increasing drainage (such as through the use of tile drains) is expected to help abate emissions of N, compounds relating to denitrification (N₂O, N₂). In contrast, shorter residence times are likely to increase run-off of NO₃⁻ into stream waters. This measure can therefore only be considered as suitable where N₂O and N₂ abatement is considered a higher priority than nitrate pollution.

<table><caption>**Table VI.8:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 8</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>3</td><td>1</td><td>3</td><td>3</td><td>2</td><td>3</td></tr><tr><th>Magnitude of Effect</th><td>~</td><td>↓<sup>a</sup></td><td>↓</td><td>↑<sup>a</sup></td><td>↓</td><td>~?</td></tr></tbody></table>

### Landscape Measure 9: Stimulating N, removal in coastal waters

437. Streams and groundwater loaded with N, might directly reach the sea, specifically in agricultural regions close to coasts. It has been proposed that eel grass, seaweed growing, oyster farming or shellfish aquaculture are suitable for removing excess nutrients from coastal waters (Clements and Comeau, 2019; Kellogg and others, 2014) because nitrogen contained in phytoplankton is incorporated into biomass that is finally harvested, for example, as oysters, mussels or shellfish. However, reports on effects on N, removal

have been found to vary by orders of magnitude across sites, seasons and growing conditions (Kellogg and others, 2014). While the principle of encouraging N, recovery into useful products is sound, further evidence of the quantitative performance of this system is needed before increased confidence can be given to support its wider adoption to mitigate coastal water pollution.

<table><caption>**Table VI.9:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 9</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>3</td><td>3</td><td>3</td><td>2</td><td>2</td><td>2</td></tr><tr><th>Magnitude of Effect</th><td>~</td><td>~</td><td>~</td><td>↓</td><td>↓</td><td>↓?</td></tr></tbody></table>

## 3. Afforestation, set-aside and hedgerows as N, mitigation measures

438. Taking some parts of agricultural land out of production is an effective way to reduce all forms of direct N pollution from agriculture. In this approach, farmland may be converted to other types of land-uses that immobilize N, and hence reduce N, cascading at landscape scales. This has large local effects, and can be used for landscape planning, but will also have adverse indirect effects on the agricultural production in the target region. To maintain production, this might require the relocation of intensive agriculture production to other regions or other efficiency improvement measures. This mitigation approach applies, in particular, to low-productivity land, where the opportunities for N, and other landscape benefits easily outweigh the benefits of keeping the land in agricultural production.

### Landscape Measure 10: Introducing trees for afforestation and hedgerows in the landscape

439. Afforestation and the planting of hedgerows or strips of trees around agricultural fields can reduce NO₃⁻ leaching, and has very positive effects on biodiversity, for example, with regard to pollinators, or soil organic C stocks (Montoya and others, 2020; Thomas and Abbott, 2018; Holden and others, 2019; Ford and others, 2019). Preservation of existing woodland and hedgerow features will help avoid potential negative effects. However, the efficacy of hedgerows for N, retention will depend on: the size and placement of the hedgerows; the amount of NO₃⁻ in soil and groundwater; hydrological flow-paths and timing; and landscape biogeochemical conditions in top- and subsoils (Benhamou and others, 2013; Viaud and others, 2005). There is a risk that increased N, retention might go along with increased soil emissions of N₂O, although the net GHG balance is expected generally to favour reduced net emissions due to the increase in soil C stocks and perennial plant biomass (cf. Butterbach-Bahl and others, 2011). Hedgerows and forest edges also act as biofilters for nearby sources of NH₃ emissions (Kovář and others, 1996. See also Landscape Measure 12).

<footnote><sup>a</sup>The effects are compared with a reference where no technology is used and water moves directly to streams.</footnote>

<footnote><sup>a</sup>Reverse if drains are blocked!</footnote>
<table><caption>**Table VI.10:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 10</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>1</td><td>3</td><td>3</td><td>1</td><td>3</td><td>1</td></tr><tr><th>Magnitude of Effect</th><td>↓<sup>a</sup></td><td>↓↑<sup>a</sup></td><td>↓↑<sup>a</sup></td><td>↓↓</td><td>↑</td><td>↓↓</td></tr></tbody></table>

<sup>a</sup>The effects will depend on configuration in relation to Nr sources and sinks in a landscape. Increasing N sinks between an agricultural area and a stream provides an effective means to mitigate NO<sub>3</sub><sup>-</sup> losses. Substantial tree plantings are required to mitigate NH<sub>3</sub> emissions, unless close to point sources (Landscape Measure 12). Recapture of Nr emitted as NH<sub>3</sub> risks increasing soil losses of N<sub>2</sub>, NO<sub>x</sub> and NO<sub>3</sub><sup>-</sup>, unless surplus Nr is used in plant growth.

<figure><img src="image_177.png" /><figcaption>**Image 30:** Planting a steep-sided valley with trees (Landscape Measure 10) will simultaneously reduce nitrate run-off from surrounding agricultural land, reduce erosion and flooding, and capture atmospheric ammonia, while providing a haven for wildlife (photograph: © Archive of State Institution “Soil Protection Institute of Ukraine”, 2013).</figcaption></figure>

### Landscape measure 11: Set-aside and other unfertilized grassland

440. Unfertilized grasslands (for example, “set-aside” grassland), have the potential to remove NO<sub>3</sub><sup>-</sup> from lateral soil hydrological water flows and can be used as buffers to protect adjacent natural land or streams. The biomass could be harvested for fodder. Unfertilized grasslands also tend to have increased biodiversity compared to fertilized grasslands. If arable land is converted to non-fertilized grasslands, soil C stocks will increase. The measure is mainly targeted at reducing nitrate leaching when set-aside land is placed adjacent to watercourses. The effectiveness of the measure depends on whether overall N inputs are accordingly reduced in the landscape. With appropriate design, there is

also potential to reduce denitrification emissions to N<sub>2</sub>, but further assessment is needed to demonstrate this.

<table><caption>**Table VI.11:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 11</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category <sup>a</sup></th><td>3</td><td>2</td><td>2</td><td>1</td><td>2-3</td><td>1</td></tr><tr><th>Magnitude of Effect <sup>a</sup></th><td>~</td><td>~↓</td><td>~↓</td><td>↓↓</td><td>↓</td><td>↓↓</td></tr></tbody></table>

<sup>a</sup>The effectiveness of the measure is listed here on the assumption that adoption of set-aside implies a proportionate reduction of N inputs to the agricultural landscape. If N inputs are increased to maintain the same levels of agricultural production, then pollution trade-offs may occur (cf. Landscape Measure 10).

### 4. Mitigating Nr cascading from livestock hot spots

441. Livestock facilities, including housing, manure storage, or feeding and resting places of livestock kept outside are hot spots of environmental Nr pollution due to ammonia volatilization, N<sub>2</sub>O emissions and NO<sub>3</sub><sup>-</sup> leaching. This pattern can be exploited to mitigate the often very high point source losses from livestock facilities. Approaches include: the use of shelterbelts around large point sources; and smart relocation of livestock facilities and outdoor animals in a landscape; for example, away from sensitive natural areas such as natural conservation areas, streams, etc.

#### Landscape Measure 12: Shelterbelts around large point sources

442. Shelterbelts, such as woodland strips or set-aside land, can help to mitigate landscape Nr dispersion from emission hot spots, such as manure storage areas or animal housing facilities. This relies on the function of trees and hedges as biofilters for NH<sub>3</sub>, while also promoting dispersion, which reduces local concentrations (Theobald and others, 2001; Bealey and others, 2014). The approach also favours immobilization of Nr into plant biomass and soil organic N stocks (Valkama and others, 2019). Shelterbelts have been shown to significantly promote air NH<sub>3</sub> dispersion and recapture, while at the same time increasing soil C and N stocks, biodiversity etc. (Haddaway and others, 2018). Thus, shelterbelts can also reduce NO<sub>3</sub><sup>-</sup> leaching losses due to plant Nr uptake, and/or immobilization in soil organic N stocks. However, Nr immobilization of NH<sub>3</sub> and NO<sub>3</sub><sup>-</sup> may increase soil N<sub>2</sub>O emissions, although, given the observed increases in soil organic C stocks, the net GHG balance is likely to remain positive. This measure differs from Landscape Measure 10 in its function and effect. The focus here is on actions adjacent to point sources, where biodiversity may be adversely affected due to recapture of high ambient levels of Nr, which must be considered as part of the costs of this measure.

443. In the case of ammonia mitigation using trees, studies have shown that the architecture, placement and area of trees is critical to the success of the measure (for example,
Dragosits and others, 2006; Bealey and others, 2014). For example, a substantial body of trees is needed to allow significant recapture, as contrasted with simply an increase in dispersion. Studies have shown increased N₂O and NOₓ emissions from woodland soils in the vicinity of high NH₃ emissions from poultry farming, pointing to a trade-off (Skiba and others, 2006). Appropriate design of tree planting (for example, fast-growth species with high N uptake) may maximize the net benefits and minimize the trade-offs.

444. Given the trade-offs associated with use of shelterbelts and other woodlands as buffers to increase landscape resilience to the effects of nitrogen, it is important to recognize that the approach is not suitable in all contexts. For example:

(a) It is unlikely to be considered appropriate to use a woodland that is prioritized for nature conservation of oligotrophic plant species as a buffer for nitrogen pollution (for example, a site designated under the European Union Habitats Directive), since this would be expected to result in adverse effects on the protected habitat itself;

(b) It is more likely to be considered appropriate to plant a woodland on former agricultural land with the specific purpose of increasing buffering capacity and landscape resilience. Such a planted structure can be designed to help protect priority- designated natural habitats.

<table><caption>**Table VI.12: Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 12**</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>1</td><td>3</td><td>3</td><td>2</td><td>3</td><td>3</td></tr><tr><th>Magnitude of Effect</th><td>↓</td><td>↑<sup>a</sup></td><td>↑<sup>a</sup></td><td>↓↑<sup>a</sup></td><td>~?</td><td>↓↑?</td></tr></tbody></table>

### Landscape Measure 13: Environmentally smart placement of livestock facilities and outdoor animals

445. Livestock facilities, feeding and resting places of outdoor animals can be important point sources of NH₃ and NO₃⁻. Thus, such facilities should, as far as possible, be placed far from sensitive terrestrial habitats or water bodies (Panagopoulos and others, 2013). This can significantly reduce local N<sub>r</sub> problems, but might require the relocation or even the closure of existing facilities. The approach is most commonly used as part of planning procedures for new developments for proposals to expand existing farms. In particular, where legal requirements apply to protect natural areas (such as the Natura 2000 sites in the European Union), avoiding intensive farm developments in the near vicinity

may be one of the smartest approaches to avoid adverse effects on priority habitats. Simple online tools, such as the Simple Calculation of Atmospheric Impact Limits model<fnref n="34" />, can be used to support local decision-making (Theobald and others, 2009).

<table><caption>**Table VI.13: Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 13**</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>1</td><td>3</td><td>3</td><td>1</td><td>3</td><td>1</td></tr><tr><th>Magnitude of Effect</th><td>↓</td><td>~</td><td>~</td><td>↓</td><td>~</td><td>↓</td></tr></tbody></table>

## 5. Smart landscape farming

446. There is often a large potential to optimize the use of the natural resources at the landscape scale. This would deliver a better use efficiency of the nitrogen input (with a resulting general reduction in various types of losses), and a (geographically targeted) lower loss of N to the environment, especially where it has the highest vulnerability to particular types of N compounds.

### Landscape Measure 14: Digital planning of land-use on basis of a suitability assessment

447. Land-use and farm planning based on digital 3D precision maps of soil N<sub>r</sub> retention can help to optimize fertilizer use and reduce N leaching and other losses. For example, clay and carbon-rich soils have a higher N<sub>r</sub> retention capacity than sandy and carbon-poor soils, which may be used to inform fertilizer application rates.

448. In the same way, digital 2D precision maps of subsurface N<sub>r</sub> retention can also inform the optimization of fertilizer use, minimizing the impact on groundwater and/ or surface waters (Højbjerg and others, 2015). In addition, the reduction of NH₃ emissions from field operations (for example, slurry spreading) can be spatially and temporally targeted, thus increasing N<sub>r</sub> use efficiency through space and time. Optimization of land-use and land management (for example, placement of cropping areas and crop rotations in a landscape, introduction of shelterbelts or wetlands, etc.) can help to reduce N<sub>r</sub> cascading. In this way, it helps to improve nutrient retention at landscape scale, improve water quality in surface and groundwaters and reduce gaseous N<sub>r</sub> losses. However, land-use optimization does require an understanding of landscape fluxes. It typically needs to be supported through detailed modelling, which depends on a sound understanding of soils, groundwater and surface water flows, gaseous transfers through the soil/plant/atmosphere continuum, subsurface geological and geochemical characterization, and consideration of economic constraints (Nguyen and others, 2019; Todman and others, 2019).

