Download Greenhouse gas emissions and dairy farms

Greenhouse gas emissions and dairy farms
Zita Ritchie
Dairy Extension Officer DPI Victoria Warrnambool
0
Overview
1. What are greenhouse gases (GHGs)?
2. Source of agricultural greenhouse gas
emissions
3. Greenhouse gas accounting tools- DGAS
4. How to reduce emissions?
5. Wrap up – so what?
Bodalla annual rainfall
Annual rainfall 5 year rolling average
Autumn rainfall 5 year rolling average
What are greenhouse gases?
Greenhouse gases are present in the earth’s
atmosphere which absorb and re-emit
radiation
What are considered to be ‘greenhouse gases’
a)CO2 – carbon dioxide
b)CH4 - methane
c) N2O – nitrous oxide
d)a) and b)
e)All of the above
Physical changes – the
atmosphere
Outer Stratosphere is cooling
Troposphere is warming
(under greenhouse blanket)
How are our climate
drivers responding in a
ENSO
IOD
STR
warmer world?
•ENSO – Pacific Ocean
moisture source
•IOD – Indian Ocean
moisture source
•SAM – the fronts….
•STR – the highs…..
SAM
Blocking
highs
greater
influence
in your
region in
autumn
Have you seen how
ridgy influences high
pressure systems?
Risbey et al
2009
3 Ps of Climate Change
Climate Change
Impacts
Physical
Policy/Political
Peripheral
Agricultural Enterprises
• Temperature
• CO2, Rainfall
• Carbon Tax
• CFI
• Carbon footprint labeling
• Consumer demands
• Carbon trading
Political context
Sectoral Greenhouse Gas Emissions Australia
AGO 2007
Where do most agricultural emissions
come from?
Nitrous
oxide
Field Burning of
Agricultural
Residues
1%
Prescribed
Enteric Methane
– 11% of National emissions
Burning of
Savannas
13%
Agricultural
Soils
17%
Nitrous Oxide from soils
Enteric
Fermentation
65%
– 2.5% of National emissions
Rice Cultivation
0%
Manure
Management
4%
Methane
DCC 2010
Emissions
The need for a single currency – CO2e
•1 unit of CO2 = 1 unit of CO2e
•1 unit of methane ≡ 25 units of CO2e
•1 unit of nitrous oxide ≡ 298 units of CO2e
Powerful global warming
potential
methane = 25 x CO2
nitrous oxide = 298 x
CO2
So what are the current political
responses?
1. Price on carbon – to achieve reduction
from biggest emitters
Agricultural emissions exempt at this point in time
2. Carbon Farming Initiative (CFI) –
voluntary offset market for agriculture
(Opportunities may arise for agriculture?)
3 Ps of Climate Change
Climate Change
Impacts
Physical
Policy/Political
Peripheral
Agricultural Enterprises
• Temperature
• CO2, Rainfall
• Carbon Tax
• CFI
• Carbon footprint labeling
• Consumer demands
• Carbon trading
Larger drivers of change
Lead by consumers or to be stipulated by
large supply chains?
Carbon footprint labelling (supermarkets eg
Tesco UK, Japan Govt, etc)
Will carbon become differentiator or
business as usual?
DPI Agribusiness
Life cycle analysis of skim milk
powder shipped to Japan
What is a life cycle analysis?: a
way to measure emissions
along whole supply chain (to
get a carbon footprint of a
% breakdown of GHG emissions along the chain - Farm to port
product)
LCA
1 t skim milk powder exported to
Japan
Typical dairy farm emissions
N2O - Dung,
Urine & Spread
10%
Nitrous oxide
sources
74% methane from
cows
N2O - Indirect
11%
N2O - N
Fertiliser
4%
CH4 - Effluent
ponds
1%
CH4 - Enteric
74%
Driven by how
intensive /
extensive
management
system is
N2O - Effluent
ponds
0%
3 - 7 t CO2e / cow
R. Eckard, 2009
Methane emissions from cows
Produced by methanogens in rumen
Most breathed or belched
Represent a significant loss of energy
Equivalent grazing Potential km driven
days of energy lost
in 6-cylinder car
per animal
Animal Class
Methane (kg/year)
Mature ewe
10 to 13
41 to 53
90 to 116
Beef steer
50 to 90
32 to 57
450 to 800
Dairy cow
90 to 146
24 to 38
800 to 1350
What emissions does your farm
produce?
“You can’t manage what you don’t
know”
Tools available
Greenhouse in agriculture – dairy, beef,
sheep, grains
Dairy Greenhouse Abatement Strategy
(DGAS)
FarmGAS (sheep and beef)
Farm Inputs page
So why calculate emissions?
Identify and reduce production inefficiencies /
biggest emission sources
Marketing tool
Preparation for GHG labeling
Prepare for emissions policies?
So what? How can we reduce these?
Different depending on where the farm is
at / capacity to respond
Win-win options consistent with best
practice
– Improve production efficiency
– Reduce methane and nitrous oxide
Integrate GHG best prac into existing
adoption pathways, not as a separate
entity!
