Steffanie Schirren
Institute of Climate-Smart Agriculture

Bundesallee 65
38116 Braunschweig
Phone: +49 531 596 2602
Fax: +49 531 596 2699

GülleBest - Innovative slurry and digestate application techniques


Slurry application (c) TI-AK/Caroline Buchen
Slurry application (© TI-AK/Caroline Buchen)

Mitigation of ammonia and greenhouse gas emission and  improving nitrogen use efficiency by innovative
slurry and digestate application techniques for growing crops

How can slurry and digestate be used in such a way that greenhouse gas and ammonia emissions are kept to a minimum? The researchers in the "GülleBest" joint project are investigating this question.

Background and Objective

One of the most important measures to reduce ammonia and greenhouse gas emission from crop production is the adoption of new low-emission application techniques for slurry and digestate. With the amendment of the new fertilization ordinance in Germany, slurry and digestaste may only be applied to arable land to a limited extent in autumn. Thus nitrogen surpluses after harvesting the main crop and their negative consequences for groundwater and climate can be avoided. Therefore, slurry and digestate application will increasingly take place in growing field crops by means of band-shaped application to the soil surface, in line with the nitrogen requirements of the crops. This shift might induce increasing emissions in particular of ammonia because ammonia emissions are considerable higher for band application than immediate incorporation which is an easy option to reduce emissions from slurry applied before sowing of the next crop. Thus, low-emission application techniques with high nutrient use efficiency have to be developed and adopted for growing crops.


Within the joint project „GülleBest“ emission reduction, fertiliser efficiency and practical suitability of the following application techniques for slurry and digestates in growing winter wheat and grassland stands will be evaluated:

  • Application by trailing hose and slot technique,
  • Combination of slot technique with application of nitrification inhibitors,
  • Slurry acidification and application with trailing hose.

The experiments will be conducted on different soil sites in Germany in comparison to the future prescribed band-shaped application to the soil surface.

The project includes the following working packages:

WP1) A framework of four field experiments on different soil types in Germany,

WP2) The evaluation of the full life-cycle emissions on basis of a live-cycle-analysis,

WP3) An economic evaluation on field and farm scale of different techniques used,

WP4) Up-scaling of findings to national inventories,

WP5) The integrative assessment and knowledge transfer to agricultural practice.

Links and Downloads


Involved Thünen-Partners

Involved external Thünen-Partners

Funding Body

  • Federal Ministry of Food und Agriculture (BMEL)
    (national, öffentlich)
  • Federal Office for Agriculture and Food (BLE)
    (national, öffentlich)


8.2018 - 10.2021

More Information

Projekt type:
Funding program: Innovationsförderung
Project status: ongoing