<footnote>ᵃThe effects will depend on configuration in relation to N<sub>r</sub> sources and sinks in a landscape. Recapture of N<sub>r</sub> emitted as NH₃ from livestock farms by trees risks increasing soil losses of N₂, NOₓ and NO₃⁻, unless use of fast-growing trees ensures all surplus N<sub>r</sub> is taken up by the trees.</footnote>

<footnote n="34">³⁴ See www.scail.ceh.ac.uk/.</footnote>
<table><caption>**Table VI.14:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 14</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>2</td><td>2</td><td>2</td><td>2</td><td>2-3<sup>a</sup></td><td>2</td></tr><tr><th>Magnitude of Effect</th><td>↓</td><td>↓</td><td>↓</td><td>↓↓</td><td>↓</td><td>↓↓</td></tr></tbody></table>

## Landscape Measure 15: Towards mixed farming

449. Mixed farming combines livestock and cropping at farm and landscape scales. It provides opportunities to connect nitrogen inputs and surpluses, with the aim of reducing overall levels of nitrogen pollution and of increasing landscape-scale nitrogen use efficiency. The opposite can be illustrated by the situation where arable farming areas export grain to livestock farming areas, leading to excess manure in the livestock areas that cannot be used locally. Combining cropping and livestock locally can therefore help reduce pollution (for example, Key Action 10 in Sutton and others, 2013; Wilkins and others, 2008).

450. Significant synergies can be expected if mixed farming opportunities are combined with landscape planning (Landscape Measure 14). The goal is to achieve an optimized distribution of manure and fodder import/ production between fields and farms (Asai and others, 2018; Garrett and others, 2017). The planning and development of different types of farming will depend on special regional production opportunities or environmental targets for the local area. For example, crop production associated with high environmental N losses could be relocated and replaced by extensive low-input farming, if fields are close to nature protection zones. The reconnection of crop and livestock increases the overall landscape-level nitrogen use efficiency and has been demonstrated to reduce N surplus and water pollution (Garnier and others, 2016).

451. Mixed cropping-livestock systems also provide the opportunity to develop free-range livestock production in combination with crops that mitigate N losses (for example, trees, Landscape Measure 12). Conversely, there can also be a role for closed high-tech livestock housing systems, where input and outputs to the landscape compartments can be controlled. Since housed livestock systems are associated with much larger NH₃ emissions, the appropriate technical options to reduce emissions from housing, storage and manure utilization need to be incorporated, including consideration of options for N recovery (chapters IV and V).

<table><caption>**Table VI.15:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 14</caption><thead><tr><th>Nitrogen form</th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall N Loss</th></tr></thead><tbody><tr><th>UNECE Category</th><td>2</td><td>2</td><td>2-3<sup>a</sup></td><td>2</td><td>2-3<sup>a</sup></td><td>2</td></tr><tr><th>Magnitude of Effect</th><td>↓↓</td><td>↓↓</td><td>↓↓?</td><td>↓↓</td><td>↓↓?</td><td>↓↓</td></tr></tbody></table>

## Landscape Measure 16: Landscape-level targeting of technical options to reduce N losses

452. In chapters IV and V of the present guidance document, a wide range of technical options have been outlined, including the use of slow-release fertilizers, urea or nitrification inhibitors, acidification of manure, and manure injection in soils. Such measures are also useful at landscape levels, where they are targeted to be used in specific sensitive areas. For instance, more ambitious requirements (for example, requirements for very low-emission animal housing, manure storage and spreading) might be set in the immediate vicinity of wildlife areas, such as local nature reserves or internationally designated sites under the Convention on Wetlands of International Importance especially as Waterfowl Habitat. Planning the use of technical measures within a landscape context requires an understanding of the different

<figure><img src="image_178.png" /><figcaption>**Image 31:** Combination of nitrogen emission reduction techniques in a sensitive area (Landscape Measure 16). Here, covered manure storage (Manure Measure 1) is combined with use of a trailing-hose slurry spreader (Field Measure 6) (photograph © L'Albeitar, 2021).</figcaption></figure>

<footnote>a Further evidence is needed to demonstrate performance.</footnote>

<footnote>a Further evidence is needed to demonstrate performance.</footnote>
ecological priorities and their local, national and international legislative context. For example, in the European Union, a higher degree of legal protection is accorded to Special Areas of Conservation under the European Union Habitats Directive (requiring a precautionary approach), than may be required for a locally designated reserve (for example, where a balance of economic and environmental objectives may apply).

453. Analysis at the landscape scale can also allow for a more nuanced analysis of the potential trade-offs and synergies between emissions abatement and effects mitigation of different N compounds. For example, manure injection in soils or acidification of slurry can significantly reduce NH₃ volatilization, thus leaving more nitrogen in the soil, which can increase the risk of NO₃⁻ leaching and N₂O, NOₓ and N₂ emissions. Conversely, use of these measures may similarly increase plant nitrogen uptake efficiency, enabling a corresponding reduction of fresh N, inputs from fertilizers and biological nitrogen fixation. In this way, nitrogen use efficiency may be increased and N, losses decreased

when considered at the level of the landscape as a whole. Landscape application of technical measures allows these interactions to be considered (Theobald and others, 2004); for example, reducing NH₃ emissions will lead to less N deposition to forest and other nature areas (Dragosits and others, 2006), which, in turn, can be expected to reduce indirect NOₓ and N₂O emissions from these ecosystems (Cellier and others, 2011).

<table><caption>**Table VI.16:** Summary for each form of N loss of the UNECE category for effectiveness/practicality of implementation and magnitude of effect of Landscape Measure 16</caption><thead><tr><th></th><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall</th></tr></thead><tbody><tr><th>UNECE Category</th><td>2</td><td>2</td><td>3</td><td>2</td><td>3</td><td>2</td></tr><tr><th>Magnitude of Effect</th><td>↓↓</td><td>↓</td><td>↓?<sup>a</sup></td><td>↓↓</td><td>↓?<sup>a</sup></td><td>↓</td></tr></tbody><tfoot><tr><td colspan="7"><sup>a</sup>Less evidence is available for the benefits on NO<sub>x</sub> and N<sub>2</sub>, though corresponding effects to N<sub>2</sub>O can be expected.</td></tr></tfoot></table>

<table><caption>**Table VI.17:** Summary of land-use and landscape management measures and impacts on nitrogen losses</caption><thead><tr><th rowspan="2">Practice</th><th colspan="6">Effect</th><th rowspan="2">Principle</th></tr><tr><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall</th></tr></thead><tbody><tr><td colspan="8"><strong>Measures specific to crops and crop rotations:</strong></td></tr><tr><td>Landscape Measure 1: Increasing land cover with perennial crops</td><td>3</td><td>2</td><td>3</td><td>1</td><td>3</td><td>1</td><td rowspan="2">Permanent vegetation cover, highly productive, rapid immobilization of applied N, in soil organic matter and plant biomass.</td></tr><tr><td></td><td>~</td><td>↓↑</td><td>?</td><td>↓↓</td><td>↓↑</td><td>↓</td></tr><tr><td>Landscape Measure 2: Use of cover crops in arable rotations (use of "catch crops")</td><td>3</td><td>2</td><td>2</td><td>1</td><td>2</td><td>1</td><td rowspan="2">Fertilizer and manure applications should be adjusted to account for the N retained. N<sub>2</sub>O and NO<sub>x</sub> emissions may increase if cover crop is incorporated into the soil.</td></tr><tr><td></td><td>~</td><td>↓↑</td><td>↓↑</td><td>↓</td><td>↓~↑</td><td>↓</td></tr><tr><td>Landscape Measure 3: Inclusion of N<sub>2</sub>-fixing plants in crop rotations (including intercropping)</td><td>2</td><td>2(3)</td><td>3(3)</td><td>2(3)</td><td>3 (3)</td><td>2(3)</td><td rowspan="2">Reduce mineral N, use, organic N mineralization better in-line with plant N demand (Values in brackets reflect the effect of increasing soil N stocks).</td></tr><tr><td></td><td>~↓</td><td>↓(↑)</td><td>↓(↑)?</td><td>↓(↑)</td><td>~?</td><td>↓ (?)</td></tr><tr><td>Landscape Measure 4: Introducing agroforestry</td><td>1</td><td>3</td><td>3</td><td>1</td><td>3</td><td>1</td><td rowspan="2">Combination of annual and perennial crops, non-competitive exploration of rooting zone, increased N removal per area.</td></tr><tr><td></td><td>↓</td><td>~↑</td><td>~↑</td><td>↓↑</td><td>~?</td><td>↓</td></tr><tr><td colspan="8"><strong>Measures specific to management of riparian areas and waters:</strong></td></tr><tr><td>Landscape Measure 5: Constructed wetlands for stimulating N, removal</td><td>3(3)</td><td>3(3)</td><td>3(3)</td><td>1</td><td>3(3)</td><td>3(3)</td><td rowspan="2">Stimulation of N, removal via denitrification (Values in brackets compare with a reference system of advanced water processing with nutrient recovery).</td></tr><tr><td></td><td>~?</td><td>↑?(↑)</td><td>~?</td><td>↓↓(~)</td><td>↑(↑↑)</td><td>↓(↑↑)</td></tr><tr><td>Landscape Measure 6: Planting of paludal cultures in riparian areas or constructed wetlands</td><td>3(3)</td><td>1(3)</td><td>2(3)</td><td>1(3)</td><td>1(3)</td><td>2(3)</td><td rowspan="2">N, - fixation in biomass, which can be harvested (Values in brackets compare with a reference system of advanced nutrient processing and recovery).</td></tr><tr><td></td><td>~(~?)</td><td>↓(↑)</td><td>↓(↑)</td><td>↓(↑)</td><td>↓(↑)</td><td>↓(↑)</td></tr><tr><td>Landscape Measure 7: Use of organic layers to promote nitrate removal</td><td>3</td><td>3</td><td>3</td><td>1</td><td>3</td><td>3</td><td rowspan="2">Deliberate increase of denitrification reduces nitrate loss to water courses (but wastes N, resources)</td></tr><tr><td></td><td>~</td><td>↑</td><td>↑</td><td>↓↓</td><td>↑↑</td><td>↑↑</td></tr></tbody></table>
<table><thead><tr><th rowspan="2">Practice</th><th colspan="6">Effect</th><th rowspan="2">Overall</th><th rowspan="2">Principle</th></tr><tr><th>NH<sub>3</sub></th><th>N<sub>2</sub>O</th><th>NO<sub>x</sub></th><th>NO<sub>3</sub><sup>-</sup></th><th>N<sub>2</sub></th><th>Overall</th></tr></thead><tbody><tr><td rowspan="2">Landscape Measure 8: Drainage management</td><td>3</td><td>1</td><td>3</td><td>3</td><td>2</td><td>3</td><td></td><td rowspan="2">Aeration of soils, which hampers denitrification but facilitates N leaching (*Reverse if drains are blocked!).</td></tr><tr><td>~</td><td>↓*</td><td>↓</td><td>↑*</td><td>↓</td><td>~?</td><td></td></tr><tr><td rowspan="2">Landscape Measure 9: Stimulating N<sub>r</sub> removal in coastal water</td><td>3</td><td>3</td><td>3</td><td>2</td><td>2</td><td>2</td><td></td><td rowspan="2">Activities to recover N<sub>r</sub> in harvests; for example, planting of eelgrass, growing of seaweed, cultivating and harvesting mussels.</td></tr><tr><td>~</td><td>~</td><td>~</td><td>↓</td><td>↓</td><td>↓?</td><td></td></tr><tr><td colspan="9"><strong>Afforestation, set-aside and hedgerows as N<sub>r</sub> mitigation measures:</strong></td></tr><tr><td rowspan="2">Landscape Measure 10: Introducing trees for afforestation and hedgerows in the landscape</td><td>1</td><td>3</td><td>3</td><td>1</td><td>3</td><td>1</td><td></td><td rowspan="2">Selected cutting, continuous forestry / tree management. Planting on steep slopes.</td></tr><tr><td>↓</td><td>↓↑</td><td>↓↑</td><td>↓↓</td><td>↑</td><td>↓↓</td><td></td></tr><tr><td rowspan="2">Landscape Measure 11: Set-aside and other unfertilized grasslands</td><td>3</td><td>2</td><td>2</td><td>1</td><td>2-3</td><td>1</td><td></td><td rowspan="2">Taking land out of production, might include biomass harvesting.</td></tr><tr><td>~</td><td>~↓</td><td>~↓</td><td>↓↓</td><td>↓</td><td>↓↓</td><td></td></tr><tr><td colspan="9"><strong>Mitigating N<sub>r</sub> cascading from livestock hot spots:</strong></td></tr><tr><td rowspan="2">Landscape Measure 12: Shelterbelts around large point sources</td><td>1</td><td>3</td><td>3</td><td>2</td><td>3</td><td>3</td><td></td><td rowspan="2">Captures ammonia. Disperses the remainder upwards (useful if an N sensitive ecosystem is nearby). Immobilizes N<sub>r</sub> in plant biomass.</td></tr><tr><td>↓</td><td>↑</td><td>↑</td><td>↓↑</td><td>~?</td><td>↓↑?</td><td></td></tr><tr><td rowspan="2">Landscape Measure 13: Environmental smart placement of livestock facilities and outdoor animals</td><td>1</td><td>3</td><td>3</td><td>1</td><td>3</td><td>1</td><td></td><td rowspan="2">Locating livestock facilities away from N<sub>r</sub> sensitive ecosystems reduces impact.</td></tr><tr><td>↓</td><td>~</td><td>~</td><td>↓</td><td>~</td><td>↓</td><td></td></tr><tr><td colspan="9"><strong>Smart landscape farming:</strong></td></tr><tr><td rowspan="2">Landscape Measure 14: Digital planning of land-use on basis of a suitability assessment</td><td>2</td><td>2</td><td>2</td><td>2</td><td>2-3</td><td>2</td><td></td><td rowspan="2">Fertilization loads depen-d on soil properties, parent material, crops, etc.; Placement of crops depends on landscape properties.</td></tr><tr><td>↓</td><td>↓</td><td>↓</td><td>↓↓</td><td>↓</td><td>↓↓</td><td></td></tr><tr><td rowspan="2">Landscape Measure 15: Towards mixed farming</td><td>2</td><td>2</td><td>2-3</td><td>2</td><td>2-3</td><td>2</td><td></td><td rowspan="2">Helps move to circular agronomy. Improved distribution of manures and fodder production.</td></tr><tr><td>↓↓</td><td>↓↓</td><td>↓↓?</td><td>↓↓</td><td>↓↓?</td><td>↓↓</td><td></td></tr><tr><td rowspan="2">Landscape Measure 16: Landscape-level targeting of technical options to reduce N<sub>r</sub> losses</td><td>2</td><td>2</td><td>3</td><td>2</td><td>3</td><td>2</td><td></td><td rowspan="2">Uses highly effective but high-cost techniques close to sensitive ecosystems.</td></tr><tr><td>↓↓</td><td>↓</td><td>↓?</td><td>↓↓</td><td>↓?</td><td>↓</td><td></td></tr></tbody></table>

