2021-03 - 2024-02 | Agency for Renewable Resources (FNR, Gülzow, Germany)

In this project, the effect of urease- and nitrification-inhibited ammonium sulfate urea compared to non-inhibited ammonium sulfate urea (AS-HS) on N use efficiency in commodity crop production will be investigated at selected sites. Simultaneously, the aim is to detect a possible interaction of the inhibitors when double-inhibited AS-HS is used. The combined N stabilization with urease and nitrification inhibitors suggests a significant mitigation of ammonia, nitrous oxide and nitrate losses. The mentioned effects and the influence on yield will be tested in crop rotation trials with silage maize and integrated gas measurements (NH3 and N2O) under practical conditions. In order to obtain reliable statements on the total extent of gaseous N losses, the leachate quantity and the nitrate leaching risk will additionally be determined by means of lysimeter experiments, and the actual N2 emission will be determined with the aid of laboratory incubation experiments. This is of central importance for the determination of realistic fertilizer N-balances, as gaseous N2 losses due to denitrification represent an important, but most difficult to detect N-loss pathway. In addition to the already existing ecotoxicological studies and long-term tests on environmental behavior, the ecotoxicological effect or the fate of the inhibitors and, as far as possible, their degradation products in the environment are to be modeled in order to investigate possible problem shifts, in particular water pollution, at an early stage. The measure will be evaluated by calculating area-related N-loss rates and three-year N-balances as well as by means of eco-efficiency analyses. Thus, the measure will be evaluated with regard to N-losses as well as with regard to operational advantages and disadvantages. Environmentally and resource-optimized mineral N fertilization systems will be derived from the results.

2020 - 2023-11 | Landwirtschaftliche Rentenbank (Frankfurt, Germany)

The research network analyzes and evaluates measures to reduce NH3 emissions from the application of synthetic nitrogen fertilizers and to increase the efficiency of their application. The investigations focus on the nitrogen fertilizers urea, calcium ammonium nitrate, ammonium nitrate-urea solution and ammonium sulfate-urea, which together are responsible for more than 85% of the NH3 emission from synthetic nitrogen fertilizers used in Germany and which represent about 70% of the nitrogen applied with synthetic fertilizers. The assessment is based on different NH3 measurement systems, the quantitative accuracy of which is tested and ensured by the network. Recommendations will be developed on how agriculture can optimize the application of synthetic nitrogen fertilizers in the context of increasing nitrogen efficiency and securing yields while reducing emissions that are harmful to the environment, climate and health. The collaborative project comprises both a Germany-wide network of coordinated field experiments to evaluate fertilizer strategies in the context of ammonia emission reduction, nitrogen efficiency and yield security, and the transfer of knowledge into practice.

Project homepage

2018-11 to 2022-03 | Federal Ministry of Food and Agriculture (BMEL, Bonn, Germany)

Nutrient-efficient, environmentally friendly and climate-friendly fertilization with liquid manure and fermentation residues is one of the most important starting points for reducing emissions in crop cultivation that are harmful to the climate and the environment. The amendment to the Fertilizer Ordinance restricts the spreading of liquid manure and digestate on arable land in the fall. This helps to avoid nitrogen surpluses after the main crop has been harvested and their negative consequences for groundwater and the climate. The application of slurry and digestate will therefore increasingly be carried out in growing stands by means of banded application to the soil surface, in line with the nitrogen requirements of the crops.This new regulation may even lead to an increase in ammonia emissions from organically fertilized arable land and grassland, which are harmful to the climate and the environment, as strip application to the stands causes higher emissions than immediate incorporation on uncultivated land. Innovative, low-emission techniques that both optimally serve the nutrient requirements of the crop and minimize emissions that are harmful to the environment and the climate are therefore required, especially for growing stands.

