Cover crops play an increasingly important role in improving soil quality, reducing agricultural inputs and improving environmental sustainability. The main objectives of this critical global review and systematic analysis were to assess cover crop practices in the context of their impacts on nitrogen leaching, net greenhouse gas balances (NGHGB) and crop productivity. Only studies that investigated the impacts of cover crops and measured one or a combination of nitrogen leaching, soil organic carbon (SOC), nitrous oxide (N2O), grain yield and nitrogen in grain of primary crop, and had a control treatment were included in the analysis. Long\uffe2\uff80\uff90term studies were uncommon, with most data coming from studies lasting 2\uffe2\uff80\uff933\uffc2\uffa0years. The literature search resulted in 106 studies carried out at 372 sites and covering different countries, climatic zones and management. Our analysis demonstrates that cover crops significantly (p\uffc2\uffa0<\uffc2\uffa00.001) decreased N leaching and significantly (p\uffc2\uffa0<\uffc2\uffa00.001) increased SOC sequestration without having significant (p\uffc2\uffa0>\uffc2\uffa00.05) effects on direct N2O emissions. Cover crops could mitigate the NGHGB by 2.06\uffc2\uffa0\uffc2\uffb1\uffc2\uffa02.10\uffc2\uffa0Mg CO2\uffe2\uff80\uff90eq\uffc2\uffa0ha\uffe2\uff88\uff921\uffc2\uffa0year\uffe2\uff88\uff921. One of the potential disadvantages of cover crops identified was the reduction in grain yield of the primary crop by \uffe2\uff89\uff884%, compared to the control treatment. This drawback could be avoided by selecting mixed cover crops with a range of legumes and non\uffe2\uff80\uff90legumes, which increased the yield by \uffe2\uff89\uff8813%. These advantages of cover crops justify their widespread adoption. However, management practices in relation to cover crops will need to be adapted to specific soil, management and regional climatic conditions.
", "keywords": ["Crops", " Agricultural", "net greenhouse gas balance", "330", "Supplementary Data", "Nitrogen", "QH301 Biology", "Supplementary data available", "12. Responsible consumption", "Nitrous oxide emissions", "QH301", "Greenhouse Gases", "Soil", "N content", "nitrate", "C sequestration", "N leaching", "Environmental Chemistry", "General Environmental Science", "NE/M019691/1", "2. Zero hunger", "Global and Planetary Change", "Catch crop", "Ecology", "Soil organic carbon", "green manure", "Natural Environment Research Council (NERC)", "Research Review", "Agriculture", "04 agricultural and veterinary sciences", "15. Life on land", "yield", "Crop Production", "13. Climate action", "N in grain", "Biotechnology and Biological Sciences Research Council (BBSRC)", "Cover crop", "0401 agriculture", " forestry", " and fisheries", "BB/N013484/1", "BB/N013468/1"]}, "links": [{"href": "https://doi.org/10.1111/gcb.14644"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Global%20Change%20Biology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/gcb.14644", "name": "item", "description": "10.1111/gcb.14644", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/gcb.14644"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-05-13T00:00:00Z"}}, {"id": "10.1111/nph.15516", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-07-28T16:19:00Z", "type": "Journal Article", "created": "2018-10-06", "title": "Imaging microstructure of the barley rhizosphere: particle packing and root hair influences", "description": "Summary
Soil adjacent to roots has distinct structural and physical properties from bulk soil, affecting water and solute acquisition by plants. Detailed knowledge on how root activity and traits such as root hairs affect the three\uffe2\uff80\uff90dimensional pore structure at a fine scale is scarce and often contradictory.
Roots of hairless barley (Hordeum vulgare L. cv Optic) mutant (NRH) and its wildtype (WT) parent were grown in tubes of sieved (<250\uffc2\uffa0\uffce\uffbcm) sandy loam soil under two different water regimes. The tubes were scanned by synchrotron\uffe2\uff80\uff90based X\uffe2\uff80\uff90ray computed tomography to visualise pore structure at the soil\uffe2\uff80\uff93root interface. Pore volume fraction and pore size distribution were analysed vs distance within 1\uffc2\uffa0mm of the root surface.
