Progress with New Zealand technologies: nitrous oxide Cecile de Klein and Hong Di AgResearch Lincoln University NZ Agricultural Greenhouse Gas Mitigation Conference 28 March 2017
Progress with New Zealand technologies: nitrous oxide
Cecile de Klein and Hong DiAgResearch Lincoln University
NZ Agricultural Greenhouse Gas Mitigation Conference 28 March 2017
Sources of N2O in NZ agriculture
96 %
New Zealand National Inventory Report 2016
Excreta from grazing animals
Nitrogen fertiliser
dung
urine
Excreta N is recycled N –originates from clover fixation or fertiliser applications
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Nitrate Ammonium Urea
Nitrous oxide
leaching
Nitrification inhibitors
0
5
10
15
20
25
< 20 20-40 40-60 60-80 >80
Num
ber o
f stu
dies
% Reduction in N2O loss from urine patch
Nitrification inhibitors reduce N2O emissions from urine patches
~ 50 NZ values
Average reduction: 50%
Di and Cameron (2016); de Klein et al (2011)NZ Agricultural Greenhouse Gas Mitigation Conference
11 May 2017 |
Plant screening shows difference in N2O emissions from urine patches
11 May 2017 | 5total N2O emission (kg N2O-N ha-1)
0 1 2 3 4 5 6
Italian ryegrass cv MoataPerennial ryegrass cv Rely
CocksfootPerennial ryegrass cv Halo
Perennial ryegrass cv Aber MagicPlantain
Perennial ryegrass cv RohanPasture mix
BrowntopYorkshire fogForage rape
ChicoryPrairie grass
Italian ryegrass cv TamaWhite clover cv BountyWhite clover cv Weka
Upland bromeBare soil
Bowatte et al. 2017
Same type and amount of urine applied to all plots
Natural nitrification inhibition?
Nitrate Ammonium Urea
Nitrous oxide
leaching
N uptake
75-90%
N in diet
Reduced urine N
Other plant effects on N2O
Reducing N excretion?
Increasing N uptake by plants?
Enhancing natural nitrification inhibition?
Can we use plant species to reduce N2O emissions by:
Nitrate Ammonium Urea
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Forages for reduced N leaching• Aim: to reduce nitrate leaching losses by 20 %• DairyNZ-led with range of partners• The principal funder is the Ministry of Business, Innovation and
Employment; all partners co-fund the programme
Pastoral 21• Aim: to provide solutions for lifting production and reduced nutrient loss• AgResearch-led with range of partners• Funded through a collaborative venture between DairyNZ, Fonterra, Dairy
Companies Association of New Zealand, Beef + Lamb New Zealand and the Ministry of Business, Innovation and employment
Partner programmes
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Reduce N excretion?
Increase N uptake by plants?
Enhance natural nitrification inhibition?
Key findings from the N2O programme
Nitrate Ammonium Urea
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Reduced N excretion – diverse pasture
Di et al.Standard pasture Diverse pasture
Standard pastureTypical loading rate: 700N
Diverse pasture Typical loading rate: 500N
0
1
2
3
4
5
6
7
8
9
10
Tetraploid_Control Tetraploid_U500 Tetraploid_U700 Diverse_Control Diverse_U500 Diverse_U700
Tota
l N2O
-N e
mis
sion
s, k
g N
2O-N
/ha
0.69 % 1.03 %0.84 %1.12 %Emission factors:
Control Urine 500N Urine 700N Control Urine 500N Urine 700NDi et al., 2016
February urine application April urine application June urine application
EF3 (%)
0.0
0.2
0.4
0.6
0.8
Ryegrass Lucerne Plantain
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8 Plant scorching damage
June 2015
Increased N uptake?– lucerne, plantain
11
Luo et al.
620-700 kg N/ha urine from cows on standard perennial ryegrass/white clover pasture
N uptake (kg N/ha/yr)317 714348
N2O
em
itted
(% o
f N a
pplie
d)
February 2016 April 2016 June 2016
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Reduce N excretion?