Note: The summary contained in the table above includes the assessed magnitude of effect for the specific submeasures listed: up↑ down ↓ or little/no effect indicated by ~, and with double arrows for the largest effects. UNECE categories 1, 2, 3 are estimated. Unless specified, the reference is represented by "no action".

454. In summary, the reviewed land-use and landscape management measures are effective in reducing the overall N<sub>r</sub> pollution, and can help increase the effects of the measures reviewed in chapters IV and V, by targeting these measures in space and/or time. Landscape measures can be very effective in mitigating local effects of NO<sub>3</sub><sup>-</sup> and NH<sub>3</sub>. However, other types of N<sub>r</sub> losses and N<sub>r</sub> pollution outside of the landscape, must be closely evaluated when implementing end-of-pipe solutions to reach local reduction targets.

## H. Priorities for farmers and other practitioners

455. The top land-use and landscape management measures to be implemented in practice can be divided into two groups: those related to a geographically targeted land-use change; and those related to geographically adapted management practices.
456. Some of the top land-use change measures identified during the workshops organized by the European Commission Directorate-General for Environment and the Task Force on Reactive Nitrogen under the Convention on Long-range Transboundary Air Pollution in 2016 and 2019 included:

(a) Set-aside/grassland (with no addition of fertilizers);

(b) Establishment of riparian buffer strips, or biodiversity buffer strips around or within fields (the difference being the proximity to aquatic environment):

(i) Hedgerows and afforestation;

(ii) Changed crop rotation/perennial crops (for example, permanent grasslands);

(iii) Agroforestry;

(iv) Wetlands and watercourse restoration and/or constructed mini-wetlands.

457. In comparison, the suggested management options included geographically targeted implementation of measures such as:

(a) Soil tillage and conservation (for example, no tillage of organic soils);

(b) Drainage measures and controlled drainage;

(c) Grassland management;

(d) Placement of livestock production;

(e) Spatial (re)distribution of manure;

(f) Fertigation and installation of proper irrigation system for dry cultivated areas;

(g) Placement of biogas plants and biorefineries for biomass redistribution.

458. The increased number of farmers turning to practices commonly termed "regenerative agriculture" is recognized, with certain practices having the potential to reduce some N losses, including no-till, organic farming (avoiding manufactured inorganic fertilizers and focusing on biological nitrogen fixation) and activities designed to increase carbon sequestration, etc. Such methods require further assessment to quantify their performance for all forms of N loss.

459. National guidance may be available to consider the effects of such measures. In table VI.18, values from Eriksen and others (2014) are listed for some of the exemplified measures, including budget-economic versus welfare-economic costs (for example, the economic impacts for farming versus the wider economic impact for society). For farmers and other practitioners, the economic costs, and resulting possibilities for compensation for these costs, or payment for ecosystem services provided, will most often be the most important factor for the decision of whether or not to implement the proposed measures. This emphasises the importance of economic cost assessments such as those exemplified in table VI.18, both in relation to the production costs for farmers, and the wider welfare-economic costs relevant to policymakers. Further action is needed on how to monitor the success of measures at a landscape level.

460. In accordance with the general guiding principles, a recommendation for the implementation of efficient land-

use and landscape management practices amongst farmers and other practitioners involves the same steps as for the policymakers (see table VI.17). It is recommended that, in addition to assessing the economic costs, each farm should calculate the environmental benefits at farm or landscape level. Such "green accounts" should itemize estimated effects of the measures implemented and report key data about the measures implemented and their efficacy. These data could be collected in a central database, to provide impact assessments for whole landscapes, watersheds, etc., and their specific targets for N reductions.

461. For example, according to the regulations in some UNECE countries, specific N leaching reduction targets are set for each watershed, based on model results or real measurements. In one system, operating in Denmark, farmers within a watershed can voluntarily choose to take actions (for example, whether to plant cover crops), and get financial incentives to meet targets set for the whole watershed each specific year. The alternative is that the farmers will have an obligatory commitment to plant cover crops, until the overall target is met. A geographically targeted and more cost-efficient regulation is thereby implemented.

## I. Summary of conclusions and recommendations

462. Overall recommendations are summarized in box VI.2. These recommendations are in line with earlier studies, such as the European Nitrogen Assessment chapter on N flows and fate in rural landscapes (Cellier and others, 2011), and include the following key points and needs for development of new approaches:

(a) The mitigation of N pollution at landscape scale requires consideration of interactions between natural and anthropogenic processes, including farm and other land management;

(b) The complex nature and spatial extent of rural landscapes means that experimental assessment of reactive N flows at this scale is difficult and often incomplete, but should include measurement of N flows in the different compartments of the environment, as well as comprehensive data sets on the environment (soils, hydrology, land-use, etc.) and on farm management.

463. Modelling is the preferred tool for investigating the complex relationships between anthropogenic and natural processes at landscape scale. Verification by measurements is also required, and simple measurements such as NO₃⁻ concentrations in streams should be considered. It must be recognized that there is a significant time lag between implementation of a control measure and response in stream-water NO₃⁻ concentrations. However, to date, only the NitroScape model – which was first developed for virtual landscapes (Duretz and others, 2011, under the NitroEurope integrated project) and only recently
<table><caption>Table VI.18: Summary of land-use and landscape management measures and impacts on nitrogen losses</caption><thead><tr><td>Measure</td><td>Comment</td><td>Annual N-effect (kg N/ha)</td><td>Budget-economic cost (EUR/kg N)</td><td>Welfare-economic cost (EUR/kg N)</td></tr></thead><tbody><tr><td>Set-aside</td><td>On rotational land</td><td>50</td><td>4–25</td><td>5–34</td></tr><tr><td>Riparian Buffer Strips</td><td>From rotation to permanent grass</td><td>37–74</td><td>6–12</td><td>8–16</td></tr><tr><td>Afforestation</td><td>On rotational land</td><td>50</td><td>7–20</td><td>9–27</td></tr><tr><td>Mini-wetlands</td><td>Surface run-off</td><td>5–20</td><td>3–23</td><td>4–31</td></tr></tbody></table>

Note: Examples on generalized effects in the form of reduction in N-leaching from the root zone and the related budget- and welfare-economic costs (for example, the economic impacts for farming versus the wider economic impact for society) according to Eriksen and others (2014). Other N effects in relation to nature and climate, and side effects from phosphorus, pesticides are also listed by these authors, but not shown here.

Box VI.2: Summarizing principles and recommendations for land-use and landscape management N mitigation based on multi-actor discussion.

Landscape scale N budgeting, which accounts for the main N flows, integrates all N sources and sinks over space and time, therefore providing the foundations to mobilize a more integrated N assessment to target appropriate measures.

A spatially targeted N budget approach is needed to better manage the N resource and operate within N limits for a defined area.

N budgeting is especially relevant in cases of stable conditions over time (for example, when farming systems are not under transition), and in relation to annual N accounts. In addition, shorter-term and longer-term assessments of N dynamics are important.

Landscape topography and soil properties are important factors controlling the fate of N at landscape scales, and the integration of 3D soil and geology maps is important in understanding N flows and mitigation options, in particular in relation to N leaching.

Landscape assessment includes evaluation of both sources and sinks, for example, both hot spots for emission and input/ reception of N in the ecosystems, including effects in sensitive areas and water bodies and effects of atmospheric N pollution on terrestrial habitats.

A certain amount of N release does not have the same effect at all places in the landscape. This means that landscape measures offer the opportunity to optimize the effects of landscape properties and heterogeneity in relation to N flows and impacts.

The processes for N loss consist of non-linear interactions, are threshold-dependent and are interlinked with acute stressors. Treating these stressors in isolation or in a simplified additive manner may cause pollution swapping and thereby underestimate future N-related risks, including eutrophication, acidification and changes in forests and other terrestrial ecosystems, as well as water systems functions and diversity.

A combination of several N mitigation measures is needed to reach multiple sustainable development objectives present in whole landscapes. These need to be ranked in order of importance, as the mitigation of some N flow pathways is more important than others, according to context.

Both the local and global effects of direct N emissions within the landscape, and indirect N emissions induced inside and outside of the landscape, should be included when assessing the impacts of the N mitigation measures.

Landscape-scale measures provide the opportunity for increased retention and sequestration of N in space and time, and thereby the opportunity for increased N harvest and nutrient recovery, optimizing manure redistribution and reducing impact on the aquatic environment, while promoting the bioeconomy.

The operational unit and the related economic benefits and/or trade-offs are important for the effective implementation of landscape scale measures, and vary from farm to farm and from the farm to the landscape scale and beyond (for example, watershed, local and regional scales). Legal frameworks may support optimal implementation. The application of new tools tailored to landscapes is needed to assist the implementation of landscape-scale measures. These can also support strengthening of cultural and natural infrastructures for a more sustainable nitrogen use.
applied to real landscapes (for example, Franqueville and others, 2018, under the French Escapade project) – has integrated all the components of landscape scale N flows: farm functioning; short-range atmospheric transfer; and hydrology and ecosystem modelling. Consequently, the further development and testing of such models is highly recommended, together with their integration into new landscape assessment and decision-support tools.

464. In conclusion, both from an environmental and a socioeconomic perspective, it is important to include landscape management and land-use measures in the mitigation of N pollution. The present chapter recommends a two-step guidance procedure for the implementation of N mitigation measures, and lists selected top measures relevant for policymakers, farmers and other practitioners.

