/
Blog Posts
Data extracted in September 2021
Fiche created in December 2023
Note to the reader: This general fiche summarises all the environmental and climate impacts of GRASSLAND MANAGEMENT found in a review of 33 synthesis papers[1]. These papers were selected from an initial number of 1022 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 12 to 141. 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:
- Grasslands are areas of land predominantly covered by communities of grass-like plants and forbs and may include sparsely occurring trees and shrubs. In the Eurostat classification, percentages of area covered by such canopies are limited to less than 10 % in the case of trees and to less than 20 % in the case of shrubs (i.e., low woody plants capable of reaching heights of up to 5 metres)[2] or shrubs and trees together.[3] However, in the scientific literature reviewed here, grasslands are usually more broadly defined and might not fully meet such canopy limits.
- This review includes a wide variety of grassland types: savannah, grassy deserts, seasonally flooded grasslands, prairies, meadows, pastures, rangelands, salt-marshes, bioenergy perennial grasslands, calcareous grasslands and wooded grasslands. Grasslands differ in terms of: management intensity (natural, semi-natural, improved and intensively managed); management history: permanent and temporary; successional stage (old successional and secondary grasslands); biomes and climates (semi-arid, temperate, tropical, Mediterranean, tundra, alpine, subalpine, artic and subartic).
- Fodder crops are not included as grasslands.
- This review includes several interventions on grasslands:
- Soil organic amendments are materials of plant or animal origin that can be added to soil, such as manures, biosolids, green wastes, and composts, to improve the soil quality in terms of its structure and biochemical function.[4] This includes also biochar, which is charcoal produced by pyrolysis of biomass in the absence of oxygen.
- Enhanced-efficiency fertilisers (EEF) are different types of fertilisers or products associated to fertilisers, which have been developed to better synchronize fertiliser nitrogen (N) release with crop uptake, offering the potential for enhanced N-use efficiency (NUE) in crops and reduce losses[5]. This review includes the use of different types of EEF, namely nitrification inhibitors, urease inhibitors and polymer-coated fertilisers.
- Fertilisers are natural or synthetic substances containing chemical elements such as nitrogen, phosphorus (P) and potassium (K) that are applied to soils to improve growth and productiveness of plants.[6] This review includes the use of both mineral and organic conventional fertilisers.
- Mowing is a harvesting practice consisting on cutting the grass.
- Grazing is a method of animal husbandry in which livestock are allowed to feed outdoors consuming wild vegetation. Please, note that in this set of fiches grazing is only explored when compared to mowing. Grazing and different grazing intensity are explored in a separate set of fiches.
- Increasing grass/forb species richness is a practice normally used to improve the agronomical performance of some grasslands. It consists on reseedings, generally with pluriannual grasses and legumes.[7]
- Key descriptors:
- This review does not include other practices conducted in grasslands such as grazing nor the conversion of other agricultural land uses to grasslands, which are assessed in separate sets of fiches.
- The management practices reviewed here are only conducted in grasslands. However, the use in croplands (i.e., with no distinction between arable lands and grasslands) of nitrification inhibitors and other enhance-efficiency fertilisers, biochar and other soil organic amendments and fertilisers, are assessed in other sets of fiches.
- For greenhouse gas (GHG) emissions, the use of fertilisers is explored separately for N and P fertilisers as effects slightly differ.
- This review does not include grazing or other management practices (i.e, soil amendment and fertilisation, mowing, increasing grass species richness) conducted in grasslands, which are assessed in separate sets of fiches.
2. EFFECTS OF THE FARMING PRACTICE ON CLIMATE AND ENVIRONMENTAL IMPACTS
We reviewed the impacts in grasslands of different soil management practices (namely, the use of enhanced-efficiency fertilisers, soil organic amendments and conventional fertilisers) compared to grasslands without such management. We also reviewed the impacts in grasslands of grazing, mowing more or less than once a year compared to grasslands mowed once a year. Finally, we reviewed the impacts in grasslands of practices pursuing to increase grass/forb species richness compared to grasslands with lower or only one species.
