IMAGE: JULIE REARDON
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Australian irrigated lint yields are now the highest in
the world, being about three times the world average.
Australian cotton growers produce more crop per
drop than any other cotton producing country
Each gigalitre of water used for cotton production
results in 1.3 direct jobs and generates $500,000 in
gross value agricultural production (source: Stubbs
Report, 2012)
In 2014, 70 percent of cotton farmers use soil
moisture probes, up from 40 percent in 2006 (highest
of all agriculture industries in Australia)
96 percent of irrigators have improved their furrow
irrigation system or changed to an alternate
irrigation system
WATER USE
EFFICIENCY IN THE
COTTON INDUSTRY
Australian irrigated lint yields are now the highest of any major
cotton producing country in the world, being about three times
the world average. This means Australia cotton growers produce
more crop per drop than any other cotton producing country
The Australian cotton industry has achieved a 40% increase
in water productivity over the last decade. (source: Australian
Grown Cotton Sustainability Report 2014)
The CSIRO breeds appropriate cotton varieties for Australian
and regional conditions. Each grower selects the best and most
efficient variety for their region and farm
Cotton is an efficient plant, with the latest industry data showing
approximately 70% of all water is used by the crop. This indicates
that there is now less on-farm water losses and more of the water
is used by the crop
Most cotton growers have what are termed “general, or low
security” water licences, which means they only get to access
their share of the water once the needs of towns, stock and
domestic use and the environment are met
Cotton is only planted when sufficient water is made available
from rivers and groundwater sources through government
regulated water licensing schemes. When there’s no water,
there’s no cotton
In their ‘natural’ state, the rivers located in the southern half of
Australia experience more variable flows than virtually any other
rivers in the world. Between 1885 and 1960, history shows the
Darling River stopped flowing at Menindee on 48 occasions –
well before irrigation existed on the river or its tributaries
IMAGE: JAMIE CONDON
WATER USE
EFFICIENCY IN THE
COTTON INDUSTRY
Cotton is mostly grown in the 400-800mm summer rainfall zone,
which means cotton crops can receive significant amounts of
their water needs from rain during the growing season. In 201112 about 20% of the cotton crop was rain-grown, the rest irrigated
Australia’s cotton growers have improved water use efficiency
by 3-4% per year since 2003. (source: Third Australian Cotton
Industry Environmental Assessment, September 2012)
Australian cotton growers have almost doubled their irrigation
water use index from 1.1 bales/megalitre in 2000-01 to 1.9 bales/
megalitre in 2009-10
Cotton’s average irrigation requirement is 7.8 megalitres per
hectare. This compares to rice (12.6ML/ha), fruit and nut trees
(5.6 ML/ha) and cut flowers and turf (4.9 ML/ha)Pasture for
grazing accounted for the greatest amount of irrigated land
(538,000 hectares) in Australia in 2010–11, with the volume of
irrigation water applied representing 27% of the national total.
(source: ABS Water Use on Australian Farms 2010-11)
In 2013-14, the largest area of irrigated land in Australia was
pasture and cereal crops used for grazing or fed off, which
accounted for 714,503.2 hectares, or 30% of the total area
irrigated (source: ABS Water Use on Australian Farms 2010-11)
The largest volume of irrigation water was applied to cotton,
which used 2,851 gigalitres, or 26% of the national irrigation
total for the year (11,060 gigalitres) (source: ABS Water Use on
Australian Farms 2010-11). 566,000 hectares were planted to
cotton in 2010-11
Cotton is the lifeblood of many regional communities, employing
10,000 Australians in Queensland and NSW in a
non-drought year
Each gigalitre of water used for cotton production results in 1.3
direct jobs and generates $500,000 in gross value agricultural
production. (source: Stubbs Report, 2012)
Irrigation water for agriculture is used on the highest value crops.
Farmers choose to “spend” their water entitlements on the crops
that deliver the best return per unit of water, in many areas that
crop is cotton
Once planted, Australian cotton farmers are
smart about the way they manage water
resources. The Australian Grown Cotton
Sustainability Report 2014 showed that cotton
growers are using a range of techniques to
constantly improve water use efficiency:
70 percent of farmers use soil moisture probes, up from 40
percent in 2006 (highest of all agriculture industries in Australia)
96 percent of irrigators have improved their furrow irrigation
system or changed to an alternate irrigation system
49 percent of irrigators had made changes to the flow or size of
their siphons
35 percent have redesigned fields. For example, growers use
laser-levelling to ensure uniform, well drained fields using GPS
guidance equipment and position storage dams closer to cotton
fields to reduce evaporation losses
Other practices include irrigating to deficits, using drip and
overhead sprinkler systems, better accounting of soil variations,
changed bed shapes, using irrigation scheduling probes, furrow
irrigation system optimisation evaluations, pump optimisation and
reducing distribution losses
Additional water use efficiency driving
practices include:
Before planting their crop, cotton growers use sophisticated
weather forecasting software to predict how much crop can be
sustained before planting. Zero and minimum till farming is also
used to help retain soil moisture
Growers use information and technology (including soil moisture
probes, satellites and drones) so they water only when and how
much is needed
Irrigation channels that pump water to the fields are lined to
reduce loss through seepage
Adhering to the Australian cotton industry’s environmental
management program – myBMP. myBMP includes a water
management module covering water quality, efficiency of storage
and distribution for both dryland and irrigated farming practices to
improve farming practices and carefully manage our
natural resources
IMAGE: DONNA HALL
WATER USE
EFFICIENCY IN THE
COTTON INDUSTRY
These systems can achieve labour savings and with some soil
types, water savings (about 30 percent), but have significantly
higher energy costs associated with water pumping and
machine operation
Mobile electromagnetic meters are used for easy and rapid
assessment of soils for their suitability for irrigation
Tail water recycling systems are implemented so that water
is reused
Covering storages to minimise evaporation
Reducing evaporation by shortening row lengths
Avoiding unnecessary water storage on farm by only purchasing
water as it is needed and not putting water directly into dry
storages which soak up water
Growers are and lining storages and channels with clay or
non-porous materials to avoid seepage. Thermal imaging and
electromagnetic surveys can be used to identify “leaky” dams,
pipes and channels so they can be repaired
Mulching and stubble retention helps to retain soil moisture,
reducing the need for irrigations
Permanent wheel beds to reduce soil compaction and increase
water infiltration
Implementing software packages such as Water Track
(www.watertrack.com.au)
© Cotton Australia 2016. This material is licensed under a
Creative Commons Attribution-Non Commercial 4.0
International License (CC BY CC BY-NC 4)
IMAGE: GEORGIE CARRIGAN
Farmers are changing to alternative irrigation systems such as
centre pivots and lateral move systems and it is expected there
will be an increasing number of these machines in the future