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# Chapter VII: Development of packages of measures for integrated sustainable nitrogen management

Lead author: Mark A. Sutton

Contributing authors: Tom Misselbrook, Cláudia M. d. S. Cordovil, Patrick Durand and Oene Oenema

## A. Introduction

465. The material presented in this guidance document provides the basis for improving understanding of the connections across the nitrogen (N) cycle, together with a menu of options. Reflection on the listed principles (chapter III) can inform national and regional approaches based on understanding the key issues. Together, the descriptions of measures for the different parts (chapters IV-VI) indicate the benefits and limitations of the actions.

466. While consideration of the overall nitrogen flow through the agrifood system is a key element of bringing these parts together, there is also a need to visualize these connections more fully. The present chapter therefore examines selected case studies to illustrate possible "packages of measures". These represent coherent groups of measures according to the locality, farming system and environmental context. The examples may be useful to Governments, agencies, businesses and community groups as they consider how to fit together the different measures and principles.

467. At the heart of the approach is consideration of the N flow in the context of the nitrogen cycle. Nitrogen inputs for fertilizer and feed are directly connected to N outputs in crops and livestock for food and wasteful losses to the environment. This means that decisions by all actors have an effect on system efficiency, amounts of N wasted and levels of pollution. Measures taken earlier in the nitrogen chain therefore need to be followed up by complementary measures later in the chain if the full benefit is to be achieved. For example, measures to reduce NH₃ emissions from animal housing should be matched with actions for manure storage and land application, if earlier savings are not to be lost.

468. Inspection of the different measures listed in chapters IV-VI quickly shows how they are complementary – addressing different parts of the system. This means that it is essential to consider “packages of measures” as part of integrated sustainable nitrogen management, both to realize synergies between measures and to minimize trade-offs.

469. The following examples illustrate how packages of measures are needed:

(a) Ammonia emissions tend to occur quickly (hours-days), so measures that minimize contact of ammonium-rich resources with air (principle 15) are essential;

(b) Measures that reduce a large nitrogen loss (for example, NO₃⁻, N₂ and NH₃) leave more Nₐ in the farming system. It is therefore essential to reduce additional Nₐ inputs (or increase outputs/storage) if the full benefits of

the measures are to be realized in increasing nitrogen use efficiency (NUE) and reducing N losses (principle 6);

(c) Emissions of N₂O, NO and N₂ to air and leaching of NO₃⁻ and other Nₐ compounds to water tend to occur as a result of surplus ammonium and nitrate in soils, where these exceed plant needs. Therefore, reducing these emissions depends on knowing the amount and timing of plant N uptake (principle 7) in order to avoid soil N surplus;

(d) The different processes controlling oxidized Nₐ losses (N₂O, NO, NO₃⁻) versus NH₃ emissions mean that measures for the first group are not necessarily helpful for the second (and vice versa). Measures must therefore be considered together;

(e) According to mass balance, all measures that allow an appropriate reduction in total Nₐ inputs, while maintaining productivity, will increase system-wide NUE and lead to a reduction in all Nₐ losses (principle 7);

(f) Wider land-use and landscape management strategies complement animal and crop abatement strategies by offering the opportunity to increase landscape resilience, mitigating environmental effects by managing temporal and spatial distribution (principles 11 and 15). This means that land-use/landscape measures are especially relevant to reduced local adverse impacts (for example, effects on nature and water).

470. Further issues of this kind are detailed in chapter III. The case studies here show how this thinking may be applied to design coherent packages of measures. The focus here is on agricultural examples, although the philosophy is relevant for all source sectors.

## B. Case studies

### Case Study 1: Measures package for an intensively managed dairy farm

471. Intensive dairy production typically includes both housed animals and animals grazing for part of the year. This means that measures will need to consider both systems. In this case study, a broad approach is taken with the objective of the illustrative measures package being to:

(a) Reduce total N losses to maximize Nₐ retention in the farming system, and reduce denitrification losses to N₂, while offering financial benefit by reducing the need for bought-in manufactured fertilizers;

(b) Reduce, as a priority, NH₃ emissions, given close
location to certain protected natural habitats;

(c) Follow good practice to minimize nitrate leaching and avoid N pollution of watercourses according to basic national guidelines;

(d) Reduce N₂O and NOx emissions, so long as this is consistent with other measures.

472. The context of this case study is a rural country with low vehicular NOx emissions, but with high tropospheric ozone concentrations, so any reductions in soil NOx will be considered a significant benefit. The location has a mild climate, where it may be possible to increase the grazing season from that currently implemented. The soils are impermeable, with low risk of NO₃⁻ leaching, but have a high risk of surface run-off to vulnerable watercourses. The farm buildings have natural ventilation, with cattle on slatted floors over a slurry pit. There is no possibility of investment to alter significantly the housing design, though targeted modifications may be feasible. The farm is grass-based, with insignificant arable area. Manure is currently surface broadcast on grassland using a traditional vacuum spreader (splash plate).

473. The following issues are worth considering related to grassland N flows:

(a) With impacts of ammonia being relevant, an increase in the grazing season (Field Measure 18) provides an obvious opportunity to reduce NH₃ emissions. However, special measures would be needed to ensure that this does not exacerbate N lateral run-off to nearby watercourses. This could be managed by using landscape features such as wooded buffer zones (Landscape Measure 10);

(b) While the impermeable soil means that nitrate leaching to groundwater may not be a priority in the case study, this soil type is also vulnerable to increased denitrification, wasting N, resources as N₂ and increasing N₂O emissions;

(c) If winter rainfall is high, poor drainage in the impermeable soils risks “poaching” of the grassland by cattle, where grass is destroyed by trampling and fields become muddy. Such poaching damage reduces plant nutrient uptake and can increase N₂O and N₂. This may be a key limiting factor for extending the grazing season in this case study.

474. With these considerations, a possible package of measures for emissions related to grazing animals in this case study could be:

(a) An increase in the time animals spend grazing (Field Measure 18), for example, by extending the grazing season by one to two weeks at each end, while recognizing the limits to maintain a healthy soil and sward and using appropriate grazing. This can contribute to reducing total NH₃ emissions from the farm;

(b) Ensuring healthy sward development and avoid “poaching” by active herd management through rotational grazing. This minimizes the risk of surplus N not being taken up by plants, helping to reduce N₂O and N₂ losses. It will also help to reduce any nitrate leaching to the extent that this occurs;

(c) Ensuring that there is appropriate fencing to restrict

grazing within recommended distances of watercourses (Field Measure 19), and consider use of growing vegetation in buffer areas near streams (Landscape Measure 10). This can contribute to reducing run-off of N, into streams;

(d) Working with a local research partner to test application of nitrification inhibitors to urine patches (Field Measure 20) (for example, by use of drones or as part of grazing rotation management).

475. The following issues are worth considering in relation to emissions from housing and manure management:

(a) The diet of each animal group during the winter housing period should be reviewed to see if there are opportunities for the total mixed ration to be optimized in relation to protein needs, as minimizing unnecessary excess may offer opportunities to reduce wasteful nitrogen excretion (Dietary Measure 1);

(b) The existing slatted floor system is not well suited to immediate segregation of urine and faeces (Housing Measure 1). With realistically available finance in this case study, substantial redesign of the building is not feasible;

(c) Add-on measures may be feasible if targeted funding can be obtained that does not require major rebuilding of the animal house;

(d) Liquid manure (slurry) is currently stored in an open tank, liable to significant NH₃ emissions.

476. With these considerations in mind, a possible package of measures to reduce N emissions from the animal housing and manure management could consist of:

(a) Targeting the protein content of the housed diet of the cattle to match requirement, for example, 15-16 per cent crude protein for dairy cows on average. Consider phase-feeding according to animal age if cows are block calved or kept in age groups to give even more precision, while ensuring that energy needs are also met. Start regular testing of the forage component of the diet (for example, stored farm silage) as it is used, to help achieve the target crude-protein intake (Dietary Measure 1);

(b) Exploring options for grants for low-emission housing, storage and manure spreading, especially given the priority that the farm is near a protected natural habitat sensitive to ammonia;

(c) Installing an automatic system for washing of animal house floors (on a twice-daily basis) (Housing Measure 3);

(d) Installing a system to acidify slurry in the slurry pit (Housing Measure 7). This system will reduce NH₃ emissions from the housing itself, as well as having further benefits to reduce emissions during manure storage and spreading;

(e) Upgrading the vacuum spreader to include a trailing hose or trailing shoe system (Field Measure 6). This will further reduce NH₃ emissions in addition to the benefit of slurry acidification and also ensure accurate spreading of manure to enabling consistent delivery (and fertilization benefits for crops), while minimizing the spreading of slurry near vulnerable habitats (Landscape Measure 16). Consultation with nature agencies and use of online models (for example, http://www.scail.ceh.ac.uk) may be needed to agree minimum distances between slurry spreading and sensitive nature areas).
477. The overall package of field and housing measures should be reviewed in relation to local goals for nitrogen saving, emission reduction of different N<sub>r</sub> forms and ecosystem protection. Use of an integrated nutrient management plan (Field Measure 1) informed by soil nutrient testing, combined with the low-emission measures identified, will help to reduce bought-in fertilizer inputs to save money and realize the benefit of the emissions reductions (principle 6). Monitoring of the farm-level N balance may prove a useful indicator to work out how fast to reduce purchased N inputs as part of improving farm level NUE and reducing N surplus. Further measures may be included if higher ambition is needed (for example, covering of slurry store, installing solid surfaces for animal holding and traffic areas).

**Case Study 2: Measures package for an organic dairy farm**

478. It is relevant to consider how the preceding case study might be different if the context were an organic dairy farm at the same location. The following general considerations should be noted:

(a) It is assumed that the environmental objectives for sustainable nitrogen management are the same as in the previous case study. The major differences are that manufactured inorganic fertilizers will not be used, nor will strong acids be purchased to acidify slurry (for example, sulphuric acid);

(b) On this organic farm, nitrogen inputs are provided by using clover-rich swards, which generate a sufficiently protein-rich ration for winter feeding of cattle during the winter housing period. Preliminary estimates for this case study show that it is still relatively intensive, with high milk production, although N inputs are 30 per cent lower than in Case Study 1, with half the overall nitrogen surplus, but these estimates need to be checked;

(c) As a livestock farm, production of liquid manure (slurry), emissions of NH<sub>3</sub> from animal housing will still be significant, including from the open manure storage and surface broadcast application of slurry to surrounding grass fields. Ammonia emissions from this organic farm and from the field application still pose a significant risk to adjacent protected natural habitats;

(d) Although no inorganic fertilizers are used, the activities still contribute significantly to N<sub>2</sub>O, NO and N<sub>2</sub> emissions, especially following field application of liquid manure. Nitrate and other N<sub>r</sub> run-off are similarly a concern;

(e) As there are no bought-in N sources to the farm in this organic system, the farmer is strongly motivated to reduce N losses to maximize the benefit of the limited N resources that are available.

479. All of the measures described in Case Study 1 would be available except for the following:

(a) Acidification of slurry (Housing Measure 7);

(b) (Chemical) nitrification inhibitors during grazing (Field Measure 20).

475 bis. To take account of the fact that some measures are not available in this organic context, the following package of measures may be considered:

(a) Extension of grazing season (Field Measure 18) – as per Case Study 1;

(b) Rotational grazing to avoid poaching – as per Case Study 1;

(c) Avoidance of grazing of sensitive areas near watercourses (Field Measure 19) and identify buffer areas (Landscape Measure 10) – as per Case Study 1;

(d) Working with local research partner to test application of a nitrification inhibitor to urine patches (Field Measure 20) – as per Case Study 1, but testing the use of an organic nitrification inhibitor, such as neem oil;

(e) Testing opportunities to fine-tune diet in relation to protein needs with a target crude protein content and consider the possibility of phase feeding (Dietary Measure 1) – as per Case Study 1;

(f) Exploring options for grants for low-emission housing, storage and manure spreading, given the priority that the farm is near a protected habitat sensitive to ammonia – as per Case Study 1, but opportunity for grants may be greater given the organic farm commitment of Case Study 2;

(g) Installing an automatic system for washing of animal house floors (Housing Measure 3) – as per Case Study 1;

(h) Undertaking work with a research partner to test a biotrickling system for capturing and recovering NH<sub>3</sub> from the slurry pit as an organic N resource (cf. Housing Measures 7 and 15), which reduces emissions from housing and manure storage;

(i) Investigating low-cost options for covering slurry stored outside the animal house. Consider whether natural crusting is feasible (Manure Measure 2) or whether it is possible to store manure with a solid cover (Manure Measure 1);

(j) Upgrading the vacuum spreader to include a trailing shoe system (Field Measure 6) – as per Case Study 1 – but with larger emission reductions than trailing hose and even better suited to grassland. This is especially important because no acidifying agent has been used in this organic farming case study;

(k) Minimizing the spreading of slurry near vulnerable habitats (Landscape Measure 16) – as per Case Study 1.