Less dense packing of particles at the root surface was hypothesised to cause the observed increased pore volume fraction immediately next to the epidermis. The pore size distribution was narrower due to a decreased fraction of larger pores. There were no statistically significant differences in pore structure between genotypes or moisture conditions.
A model is proposed that describes the variation in porosity near roots taking into account soil compaction and the surface effect at the root surface.
", "keywords": ["name=Physiology", "STABILIZATION", "Physiology", "EP/M020355/1", "Supplementary Data", "QH301 Biology", "Plant Science", "Supplementary data available", "Plant Roots", "630", "noninvasive imaging", "Soil", "646809DIMR", "STRENGTH", "BB/J00868/1", "Hordeum vulgare", "2. Zero hunger", "04 agricultural and veterinary sciences", "Rhizosphere", "COMPRESSION", "soil structure", "Porosity", "European Research Council", "/dk/atira/pure/subjectarea/asjc/1300/1314", "/dk/atira/pure/subjectarea/asjc/1100/1110", "root hairs", "COMPACTION", "QH301", "Imaging", " Three-Dimensional", "synchrotron", "particle packing", "SOIL-STRUCTURE", "BB/L025620/1", "WATER-STRESS", "NE/L00237/1", "580", "ELONGATION", "Civil_env_eng", "Natural Environment Research Council (NERC)", "POROSITY", "Water", "Hordeum", "15. Life on land", "Engineering and Physical Sciences Research Council (EPSRC)", "Mutation", "Biotechnology and Biological Sciences Research Council (BBSRC)", "0401 agriculture", " forestry", " and fisheries", "PENETRATION", "name=Plant Science", "rhizosphere", "Tomography", " X-Ray Computed", "MAIZE", "BB/P004180/1", "Synchrotrons", "BB/L025825/1"]}, "links": [{"href": "https://repository.uwl.ac.uk/id/eprint/5489/1/AS6808504337817661539338801587_content_1.pdf"}, {"href": "https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/nph.15516"}, {"href": "https://doi.org/10.1111/nph.15516"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/New%20Phytologist", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/nph.15516", "name": "item", "description": "10.1111/nph.15516", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/nph.15516"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-11-20T00:00:00Z"}}, {"id": "2164/11950", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-07-28T16:24:38Z", "type": "Journal Article", "created": "2018-10-06", "title": "Imaging microstructure of the barley rhizosphere: particle packing and root hair influences", "description": "Summary
Soil adjacent to roots has distinct structural and physical properties from bulk soil, affecting water and solute acquisition by plants. Detailed knowledge on how root activity and traits such as root hairs affect the three\uffe2\uff80\uff90dimensional pore structure at a fine scale is scarce and often contradictory.
Roots of hairless barley (Hordeum vulgare L. cv Optic) mutant (NRH) and its wildtype (WT) parent were grown in tubes of sieved (<250\uffc2\uffa0\uffce\uffbcm) sandy loam soil under two different water regimes. The tubes were scanned by synchrotron\uffe2\uff80\uff90based X\uffe2\uff80\uff90ray computed tomography to visualise pore structure at the soil\uffe2\uff80\uff93root interface. Pore volume fraction and pore size distribution were analysed vs distance within 1\uffc2\uffa0mm of the root surface.
Less dense packing of particles at the root surface was hypothesised to cause the observed increased pore volume fraction immediately next to the epidermis. The pore size distribution was narrower due to a decreased fraction of larger pores. There were no statistically significant differences in pore structure between genotypes or moisture conditions.
A model is proposed that describes the variation in porosity near roots taking into account soil compaction and the surface effect at the root surface.