Press release Uni-Hohenheim (in German) Project homepage

Publications

Nyameasem, J. K., Zutz, M., Kluß, C., Huf, M. ten, Essich, C., Buchen-Tschiskale, C., Ruser, R., Flessa, H., Olfs, H.-W., Taube, F., & Reinsch, T. (2022). Impact of cattle slurry application methods on ammonia losses and grassland nitrogen use efficiency. Environmental Pollution, 315, 120302. DOI:10.1016/j.envpol.2022.120302

2018-11 - 2022-03 | Federal Ministry of Food and Agriculture (BMEL, Bonn, Germany)

The aim of the GHG-ZWIFRU project is to reduce greenhouse gas emissions from agriculture by quantifying and optimizing the positive effects of intercropping. The project focuses on three impact pathways along which site-adapted intercropping systems can contribute to climate protection:

1. The reduction of direct N2O emissions after harvest of the main crop,
2. the reduction of nitrate leaching over winter and the associated avoidance of indirect N2O emissions, and
3. a reduced N fertilizer requirement in subsequent crops, which also leads to reduced GHG emissions.

Within the framework of the joint project GHG-ZWIFRU, the climate protection effects and the yield effectiveness of different intercropping systems upstream of maize and sugar beet will be analyzed and evaluated on a site-specific basis. A practical method for the estimation of the N-quantities bound in the intercrop biomass as well as the N-release to be expected in the following crops for different intercrop types and stands will be developed.

Publications

Essich, L., Nkebiwe, P.M., Schneider, M., Ruser, R. (2020) Is crop residue removal to reduce N2O emissions driven by quality or quantity? A field study and meta-analysis. Agriculture, 10, 546. DOI:10.3390/agriculture10110546

2015-03 - 2018-02 | EuroChem Agro (Mannheim, Germany)

The interaction of high mineral N availability and a simultaneously high C turnover is likely the reason why, compared to a surface application, extremely high N2O emissions occur with slurry injection. Although this effect has been frequently demonstrated, no strategies to mitigate these injection-induced N2O emissions have been tested to date. The addition of nitrification inhibitors could offer an interesting solution here, because nitrate formation from manure-borne ammonium occurs with a time delay, and thus a desynchronization of nitrate availability with C supply (from manure) could be achieved for the predominant C-heterotrophic, denitrifying biomass.

Detailed project description (in German)

Publications

Herr, C., Mannheim, T., Müller, T., Ruser, R. (2019) Effect of cattle slurry application techniques on N2O and NH3 emissions from a loamy soil. J. Plant Nutr. Soil Sci. 182, 964-979. DOI: 10.1002/jpln.201800376

Herr, C., Mannheim, T., Müller, T., Ruser, R. (2020) Effect of nitrification inhibitors on N2O emissions after cattle slurry application. Agronomy 10, 1174: DOI:10.3390/agronomy10081174

2015-01 - 2018-12 | EuroChem Agro (Mannheim, Germany)

Publications

See chapters 9 and 10 in Ivan Guzman-Bustamante's disseration:

• Effects of urea fertilization and urease and nitrification inhibitor on gaseous nitrogen fluxes from a loamy soil
• Combined application of urease inhibitor NBPT and nitrification inhibitor DMPSA to urea: an incubation experiment

2013-01 - 2015-12 | Agency for Renewable Resources  (FNR, Gülzow, Germany)

The aim of this sub-project is to record the N2O emissions from rapeseed areas throughout the year on a frost-intensive site and to derive cultivation variants that ensure a significant reduction in greenhouse gas pollution in rapeseed cultivation. In order to take into account the known high inter-annual variability of trace gas fluxes, three-year measurements are planned. The work in Hohenheim comprises the following four focal points:

1. Establishment and supervision of a plot trial at the Hohenheim site (Ihinger Hof). The selection of the trial variants was made in coordination with the other subapplicants. In addition to the variants investigated in the intensive measurement program, the reduction potential of a nitrification inhibitor with mineral N fertilization is also quantified.
2. Determination of trace gas fluxes over three experimental years. Annual emissions are calculated from this and site-specific emission factors for rapeseed are derived.
3. Calculation of the emission reduction potential of individual measures in comparison to standard practice management in rapeseed cultivation.
4. Determination of the turnover of crop residues using 15N techniques. These investigations are carried out both in laboratory approaches and in the field.