480. As with Case Study 1, the overall package should be reviewed in relation to local goals for nitrogen saving, emission reduction of different N<sub>r</sub> forms and ecosystem protection. Use of an integrated nutrient management plan (Field Measure 1) informed by soil nutrient testing will be especially important to maximize efficient use of the limited available N resources, and to realize the benefit of savings through the emissions reductions (principle 6). Additional measures may be included if higher ambition is sought (for example: Field Measure 7 – manure injection; Manure Measure 8 – local manure acidification and nitrogen enrichment augmented by wind/solar energy).

**Case Study 3: Measures package for production of Mediterranean processing tomato**

481. Production of the processing tomato (Lycopersicum esculentum L) is among the most important in the
Mediterranean region (four Mediterranean countries are among the top 10 producers globally). It is a perennial crop, grown annually by transplanting seedlings at the beginning of spring and growing until the end of summer. This results in a superficial and widely spread root system that requires heavy irrigation and fertilization, especially with nitrogen. The measures package illustrated in this case study consists of a broad approach with the following objectives:

(a) Reduction of total N losses to maximize N<sub>r</sub> retention in the cropping system, focusing in particular on the reduction of NO<sub>3</sub><sup>-</sup> leaching losses, with soils located in vulnerable drainage basin areas;

(b) Reduction of N losses by surface run-off to vulnerable watercourses, given that irrigation is mostly done by drip systems on the soil surface;

(c) Reduction of soil N<sub>2</sub>O and NO<sub>x</sub> emissions, which are at risk of being substantial because of water availability and high temperatures. These nitrogen losses are also associated with the heavy tillage needed to prepare soil for tomato transplanting;

(d) Reduction and avoidance of possible increases in NH<sub>3</sub> emissions (if future markets increasingly favour urea-based fertilizer products);

(e) Reduction of the total amount and costs of bought-in fertilizer.

482. The context of tomato production in this case study is rural areas, where traffic is almost entirely restricted to agricultural vehicles. There are few NOₓ emissions from traffic sources in the case study area. This means that reductions in soil NOₓ will be considered a significant benefit for air quality. Manure is usually not currently used in this production system, which focuses on N and other nutrient inputs from manufactured inorganic fertilizers. Currently, the fertilizer formulations used in the case study are based on ammonium nitrate, augmented by other nutrients. Non-urea composite fertilizers are the most commonly used for basal dressing. This is followed by the application of diverse soluble compounds in fertigation, including urea solutions in the fertigation. The following issues should be considered in relation to N flows associated with production of processing tomato:

(a) The greatest risk of N loss relates to nitrate leaching to groundwater, due to the heavy irrigation demand for this crop in the Mediterranean climate. As irrigation is mostly done on the soil surface according to current practice, there is also potential for losses by run-off. An appropriate irrigation system and water management are necessary to ensure that irrigation does not exacerbate N leaching or surface run-off;

(b) The soil types are conducive to nitrate leaching to groundwater, with the farms of this case study located in vulnerable areas, which makes this loss a priority;

(c) Processing tomato is highly demanding for N fertilization, which results in farmers often applying more N fertilizer than is needed by the crop. Besides basal dressing with N and other nutrients, tomato fields are already "fertigated" (for example, fertilizer addition to irrigation water, Field Measure 16). The amounts of N added by fertigation are currently varied according to

the crop-growth cycle, but lack of calibration according to the actual performance of crops increases the risk of N loss, with farmers typically using more N than is needed as part of their risk management (for example, in case of unfavourable weather or nitrogen losses);

(d) Soil preparation for tomato cropping before seedling transplantation is substantial and involves deep tillage and several machine transits. This increases N emission as N<sub>2</sub>O and NO<sub>x</sub> from soil, as well as fuel combustion from agricultural machinery. Increased mineralization of soil organic matter (SOM) from tillage increases NH<sub>3</sub> emissions in variable amounts, though the exact amounts lost are not well known. Significant losses of N through denitrification to N<sub>2</sub> are expected but are not currently well-quantified.

483. With these considerations, a possible package of measures for emissions related to production of processing tomato in the field could consist of:

(a) Installation of more accurate irrigation systems compatible with the crop management. These can contribute to reducing total N losses from the field, including leaching and surface run-off (principle 16);

(b) Adoption of better-controlled systems for water management (principle 20). This also maximizes tomato growth and production, increasing plant uptake of N, which then helps to reduce total N losses (especially N leaching);

(c) Recognizing the different watering needs of tomato plants over the growing cycle according to the actual conditions as they develop. This requires variable irrigation flow and N addition by fertigation to match crop needs, based on updatable calculation of crop needs. This can also lead to water savings, as well as savings in N and other nutrient inputs. This measure may be supported by computer estimates, updated in real time based on meteorological data and monitoring of crop-growth indicators;

(d) Ensuring that there is appropriate soil coverage with impervious sheeting to reduce evapotranspiration water losses. This can contribute to reducing the irrigation flow needed and thus losses of N<sub>r</sub> into surface water and groundwater bodies. When using black sheeting, weed growth will be reduced to minimum, which will also help avoid pesticide use. Consideration should be given to plastic reuse and recycling;

(e) More carefully fine-tuning the amounts of N added during basal fertilization and fertigation, avoiding overapplication of nutrients (including N), as informed by soil nutrient testing and crop performance indicators (for example, leaf colour sensing). This can significantly reduce nitrate leaching and other N emissions depending on the extent of fertilizer overapplication in current practice (principle 5; Field Measures 2, 3, 4 and 16). Use of electronic tools to calculate feasible cost-savings by fine-tuning N inputs to match requirements may help mobilize change;

(f) Reducing the intensity of soil tillage for tomato bedding preparation can also contribute to reducing N emissions derived both from fuel combustion and from soil itself. Alternative solutions include planting the seedlings
in mulched non-tilled soil, to reduce weed growth, the use of sheeting and the need for tillage;

(g) Including an awareness campaign targeting farmers in the case study area to highlight the risks of unabated urea use for NH₃ emissions. This should raise awareness among farmers of the likely N losses by emission from urea-based fertilizers, the economic value of N losses and the environmental consequences. This awareness can then be used to mobilize adoption of additional measures (for example, inclusion of a urease inhibitor, Field Measure 13).

484. This list of field measures should be considered in relation to local conditions and local goals for nitrogen saving, emission reductions of different N<sub>r</sub> forms, human health and ecosystem protection. Using a nutrient management plan supported by soil testing is beneficial to optimization of the use of fertilizers, saving of money and reduction of pollution (Field Measure 1). Further measures may be included if higher ambition is needed to meet agreed goals (for example, actions related to soil preparation prior to seedling transplanting).

### C. Considerations for developing packages of measures

485. It is for users of this guidance to develop their own case studies, informed by the principles and measures presented herein. The following is a summary of key points to consider when developing packages of measures for integrated sustainable nitrogen management:

(a) **Consider which are the priority nitrogen threats** being managed in the area/country of concern (for example, air pollution, water pollution, climate change, biodiversity) and whether there are particular local risks (for example, designated sensitive nature areas or water bodies);

(b) **Consider whether there are other priority issues** that need to be considered at the same time concerning element flows (for example, carbon, phosphorus, sulphur) and other threats (for example, water scarcity);

(c) **Consider the level of ambition relevant for the situation**, for example, in relation to local or international commitments to reduce emissions and impacts;

(d) **Consider which principles are most applicable for the situation** (chapter III) according to the emission sources, local and regional context and priority nitrogen forms;

(e) **Identify relevant measures** needed to address the different nitrogen forms according to context and the relevant issues faced (drawing on chapters IV–VI).

486. Based on these actions, a draft package of measures may be proposed. This should be reviewed to consider what it might achieve for abatement of emissions to air and losses to water of different nitrogen forms. The following questions are relevant concerning each proposed package of measures:

(a) Does the package cover all important **nitrogen forms** according to agreed targets and priorities?;

(b) Are the measures in the package **complementary in achieving the overall goals**, for example, in relation to control of multiple nitrogen forms, and consistent with the principles of overall nitrogen flow?;

(c) What would the **overall outcome of the package** be, in terms of emissions reduction to air and losses to water, and is it sufficiently ambitious to meet agreed goals?;

(d) What would the **overall amount of nitrogen saved** from the measures package be that would otherwise have been wasted to air and water pollution and denitrification to N<sub>2</sub>?;

(e) **By how much is wasted nitrogen to the environment reduced** compared with unabated practice? How does it compare with the Colombo Declaration ambition to “halve nitrogen waste” by 2030 (considering the sum of all loss pathways of N<sub>r</sub> and N<sub>2</sub> emission)?<fnref n="35" />

(f) What are the **initial implementation and running costs** of the package of measures, and what is the potential for reducing these costs?;

(g) What are the **initial and running benefits** of the package of measures, including monetary value of nitrogen saved in moving towards a circular economy for nitrogen?;

(h) What are the **wider societal benefits** of the package of measures, including valuation of the multiple benefits to environment, economy, health and well-being in the wider context of sustainability?;

(i) What is the **relationship to the Sustainable Development Goals**? How many of the Goals does the measures package help achieve and in what way?

487. As illustrated in chapter VII, multi-actor review of proposed packages of measures can serve to fine-tune the approach, building consensus on the way forward, including the need to highlight opportunities (for example, cost savings, environmental improvement, sustainability of resources) and discuss potential barriers (for example, implementation costs, need for harmonization, regulatory tools and opportunity for investment to catalyse action).

488. The above shortlist does not address all issues. Rather, it is intended to help support countries by illustrating how the different principles and measures described in this guidance document can be fitted together. The next step is for countries, regions and local communities to start considering their own packages of measures.

489. It is anticipated that feedback will be gathered through activities under the Air Convention and in partnership with other international processes, especially through the developing Inter-convention Nitrogen Coordination Mechanism (INCOM). This feedback will be essential as guidance is further developed for other United Nations regions within the context of the International Nitrogen Management System (INMS), as well as to evaluate progress in relation to achieving the Sustainable Development Goals.

<footnote n="35">³⁵ See https://apps1.unep.org/resolution/?q=node/286.</footnote>
# Appendix I
## Further guidance

The following sources of information can provide further guidance:

**Ammonia:** Options for Ammonia Abatement: Guidance from the UNECE Task Force on Reactive Nitrogen. Available at http://www.clrtap-tfrn.org/content/options-ammonia-abatement-guidance-unece-task-force-reactive-nitrogen.

**Ammonia:** United Nations Economic Commission for Europe Framework Code for Good Agricultural Practice for Reducing Ammonia Emissions. Available at https://unece.org/environment-policy/publications/framework-code-good-agricultural-practice-reducing-ammonia.

**Nitrates and nutrient cycles:** Recommendations for establishing Action Programmes under Directive (2012) 91/676/EEC concerning the protection of waters against pollution caused by nitrates from agricultural sources. Available at https://ec.europa.eu/environment/water/water-nitrates/studies.html.

**Global Overview of Nutrient Management:** Our Nutrient World: The challenge to produce more food and energy with less pollution (see especially chapter 6: Practical options to reduce adverse effects by improving nutrient use). Available at http://nora.nerc.ac.uk/id/eprint/500700/1/N500700BK.pdf.

**Region-specific leaflets on best practices:** "Resource efficiency in Practice – Closing Mineral Cycles". Examples from: Brittany (France) [EN, FR], central Denmark [EN, DK], Lombardy (Italy) [EN, IT], Murcia (Spain) [EN, ES], North-Brabant (Netherlands) [EN, NL], southern and eastern Ireland [EN], Weser-Ems (Germany) [EN, DE], Wielkopolskie (Poland) [EN, PL]. Available at https://ec.europa.eu/environment/water/water-nitrates/studies.html including project report: https://ec.europa.eu/environment/water/water-nitrates/

pdf/Closing_mineral_cycles_final%20report.pdf (see p. 87 onwards).

