Net methane emissions from grazing sheep

Summary Methane emissions from ruminant livestock are responsible for 45 % of New Zealand’s combined CO2‐equivalent greenhouse gas inventory, and arise principally from sheep. Using a flock of 6‐month old sheep (20 ha–1) grazing abundant pasture, we compare micrometeorological measurements of net me...

Full description

Saved in:
Bibliographic Details
Published in:Global change biology 1999-08, Vol.5 (6), p.647-657
Main Authors: Judd, M.J, Kellier, F.M, Ulyatt, M.J, Lassey, K.R, Tate, K.R, Shelton, I.D, Harvey, M.J, Walker, C.F
Format: Article
Language:English
Subjects:
age
ambient temperature
body weight
diurnal variation
emissions
energy expenditure
feed intake
grazing
meteorological data
methane
methane production
microclimate
micrometeorology
New Zealand
oxidation
pastures
sheep
soil chemistry
soil-oxidation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Summary Methane emissions from ruminant livestock are responsible for 45 % of New Zealand’s combined CO2‐equivalent greenhouse gas inventory, and arise principally from sheep. Using a flock of 6‐month old sheep (20 ha–1) grazing abundant pasture, we compare micrometeorological measurements of net methane emission rates with measurements from individual sheep based on a sulphur‐hexafluoride tracer technique. Individual sheep emission rates were highly variable and averaged 19.5 ± 4.8 (SD) g CH4 sheep–1 d–1, or 39 ± 9.6 mg CH4 m–2 d–1 on an areal basis. Emission rates were poorly correlated with animal live weight or dry matter intake but represented an average dietary energy loss of 3.6%.  Methane fluxes from the surface were determined as half hourly averages by a flux‐gradient technique using temperature and methane gradients. Soil methane consumption was measured using chambers and found to be negligible (
ISSN:1354-1013
1365-2486
DOI:10.1046/j.1365-2486.1999.00264.x