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.
All selected synthesis papers included studies conducted in Europe , and 32 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.
|
|
|
| Statistically tested | Non-statistically tested | ||
Impact | Metric | Intervention | Comparator | Significantly positive | Significantly negative | Non-significant | |
Decrease Air pollutants emissions | Ammonia emissions | Enhance-efficiency fertilisers | No enhance-efficiency fertilisers | 0 | 0 | 0 | 1 (0) |
Increase Biodiversity | Biodiversity | Delayed first mowing date | Early first mowing date | 1 | 0 | 1 | 0 |
Fertilisation | No fertilisation | 1 | 4 | 1 | 0 | ||
Grazing | Mowing once per year | 0 | 0 | 1 | 0 | ||
Mowing less than once a year | Mowing once per year | 0 | 1 | 0 | 0 | ||
Mowing more than once a year | Mowing once per year | 1 | 0 | 0 | 0 | ||
Soil organic amendment | No amendment | 0 | 0 | 2 | 0 | ||
Increase Carbon sequestration | Soil organic carbon | Increased grass species richness | Mono- and low grass species richness | 1 | 0 | 2 | 0 |
Soil organic amendment | No amendment | 1 | 0 | 0 | 0 | ||
Decrease GHG emissions | GHG emissions | Enhance-efficiency fertilisers | No enhance-efficiency fertilisers | 3 | 0 | 2 | 0 |
N fertilisation | No fertilisation | 0 | 3 | 0 | 0 | ||
NP fertilisation | No fertilisation | 0 | 1 | 0 | 0 | ||
P fertilisation | No fertilisation | 0 | 0 | 1 | 0 | ||
Soil organic amendment | No biochar | 0 | 0 | 1 | 0 | ||
Increase Grassland production | Crop yield | Enhance-efficiency fertilisers | No enhance-efficiency fertilisers | 1 | 0 | 0 | 0 |
Fertilisation | No fertilisation | 7 | 0 | 4 | 0 | ||
Increased grass species richness | Mono- and low grass species richness | 3 | 0 | 0 | 0 | ||
Soil organic amendment | No amendment | 2 | 0 | 0 | 0 | ||
Soil organic amendment | No biochar | 0 | 1 | 0 | 0 | ||
Decrease Heavy metals pollution | Heavy metals | Soil organic amendment | No amendment | 0 | 1 | 0 | 0 |
Decrease Nutrient leaching and run-off | NO3 leaching | Enhance-efficiency fertilisers | No enhance-efficiency fertilisers | 1 | 0 | 0 | 0 |
Decrease Nutrient leaching and run-off | Nutrient loss | Soil organic amendment | No amendment | 0 | 1 | 0 | 0 |
Increase Pests and diseases | Pests | Soil organic amendment | No amendment | 0 | 0 | 1 | 0 |
Increase Plant nutrient uptake | Nutrient use efficiency | N fertilisation | No fertilisation | 1 | 0 | 0 | 0 |
Increase Soil biological quality | Soil microorganisms | Increased grass species richness | Mono- and low grass species richness | 4 | 0 | 3 | 0 |
N fertilisation | No fertilisation | 2 | 2 | 4 | 0 | ||
Decrease Soil erosion | Soil erosion | Soil organic amendment | No amendment | 1 | 0 | 0 | 0 |
Increase Soil nutrients | Soil nutrients | Fertilisation | No fertilisation | 2 | 1 | 1 | 0 |
Increased grass species richness | Mono- and low grass species richness | 1 | 0 | 1 | 0 | ||
Increase Soil water retention | Soil water retention | N fertilisation | No fertilisation | 0 | 0 | 1 | 0 |
Soil organic amendment | No amendment | 1 | 0 | 0 | 0 | ||
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.