**Baltic Sea Action Plan:** Helsinki Commission for Baltic Marine Environment Protection, HELCOM, Available at https://helcom.fi/baltic-sea-action-plan/. See pp. 86–96 for agricultural measures.

**European Union River Basin Management Plans:** including recommendations, Available at https://ec.europa.eu/environment/water/water-framework/impl_reports.htm.

**Climate change:** Mainstreaming climate change into rural development policy post 2013: Final report European Commission 2014. Available at https://www.ecologic.eu/sites/default/files/publication/2015/mainstreaming_climatechange_rdps_post2013_final.pdf (see table 3 therein for list of measures).

**Nitrogen use efficiency:** European Union Nitrogen Expert Panel (2015). Nitrogen Use Efficiency (NUE) - an Indicator for the Utilization of Nitrogen in Agriculture and Food Systems. Wageningen University, Netherlands. Available at http://www.eunep.com/reports/.

**Nitrogen use efficiency:** European Union Nitrogen Expert Panel (2016). Nitrogen Use Efficiency (NUE) - Guidance Document for Assessing NUE at Farm Level. Available at http://www.eunep.com/reports/.

**National fertilizer recommendations:** for example, UK RB209, available at https://ahdb.org.uk/nutrient-management-guide-rb209.

**National codes of good agricultural practice:** including national ammonia codes of good agricultural practice, as required for signatories to the Gothenburg Protocol.
**Appendix II**
**Glossary of key terms**<fnref n="36" />

**Abatement** – strategies or methods to reduce nitrogen losses to the environment, and thereby reduce the direct and indirect effects.

**Afforestation** – establishment of a forest or stand of trees in an area where there was no previous tree cover.

**Agroforestry** – cultivation and use of trees and shrubs with crops and livestock in agricultural systems.

**Ammonia stripping** – physicochemical process used to remove ammonia from sewage, slurry, wastewaters, etc.

**Anaerobic digestion** – series of biological processes in which microorganisms break down biodegradable material in the absence of oxygen.

**Anthropogenic processes** – processes derived from human activities, as opposed to those occurring in natural environments without human influence.

**Biobased fertilizer** – naturally occurring substances rich in nutrients, such as manure, urine, bird guano, compost.

**Biochar** – charcoal-like by-product of the process of pyrolysis, or the anaerobic thermal decomposition of organic materials.

**Biofilters** – a filter bed in which exhaust air or liquid is subjected to the action of microorganisms that assist in its decomposition.

**Biological nitrogen fixation** – a process in which N₂ from the atmosphere is converted into NH₃ and other Nₐ forms mediated by specialist bacteria.

**Biotrickling filters** – a combination of a biofilter and a bioscrubber. They work in a similar manner to biofilters, except that an aqueous phase is trickled over an inert packing. The trickling solution contains essential inorganic nutrients that are usually recycled.

**Carbon sequestration** – the capture and removal of carbon dioxide from the atmosphere and its storage in an alternative carbon-related reservoir; for example, soil organic matter, charcoal, tree growth.

**Catch crop** – fast-growing crop that is grown between successive plantings of a main crop, and helps to reduce N losses during fallow.

**Circular economy** – an economic system aimed at reusing and recycling resources (hence "circularity").

**Co-benefit** – a coincidental benefit that arises for a secondary issue as a result of addressing a primary issue (for example, employing a technique to mitigate pollution which is also more cost effective).

**Companion crop** – planting of different crops in proximity

for a number of different reasons, including pest control.

**Compost** – material resulting from the process of composting, an aerobic method of decomposing organic solid wastes.

**Constructed wetlands** – treatment systems that use natural processes involving wetland vegetation, soils and their associated microbial communities to treat wastewater.

**Crop rotations** – the practice of growing different types of crops in the same area over several growing seasons.

**Deep-injection** – The application of liquid manure or digestate by placement in deep, vertical slots, typically about 150 mm deep, cut into the soil by specially designed tines.

**Deep-litter** – an animal housing system, based on the repeated spreading of bedding material in indoor or outdoor contexts.

**Denitrification** – the reduction of nitrate (NO₃⁻) to dinitrogen (N₂). Nitrous oxide (N₂O) may be produced as an intermediary, depending on conditions.

**Dietary Measures** – measures consisting of changes in the type, amount and quality of animal feed or human food.

**Drainage management** – practice that allows farmers to have more control over drainage, by using a water control structure drain to bring the drainage outlet to various depths.

**Drip irrigation** – a type of crop irrigation involving the controlled delivery of water directly to individual plants through a network of tubes or pipes.

**Dung** – animal faeces.

**ECE** – Economic Commission for Europe, one of the five regional commissions under the jurisdiction of the United Nations Economic and Social Council: includes Europe, Eastern Europe, the Caucasus, Central Asia and North America.

**Ecosystem services** – the benefits people obtain from ecosystems. These include: provisioning services, such as food and water; regulating services, such as flood and disease control; cultural services, such as spiritual, recreational and cultural benefits; and supporting services, such as nutrient cycling, that maintain the conditions for life on Earth.

**Emissions abatement** – technology applied, or measure taken, to reduce emissions and its impacts on the environment.

**Enteric methane** – methane that is produced in the first stomach (rumen) of ruminants. Ruminants are mammals that acquire nutrients from microbially mediated enteric

<footnote n="36">³⁶ This glossary draws in part on the RAMIRAN *Glossary of terms on livestock and manure management*. Recycling Agricultural, Municipal and Industrial in Agriculture Network (eds. B. Pain and H. Menzi), 2011.</footnote>
fermentation of their food, such as cows and sheep.

**Eutrophication** – the enrichment of the nutrient load in ecosystems (terrestrial and aquatic), especially compounds of nitrogen and/or phosphorus.

**Ex ante assessment** – evaluation of the potential success of an operation before it occurs.

**Ex post assessment** – evaluation of an operation after it has occurred.

**Exceedance** – The amount of pollution above a "critical level" or "critical load". It may be expressed in different ways, such as accumulated area of exceedance.

**Faeces** – dung, solid fraction of animal excreta.

**Fertigation** – addition of water-soluble products into irrigation systems, with the purpose of fertilizing.

**Housed livestock** – animal breeding systems involving animals being kept in different housing types.

**Hydrolysis** – chemical decomposition in which a compound is split into other compounds by reacting with water.

**Immobilization** – the conversion of nutrients in the soil into an inaccessible or immobile state. The opposite process is mineralization, in which decomposition releases nutrients, which are then accessible to plants.

**Inorganic fertilizers** – manufactured inorganic and organo-mineral fertilizers, often referred to as "synthetic" fertilizers. This includes all mineral N fertilizer types such as ammonium nitrate and ammonium sulfate, and also urea (and urea-based fertilizers).

**Integrated** – combining or coordinating separate elements to provide a harmonious, interrelated whole process.

**Intercropping** – farming method that involves planting or growing more than one crop at the same time and on the same piece of land.

**Leaching** – the washing out of soluble ions and compounds by water draining through soil.

**Legumes** – a group of plants, many of which are able to extract N₂ from the atmosphere using specialized "nodules" that contain symbiotic nitrogen-fixing bacteria.

**Litter** – excreta mixed with variable portions of bedding material. The term can also refer to decomposed fallen plant material (for example, leaf litter).

**Manure** – organic materials used as fertilizer in agriculture. Animal manure is composed of faeces and may contain bedding material and urine (when it may be referred to as "farmyard manure"). "Green manure" is a crop grown with the aim of being incorporated into the soil.

**Manure management** – collection, storage, treatment and utilization of animal manures in an environmentally sustainable manner.

**Manure processing** – processes to transform a variety of manure types and sources into value-added products. This includes forming them into pellets.

**Manure treatment** – a range of different processes that can be applied to manure and may add value. Examples include concentrating nutrients, odour reduction and volume reduction.

**Mineralization** – the decomposition of organic matter, releasing the nutrients in soluble inorganic forms that are then available to plants (the opposite of "immobilization").

**Mini-wetlands** – constructed wetlands with biofilters used to reduce nitrogen and phosphorus emissions from field drains to aquatic environments.

**Mitigation of nitrogen** – reducing the adverse effect of any N, compound, such as the atmospheric pollutants NH₃ and NOₓ, the aquatic pollutant NO₃⁻, or the greenhouse gas N₂O.

**Mixed farming** – type of farming that involves the growing of a variety of crops (for example, annual, multiannual and permanent crops) and livestock breeding.

**Multi-actor** – group of partners with complementary types of knowledge – scientific, practical and other. They join forces in project activities from beginning to end.

**Natura 2000** – a network of core nature conservation sites across the European Union designated under the European Union Habitats Directive and the Birds Directive.

**Nitrification** – biological oxidation of ammonia to nitrite followed by the oxidation of the nitrite to nitrate.

**Nitrification inhibitors** – synthetic or natural chemicals used to slow the process of nitrification.

**Nitrogen budget** – calculation of inputs and outputs of nitrogen across the boundaries of a system defined in time and space.

**Nitrogen cascade** – sequential transfer of N, through environmental systems. It results in multiple environmental changes as N, moves through, or is stored within, each system.

**Nitrogen-fixing crops** – crops colonized by bacteria in the root system that are able to convert N₂ into a plant-available nitrogen (for example, legumes).

**Nitrogen retention** – difference between N inputs and N outputs. The term is typically applied to freshwater catchments but can be used in other contexts.

**Nutrients** – elements present in food and feed that are indispensable for life and health.

**Paludal cultures** – crops grown in a marshy habitat, predominantly in water-logged conditions.

**Perennial crops** – crop species that live longer than two years.

**Permanent grassland** – land used for growing, continuously, forage or fodder.

**Pollution swapping** – occurs when a mitigation measure introduced to reduce levels of one pollutant results in increased levels of another pollutant.

**Ramsar sites** – wetland sites designated to be of international importance under the Convention on Wetlands of International Importance especially as Waterfowl Habitat (Ramsar Convention).

**Reactive nitrogen** – Collectively, any chemical form of nitrogen other than dinitrogen (N₂).

**Rhizobia** – soil bacteria aiding in the nitrogen fixation in leguminous plants' root nodules.

**Riparian buffer strip** – a vegetated strip of land between
agricultural land and a river or stream. It may be forested,
created with the aim of reducing the impact of the adjacent
land-use on the water quality of the stream.

**Rotational land** – agricultural practice of growing a series of different crops on the same land in successive seasons.

**Run-off** – portion of water on the soil surfaces that reaches the streams with suspended or dissolved material.

**Set-aside** – the policy of taking land out of production to reduce crop surpluses.

**Shallow injection** – the application of liquid manure by placement in shallow, vertical slots, typically about 50 mm deep, cut into the soil by a tine or disc.

**Sprinkler irrigation** – irrigation method to simulate natural rainfall.

**Struvite** – a compound consisting of magnesium ammonium phosphate. It can be precipitated from liquid slurry and wastewater, forming a solid fraction allowing the nutrients to be recovered.

**Toothed scraper** – tool with a variable number of teeth used to run over grooved floor of cattle houses, both to obtain a cleaner floor surface and to prevent slipping inside the house.

**Trailing hose** – a type of band spreader using an array of hoses to spread liquid manure close to the ground, thereby reducing ammonia emissions and odour.

**Trailing shoe** – a type of band spreader comprising an array of "shoe" units that follow the surface of the soil. The shoe-shaped units part the foliage and place liquid manure in bands on the soil surface, thereby reducing ammonia and odour emission.

**Ultrafiltration** – water-treatment process through membrane filtration.

**Urease** – enzyme that catalyses the hydrolysis of urea.

**Urease inhibitor** – compound used to slow down the hydrolysis rate of urea by reducing enzymatic activity.

**Volatilization** – transfer of a compound dissolved in water into the gaseous phase. Typically used to describe emission of ammonia into the air from substances containing ammonium.

**Welfare-economic cost-benefit analysis** – study of the impact on social welfare from the allocation of resources through a cost-benefit and social analysis.

