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Data extracted in September 2021
Fiche created in February 2024
Note to the reader: This general fiche summarises all the environmental and climate impacts of CROP ROTATION found in a review of 17 synthesis papers[1]. These papers were selected from an initial number of 249 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 3 to 122. 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:
- Crop rotation on arable land is the practice of alternating crops grown on a specific field in a planned pattern or sequence in successive crop years, so that crops of the same species are not grown without interruption on the same field. In a rotation, the crops are normally changed annually, but they can also be multi-annual. If the same crop is grown continuously, the term monoculture can be used to describe the phenomenon[2].
- Key descriptors:
- This review includes three types of crop rotation comparisons2: (i) rotations of two crops compared to monocropping[3] (in 10 synthesis papers), (ii) rotations of 3 or more crops compared to monocropping (in 2 synthesis papers), and (iii) rotations of 3 or more crops compared to crop rotation of two crops (in 2 synthesis papers). Seven synthesis papers did not clearly specify the type of rotation (more diverse rotations vs. monocropping or 2-crop rotation).
- This review does not include synthesis research papers that study the primary effects of: (i) cover crops - plants that are cultivated to cover (and protect) the soil instead of being harvested (i.e., studies where cover crops were only present in the intervention group and not in the control, were excluded), (ii) break crops - alternative crops to interrupt the repeated sowing of a cash crop, and (iii) fallowing - leave the arable land without planting for at least one year. The direct impacts of these three practices are evaluated in separate sets of fiches.
2. EFFECTS OF THE FARMING PRACTICE ON CLIMATE AND ENVIRONMENTAL IMPACTS
We reviewed the impacts of more diverse rotation (with two or more crops) compared to monocropping or simpler rotations. (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 17 selected synthesis papers, 8 included studies conducted in Europe, and 15 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.
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| Statistically tested | Non-statistically tested | ||
Impact | Metric | Intervention | Comparator | Significantly positive | Significantly negative | Non-significant | |
Increase Carbon sequestration | Carbon sequestration | Diversified rotation | Simplified rotation | 5 (3) | 1 | 5 (4) | 0 |
Decrease GHG emissions | GHG emissions | Diversified rotation | Simplified rotation | 0 | 0 | 2 | 0 |
Global warming potential (LCA) | Global warming potential (LCA) | Diversified rotation | Simplified rotation | 1 | 1 | 0 | 0 |
Increase Pests and diseases | Weed biomass and density | Diversified rotation | Simplified rotation | 1 | 0 | 1 | 0 |
Increase Soil biological quality | Soil biological quality | Diversified rotation | Simplified rotation | 4 | 0 | 2 | 0 |
Increase Soil nutrients | Soil nutrients | Diversified rotation | Simplified rotation | 2 | 0 | 0 | 0 |
Increase Crop yield | Crop yield | Diversified rotation | Simplified rotation | 3 | 0 | 1 | 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 |
Carbon sequestration | Climate (Ref14), Cover crop in the rotation (Ref14), Crop type (Ref6, Ref14), Duration of treatment (Ref1), Elevation (Ref6), Latitude (Ref6), N application rate (Ref6), Number of crops in the rotation (Ref14, Ref17), Site-level SOC concentration (Ref6), Soil depth (Ref15) and Tillage (Ref17) |
GHG emissions | N application rates (Ref13), |
Global warming potential (LCA) | Climate (Ref10), Duration of experiment (Ref10) and Soil texture (Ref10) |
Pests and diseases | Temporal variance around crop planting dates (Ref4), Tillage (Ref4) and Weed measurement unit (Ref4) |
Soil biological quality | Climate (Ref14), Duration of experiment (Ref2, Ref11), Microbial analysis method (Ref11), Soil texture (Ref14), Soil texture and soil type (Ref2) and Trophic level (Ref2) |
Soil nutrients | Cover crop in the rotation (Ref14), Number of crops in the rotation (Ref7 and Ref14) |
Crop yield | Climate (Ref3), Crop type (Ref3), Geographical area (Ref3), Mineral N fertiliser application rate (Ref3, Ref9), Number of rotation cycle (Ref3), Rotation system (Ref3), Soil characteristics (Ref3) and Tillage (Ref3) |
4. SYSTEMATIC REVIEW SEARCH STRATEGY
Table 3: Systematic review search strategy - methodology and search parameters.