Press release Uni-Hohenheim (in German) Final report (in German)

Publications

Ruser, R., Fuß, R., Andres, M., Hegewald, H., Kesenheimer, K., Köbke, S., Räbiger, T., Quinones, T.S., Augustin, J., Christen, O., Dittert, K., Kage, H., Lewandowski, I., Prochnow, A., Stichnothe, H., Flessa, H. (2017) Nitrous oxide from winter oilseed rape cultivation. Agric. Ecosys. & Environ. 249, 57-69. DOI: 10.1016/j.agee.2017.07.039

Kesenheimer, K., Pandeya, H. R., Müller, T., Buegger, F., Ruser, R. (2018) Nitrous oxide emissions after incorporation of winter oilseed rape (Brassica napus L.) residues under two different tillage treatments. J. Plant Nutr. Soil Sci. 182, 48-59. DOI: 10.1002/jpln.201700507

Räbiger, T., Andres, M., Hegewald, H., Kesenheimer, K., Köbke, S., Suarez-Quinones, T., Böttcher, U., Kage, H. (2020) Indirect nitrous oxide emissions from oilseed rape cropping systems by NH3 volatilization and nitrate leaching as affected by nitrogen source, N rate and site conditions. Europ. J. Agronomy 116, 126039. DOI: 10.1016/j.eja.2020.126039

Kesenheimer, K., Flessa, H., Augustin, J., Hegewald, H., Köbke, S., Dittert, K., Räbiger, T., Suarez Quinones, T., Prochnow, A., Hartung, J., Fuß, R., Stichnothe, H., Ruser, R. (2021) Nitrification inhibitors reduce N2O emissions induced by application of biogas digestate to oilseed rape. Nutr. Cycl. Agroecosyst, DOI: 10.1007/s10705-021-10127-8

Mallast, J., Stichnothe, H., Flessa, H., Fuß, R., Lucas-Moffat, A. M., Petersen-Schlapkohl, U., Augustin, J., Hagemann, U., Kesenheimer, K., Ruser, R., Suárez Quiñones, T., Prochnow, A., Dittert, K., Huth, V., Glatzel, S. (2021): Multi-variable experimental data set of agronomic data and gaseous soil emissions from maize, oilseed rape and other energy crops at eight sites in Germany. Open Data Journal for Agricultural Research 7. DOI: 10.18174/odjar.v7i0.16124

2011-03 - 2014-02 | Federal Agency for Agriculture and Food  (BLE, Bonn, Germany)

In the project, measures to avoid nitrogen surpluses are to be investigated with regard to their climate and environmental impact. The measures are analogous to those defined in the consortium application (grant number 09HS16). The inclusion of a site with silt-rich texture represents an optimal extension to the consortium application. In the project, gaseous losses (N2O, N2) as well as losses of excess N via nitrate leaching in outdoor vegetable production are to be made transparent and balance gaps are to be closed. The environmental model 'Expert-N' will be used to test suitable measures for environmental relief by means of simulations.

Work packages:AP1: Year-round recording of N2O release in Hohenheim and at Rinkenbergerhof to compare the trace gas release of two sites with very different soil textures.AP2: Evaluation of measures to avoid N-surpluses with regard to atmospheric and groundwater pollution and derivation of recommendations for action.AP3: Establishment of acetylene inhibition and estimation of N2 losses from denitrification and collection of annual data sets on the sandy experimental plots.AP4: Calibration and validation of the environmental model 'Expert-N' for the Hohenheim site. Derivation of measures for N2O mitigation by means of simulation and testing of the variants with the greatest mitigation potential in the field.