**Woodlands** – habitat where trees are the dominant plant form.

**Yield** – amount of agricultural production harvested per unit of land area.

**Zeolite** – mineral from volcanogenic sedimentary rock having the ability for adsorption and ion exchange.
Appendix III

Workshop participants, authors and
other contributors to the process

<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>Christer Ågren</td><td>Air Pollution & Climate Secretariat (AirClim)</td><td>Sweden</td></tr><tr><td>Rauli Albert</td><td>Finnish Office of Agriculture, Forestry and Cooperatives, MTK Brussels office</td><td>Belgium</td></tr><tr><td>José Alegre Seoane</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Maria Jose Alonso</td><td>Spanish Ministry for Ecological Transition and Demographic Challenge</td><td>Spain</td></tr><tr><td>Barbara Amon</td><td>Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Germany and University of Zielona Góra, Poland</td><td>Germany</td></tr><tr><td>Rozana Anastasi</td><td>National Environmental Agency</td><td>Albania</td></tr><tr><td>Damir Bartolić</td><td>Ministry of Environment and Energy</td><td>Republic of Croatia</td></tr><tr><td>Samy Beltaief</td><td>International Fertilizer Association</td><td>France</td></tr><tr><td>Laima Berzina</td><td>Latvia University of Life Sciences and Technologies</td><td>Latvia</td></tr><tr><td>Shabtai Bittman</td><td>Agriculture and Agri-Food Canada</td><td>Canada</td></tr><tr><td>Philip Blackwell</td><td>Department of Agriculture, Food and the Marine</td><td>Ireland</td></tr><tr><td>Albert Bleeker</td><td>National Institute for Public Health and the Environment (RIVM)</td><td>The Netherlands</td></tr><tr><td>Boris Boincean</td><td>Selectia Research Institute of Field Crops</td><td>Republic of Moldova</td></tr><tr><td>Gérard Bonnis</td><td>Organisation for Economic Cooperation and Development (OECD)</td><td>France</td></tr><tr><td>Gabriele Boccasile</td><td>Regione Lombardia</td><td>Italy</td></tr><tr><td>Gabriele Borghardt</td><td>German Environment Agency</td><td>Germany</td></tr><tr><td>Cristina Branquinho</td><td>Faculty of Sciences, University of Lisbon</td><td>Portugal</td></tr><tr><td>Frank Brentrup</td><td>Yara International</td><td>Germany</td></tr><tr><td>Will J. Brownlie</td><td>UK Centre for Ecology & Hydrology and School of Geosciences, University of Edinburgh</td><td>United Kingdom</td></tr><tr><td>Michaela Budňáková</td><td>Ministry of Agriculture</td><td>Czech Republic</td></tr><tr><td>Klaus Butterbach-Bahl</td><td>Institute of Meteorology and Climate Research, Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology (KIT)</td><td>Germany</td></tr><tr><td>Gabriella Camarsa</td><td>AEIDL - the European Association for Information on Local Development</td><td>Belgium</td></tr><tr><td>Isidro Campos</td><td>European Commission, DG Agriculture and Rural Development</td><td>Belgium</td></tr><tr><td>Melissa Caruana</td><td>Environment and Resources Authority</td><td>Malta</td></tr><tr><td>Paola Cassanelli</td><td>Department for Environment, Food and Rural Affairs (Defra)</td><td>United Kingdom</td></tr></tbody></table>
# Appendix III

Workshop participants, authors and other contributors to the process

<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>John Baptist Cassar</td><td>MESDC, Rural Development Department, Agriculture Directorate</td><td>Malta</td></tr><tr><td>Marc' Andrea Cassar</td><td>Environment and Resources Authority</td><td>Malta</td></tr><tr><td>Wibke Christel</td><td>Ministry of Environment and Food of Denmark</td><td>Denmark</td></tr><tr><td>Carmen Coleto</td><td>Spanish Ministry for the Ecological Transition</td><td>Spain</td></tr><tr><td>Mihai Constantinescu</td><td>Ministry of Waters and Forests</td><td>Romania</td></tr><tr><td>Cláudia M. d. S. Cordovil</td><td>Instituto Superior de Agronomía, Universidade de Lisboa</td><td>Portugal</td></tr><tr><td>Elena Culighin</td><td>Institute of Chemistry</td><td>Republic of Moldova</td></tr><tr><td>Aisling Cunningham</td><td>Environment and Resources Authority</td><td>Malta</td></tr><tr><td>Tommy Dalgaard</td><td>Aarhus University, Department of Agroecology</td><td>Denmark</td></tr><tr><td>Miroslav Daras</td><td>Ministry of Environment of the Slovak Republic</td><td>Slovak Republic</td></tr><tr><td>Kristina Darmanin</td><td>Environment and Resources Authority</td><td>Malta</td></tr><tr><td>Alessandra De Marco</td><td>Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA)</td><td>Italy</td></tr><tr><td>Laura Lynn De Sittry</td><td>KU Leuven</td><td>Belgium</td></tr><tr><td>Wim Debeuckelaere</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Martin Dedina</td><td>Research Institute of Agricultural Engineering</td><td>Czech Republic</td></tr><tr><td>Christophe Didion</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Ika Djukic</td><td>Environment Agency Austria</td><td>Austria</td></tr><tr><td>Bettina Doeser</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Helmut Döhler</td><td>Döhler Agrar Business Consultancy</td><td>Germany</td></tr><tr><td>Jean-Louis Drouet</td><td>French National Institute for Agriculture, Food and Environment (INRAE)</td><td>France</td></tr><tr><td>Dumitru Drumea</td><td>Institute of Ecology</td><td>Republic of Moldova</td></tr><tr><td>Craig Drury</td><td>Agriculture and Agri-Food Canada (AAFC)</td><td>Canada</td></tr><tr><td>Vanminh Duong</td><td>University of Chemistry and Technology, Prague</td><td>Czech Republic</td></tr><tr><td>Anaïs Durand</td><td>Citepa</td><td>France</td></tr><tr><td>Patrick Durand</td><td>French National Institute for Agriculture, Food and Environment (INRAE)</td><td>France</td></tr><tr><td>Anna Engleryd</td><td>Swedish Environmental Protection Agency</td><td>Sweden</td></tr><tr><td>Annika Eskusson</td><td>European Commission, DG Research and Innovation</td><td>Belgium</td></tr><tr><td>Anders Feilberg</td><td>Aarhus University</td><td>Denmark</td></tr><tr><td>Carmen Fernandez Moro</td><td>Ministry of Agriculture, Fisheries and Food</td><td>Spain</td></tr><tr><td>Francisco Ferreira</td><td>New University of Lisbon</td><td>Portugal</td></tr><tr><td>Kåre Gunnar Fløystad</td><td>N2 Applied</td><td>Norway</td></tr><tr><td>Patrícia Moreira da Fonseca</td><td>Direção-Geral de Agricultura e Desenvolvimento Rural (DGADR), Direção de Serviços de Promoção da Atividade Agrícola (DSPAA)</td><td>Portugal</td></tr></tbody></table>
<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>Lise Frohn</td><td>Aarhus University, Department of Environmental Science</td><td>Denmark</td></tr><tr><td>Nana Gabriadze</td><td>National Center for Disease Control & Public Health of Georgia</td><td>Georgia</td></tr><tr><td>José Luis Gabriel</td><td>The National Institute for Agricultural and Food Research and Technology (INIA)</td><td>Spain</td></tr><tr><td>Lazizakhon Gafurova</td><td>National University of Uzbekistan</td><td>Uzbekistan</td></tr><tr><td>Sophie Génermont</td><td>French National Institute for Agriculture, Food and Environment (INRAE)</td><td>France</td></tr><tr><td>Friederike Gesing</td><td>University of Bremen, artec Sustainability Research Center</td><td>Germany</td></tr><tr><td>Markus Geupel</td><td>German Environment Agency</td><td>Germany</td></tr><tr><td>Inga Grinfelde</td><td>Latvia University of Life Sciences and Technologies</td><td>Latvia</td></tr><tr><td>Karin Groenestein</td><td>Wageningen University and Research (WUR)</td><td>The Netherlands</td></tr><tr><td>Marlies Gruber</td><td>Austrian Chamber of Agriculture</td><td>Austria</td></tr><tr><td>Yixin Guo</td><td>Princeton University</td><td>USA</td></tr><tr><td>Petra Hagström</td><td>Swedish Environmental Protection Agency</td><td>Sweden</td></tr><tr><td>Birgitte Hansen</td><td>Geological Survey of Denmark and Greenland</td><td>Denmark</td></tr><tr><td>Bernard Harris</td><td>Department of Agriculture, Food and the Marine</td><td>Ireland</td></tr><tr><td>Richard Haeuber</td><td>United States Environmental Protection Agency</td><td>USA</td></tr><tr><td>Jürg Heldstab</td><td>INFRAS</td><td>Switzerland</td></tr><tr><td>Christine Hellerström</td><td>LIFE Clean Air Farming project</td><td>Germany</td></tr><tr><td>Charles Hendrickx</td><td>Service Public de Wallonie</td><td>Belgium</td></tr><tr><td>W. Kevin Hicks</td><td>Stockholm Environment Institute (SEI), Environment and Geography Department, University of York</td><td>United Kingdom</td></tr><tr><td>Martine Hoogsteen</td><td>National Institute for Public Health and the Environment (RIVM)</td><td>The Netherlands</td></tr><tr><td>Øystein Hov</td><td>Norwegian Meteorological Institute</td><td>Norway</td></tr><tr><td>Clare M. Howard</td><td>UK Centre for Ecology and Hydrology</td><td>United Kingdom</td></tr><tr><td>Bjørn Huso</td><td>Norwegian Directorate of Agriculture</td><td>Norway</td></tr><tr><td>Nicholas Hutchings</td><td>Aarhus University</td><td>Denmark</td></tr><tr><td>Angelo Innamorati</td><td>European Commission, DG Agriculture and Rural Development</td><td>Belgium</td></tr><tr><td>Katharina Isepp</td><td>Federal Ministry for Climate Action, Environment, Energy, Mobility, Innovation and Technology (BMK)</td><td>Austria</td></tr><tr><td>Lars Stoumann Jensen</td><td>University of Copenhagen</td><td>Denmark</td></tr><tr><td>David Kanter</td><td>New York University</td><td>USA</td></tr><tr><td>Albena Karadjova</td><td>United Nations Economic Commission for Europe (UNECE)</td><td>Switzerland</td></tr><tr><td>Desislava Karaivanova</td><td>Consilium - Council of the European Union</td><td>Belgium</td></tr></tbody></table>
# Appendix III

