Elucidating three-way interactions between soil, pasture and animals that regulate nitrous oxide emissions from temperate grazing systems

A - Papers appearing in refereed journals

McAuliffe, G., Lopez, M., Blackwell, M. S. A., Castellano-Hinojosa, A., Darch, T., Evans, J., Horrocks, C. A., Le Cocq, K., Takahashi, T., Harris, P., Lee, M. R. F. and Cardenas, L. M. 2020. Elucidating three-way interactions between soil, pasture and animals that regulate nitrous oxide emissions from temperate grazing systems. Agriculture, Ecosystems & Environment. 300, p. 106978.

AuthorsMcAuliffe, G., Lopez, M., Blackwell, M. S. A., Castellano-Hinojosa, A., Darch, T., Evans, J., Horrocks, C. A., Le Cocq, K., Takahashi, T., Harris, P., Lee, M. R. F. and Cardenas, L. M.
Abstract

Pasture-based livestock farming contributes considerably to global emissions of nitrous oxide (N2O), a powerful greenhouse gas approximately 265 times more potent than carbon dioxide. Traditionally, the estimation of N2O emissions from grasslands is carried out by means of plot-scale experiments, where externally sourced animal excreta are applied to soils to simulate grazing conditions. This approach, however, fails to account for the impact of different sward types on the composition of excreta and thus the functionality of soil microbiomes, creating unrealistic situations that are seldom observed under commercial agriculture. Using three farming systems employing contrasting pasture management strategies at the North Wyke Farm Platform, an instrumented ruminant grazing trial in Devon, UK, this study measured N2O emissions from soils treated with cattle urine and dung collected within each system as well as standard synthetic urine shared across all systems, and compared them against two forms of controls with and without inorganic nitrogen fertiliser applications. Soil microbial activity was regularly monitored through gene abundance to evaluate interactions between sward types, soil amendments, soil microbiomes and, ultimately, N2O production. Across all systems, N2O emissions attributable to cattle urine and standard synthetic urine were found to be inconsistent with one another due to discrepancy in nitrogen content. Despite previous findings that grasses with elevated levels of water-soluble carbohydrates tend to generate lower levels of N2O, the soil under high sugar grass monoculture in this study recorded higher emissions when receiving excreta from cattle fed the same grass. Combined together, our results demonstrate the importance of evaluating environmental impacts of agriculture at a system scale, so that the feedback mechanisms linking soil, pasture, animals and microbiomes are appropriately considered.

KeywordsNitrous oxide ; Beef cattel; Urine; Dung; Climate change; Denitrification; Nitrification; Soil microbial communities
Year of Publication2020
JournalAgriculture, Ecosystems & Environment
Journal citation300, p. 106978
Digital Object Identifier (DOI)doi:10.1016/j.agee.2020.106978
Open accessPublished as ‘gold’ (paid) open access
FunderBiotechnology and Biological Sciences Research Council
Agriculture and Horticulture Development Board
Funder project or codeS2N - Soil to Nutrition - Work package 2 (WP2) - Adaptive management systems for improved efficiency and nutritional quality
The North Wyke Farm Platform- National Capability [2017-22]
7795
Publisher's version
Output statusPublished
Publication dates
Online27 Apr 2020
Publication process dates
Accepted24 Apr 2020
PublisherElsevier Science Bv
ISSN0167-8809

Permalink - https://repository.rothamsted.ac.uk/item/97q80/elucidating-three-way-interactions-between-soil-pasture-and-animals-that-regulate-nitrous-oxide-emissions-from-temperate-grazing-systems

3 total views
1 total downloads
1 views this month
1 downloads this month
Download files as zip