Data extracted in October 2020
Fiche created in December 2023

Note to the reader: This general fiche summarises all the environmental and climate impacts of LOW AMMONIA EMISSION TECHNIQUES FOR MINERAL FERTILISATION found in a review of 5 synthesis papers[1]. These papers were selected from an initial number of 62 obtained through a systematic literature search strategy, according to the inclusion criteria reported in section 4. The impacts reported here are those for which there is scientific evidence available in published synthesis papers, what does not preclude the farming practice to have other impacts on the environment and climate still not covered by primary studies or by synthesis papers.

The synthesis papers review a number of primary studies ranging from 39 to 376. Therefore, the assessment of impacts relies on a large number of results from the primary studies, obtained mainly in field conditions, or sometimes in lab experiments or from model simulations.

1.     DESCRIPTION OF THE FARMING PRACTICE

• Description:
  • Low-ammonia-emission techniques for mineral fertilisation are fertilisation techniques used to reduce agricultural emissions of ammonia from mineral fertilisers.
• Key descriptors:
  • Low-ammonia-emission techniques for mineral fertilisation include improved fertilisation techniques based on: 1) use of non-urea based fertilisers; 2) change in fertiliser placement: deep placement; 3) fertiliser time distribution: split application; 4) use of irrigation after fertilisation; 5) use of amendment with sorbents; 6) crop residue left on soil.
  • Low-ammonia-emission techniques for mineral fertilisation exclude strategies aimed at reducing ammonia emissions from organic fertilisers, livestock and manure management.
    

2.    EFFECTS OF THE FARMING PRACTICE ON CLIMATE AND ENVIRONMENTAL IMPACTS

We reviewed the impacts of mineral fertilisation when using low-ammonia-emission techniques, as compared to conventional fertilisation techniques (Table 1).

The table below shows the number of synthesis papers with statistical tests reporting i) a significant difference between the Intervention and the Comparator, that is to say, a significant statistical effect, which can be positive or negative; or ii) a non-statistically significant difference between the Intervention and the Comparator. In addition, we include, if any, the number of synthesis papers reporting relevant results but without statistical test of the effects. Details on the quality assessment of the synthesis papers can be found in the methodology section of this WIKI.

Out of the 5 selected synthesis papers, 3 included studies conducted in Europe, and 5 have a quality score higher than 50%.

Table 1: Summary of effects. Number of synthesis papers reporting positive, negative or non-statistically significant effects on environmental and climate impacts. The number of synthesis papers reporting relevant results but without statistical test of the effects are also provided. When not all the synthesis papers reporting an effect are of high quality, the number of synthesis papers with a quality score of at least 50% is indicated in parentheses. Some synthesis papers may report effects for more than one impact, or more than one effect for the same impact.

3.     FACTORS INFLUENCING THE EFFECTS ON CLIMATE AND ENVIRONMENTAL IMPACTS

The factors significantly influencing the size and/or direction of the effects on the impacts, according to the synthesis papers included in this review, are reported below. Details about the factors can be found in the summaries of the meta-analyses available in this WIKI.

Table 2: List of factors reported to significantly affect the size and/or direction of the effects on environmental and climate impacts, according to the synthesis papers reviewed. The reference number of the synthesis papers where those factors are explored is given in parentheses.

4.    SYSTEMATIC REVIEW SEARCH STRATEGY

Table 3: Systematic review search strategy - methodology and search parameters.

5.     SYNTHESIS PAPERS INCLUDED IN THE REVIEW

Table 4: List of synthesis papers included in this review. More details can be found in the summaries of the meta-analyses.

Disclaimer: These fiches present a large amount of scientific knowledge synthesised to assess farming practices impacts on the environment, climate and productivity. The European Commission maintains this WIKI to enhance public access to information about its initiatives. Our goal is to keep this information timely and accurate. If errors are brought to our attention, we will try to correct them. However, the Commission accepts no responsibility or liability whatsoever with regard to the information on these fiches and WIKI.

[1] Synthesis research papers include either meta-analysis or systematic reviews with quantitative results. Details can be found in the methodology section of the WIKI.