Workshop participants, authors and other contributors to the process

<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>Theodore Karyotis</td><td>European Cooperation in Science and Technology</td><td>Greece</td></tr><tr><td>Eszter Kis-Csatári</td><td>Research Institute of Agricultural Economics</td><td>Hungary</td></tr><tr><td>Marina Kiisler</td><td>Estonian Ministry of the Environment</td><td>Estonia</td></tr><tr><td>Katja Klasinc</td><td>European Commission, DG Research and Innovation</td><td>Belgium</td></tr><tr><td>Natalia Kozlova</td><td>TFRN Expert Panel on Nitrogen in EECCA countries</td><td>EECCA</td></tr><tr><td>Sandra Krmpotic</td><td>Ministry of Environment and Energy</td><td>Republic of Croatia</td></tr><tr><td>Dominika Krol</td><td>Teagasc, Irish Food and Agriculture Development Authority</td><td>Ireland</td></tr><tr><td>Jaakko Kuisma</td><td>Ministry of the Environment</td><td>Finland</td></tr><tr><td>Indrit Kulla</td><td>Ministry of Tourism and Environment</td><td>Albania</td></tr><tr><td>Lotte Lagerwerf</td><td>National Institute for Public Health and the Environment (RIVM)</td><td>The Netherlands</td></tr><tr><td>Hayden Lalor</td><td>Department of Agriculture, Food and the Marine</td><td>Ireland</td></tr><tr><td>Gary Lanigan</td><td>Teagasc, Irish Food and Agriculture Development Authority</td><td>Ireland</td></tr><tr><td>Ketevan Lapherashvili</td><td>Ministry of Environmental Protection and Agriculture of Georgia</td><td>Georgia</td></tr><tr><td>Luis Lassaletta</td><td>CEIGRAM, Technical University of Madrid (UPM)</td><td>Spain</td></tr><tr><td>Lionel Launois</td><td>French Ministry of Agriculture</td><td>France</td></tr><tr><td>Adrian Leip</td><td>European Commission, Joint Research Centre</td><td>Italy</td></tr><tr><td>Cristina Leonardi</td><td>Ministry for the Environment</td><td>Italy</td></tr><tr><td>Charlotte Lepitre</td><td>France Nature Environnement</td><td>France</td></tr><tr><td>Susanne Lindahl</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Sergei Lukin</td><td>TFRN Expert Panel on Nitrogen in EECCA countries</td><td>EECCA</td></tr><tr><td>Rob Maas</td><td>National Institute for Public Health and the Environment (RIVM)</td><td>The Netherlands</td></tr><tr><td>Jannes Maes</td><td>European Council of Young Farmers (CEJA)</td><td>Belgium</td></tr><tr><td>Hanna Malchykhina</td><td>TFRN Expert Panel on Nitrogen in EECCA countries</td><td>EECCA</td></tr><tr><td>Silvia Maltagliati</td><td>European Commission, DG Research and Innovation</td><td>Belgium</td></tr><tr><td>Veronica Manfredi</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Filipa Marques</td><td>Portuguese Environment Agency</td><td>Portugal</td></tr><tr><td>Cristina Martinez Salas</td><td>Ministry of Agriculture, Fisheries and Food (MAPA)</td><td>Spain</td></tr><tr><td>Kate E. Mason</td><td>UK Centre for Ecology & Hydrology</td><td>United Kingdom</td></tr><tr><td>Raia Massad</td><td>French National Institute for Agriculture, Food, and Environment (INRAE)</td><td>France</td></tr><tr><td>Claire McCamphill</td><td>European Commission, DG Research and Innovation</td><td>Ireland</td></tr><tr><td>Sergiy Medinets</td><td>Odesa National I. I. Mechnikov University</td><td>Ukraine</td></tr></tbody></table>
<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>Noe Megrelishvili</td><td>Ministry of Environmental Protection and Agriculture</td><td>Georgia</td></tr><tr><td>Reto Meier</td><td>Swiss Federal Office for the Environment (FOEN)</td><td>Switzerland</td></tr><tr><td>Harald Menzi</td><td>Swiss Federal Office for the Environment (FOEN)</td><td>Switzerland</td></tr><tr><td>Naiana Milea</td><td>Ministry of Environment, Waters and Forests</td><td>Romania</td></tr><tr><td>Tom Misselbrook</td><td>Rothamsted Research, North Wyke, Okehampton, Devon</td><td>United Kingdom</td></tr><tr><td>Lidiya Moklyachuk</td><td>Institute of Soil Protection of Ukraine (ISP)</td><td>Ukraine</td></tr><tr><td>Filip Moldan</td><td>IVL Swedish Environmental Research Institute</td><td>Sweden</td></tr><tr><td>Levente Molnár</td><td>Ministry of Environment of the Slovak Republic</td><td>Slovak Republic</td></tr><tr><td>Maria Rosa Montanella</td><td>CIA-Agricoltori Italiani</td><td>Belgium</td></tr><tr><td>Elena Mosanu</td><td>Institute of Ecology and Geography</td><td>Republic of Moldova</td></tr><tr><td>John Muldowney</td><td>Department of Agriculture, Food and the Marine</td><td>Ireland</td></tr><tr><td>Donal Murphy-Bokern</td><td>Donal Murphy-Bokern</td><td>Germany</td></tr><tr><td>Liz Nichols</td><td>United States Department of State</td><td>USA</td></tr><tr><td>Nicolas Felix Nilusmas</td><td>Nouveau Point De Vue</td><td>France</td></tr><tr><td>Stephen Nottingham</td><td>AEIDL - the European Association for Information on Local Development</td><td>Belgium</td></tr><tr><td>Alina Novikova</td><td>The United Nations Economic Commission for Europe (UNECE)</td><td>Switzerland</td></tr><tr><td>Nino Obolashvili</td><td>Ministry of Environmental Protection and Agriculture</td><td>Georgia</td></tr><tr><td>Oene Oenema</td><td>Wageningen University &amp; Research</td><td>The Netherlands</td></tr><tr><td>Claudia Olazabal</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Jørgen Olesen</td><td>Aarhus University, Department of Agroecology</td><td>Denmark</td></tr><tr><td>Valentin Opfermann</td><td>European Commission, DG Agriculture and Rural Development</td><td>Belgium</td></tr><tr><td>David Pelster</td><td>Agriculture and Agri-Food Canada</td><td>Canada</td></tr><tr><td>Csaba Pesti</td><td>National Agricultural Research and Innovation Centre, Research Institute of Agricultural Economics</td><td>Hungary</td></tr><tr><td>Tiziano Pignatelli</td><td>Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA)</td><td>Italy</td></tr><tr><td>Liisa Pietola</td><td>Central Union of Agricultural Producers and Forest Owners (MTK)</td><td>Finland</td></tr><tr><td>Robert Pinder</td><td>United States Environmental Protection Agency</td><td>USA</td></tr><tr><td>Kajsa Pira</td><td>Air Pollution &amp; Climate Secretariat (AirClim)</td><td>Sweden</td></tr><tr><td>Sylvie Platel</td><td>France Nature Environnement</td><td>France</td></tr><tr><td>Merje Põlma</td><td>Ministry of Rural Affairs</td><td>Estonia</td></tr><tr><td>Mahesh Pradhan</td><td>UN Environment Programme (UNEP)</td><td>Kenya</td></tr></tbody></table>
# Appendix III

Workshop participants, authors and other contributors to the process

<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>Dominique Pritula</td><td>Environment and Climate Change Canada</td><td>Canada</td></tr><tr><td>Miguel Quemada</td><td>Technical University of Madrid (UPM)</td><td>Spain</td></tr><tr><td>Girish Rambaran</td><td>Department for Environment, Food and Rural Affairs</td><td>United Kingdom</td></tr><tr><td>Heidi Ravnborg</td><td>Ministry of Environment and Food</td><td>Denmark</td></tr><tr><td>Robert Rawlings</td><td>International Air Quality, Environmental Quality, Department for Environment, Food and Rural Affairs</td><td>United Kingdom</td></tr><tr><td>Nicole Read</td><td>UK Centre for Ecology & Hydrology</td><td>United Kingdom</td></tr><tr><td>Robert M. Rees</td><td>SRUC - Scotland's Rural College</td><td>United Kingdom</td></tr><tr><td>Katharina Rettig</td><td>Consilium - Council of the European Union</td><td>Belgium</td></tr><tr><td>Cristina Riestra</td><td>Ministry for the Ecological Transition and the Demographic Challenge</td><td>Spain</td></tr><tr><td>Leanne Roche</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Bibiana María Rodríguez Sendón</td><td>Ministry of Agriculture, Fisheries and Food (MAPA)</td><td>Spain</td></tr><tr><td>Juan José Ruiz García</td><td>Ministry of Agriculture, Fisheries and Food (MAPA)</td><td>Spain</td></tr><tr><td>Joost Salomez</td><td>Department of Environment and Spatial Development, Flemish Government</td><td>Belgium</td></tr><tr><td>Carla Santos Moore</td><td>Consilium - Council of the European Union</td><td>Belgium</td></tr><tr><td>Kimber Scavo</td><td>United States Environmental Protection Agency</td><td>USA</td></tr><tr><td>Alberto Sanz Cobena</td><td>Technical University of Madrid (UPM)</td><td>Spain</td></tr><tr><td>Bettina Schäppi</td><td>INFRAS</td><td>Switzerland</td></tr><tr><td>Martha Schlegel</td><td>UK Centre for Ecology & Hydrology</td><td>United Kingdom</td></tr><tr><td>Martin Schneekloth</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Ute M. Skiba</td><td>UK Centre for Ecology & Hydrology</td><td>United Kingdom</td></tr><tr><td>Odón Sobrino</td><td>Ministry of Agriculture, Fisheries and Food (MAPA)</td><td>Spain</td></tr><tr><td>Inna Soltys</td><td>Odesa National I. I. Mechnikov University</td><td>Ukraine</td></tr><tr><td>Till Spranger</td><td>Federal Environment Ministry</td><td>Germany</td></tr><tr><td>Janet Sprent</td><td>Royal Botanic Gardens Edinburgh</td><td>United Kingdom</td></tr><tr><td>Tiffanie Stephani</td><td>Fertilizers Europe</td><td>Belgium</td></tr><tr><td>Michael Stopford</td><td>School of Transnational Governance, European University Institute</td><td>Italy</td></tr><tr><td>Mark A. Sutton</td><td>UK Centre for Ecology & Hydrology</td><td>United Kingdom</td></tr><tr><td>Roger Sylvester-Bradley</td><td>ADAS - Agricultural Development and Advisory Service</td><td>United Kingdom</td></tr><tr><td>Teresa Tavares</td><td>The Directorate General for Agriculture and Rural Development (DGADR)</td><td>Portugal</td></tr><tr><td>Sylviane Thomas</td><td>Walloon Air & Climate Agency</td><td>Belgium</td></tr><tr><td>Margherita Tolotto</td><td>European Environmental Bureau (EEB)</td><td>Belgium</td></tr><tr><td>Aimable Uwizeye</td><td>Food and Agriculture Organization of United Nations</td><td>Italy</td></tr><tr><td>Salar Valinia</td><td>Swedish Environmental Protection Agency</td><td>Sweden</td></tr><tr><td>Antonio Vallejo</td><td>Technical University of Madrid (UPM)</td><td>Spain</td></tr></tbody></table>
<table><thead><tr><td>Name</td><td>Organisation</td><td>Country</td></tr></thead><tbody><tr><td>Laura Valli</td><td>Research Centre on Animal Production (CRPA)</td><td>Italy</td></tr><tr><td>Klaas Van der Hoek</td><td>Retired (formerly of National Institute for Public Health and the Environment (RIVM))</td><td>The Netherlands</td></tr><tr><td>Thomas Vannecke</td><td>Flemish Coordination Centre for Manure Processing (VCM vzw)</td><td>Belgium</td></tr><tr><td>Eduard Vasilev</td><td>TFRN Expert Panel on Nitrogen in EECCA countries</td><td>EECCA</td></tr><tr><td>Victoria Vertyankina</td><td>TFRN Expert Panel on Nitrogen in EECCA countries</td><td>EECCA</td></tr><tr><td>Giovanni Vialeetto</td><td>Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA)</td><td>Italy</td></tr><tr><td>Pascale Vizy</td><td>French Ministry of Ecological and Solidarity Transition</td><td>France</td></tr><tr><td>François Wakenhut</td><td>European Commission, DG Environment</td><td>Belgium</td></tr><tr><td>Madison Warwick</td><td>UK Centre for Ecology & Hydrology</td><td>United Kingdom</td></tr><tr><td>Roy Wichink Kruit</td><td>National Institute for Public Health and the Environment (RIVM)</td><td>The Netherlands</td></tr><tr><td>Wilfried Winiwarter</td><td>International Institute for Applied Systems Analysis (IIASA)</td><td>Austria</td></tr><tr><td>Stefanie Wolter</td><td>German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety</td><td>Germany</td></tr><tr><td>Roald Wolters</td><td>Ministry of Infrastructure and Water Management</td><td>The Netherlands</td></tr><tr><td>Sebastian Wulf</td><td>Kuratorium für Technik und Bauwesen in der Landwirtschaft (KTBL)</td><td>Germany</td></tr></tbody></table>

Abbreviations: EECCA, Eastern Europe, Caucasus and Central Asia.
**'Nitrogen Opportunities for Agriculture, Food & Environment'** is the first ever United Nations Guidance Document on Integrated Sustainable Nitrogen Management. It brings all major forms and impacts of nitrogen together for multiple environmental and economic benefits.

The Nitrogen Guidance Document focuses on agriculture in the context of the food system and environment. It identifies the principles of integrated sustainable nitrogen management, followed by measures to reduce nitrogen losses from livestock housing and manure storage, including measures to promote nutrient recovery. It then identifies measures to reduce nitrogen losses from organic and inorganic fertilizers, and measures that focus on landscape and land-use management, finishing by considering coherent 'measures packages'.

While this guidance document has been formally adopted by the UNECE Convention on Long-range Transboundary Air Pollution (ECE/EB.AIR/149), it is equally relevant to support national and international policies on water, climate, biodiversity, soils and stratospheric ozone depletion. The document contributes to implementing UNEA Resolutions 4/14 and 5/2, and the Colombo Declaration ambition to halve nitrogen waste from all sources.

The document has been prepared under the lead of the Task Force on Reactive Nitrogen of the UNECE Convention, with the support of the GEF/UNEP International Nitrogen Management System.

<figure><img src="image_179.png" /></figure>

UNECE

<figure><img src="image_180.png" /></figure>

Task
Force on
Reactive
Nitrogen

<figure><img src="image_181.png" /></figure>

<figure><img src="image_182.png" /></figure>

INMS

<figure><img src="image_183.png" /></figure>

UK Centre for
Ecology & Hydrology