Final Report (in German)

Publications

Seiz, P., Guzman-Bustamante, I., Schulz, R., Muller, T., Ruser, R. (2019) Effect of crop residue removal and straw addition on nitrous oxide emissions from a horticulturally used soil in south Germany. Soil Sci. Soc. Am. J. 83, 1399-1409, DOI: 10.2136/sssaj2018.11.0448

Budhathoki, R., Panday, D., Seiz, P., Ruser, R., Müller, T. (2021): Effect of broccoli residue and wheat straw addition on nitrous oxide emissions in silt loam soil. Nitrogen 2, 99-109. DOI:10.3390/nitrogen2010007

2011-02 - 2013-01 | K&S Nitrogen (Mannheim, Germany)

Publications

Guzman-Bustamante, I., Schulz, R., Müller, T., Ruser, R. (2022): Split N application and DMP based nitrification inhibitors mitigate N2O losses in a soil cropped with winter wheat. Nutrient Cycling in Agroecosystems. DOI: 10.1007/s10705-022-10211-7

Guzman-Bustamante, I., Winkler, T., Schulz, R., Müller, T., Mannheim, T., Laso Bayas, J.C., Ruser, R. (2019) N2O emissions from a loamy soil cropped with winter wheat as affected by N-fertilizer amount and nitrification inhibitor. Nutr. Cycl. Agroecosyst. 114, 173-191. DOI: 10.1007/s10705-019-10000-9

2008-02 - 2011-01 | German Federal Foundation for the Environment (DBU, Osnabrück, Germany)

A high N-efficiency of crop production in agro-ecosystems combined with low N-losses is the mandatory prerequisite for environmentally sound land management, which is a particular challenge for field vegetable production. Compared to cereals, some vegetable crops (category III and partly category II, Annex Amendment to the Fertiliser Ordinance) are associated with sometimes very high N losses, as they are harvested in a phase of strong vegetative growth. This can cause a large N loss potential through transport into neighbouring compartments such as groundwater (nitrate displacement and dissolved N2O - indirect emission) and/or the atmosphere (such as the climate-relevant trace gas N2O - direct emission), which is an environmentally relevant problem.
Given the high mineral N content of soils used for vegetable production, it could be assumed that the annual N2O emission is significantly higher than in cereals or maize due to the higher N input and the less favourable synchronisation of supply and demand. Although the N2O emission, which can only be reliably mapped with the help of annular data sets, is an important component of the N balances, it has so far only been estimated in vegetable production. Up to the start of the project, there were no annular data on N2O release from vegetable-growing areas available for our latitudes. Further N surpluses can also lead to nitrate contamination of groundwater, especially in autumn.
The objectives of the project were to record direct and indirect (dissolved) N2O emissions throughout the year and to develop suitable strategies that can be easily implemented in practice to reduce N2O emissions and to mitigate nitrate shifting in soils used intensively for vegetable production. The focus was to be on practice-oriented strategies such as different fertilisation measures and optimised management of intercropping, with yield stability and safeguarding as the criteria for success.

Detailed project description and results (in German)

Publications

Pfab, H., Palmer, I., Buegger, F., Fiedler, S., Müller, T., Ruser, R. (2011) N2O fluxes from a Haplic Luvisol under intensive production of lettuce and cauliflower as affected by different N fertilization strategies. J. Plant Nutr. Soil Sci. 174, 545-553. DOI: 10.1002/jpln.201000123

Kleineidam, K., Košmrlj, K., Kublik, S., Palmer, I., Pfab, H., Ruser, R., Fiedler, S., Schloter, M. (2011) Influence of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on ammonia-oxidizing bacteria and archaea in rhizosphere and bulk soil. Chemosphere 84, 182-186. DOI: 10.1016/j.chemosphere.2011.02.086

Pfab, H., Palmer, I., Buegger, F., Fiedler, S., Müller, T., Ruser, R. (2012) Influence of a nitrification inhibitor and of placed N-fertilization on N2O fluxes from a vegetable cropped loamy soil. Agric. Ecosys. & Environ. 150, 91-101. DOI: 10.1016/j.agee.2012.01.001