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Agriculture is the largest single source of global anthropogenic methane (CH 4 ) emissions, with ruminants the dominant contributor. Livestock CH 4 emissions are projected to grow another 30% by 2050 under current policies, yet few countries have set targets or are implementing policies to reduce emissions in absolute terms. The reason for this limited ambition may be linked not only to the underpinning role of livestock for nutrition and livelihoods in many countries but also diverging perspectives on the importance of mitigating these emissions, given the short atmospheric lifetime of CH 4 . Here, we show that in mitigation pathways that limit warming to 1.5°C, which include cost-effective reductions from all emission sources, the contribution of future livestock CH 4 emissions to global warming in 2050 is about one-third of that from future net carbon dioxide emissions. Future livestock CH 4 emissions, therefore, significantly constrain the remaining carbon budget and the ability to meet stringent temperature limits. We review options to address livestock CH 4 emissions through more efficient production, technological advances and demand-side changes, and their interactions with land-based carbon sequestration. We conclude that bringing livestock into mainstream mitigation policies, while recognizing their unique social, cultural and economic roles, would make an important contribution towards reaching the temperature goal of the Paris Agreement and is vital for a limit of 1.5°C. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 1)'.

Soil structure forms a key component of soil quality, and its assessment by semi‐quantitative visual soil evaluation (VSE) techniques can help scientists, advisors and farmers make decisions regarding sampling and soil management. VSE techniques require inexpensive equipment and generate immediate results that correlate well with quantitative measurements of physical and biochemical properties, highlighting their potential utility. We reviewed published VSE techniques and found that soils of certain textures present problems and a lack of research into the influence of soil moisture content on VSE criteria. Generally, profile methods evaluate process interactions at specific locations within a field, exploring both intrinsic aspects and anthropogenic impacts. Spade methods focus on anthropogenic characteristics, providing rapid synopses of soil structure over wider areas. Despite a focus on structural form, some methods include criteria related to stability and resiliency. Further work is needed to improve existing methods regarding texture influences, on‐farm sampling procedures and more holistic assessments of soil structure.

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Visual evaluation of soil structure (VESS) is used for assessing arable management impact on soil quality. When used on pastures, operators have identified limitations because VESS does not consider a surface root‐mat typical of managed grassland. The structure of the root‐mat may be indicative of nutrient use efficiency, pollution potential and subsurface compaction. The objectives of this research were to develop GrassVESS for grassland soil management, to compare it with VESS and quantitative physical indicators and to assess its utility for soil management. GrassVESS maintained the methodological strengths of VESS, but uses a flow chart, grassland images and a new root‐mat score. A focus group found GrassVESS to be quicker, dealt better with technical information and made root‐mat evaluation easier. The range of structural quality scores assigned by the focus group for a site was less for GrassVESS than VESS, suggesting the procedure is more reproducible, thus suitable for use by a range of stakeholders. GrassVESS was also deployed at 30 grassland sites across Ireland. Results indicated that GrassVESS generated the same overall diagnoses as VESS, but the GrassVESS root‐mat structural quality score was better related to bulk density, total porosity at 5–10 cm and a visual estimation of damaged sward area. It was concluded that GrassVESS has improved the VESS method for the specific assessment of grassland soil structural quality and could be used in real‐time farm management decision support.