Enteric Methane Mitigation Timeline
Mitigation %
“Silver bullet”
45
40
35
30
25
20
15
10
5
0
Biological control
Vaccination
Dietary
Supplements
Rumen manipulation
Breeding
BMPs
Herd Management
Low
Immediate
High
Medium
Likely
Impact
Timeline
Confidence
High
Longer Term
Low
Eckard et al. 2009
Methane Mitigation Options
Short term
– Reducing unproductive animal numbers (10 – 15%)
• Extended lactation
• Reproduction, fertility & health
– Feed quality (5-15%)
• Pasture improvement
• C3 pastures, legumes
Eckard, Grainger & de Klein 2010
Methane Mitigation Options
Short term
– Dietary supplements
• Grain (5 - 20%)
• Dietary oils eg cotton seed oil (5 - 25%)
– 1% fat = 3.6% decrease CH4 /kg DM
• Tannins eg black wattle (13 - 29%)
Eckard, Grainger & de Klein 2010; Moate, Williams, Eckard et al. 2010
Methane Mitigation Options
(cont)
Medium Term
– Animal Breeding (10 – 20%)
• Feed conversion efficiency
• Reduced methanogenesis
Longer-term
– Rumen manipulation/ biological control
• Vaccination
• Competitive or predatory microbes
Nitrous Oxide (N2O)
N fertiliser
N2O
Legumes
Excreta
NH4
NO3
N2
Denitrification
Mineralisation
Excess and inefficient use of nitrogen leads to release of N2O
– Ruminants excrete 75 to 95% of N intake
• >60% lost
Nitrous Oxide Mitigation Timeline
“Silver bullet”
Biological control
25
Animal
Breeding
Mitigation %
20
15
Nitrification
Inhibitors
10
BMPs
Diet
5
Soil Microbial
Manipulation
Plant
Breeding
Secondary plant
compounds
Herd Management
0
Low
Immediate
High
Likely
Impact
Medium
Timeline
Confidence
High
Longer Term
Low
De Klein & Eckard 2008
Abatement Options – Short term
Nitrogen Fertiliser
– Rate, source, timing, placement
– Urease inhibitors eg green urea
Water management
– Drainage, irrigation
Soil Management
– Compaction, tillage
Animal Management
– Stocking density, diet, effluent
Abatement Strategies
GHG emissions
Enteric Methane
Herd based strategies
10-20% potential
Nitrous oxide
Herd based strategies
10-50% potential reduction
in urinary nitrogen
‘There are so many different business
scenariosExtended
for lactations
each individual farm’
Reduced herd size
Higher FCE
Extended longevity
in the herd
Research undertaken in
Australia and New
Zealand has identified an
array of potential
abatement strategies for
dairy farm systems.
Eckard et al.
Feed based strategies
10-20% potential
Feeding fats & oils
Feeding condensed tannins
Feeding ionophores
Maximise diet digestibility
Condensed tannins
Nitrification inhibitors in urine
Higher FCE
Balance crude protein in the
diet
Soil based strategies
10-20% potential
Nitrification inhibitors
Stand-off pads during winter
Improved drainage
Improved irrigation management
Fertiliser managementrate/ timing/ formulation
Case study example – DemoDAIRY
•
•
•
•
700mm rainfall
148 ha milking area
312 milkers, dries ran off farm
12 ha trees
Currently Utilising Herd, Feed,
Fertiliser BMP’s
TOTAL FARM EMISSIONS
12.4 t CO2-eq/ tonne ms
Baseline Contributors to Total
Em issions
19%
29%
6%
46%
P re-farm
On-farm CO2
On-farm CH4
On-farm N2O
After abatement: dietary oils, tannins,
nitrification inhibitors.
12.4 to 10.1 t CO2-eq/ t ms
(Around 17% reduction )
Have many dairy farmers
calculated their emissions or are
doing anything?
Farmers Taking Action
Trevor Thomas
Dairy Farmer –Longwarry (Gippsland)
150 Ha property | 200 milking cows | 1.5 ha of trees planted | 130 ha dryland pasture
KEY POINTS
•Production improvement options are linked to greenhouse gas emissions reduction.
•Consider emissions reduction options that lead to productivity gains or have cost benefits.
“By looking at these strategies I
hope to contribute to a
reduction in greenhouse gases,
which will hopefully be a win for
the environment and a win for
me in terms of cost and
production at the same time”.
Key sources of emissions on Trevor’s farm were:
• methane (CH4) 54%
• nitrous oxide (N2O) 22%
•Embedded emissions (or emissions from pre-farm processes) 16%
•Energy from fuel and electricity contributed only 8% of total emissions
Abatement options Trevor would consider
1. Extended lactation
2. Dietary oils
3. Nitrification inhibitors
“we definitely have to change – emissions
reduction and production improvement
options on farm are all linked together”.”
Farmers Taking Action
Russel and Linda White
Dairy Farmers – Warrnambool
130 Ha property | 200 head | Solar installed in 2005
Key Points
• A solar hot water system can reduce your dairy power costs
• Find the solar hot water system that best suits your needs.
Motivation:
To reduce cost of electricity bill and to reduce environmental impact
5 key action areas
(Each of these is has ready gains…)
Take home messages:
Emissions on farm can be measured right
now
Abatement options do exist
– Focus on improving production efficiency
– Reduce GHG
• At least/unit product
Focus on the win-win options, not the
“what if’s”
Toolkits available
www.dairyaustralia.com.au
For a free electronic subscription
email [email protected]
More information…
http://www.dpi.vic.gov.au/climaterisk
Zita Ritchie
[email protected]