Impact | Factors |
Biodiversity | Climate (Ref25), Date of the early cut (Ref30), Disturbance prior to restoration (Ref3), Duration of treatment (Ref25), Fertiliser type (Ref25), Geographical area (Ref27), Grassland type (Ref27), Historical management (Ref27), Interaction between time since treatment and seeding prior to restoration (Ref3), Mowing date (Ref27), N application rate (Ref32), N content in amendment (Ref13), N fertiliser application rate (Ref25), Organism (Ref27) and Recent management (Ref27) |
Carbon sequestration | Amendment rate (Ref13), Duration of treatment (Ref9, Ref10), Grass plant species richness (Ref9, Ref10), Interaction between grass plant species richness and experimental duration (Ref9), N content in amendment (Ref13) and Time between treatment and measurement (Ref13) |
GHG emissions | Deposition season (Ref19), Excreta type (Ref19) and N fertiliser application rate (Ref18) |
Grassland production | Amendment rate (Ref13), Aridity index (Ref10), Burned before treatment (Ref3), Climate (Ref8, Ref21), Crop type (Ref8), Duration of treatment (Ref9, Ref10), Grass plant species richness (Ref9, Ref10), Interaction between grass plant species richness and experimental duration (Ref9), Mean annual temperature (Ref3), N application rate (Ref21), P fertiliser application rate (Ref8), Plot area (Ref10), Seeding prior to restoration (Ref3), Soil Olsen P levels (Ref8), Study duration (Ref19), Study type (Ref19), Time between treatment and measurement (Ref13), Time since treatment (Ref3) and Timing of application (Ref19) |
Heavy metals pollution | N content in amendment (Ref13) |
Nutrient leaching and run-off | Application rate (Ref19), Deposition season (Ref19), N content in amendment (Ref13) and Timing of application (Ref19) |
Plant nutrient uptake | N fertiliser application rate (Ref28) |
Soil biological quality | Duration of treatment (Ref23 and Ref29) |
Soil erosion | Amendment rate (Ref13) and N content in amendment (Ref13) |
Soil nutrients | Climate (Ref21) and N application rate (Ref21) |
Soil water retention | Duration of treatment (Ref21) |
4. SYSTEMATIC REVIEW SEARCH STRATEGY
Table 3: Systematic review search strategy - methodology and search parameters.
Parameter | Details |
Keywords | WOS: (TS=("grazing*" OR "grassland*" OR "pasture*" OR "rangeland")) AND TS=(("meta-analy*" OR "systematic* review*" OR "evidence map" OR "global synthesis" OR "evidence synthesis" OR "research synthesis")) |
Time reference | No time restriction. |
Databases | Web of Science and Scopus: run on 21 September 2021 |
Exclusion criteria | The main criteria that led to the exclusion of a synthesis paper are: |
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.
