can we reduce nitrous oxide emissions from animal production systems - kevin kelly
DESCRIPTION
TRANSCRIPT
Can we reduce nitrous oxide emissions from animal production systems?
Kevin Kelly, Graeme Ward, Sally Officer, Tim Huggins, Richard Eckard
Agricultural soils - nitrous oxide emissions
(DCCEE 2010)
0
1
2
3
4
Nit
rou
s o
xid
e (M
t C
O2e
)
Background
Nitrogen excreted at grazing, major contributor to N2O emissions.
NZ research with inhibitors has demonstrated - up to 70% reduction in direct emissions, and- reduction in nitrate leaching (indirect emissions)- 0-30% increases in pasture production
Aust. research demonstrated potential for 25-50% reduction
Project FocusEmissions from urine patches
Dicyandiamide (DCD) applied to pasture/soils
Gas measurements pasture measurements
Why a dairy system? stocking intensities are high generally in high rainfall zones
TerangSW Victoria
Daily nitrous oxide flux and soil water
0
40
80
120
160
200
240
Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10
Flu
x (g
N2O
-N/h
a/d
)
-
0.10
0.20
0.30
0.40
0.50
0.60
So
il w
ater
(m
m3/
mm
3)
Urine day 1 average SW
Daily nitrous oxide flux and soil water
0
40
80
120
160
200
240
Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10
Flu
x (g
N2O
-N/h
a/d
)
-
0.10
0.20
0.30
0.40
0.50
0.60
So
il w
ater
(m
m3/
mm
3)
Urine day 1 Urine day 1 + DCD day 1 average SW
Daily nitrous oxide flux and soil water
0
40
80
120
160
200
240
Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10
Flu
x (g
N2O
-N/h
a/d
)
-
0.10
0.20
0.30
0.40
0.50
0.60
So
il w
ater
(m
m3/
mm
3)
Urine day 28 Urine day 28 + DCD day 1 average SW
Daily nitrous oxide flux and soil water
0
40
80
120
160
200
240
Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10
Flu
x (g
N2O
-N/h
a/d
)
-
0.10
0.20
0.30
0.40
0.50
0.60
So
il w
ater
(m
m3/
mm
3)
Urine day 1 Urine day 1 + DCD day 1 Urine day 28 Urine day 28 + DCD day 1 average SW
Summary of nitrous oxide emissions
-4
-3
-2
-1
0
1
2
3
4
Day 1-30 Day 31-60 Day 61-90 Day 91-120 Day 121-150 Total (150)
Flu
x (k
g N
2O
-N/h
a/p
eri
od
)
0
1
2
3
4
5
6
7
8
Flu
x (k
g N
2O
-N/h
a/p
eri
od
)
Urine 28 days after start DCD at start, Urine 28 days after start Urine at start Urine and DCD at start
August 2009 start
April 2010 start
Effects of treatment on DM yields
Urine Urine + DCD(day 1 – day 1)
DCD + Urine(day 1 – day 28)
Late winter 4 of 5 3 of 5 1 of 5
(2009) (30-160%) (10-15%) (10%)
Autumn 5 of 6 3 of 6 3 of 6
(2010) (30-120%) (10-20%) (10-15%)
Summary
• DCD application reduced emissions by 35 and 45% both when applied immediately after urine applied and when applied one month prior to urine application
• Impact of DCD on emissions likely to be at least 90 days when applied in late winter or autumn • Impact of DCD on DM production at whole of paddock scale likely to be minimal
Acknowledgements