This project was to develop insight into the future of rainfed cotton systems by developing an understanding of soil carbon and water use efficiency across a number of current rotation options.

The project included:

• a review of work on optimal farming systems and the influence of long-term rotations including cover cropping and the introduction of pulses, cereals and fallow on water use efficiency and profitability
• consultation across the rainfed cropping industry to identify existing innovative tactics currently being used by growers
• the establishment of two legacy sites for demonstration trials to compare current rotations in commercial enterprises with the benefits of carbon accumulation on sustainability and profitability
• Farm walks/field days to support information delivery
• economic analysis, and
• the development of a suite of case studies encompassing innovative farming tactics to deal with climate variability. 

There is an appetite for understanding more about soil organic carbon and the benefits of managing a rainfed cropping system to accumulate soil carbon.

Rainfed cotton growers still indicate that they don’t understand how soil organic carbon fits into their farming system and are unsure of how to make evidence based, on-farm decisions specifically around soil organic carbon. Likewise, despite the uptake of technology to monitor soil moisture growers and their advisors are unsure how to use the data to make on-farm decisions. This project was to look at the interaction of soil organic carbon and water use efficiency so this constraint to adoption needs to be addressed.

The rainfed cotton industry could benefit from further investigation in to:

• Economic and sustainability analysis on the use of enhanced efficiency fertilisers in crop rotations to reduce emissions, alongside organic products such as manure pellets.
• Whole farm carbon footprint analysis and measuring biodiversity scores across various dryland regions where local vegetation species can be identified to improve the accuracy of sequestered carbon may be useful to build awareness of the value and stewardship of non-cropped areas.
• Conducting a review of emerging biodiversity score ‘tools’ available and their value in the marketplace is an emerging area of consumer and brand influence.
• Given the low relative carbon/water footprints of dryland cotton - owing to modest nitrogen use and on-farm vegetation, exploratory economic analysis on dryland cotton branding premiums in the marketplace has commercial potential.
• Consumer/brand market research, EU market access, accreditation design parameters, traceability frameworks in a prospective unique supply chain benefit cost study may also be valuable for dryland cotton growers.
• Continued research at the two legacy sites established to consolidate the work already completed over a longer timeframe within varying climatic conditions.
• Develop standardized, simple sustainability metrics
• Investigate standardized testing protocol for dryland cotton systems taking into account carbon fluctuations and rigor around testing
• Review the CRDC data agreement to determine if data from previous projects can be shared for analysis
• Managing systems for soil carbon accumulation in sodic, cracking soils
• Investigate what cover crops have been trialled in horticulture that may be suitable for dryland cotton systems
• Investigate breeding specific cover crops with high biomass, fast growing and persistent traits for increasing soil carbon in dryland cotton systems
• Investigate aggregating soil test and rotation data together from 2019 for at least one site
• Investigate the marketing of rain grown carbon neutral cotton differently to irrigated cotton.

This project, while a good start, requires further investment to realise the full value of the work already completed.

As technology improves and research learnings are ground truth in commercial systems the development of simple to use tools will be critical to facilitate integration of these profitability and sustainability concepts into current rainfed cotton cropping systems.