Defining the pathway for remediating mining land for productive, profitable, and sustainable beef production

Summary

This project worked to define a pathway for remediating mining land for productive, profitable, and sustainable beef production in the Bowen Basin. Coal mining companies own or manage up to 760K hectares in this region, comprising 557K hectares of granted mining lease (ML) and an additional 202,931 hectares that sit adjacent to ML areas. Though 90% of this area historically supported grazing, mining operations exclude commercial livestock production from most of the ML land, reducing the livestock carrying capacity within the Bowen Basin by more than 100K Adult Equivalents (AE).

Despite a common expectation grazing land will be rehabilitated for this same end use, current topsoil deficits of 30-50% relative to requirements can necessitate the use of sodic and dispersive spoil materials that may not accommodate conventional grazing practices on inevitably sloped reconstructed landforms.

The mining industry requires a scalable system for achieving viable and productive livestock production on these sloped landforms if it is to create as much grazing post-mining land use (PMLU) as possible. This project has undertaken to define a silvopastoral model for achieving this outcome. The project anticipates the research and development requirements for overcoming or minimising this implementation gap. It concluded by considering the use of new and emerging digital technologies to manage the model’s implementation.

Objectives

The objectives of the project were to:

1. Define the opportunity the mine closure process affords the beef industry in the Bowen Basin.
2. Identify and describe an inventory of practices used to remediate land in this region.
3. Describe the “implementation gap” for implementing a scalable beef production model as a rehabilitation service for mining land.
4. Assess opportunities for overcoming this implementation gap using digital technologies.
5. Deliver a research plan to secure the information, technology, and management practices required for overcoming or minimising this implementation gap.

Key findings

This project found that 557,696 hectares of land in the Bowen Basin is held under mining lease, representing an opportunity cost of nearly $60.8 million/year to the livestock industry.

This project identified three current challenges for rehabilitating this land for productive grazing. Firstly, the mining industry lacks specific design principles for engineering functional grazing PMLU landforms. Secondly, the industry does not yet have scientifically verified and livestock industry supported grazing PMLU completion criteria.

Thirdly, a 30-50% topsoil deficit relative to requirements might make it necessary to use sodic and dispersive spoil materials to cover sloped landforms, challenging the establishment and management of ground cover on erosive slopes, increasing the difficulty of achieving sustainable grazing PMLU.

This project developed a model for achieving completion criteria for viable and productive grazing PMLU land and remediating undisturbed historically degraded grazing land.

Benefits to industry

The project’s outcomes benefit the livestock industry by clarifying an opportunity to develop a digitally enabled scalable silvopastoral model that (a) facilitates the rehabilitation of as much land for grazing PMLU as possible by supporting the achievement of completion criteria for viable and productive livestock on sloped land and (b) services carbon and biodiversity objectives for 202,931 hectares of undisturbed grazing land owned or managed by mining companies adjacent to ML areas, and undisturbed ML land as this becomes available for livestock production.

The validation of the proposed digitally enabled silvopastoral model is intended to provide a business opportunity for graziers to gain financially from the mine closure process and produce an educational model for certifying competency for model implementation. The model will also provide livestock producers with confidence to acquire mining land that contains rehabilitated sloped landforms.

Future research

This project recommends the development and validation of a scalable digitally enabled silvopastoral model for delivering environmental services. Research required for delivering this outcome include:

1. Collaborate with the coal mining industry to define mutually acceptable and scientifically verified rehabilitation completion criteria for viable grazing PMLU.
2. Development of design principles that guide the creation of fit-for-purpose grazing PMLU landforms in the Bowen Basin.
3. Development of a grazing management system for achieving viable grazing PMLU completion criteria on sloped landforms.
4. Evaluate commercially relevant tree species and ideal silvopasture architecture for rehabilitated landforms.
5. Configure a scalable silvopastoral model for achieving viable and productive grazing PMLU completion criteria.
6. Develop a digital monitoring and livestock management platform for model implementation on rehabilitated landforms.
7. Conduct a long-term pilot scale evaluation of a digitally enabled and adaptive silvopastoral model on a landform created fit-for-purpose for grazing PMLU.
8. Develop an educational program for certifying competency for model implementation.