Ref Num | Author(s) | Year | Title | Journal | DOI |
Ref1 | Chen, J; Feng, M; Cui, Y; Liu, G | 2021 | The impacts of nitrogen addition on upland soil methane uptake: A global meta-analysis | SCIENCE OF THE TOTAL ENVIRONMENT, 795, 148863. | 10.1016/j.scitotenv.2021.148863 |
Ref2 | Chen, XL; Chen, HYH; Searle, EB; Chen, C; Reich, PB | 2021 | Negative to positive shifts in diversity effects on soil nitrogen over time | NATURE SUSTAINABILITY, 4, 225–232. | 10.1038/s41893-020-00641-y |
Ref3 | Ploughe, LW; Akin-Fajiye, M; Gagnon, A; Gardner, WC; Fraser, LH | 2021 | Revegetation of degraded ecosystems into grasslands using biosolids as an organic amendment: A meta-analysis | APPLIED VEGETATION SCIENCE, 24(1), e12558. | 10.1111/avsc.12558 |
Ref4 | Barry, KE; van Ruijven, J; Mommer, L; Bai, YF; Beierkuhnlein, C; Buchmann, N; de Kroon, H; Ebeling, A; Eisenhauer, N; Guimaraes-Steinicke, C; Hildebrandt, A; Isbell, F; Milcu, A; Nesshover, C; Reich, PB; Roscher, C; Sauheitl, L; Scherer-Lorenzen, M; Schmid, B; Tilman, D; von Felten, S; Weigelt, A | 2020 | Limited evidence for spatial resource partitioning across temperate grassland biodiversity experiments | ECOLOGY, 101(1), e02905. | 10.1002/ecy.2905 |
Ref5 | Chen, XL; Chen, HYH; Chen, C; Ma, ZL; Searle, EB; Yu, ZP; Huang, ZQ | 2020 | Effects of plant diversity on soil carbon in diverse ecosystems: A global meta-analysis | BIOLOGICAL REVIEWS, 95(1), 167-183. | 10.1111/brv.12554 |
Ref6 | Jia, XY; Zhong, YQW; Liu, J; Zhu, GY; Shangguan, ZP; Yan, WM | 2020 | Effects of nitrogen enrichment on soil microbial characteristics: From biomass to enzyme activities | GEODERMA, 366, 114256. | 10.1016/j.geoderma.2020.114256 |
Ref7 | Prather, RM; Castillioni, K; Kaspari, M; Souza, L; Prather, CM; Reihart, RW; Welti, EAR | 2020 | Micronutrients enhance macronutrient effects in a meta-analysis of grassland arthropod abundance | GLOBAL ECOLOGY AND BIOGEOGRAPHY, 29(12), 2273-2288. | 10.1111/geb.13196 |
Ref8 | Ros, MBH; Koopmans, GF; van Groenigen, KJ; Abalos, D; Oenema, O; Vos, HMJ; van Groenigen, JW | 2020 | Towards optimal use of phosphorus fertiliser | SCIENTIFIC REPORTS, 10, 17804. | 10.1038/s41598-020-74736-z |
Ref9 | Wang, C; Tang, YJ; Li, XN; Zhang, WW; Zhao, CQ; Li, C | 2020 | Negative impacts of plant diversity loss on carbon sequestration exacerbate over time in grasslands | ENVIRONMENTAL RESEARCH LETTERS, 15(10), 104055. | 10.1088/1748-9326/abaf88 |
Ref10 | Xu, S; Eisenhauer, N; Ferlian, O; Zhang, JL; Zhou, GY; Lu, XK; Liu, CS; Zhang, DQ | 2020 | Species richness promotes ecosystem carbon storage: Evidence from biodiversity-ecosystem functioning experiments | PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES, 287, 20202063. | 10.1098/rspb.2020.2063 |
Ref11 | Zhang, LH; Yuan, FH; Bai, JH; Duan, HT; Gu, XY; Hou, LY; Huang, Y; Yang, MG; He, JS; Zhang, ZH; Yu, LJ; Song, CC; Lipson, DA; Zona, D; Oechel, W; Janssens, IA; Xu, XF | 2020 | Phosphorus alleviation of nitrogen-suppressed methane sink in global grasslands | ECOLOGY LETTERS, 23(5), 821-830. | 10.1111/ele.13480 |
