Benefits of adopting seed-based technologies for rehabilitation in the mining sector: a Pilbara perspective

Abstract

The use of native plant seeds is fundamental to large-scale rehabilitation and the re-establishment of self-sustaining ecosystems after high-impact mining activity has ceased. However, many of the biological attributes of seeds are often overlooked in large-scale rehabilitation programs. Multi-disciplinary, long-term research collaborations are required to improve seed-based mine rehabilitation. In this paper, we review the steps that BHP Western Australia Iron Ore (WAIO), a large iron ore mining company that operates in the Pilbara bioregion of north-west Western Australia, has taken over the past 9 years to ensure continuous improvement in rehabilitation procedures. We introduce the mining activities that WAIO undertake in the Pilbara, and emphasise specific examples of how research findings have led to incremental improvements in the seed management cycle, growth media management and mine rehabilitation practices. Specifically, we outline how the implementation of structured seed collection and storage programs has created the capacity to maintain high-quality seed stocks sufficient for 3–5 years of future rehabilitation. Research has documented the prevalence of seed dormancy in the flora (>70% of 105 species examined produce dormant seeds), with physical and physiological classes of dormancy most commonly encountered. We discuss the development of seed-treatments such as optimised wet-heat and dry after-ripening that have increased the germination capacity of many previously dormant seed batches. In addition, we highlight how seed enhancement technologies, such as hydro-priming with smoke-derived germination stimulants and polymer seed coating, and a greater understanding of the biological and physical limitations present in the growing environment, have vastly improved seedling emergence performance under field conditions for key framework Triodia species. Ongoing industry support (e.g. construction of a purpose-built rain manipulation shelter) has ensured research in the Pilbara will continue to unpack and resolve the complex challenges associated with seed regeneration of biodiverse native plant communities after mining.

A research agenda for seed‐trait functional ecology

“…Large‐scale restoration often relies on seed, and therefore on knowledge of seed production, dormancy and germination characteristics (Merritt & Dixon, ). These traits may be key for determining the suitability of species for restoration (Perring et al ., ; Ladouceur et al ., ), for optimizing pre‐treatments to enhance performance such as emergence (Commander et al ., ; Erickson et al ., ) and drought tolerance (Lewandrowski et al ., ), for understanding when and where seeds may germinate (Commander et al ., ), or for promoting germination by applying specific cues (Tieu, ). The interaction between seed traits and abiotic factors such as soil physicochemical properties may influence seedling emergence patterns and consequently seedling community composition in restored areas (Merino‐Martín et al ., 2017a).…”

Direct seeding and outplantings in drylands of Argentinean Patagonia: estimated costs, and prospects for large‐scale restoration and rehabilitation

“…In the same arid ecosystem in Western Australia, more encouraging results were reported for the putative framework species, the perennial grass known as soft spinifex, Triodia pungens . In this case, seedling survivals from direct seeding was 5% without soil amendments for seeding beds but reached 40% with the application of hydro‐priming in the form of sophisticated smoke‐derived germination stimulants and polymer seed coating (Erickson et al ).…”

Seeds at the forefront: synthesis of the inaugural National Seed Science Forum and future directions in Australian seed science

“…Protection of populations of rare plant species or communities against decline due to various threatening processes such as mining or the fragmentation caused by past land use is paramount. Using seeds to achieve conservation and restoration aims is increasingly common and requires a detailed understanding of many aspects of seed biology, as evidenced by the papers of Turner et al (2017), Erickson et al (2017), and Vening et al (2017) in this issue.…”

“…Multiple species, rare and common, may be impacted by mining. In their paper, Benefits of adopting seed-based technologies for rehabilitation in the mining sector: a Pilbara perspective, Erickson et al (2017) discuss a long-term partnership between ecological scientists and environmental staff in the mining sector. The authors detail how scientific findings have informed management practices for mine site rehabilitation.…”

“…Madsen et al 2016;Erickson et al 2017). The challenge remains, for many species, to develop seed treatments that are reliable, repeatable, and applicable to large-volumes of diverse seed collections required for landscape scale restoration (Merritt and Dixon 2011).…”