Agriculture Reference
In-Depth Information
Table 15.2.
Examples of methane emissions from different manure storage measured using different
technologies. Emissions unde
r the same study are direct co
mparisons of techn
iques.
Methane emission
(g m
−
2
day
−
1
)
Manure management
Technology
Study
Beef feedlot
0-27 (active aeration)
NSS
Hao
et al
. (2001)
Compost pile
0-54 (passive aeration)
Dairy wastewater
and pen runoff
103
BLS
Leytem
et al
. (2011)
Dairy wastewater
and pen runoff
40
BLS
Todd
et al
. (2011)
Dairy lagoon
16
Biogas production
Craggs
et al
. (2008)
≈
Swine lagoon
416
Biogas production
Craggs
et al
. (2008)
≈
Swine lagoon
143
MB
Park
et al
. (2010)
205
FT-SS
NSS, non-steady-state; BLS, backward-time Lagrangian stochastic; MB, mass balance; FT-SS, flow-through steady-
state.
≈
, Preceding values indicates units were converted for use in this table using the ideal gas law
Table 15.3.
Examples of ammonia emissions from different manure storage measured using different
technologies.
Ammonia emission
(g m
−
2
day
−
1
)
Manure management
Technology
Study
Beef feedlot
3-6
FG
Todd
et al
. (2005)
Beef feedlot
8-9
BLS
Flesch
et al
. (2007)
Beef feedlot
1-7 (different feedlots)
BLS
Denmead
et al
. (2008)
Beef cattle manure
on grass sward
0.012-0.036
MB
Salomon and Rodhe
(2011)
Fresh feedlot manure
12-16 (different diets)
FT-SS
McGinn
et al
. (2002)
Dairy lagoon
5
BLS
McGinn
et al
. (2008b)
Swine lagoon
1.1-1.8 (different lagoons)
FG
Harper
et al
. (2004)
Swine slurry on short grass
4
TPS
Gordon
et al
. (1988)
BLS, backward-time Lagrangian stochastic; FG, flux gradient; EC, eddy covariance; FT-SS, flow-through steady-state;
MB, mass balance; TPS, theoretical profile shape.
Although some methodology standards
have been developed for specific monitoring
programmes, e.g. the US National Air Emis-
sions Monitoring Study (Heber
et al
., 2008), the
majority of emission studies are independent
where the protocol for determining emissions
is unique to each case. It follows that the
comparison of studies can be confounded by
instrumentation, emission theory and data
management. It is therefore important to revisit
the emissions techniques for NH
3
and CH
4
and
report comparisons on the derived emissions.
(NSS) design monitors the build-up of the gas
inside the chamber over time. In the steady-state
(SS) design, the gas inside the chamber is in
equilibrium with the source emission. There are
two types of SS enclosures, the flow-through
(FT-SS) and non-flow-through (NFT-SS) type.
The FT-SS design relies on fresh air being drawn
through the enclosure where there is no build-
up of the gas inside the enclosure. The NFT-SS
design has a scrubber associated with the
chamber that removes the target gas.
All these enclosures can be used to measure
enteric CH
4
from livestock or CH
4
and NH
3
from
livestock manure. In the case of whole-animal
CH
4
chamber measurements, most common is
the FT-SS design, e.g. Grainger
et al
. (2007).
However, some of the earlier work measuring
CH
4
emission from livestock (Turner and
Chamber techniques
There are two general designs of enclosures used
to measure gas exchange. The non-steady-state