Ref12 | Chen, C; Chen, HYH; Chen, XL; Huang, ZQ | 2019 | Meta-analysis shows positive effects of plant diversity on microbial biomass and respiration | NATURE COMMUNICATIONS, 10, 1332. | 10.1038/s41467-019-09258-y |
Ref13 | Gravuer, K; Gennet, S; Throop, HL | 2019 | Organic amendment additions to rangelands: A meta-analysis of multiple ecosystem outcomes | GLOBAL CHANGE BIOLOGY, 25[3), 1152-1170. | 10.1111/gcb.14535 |
Ref14 | Jiang, J; Wang, YP; Yang, YH; Yu, MX; Wang, C; Yan, JH | 2019 | Interactive effects of nitrogen and phosphorus additions on plant growth vary with ecosystem type | PLANT AND SOIL, 440(1-2), 523-537. | 10.1007/s11104-019-04119-5 |
Ref15 | Midolo, G; Alkemade, R; Schipper, AM; Benitez-Lopez, A; Perring, MP; De Vries, W | 2019 | Impacts of nitrogen addition on plant species richness and abundance: A global meta-analysis | GLOBAL ECOLOGY AND BIOGEOGRAPHY, 28(3), 398-413. | 10.1111/geb.12856 |
Ref16 | Zheng, MH; Zhou, ZH; Luo, YQ; Zhao, P; Mo, JM | 2019 | Global pattern and controls of biological nitrogen fixation under nutrient enrichment: A meta-analysis | GLOBAL CHANGE BIOLOGY, 25(9), 3018-3030. | 10.1111/gcb.14705 |
Ref17 | Talle, M; Deak, B; Poschlod, P; Valko, O; Westerberg, L; Milberg, P | 2018 | Similar effects of different mowing frequencies on the conservation value of semi-natural grasslands in Europe | BIODIVERSITY AND CONSERVATION, 27(10), 2451-2475. | 10.1007/s10531-018-1562-6 |
Ref18 | Wang, JY; Chadwick, DR; Cheng, Y; Yan, XY | 2018 | Global analysis of agricultural soil denitrification in response to fertilizer nitrogen | SCIENCE OF THE TOTAL ENVIRONMENT, 616, 908-917. | 10.1016/j.scitotenv.2017.10.229 |
Ref19 | Cai, YJ; Akiyama, H | 2017 | Effects of inhibitors and biochar on nitrous oxide emissions, nitrate leaching, and plant nitrogen uptake from urine patches of grazing animals on grasslands: A meta-analysis | SOIL SCIENCE AND PLANT NUTRITION, 63(4), 405-414. | 10.1080/00380768.2017.1367627 |
Ref20 | Chen, J; Luo, YQ; Li, JW; Zhou, XH; Cao, JJ; Wang, RW; Wang, YQ; Shelton, S; Jin, Z; Walker, LM; Feng, ZZ; Niu, SL; Feng, WT; Jian, SY; Zhou, LY | 2017 | Costimulation of soil glycosidase activity and soil respiration by nitrogen addition | GLOBAL CHANGE BIOLOGY, 23(3), 1328-1337. | 10.1111/gcb.13402 |
Ref21 | You, CM; Wu, FZ; Gan, YM; Yang, WQ; Hu, ZM; Xu, ZF; Tan, B; Liu, L; Ni, XY | 2017 | Grass and forbs respond differently to nitrogen addition: A meta-analysis of global grassland ecosystems | SCIENTIFIC REPORTS, 7, 1563. | 10.1038/s41598-017-01728-x |
Ref22 | Zhou, ZH; Wang, CK; Zheng, MH; Jiang, LF; Luo, YQ | 2017 | Patterns and mechanisms of responses by soil microbial communities to nitrogen addition | SOIL BIOLOGY AND BIOCHEMISTRY, 115, 433-441. | 10.1016/j.soilbio.2017.09.015 |
Ref23 | Geisseler, D; Lazicki, PA; Scow, KM | 2016 | Mineral nitrogen input decreases microbial biomass in soils under grasslands but not annual crops | APPLIED SOIL ECOLOGY, 106, 1-10. | 10.1016/j.apsoil.2016.04.015 |
Ref24 | Gilsanz, C; Baez, D; Misselbrook, TH; Dhanoa, MS; Cardenas, LM | 2016 | Development of emission factors and efficiency of two nitrification inhibitors, DCD and DMPP | AGRICULTURE ECOSYSTEMS AND ENVIRONMENT, 216, 1-8. | 10.1016/j.agee.2015.09.030 |
