Compromised root development constrains the establishment potential of native plants in unamended alkaline post-mining substrates
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Background and aims
Mined materials often require rehabilitation or ecological restoration through revegetation as part of mine closure and relinquishment practices, yet there is a widening gap between the expectations of recovery and what industry achieve. The edaphic conditions of post-mining substrates present a suite of potential limitations to plant growth and may constrain the establishment capability and development of native species.
We assessed seedling emergence, relative growth rate and calculated standardised growth estimates using 10 measured root and shoot parameters for six locally-dominant native species from different families and nutrient-acquisition strategies in a range of representative mining restoration substrates (topsoil, tailings, capped tailings and waste rock), examining their suitability as pioneers for ecological restoration.
The establishment and growth of all six species in post-mining substrates were significantly compromised. Root development was significantly responsive to substrate, with measured root parameters on average 27% lower in capped tailings, 41% lower in waste rock and 67% lower for individuals grown in tailings compared with those grown in topsoil alone. Plant growth was compromised at different life cycle stages (seed germination, seedling establishment, early growth and development) and across a number of different traits, with primary edaphic constraints including high pH (>8.5) and insufficient available N. The highest-performing species on post-mining substrates was an N2-fixing legume, while lowest-performing species included those with ectomycorrhizal associations or no specific nutrient-acquisition strategy.
Edaphic filters may be significant drivers of trajectory and success in rehabilitation and restoration projects at scales ranging from individuals (by limiting establishment or constraining growth and development) to communities (by causing species to assemble in a different manner than the desired reference community). If intractable edaphic parameters constraining plant establishment and early development such as extreme pH and a lack of available nutrients are not ameliorated, the restoration trajectory on post-mining landforms is likely unfavourable. Failure to adequately ameliorate post-mining substrates may represent a major liability for industry in meeting mine-closure requirements.
KeywordsAlkaline substrates Calcicole Calcifuge Ecological restoration Edaphic filters Plant development Plant mineral nutrition Mine tailings Rehabilitation
The authors thank EJ Safe for helpful comments on the manuscript. This research was supported by the Australian Government through the Australian Research Council (ARC) Industrial Transformation Training Centre for Mine Site Restoration (Project Number ICI150100041) and ARC Linkage project LP 019806. The views expressed herein are those of the authors and are not necessarily those of the Australian Government or Australian Research Council.
- Bates D, Mächler M, Bolker B, Walker S (2014) Fitting linear mixed-effects models using lme4. J Stat Softw 67:1–48Google Scholar
- Beard JS (1990) Plant Life of Western Australia. Kangaroo Press, PerthGoogle Scholar
- Brooks ME, Kristensen K, van Benthem KJ, Magnusson A, Berg CW, Nielsen A, Skaug HJ, Machler M, Bolker BM (2017) glmmTMB balances speed and flexibility among packages for zero-inflated generalized linear mixed modeling. R Journal 9:378–400Google Scholar
- Clark RB, Baligar VC (2000) Acidic and alkaline soil constraints on plant mineral nutrition. In: Wilkinson RE (ed) Plant-environment interactions, 2nd edn. CRC Press, Boca Raton, pp 133–177Google Scholar
- Curaqueo G, Schoebitz M, Borie F, Caravaca F, Roldán A (2014) Inoculation with arbuscular mycorrhizal fungi and addition of composted olive-mill waste enhance plant establishment and soil properties in the regeneration of a heavy metal-polluted environment. Environ Sci Pollut Res 21:7403–7412CrossRefGoogle Scholar
