SA Graan January 2019

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January 2019
INPUTS ASSUMPTIONS
Yield Increase with 10%
Fuel Decrease with 50%
Fertiliser Decrease with 50%
Lime No change
Fungicides Decrease with 50%
Herbicides Decrease with 50%
Insecticides Decrease with 60%
Burning of crop residues No burning
% of the above ground residue removed 30% removed
TABLE 1: ASSUMPTIONS FOR INPUTS FOR FUTURE CA SYSTEMS.
REGION
FARMING SYSTEM
CONVENTIONAL CA FUTURE CA
Darling/Hopefield Wheat
Wheat Wheat
Medics Medics
Lupins Canola
Northern Swartland Wheat
Wheat Wheat
Medics Medics
Middle Swartland Wheat
Wheat Wheat
Medics Barley
Canola
Southern Swartland Wheat
Wheat Wheat
Medics Medics
Canola Canola
Western Rûens Wheat
Wheat Wheat
Barley Barley
Canola Canola
Southern Rûens Wheat
Wheat Wheat
Barley Barley
Canola Canola
Eastern Rûens Wheat
Wheat Wheat
Barley Barley
Canola Canola
TABLE 2: WINTER GRAIN SUB-REGIONS WITH CORRESPONDING
CROP ROTATIONS AND FARMING SYSTEMS.
REGION TOTAL TONNAGE
CARBON EMIS-
SIONS FOR REGION
(KG CO2e/TON
GRAIN)
Darling/Hopefield 54 507 597,23
Northern Swartland 146 217 534,76
Middle Swartland 276 399 555,90
Southern Swartland 21 896 609,73
Western Rûens 182 449 637,92
Southern Rûens 209 245 485,85
Eastern Rûens 325 585 396,22
Weighted average 513,70
REGION TOTAL TONNAGE
CARBON EMIS-
SIONS FOR REGION
(KG CO2e/TON
GRAIN)
Darling/Hopefield 58 993 339,93
Northern Swartland 157 914 327,68
Middle Swartland 307 043 314,72
Southern Swartland 22 283 400,70
Western Rûens 182 575 418,47
Southern Rûens 207 598 334,52
Eastern Rûens 315 426 276 38
Weighted average 327,83
TABLE 3: CARBON EMISSIONS PER TON GRAIN FOR CURRENT
SCENARIO PER SUB-REGION AND OVERALL.
TABLE 4: CARBON EMISSIONS FOR FUTURE SCENARIO
PER SUB-REGION.
Phase 1 was the start of a longer term
process of using the carbon footprint
methodology and results within the grain
industry as an adaptive management tool
(Figure 1).
Project scope and
methodology
The study only included activities and in-
puts at the farm stage of the grain value
chain. The methodology used to calculate
the carbon emissions per ton grain was the
PAS 2050: 2011 protocol developed by the
British Standards Institute (BSI). Carbon
emissions is only one of a range of impacts
that needs to be taken into account to obtain
a holistic view of the environmental impacts
of a farming system.
Winter grain sub-regions included in this
study are presented in Figure 2. Existing
data (inputs and yields) was collected from
representative production practices in each
region to model the current scenario of car-
bon emissions.
The current scenario consists of a combi-
nation of conventional and conservation
agriculture farming systems (current CA)
currently practiced in these regions. For
the future scenario, an ideal but realistic CA
system (future CA) predicted to be adopted
by most grain producers 20 years into the
future was calculated with corresponding
inputs and yields.
In the Western Cape there is currently no
big difference between conventional farm-
ing and CA. The conventional wheat farm-
ing system does not practise crop rotation
and therefore wheat is planted every year.
In the current CA and future CA systems
crop rotation is practised and the commodi-
ties included in the models per region were
wheat, barley, canola, medics and lupins.
All inputs were specified on a per hectare
basis. The carbon emissions (kg CO 2e/ton)
per farming system were calculated from
the data provided.