Ref25 | Humbert, JY; Dwyer, JM; Andrey, A; Arlettaz, R | 2016 | Impacts of nitrogen addition on plant biodiversity in mountain grasslands depend on dose, application duration and climate: A systematic review | GLOBAL CHANGE BIOLOGY, 22(1), 110-120. | 10.1111/gcb.12986 |
Ref26 | Li, Y; Niu, SL; Yu, GR | 2016 | Aggravated phosphorus limitation on biomass production under increasing nitrogen loading: A meta-analysis | GLOBAL CHANGE BIOLOGY, 22(2), 934-943. | 10.1111/gcb.13125 |
Ref27 | Talle, M; Deak, B; Poschlod, P; Valko, O; Westerberg, L; Milberg, P | 2016 | Grazing vs. mowing: A meta-analysis of biodiversity benefits for grassland management | AGRICULTURE ECOSYSTEMS AND ENVIRONMENT, 222, 200-212. | 10.1016/j.agee.2016.02.008 |
Ref28 | Tian, DH; Wang, H; Sun, J; Niu, SL | 2016 | Global evidence on nitrogen saturation of terrestrial ecosystem net primary productivity | ENVIRONMENTAL RESEARCH LETTERS, 11(2), 24012. | 10.1088/1748-9326/11/2/024012 |
Ref29 | Thakur, MP; Milcu, A; Manning, P; Niklaus, PA; Roscher, C; Power, S; Reich, PB; Scheu, S; Tilman, D; Ai, F; Guo, H; Ji, R; Pierce, S; Ramirez, NG; Richter, AN; Steinauer, K; Strecker, T; Vogel, A; Eisenhauer, N | 2015 | Plant diversity drives soil microbial biomass carbon in grasslands irrespective of global environmental change factors | GLOBAL CHANGE BIOLOGY, 21(11), 4076-4085. | 10.1111/gcb.13011 |
Ref30 | Humbert, JY; Pellet, J; Buri, P; Arlettaz, R | 2012 | Does delaying the first mowing date benefit biodiversity in meadowland? | ENVIRONMENTAL EVIDENCE, 1, 9. | 10.1186/2047-2382-1-9 |
Ref31 | Kim, DG; Saggar, S; Roudier, P | 2012 | The effect of nitrification inhibitors on soil ammonia emissions in nitrogen managed soils: A meta-analysis | NUTRIENT CYCLING IN AGROECOSYSTEMS, 93(1), 51-64. | 10.1007/s10705-012-9498-9 |
Ref32 | De Schrijver, A; De Frenne, P; Ampoorter, E; Van Nevel, L; Demey, A; Wuyts, K; Verheyen, K | 2011 | Cumulative nitrogen input drives species loss in terrestrial ecosystems | GLOBAL ECOLOGY AND BIOGEOGRAPHY, 20(6), 803-816. | 10.1111/j.1466-8238.2011.00652.x |
Ref33 | Akiyama, H; Yan, XY; Yagi, K | 2010 | Evaluation of effectiveness of enhanced-efficiency fertilizers as mitigation options for N2O and NO emissions from agricultural soils: Meta-analysis | GLOBAL CHANGE BIOLOGY, 16(6) 1837-1846. | 10.1111/j.1365-2486.2009.02031.x |
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.
[2] https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Glossary:Shrubland
[3] https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Glossary:Grassland
[4] Diacono, M, and Montemurro, F. 2010. Long‐term effects of organic amendments on soil fertility. A review. Agronomy for Sustainable Development, 30, 401–422.
[5] Li, T ; Zhang, W ; Yin, J ; et al. 2018. Enhanced‐efficiency fertilizers are not a panacea for resolving the nitrogen problem. Global Change Biology, 24, e511– e521.
[6] https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Glossary:Fertiliser
[7] Velthof, GL; Lesschen, JP; Schils, RLM; et al. 2014. Grassland areas, production and use. Methodological studies in the field of Agro-Environmental Indicators. Alterra, Wageningen.