Parameter | Details |
Keywords | WOS: TOPIC: (( crop* near/3 rotat* ) OR ( crop* near/3 sequen* ) OR ( cultiv* near/3 rotat* ) OR ( cultiv* near/3 sequen* ) OR ( multi* near/3 crop* ) OR ( multi* near/3 cultiv* ) OR ( crop* near/3 divers* ) OR ( cultiv* near/3 divers* )) AND TOPIC: (("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 01 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 | Audette, Y; Congreves, KA; Schneider, K; Zaro, GC; Nunes, ALP; Zhang, HJ; Voroney, RP | 2021 | The effect of agroecosystem management on the distribution of C functional groups in soil organic matter: A review | BIOL FERTIL SOILS, 57, 881–894. | 10.1007/s00374-021-01580-2 |
Ref2 | Puissant, J; Villenave, C; Chauvin, C; Plassard, C; Blanchart, E; Trap, J | 2021 | Quantification of the global impact of agricultural practices on soil nematodes: A meta-analysis | SOIL BIOL BIOCHEM, 161, 108383 | 10.1016/j.soilbio.2021.108383 |
Ref3 | Zhao, J; Yang, YD; Zhang, K; Jeong, J; Zeng, ZH; Zang, HD | 2020 | Does crop rotation yield more in China? A meta-analysis | FIELD CROPS RES, 245, 107659 | 10.1016/j.fcr.2019.107659 |
Ref4 | Weisberger, D; Nichols, V; Liebman, M | 2019 | Does diversifying crop rotations suppress weeds? A meta-analysis | PLOS ONE, 14, e0219847 | 10.1371/journal.pone.0219847 |
Ref5 | Assefa, Y; Prasad, PVV; Foster, C; Wright, Y; Young, S; Bradley, P; Stamm, M; Ciampitti, IA | 2018 | Major management factors determining spring and winter canola yield in North America | CROP SCI, 58, 1-16. | 10.2135/cropsci2017.02.0079 |
Ref6 | King, AE; Blesh, J | 2018 | Crop rotations for increased soil carbon: perenniality as a guiding principle | ECOL APPL, 28, 249-261. | 10.1002/eap.1648 |
Ref7 | Mahal, NK; Castellano, MJ; Miguez, FE | 2018 | Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis | SOIL SCI SOC AM J, 82, 1270–1278 | 10.2136/sssaj2017.07.0245 |
Ref8 | Han, Zhen; Walter, M. Todd; Drinkwater, Laurie E. | 2017 | N2O emissions from grain cropping systems: a meta-analysis of the impacts of fertilizer-based and ecologically-based nutrient management strategies | NUTR CYCLING AGROECOSYST, 107, 335-355 | 10.1007/s10705-017-9836-z |
Ref9 | Ma B.-L., Wu W. | 2016 | Crop productivity and environment impact in a maize-legume rotation system: A review | Crop rotations: farming practices, monitoring and environmental benefits. Nova Science Publisher Inc, New York, 1-33 | ISBN: 978-1-63484-496-3 |
Ref10 | Sainju, UM | 2016 | A Global Meta-Analysis on the Impact of Management Practices on Net Global Warming Potential and Greenhouse Gas Intensity from Cropland Soils | PLOS ONE, 11, e0148527 | 10.1371/journal.pone.0148527 |
Ref11 | Venter, ZS; Jacobs, K; Hawkins, HJ | 2016 | The impact of crop rotation on soil microbial diversity: A meta-analysis | PEDOBIOLOGIA, 59, 215-223 | 10.1016/j.pedobi.2016.04.001 |
Ref12 | Congreves, KA; Smith, JM; Nemeth, DD; Hooker, DC; Van Eerd, LL | 2014 | Soil organic carbon and land use: Processes and potential in Ontario's long-term agro-ecosystem research sites | CAN J SOIL SCI, 94, 317-336 | 10.4141/CJSS2013-094 |
Ref13 | Decock C | 2014 | Mitigating Nitrous Oxide Emissions from Corn Cropping Systems in the Midwestern US: Potential and Data Gaps | ENVIRON SCI TECHNOL 48, 4247–4256 | 10.1021/es4055324 |
Ref14 | McDaniel, MD; Tiemann, LK; Grandy, AS | 2014 | Does agricultural crop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis | ECOL APPL, 24, 560–570 | 10.1890/13-0616.1 |
Ref15 | Ugarte, CM; Kwon, H; Andrews, SS; Wander, MM | 2014 | A meta-analysis of soil organic matter response to soil management practices: An approach to evaluate conservation indicators | J SOIL WATER CONSERV, 69, 422-430 | 10.2489/jswc.69.5.422 |
Ref16 | Lekberg, Y; Koide, RT | 2005 | Is plant performance limited by abundance of arbuscular mycorrhizal fungi? A meta-analysis of studies published between 1988 and 2003 | NEW PHYTOL, 168, 189-204. | 10.1111/j.1469-8137.2005.01490.x |
Ref17 | West, TO; Post, WM | 2002 | Soil organic carbon sequestration rates by tillage and crop rotation: A global data analysis | SOIL SCI SOC AM J, 66, 1930-1946 | 10.2136/sssaj2002.1930 |
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] Eurostat. https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Glossary:Crop_rotation.
[3] Monocropping is the continuous growing of the same species on a piece of land over a sequence of growing seasons (C.A. Francis, P. Porter, in Encyclopedia of Applied Plant Sciences (Second Edition), 2017..