- DMIRS (2018) Guidance note – environmental outcomes for mining proposals. Government of Western Australia, Department of Mines, Industry Regulation and Safety. Perth, AustraliaGoogle Scholar
- DMP (2015) Guidelines for preparing mine closure plans. Department of Mines and Petroleum/Environmental Protection Authority, Government of Western Australia, PerthGoogle Scholar
- DMP-EPA (2015) Guidelines for preparing mine closure plans. Government of Western Australia, Department of Mines and Petroleum and environmental protection authority. Perth, AustraliaGoogle Scholar
- EPA (2009a) Karara Iron Ore Project. Report and recommendations of the Environmental Protection Authority, Report 1321. Government of Western Australia. Perth, AustraliaGoogle Scholar
- EPA (2009b) Koolanooka/Blue Hills Direct Shipping Ore Mining Project Shires of Morawa and Perenjori. Report of the Environmental Protection Authority, Report 1328. Government of Western Australia. Perth, AustraliaGoogle Scholar
- Glenn V, Doley D, Unger C, McCaffrey N, McKenna P, Gillespie M, Williams E (2014) Mined land rehabilitation-is there a gap between regulatory guidance and successful relinquishment? AusIMM Bull 3:48–54Google Scholar
- Huang L, Baumgartl T, Mulligan D (2011) Organic matter amendment in copper mine tailings improving primary physical structure, water storage and native grass growth. In: Sanchez, M., Mulligan, D., Wilertz, J. (Eds.), Enviromine 2011, 2nd International Seminar on Environmental Issues in the Mining Industry, Santiago, ChileGoogle Scholar
- Kumaresan D, Cross AT, Moreira-Grez B, Kariman K, Nevill P, Stevens J, Allcock RJN, O’Donnell AG, Dixon KW, Whiteley AS (2017) Microbial functional capacity is preserved within engineered soil formulations used in mine site restoration. Sci Rep 7:564. https://doi.org/10.1038/s41598-017-00650-6 CrossRefPubMedPubMedCentralGoogle Scholar
- Landloch (2006) Soil quality assessment – Karara Iron ore project. Landloch Pty Ltd. PerthGoogle Scholar
- Landwehr G (2016) Mining proposal: Lake Carey project – fortitude gold mine M39/709, M39/710 & M39/1065. Gerrard Consulting Pty Ltd. PerthGoogle Scholar
- Markey AS, Dillon SJ (2008) Flora and vegetation of the banded iron formations of the Yilgarn craton: the central Tallering land system. Cons Sci W Aust 7:121–149Google Scholar
- McDonald T, Gann GD, Jonson K, Dixon KW (2016) International standards for the practice of ecological restoration–including principles and key concepts. Society for Ecological Restoration, WashingtonGoogle Scholar
- Mullan L (2017) Mine closure plan, central Norseman gold mine project. Central Norseman Gold Corporation Pty Ltd, NorsemanGoogle Scholar
- Mulligan DR, Gillespie MJ, Gravina AJ, Currey A (2006) An assessment of the direct revegetation strategy on the tailings storage facility at Kidston gold mine, North Queensland, Australia. In: Fourie A, Tibbett M (eds) Mine Closure, vol 2006. Australian Centre for Geomechanics, Perth, Australia, pp 371–381Google Scholar
- MWH (2016) St Ives gold mine 2016 Mine Closure Plan. MWH Australia Pty Ltd. Perth, AustraliaGoogle Scholar
- Payne AL, van Vreeswyk AME, Leighton KA, Pringle HJ, Hennig P (1998) An inventory and survey of the Sandstone-Yalgoo-Paynes Find area, Western Australia. Technical Bulletin 90. Department of Agriculture and Food. Perth, AustraliaGoogle Scholar
- Roche C, Thygesen K, Baker E (Eds.) (2017) Mine Tailings Storage: Safety Is No Accident. A UNEP Rapid Response Assessment. United Nations Environment Programme and GRID-Arendal, Nairobi and ArendalGoogle Scholar
- Varela RP, Garcia GA, Garcia CM, Ambal AM (2017) Survival and growth of plant species in agroforestry system for progressive rehabilitation of mined nickel sites in Surigao del Norte, Philippines. Ann Stud Sci Hum 2:16–25Google Scholar
- Wu S, Liu Y, Southam G, Robertson L, Chiu TH, Cross AT, Dixon KW, Stevens JC, Zhong H, Chan T, Lu Y, Huang L (2018) Geochemical and mineralogical constraints in magnetite tailings potentially limit soil formation for direct phytostabilisation. Sci Total Environ 651:191–202Google Scholar