The Rehabilitation of Huntly and Willowdale

Before rehabilitation:

After rehabilitation:
 

The Huntly mine is located near Dwellingup and was established in early 1976. Huntly is the world’s largest bauxite mine, supplying bauxite ore to Pinjarra and Kwinana Refineries. Huntly bauxite production has doubled since 1990 and currently produces around 23 million tonnes of bauxite per year.

The Willowdale mine, established in 1984, is located east of Waroona and supplies bauxite ore to the Wagerup Refinery. The Willowdale mine produces about 10 million tonnes of bauxite a year.

The ore from Huntly and Willowdale is refined to produce about 10 million tonnes of alumina each year.  This represents around 45% of Australia’s alumina production and 30% of aluminium production.  Alumina production from Alcoa’s WA refineries accounts for 11% of total world demand.

For both the Huntly and Willowdale mines, rehabilitation is one of the most important parts of the mining process. Every year about 600 hectares of the mined areas are rehabilitated across the two sites, helping restore the jarrah forest ecosystem.

Rehabilitation:

Rehabilitation processes have been fully merged into mining operations and start at the mine planning stage where significant vegetation, fauna and heritage sites are identified.

The main objective of this program is to restore 100 percent of the plant species richness to the rehabilitated areas ,15 months after rehabilitation is complete.

The pre-mining and post mining land use is the Native Jarrah forest where the aim is to  replicate native Jarrah forest ecosystem on the former mining site.

Overall the key success factors are ...

* Achieving species richness with significant work in propagating.

* Rehabilitating recalcitrant species.

Planning:

A key ecological goal of the project is to reestablish 100% of the plant species richness to the restored regions contrasted with the premined jarrah backwoods, 15 months after recovery is finished. This objective was initially accomplished in 2001 when more than 101% of herbal species were come back to the restored regions. Recovery which included planting in the 2006-07 season brought about the most astounding return of plant wealth to date, more than 108%. The outcome implies that all things considered there are more species found in a proportionate region of restoration, contrasted and the current unmined woodland.

Innovation:

Alcoa has built up various inventive methods over numerous years to guarantee the effective recovery of the area and to boost the quantity of species re-set up. Notwithstanding returning crisp topsoil, specially treated seeds are broadcast and nursery-grown plants from seeds, cuttings and tissue culture are planted.

Marrinup nursery:

Alcoa's Marrinup nursery gives seeds and plants for the recovery of mined zones. Furthermore, the nursery does seed feasibility and germination testing, and develops "ecalcitrant" plant species for other mining organizations. The nursery incorporates a tissue society (or micropropagation) research facility exclusively with the end goal of reestablishing a high differing qualities of plant species in beforehand mined regions. These special offices are world class.

Applied seed:
Every year Alcoa spreads more than five tons of local seed onto mine restoration zones. All of the seed is gathered inside roughly 20 kilometers of where it is utilized to guarantee that the same genetic diversty that was available before mining is reestablished. Marrinup nursery behind accomplishment of expansive scale jarrah woods revegetation Mine recovery in the Australian minerals industry 31 Some species require warming or smoke treatment to grow. Moreover, the planning of seeding has additionally been observed to be essential in the foundation of plants from connected seed. As opposed to customary practices, research facility and field trials recognized advantages of sowing seed in the late spring in front of fall downpours and quickly onto the worked soil. This enhances seed entombment and germination rates. Alcoa utilizes a PC controlled air seeding machine jattached to a bulldozer, spreading seeds of different species specifically onto crisply tore ground, which brings about unrivaled germination rates.

Cuttings:

Roughly 50,000 plants are developed from cuttings every year at the organization's Marrinup nursery. New shoot material is taken from wild populaces in spring every year (with proper gathering grants) to have plants prepared for planting the accompanying winter. The best shoots for cuttings are from plants that are re-growing in the wake of being singed, so accumulations are produced using late control smolders or fierce blaze regions

Tissue culture/micro propagation:

Tissue culture or micro propagation is the most troublesome and costly technique for propagating recalcitran or troublesome plant species for mine restoration. This technique is utilized when different strategies, for example, seeds or cuttings come up short. Rather than seed, these antiquated species develop and spread by conveying vegetative shoots. These vegetative adjustments are in a ideally suited to recouping from flames, brushing and dry spell, which are normal events in the common jarrah timberland. Be that as it may it makes them hard to come back to mined territories. Roughly 100,000 plants are developed from tissue culture every year for planting into restored mined zones.

Seedlings:

For some jarrah timberland plant species, seed germinates however is hard to gather and just little sums can be gotten. It is more proficient to utilize this seed to create seedlings in the nursery and plant them out rather than utilize the seed in the broadcast seed mix where the quantity of effective seedlings will be much lower. Around 50,000 plants are developed from seed and planted every year in restored ranges.

This blog is done by Jennie, Faiza and Samantha.