Increase N uptake by plants?
Enhance natural nitrification inhibition?
Can we use plant species or feeding options to:
Nitrate Ammonium Urea
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Enhancing natural nitrification inhibition – urine composition or root exudates
Balvert et al & Gardiner et al.
Compounds in plants that can affect N2O?- glucosinolate (Brassicas)?- aucubin (Plantain)?
11 May 2017 | 14
Some glucosinolatehydrolysis compounds reduced N2O emissions in lab screening study
Urea on
ly
Pheny
lethy
l ITC
2 prop
enyl I
TC
2 prop
enyl N
4 pen
t-1-yl
ITC
4 pen
tene N
All inhib
itors
% o
f app
lied
N e
mitt
ed a
s N
2O-N
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
a
aa
a
aa
b
Balvert et al.
Natural nitrification inhibition? – glucosinolates(Brassicas)
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
Natural nitrification inhibition? – Aucubin(Plantain)
11 May 2017 | 15
Field trial (Canterbury): Plantain plant extract or Aucubin added to urine
Aucubin reduced N2O emission factor
Mode of action unclear
0.0 %
1.0 %
2.0 %
3.0 %
4.0 %
Urine Plant Extract Aucubin
Emission Factor
a ab b
Gardiner et al.NZ Agricultural Greenhouse Gas Mitigation Conference
11 May 2017 |
Kale Urine 300
Treatments
c
EF3=1.1
Natural nitrification inhibition? – fodder beet
11 May 2017 | 16
Di et al.
b0
1
2
3
4
5
6
7
8
9
10
Fodder beet Urine300
Tota
l N
2O e
mis
sio
(kg
N 2O
-N h
a-1 )
b
EF3=0.85
a
Di et al., 2016
Emissions from fodder beet were lower than from kale –plant effect or urine composition effect?
Fodder beet urine Kale urine
Nitrate Ammonium Urea
Nitrous oxide
leaching
Nitrification inhibitors Urease inhibitors
-2000
0
2000
4000
6000
8000
10000
0 5 10 15 20 25
Urine patches measured at 7pm
Deposited 10:40am Deposited 2:40pm
Deposited 6:40pm
timeData
Spikey® - NZ developed ground-based sensor system detects and treats fresh urine patches
Effect of target-application of inhibitors
0
20
40
60
80
100
Urine + Nitrificationinhibitor
+ UreaseinhibitorEm
issi
ons r
elat
ive
to u
rine
(%)
Ammonia volatilisation
0
20
40
60
80
100
Urine + Nitrificationinhibitor
+ Ureaseinhibitor
+ bothEmis
sion
s rel
ativ
e to
urin
e (%
)
Nitrous oxide
Hoogendoorn et al.
Early results promising
Plants can affect N2O emissions:• reduced N excretion (diverse pastures)• increased N uptake? • natural nitrification inhibition (plantain,
fodder beet?) – root exudes and/or urine
Next stage:• better understanding mechanisms• examine delivery pathways• assess impacts at systems level
In summary
Nitrate Ammonium Urea
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |
FundingNew Zealand Greenhouse Gas Research CentreMinistry for Primary Industries
Partner programmesForage for Reduced N leaching Pastoral 21
Collaborators and contributorsAgResearch: Jiafa Luo, Sheree Balvert, Saman Bowatte, Tony van der
Weerden, Stewart Ledgard, Brendon WeltenLincoln University: Keith Cameron, Andriy Podolyan, Tim Clough,
Camilla Gardiner, Grant Edwards, Rachael BryantDairyNZ: Ina Pinxterhuis, David Chapman, Dawn DalleyLandcare Research: Surinder Saggar, Coby HoogendoornPastoral Robotics: Geoff Bates, Bert Quin
Acknowledgements
NZ Agricultural Greenhouse Gas Mitigation Conference 11 May 2017 |