Mining companies are required to return quarried sites to their ‘natural character’. But is that enough?


Shaun Rosier, Te Herenga Waka — Victoria University of Wellington

New Zealand has more than 1,100 registered quarries. Some of these mined sites are small, rural operations, but a significant number are large and complex, and within a city’s urban boundaries.

As part of the resource consent application for a mining project, quarry operators are usually issued with a quarry management plan, which outlines what needs to happen to the landscape once mining has finished.

Most local government bodies require quarry operators to do little more than smooth the altered landscape, redistribute topsoil across these slopes, plant some new vegetation, and manage any onsite waterways to prevent surface erosion.

But restoring the ecology of an extracted site isn’t enough any more.

My research at the Horokiwi Quarry in Wellington explores how design-led remediation projects can restore the ecology of a mined landscape as well as creating new public landscapes that can be used for recreation.

An open quarry site
The southern half of the Horokiwi Quarry has been reshaped and the massive bench to the left entirely removed.
Author provided

Conditions of remediation

Quarry management plans currently pay attention to returning the topography of a mined site to a “natural” condition during the remediation. Quarries and mines extract material from the earth, and by necessity alter the surface dramatically.




Read more:
Afterlife of the mine: lessons in how towns remake challenging sites


Often a large amount of material has to be removed first to access the desired aggregate material or rare mineral. Once remediation begins, this material is spread across the site to create a natural appearance, suitable for revegetation. The landscape is smoothed over, pits filled in, and topsoil distributed.

Likewise, the revegetation strategy remains relatively simple. Most remediation projects rely on spraying a seed-fertiliser-mulch mix over these freshly contoured slopes. In difficult conditions, this is often paired with manual planting to establish cover for pioneer species.

These strategies typically use regionally specific plants, ideally sourcing the seed stock from the area to help establish a robust and appropriate ecology.




Read more:
The uranium mine in the heart of Kakadu needs a better clean up plan


Nature and culture

These processes are all used to restore a site back to a “natural character”, but what this means is left undefined. The Resource Management Act (RMA), under which mining resource consent applications have to be made, says miners have:

…a duty to avoid, remedy or mitigate any adverse effect on the environment arising from an activity.

While the RMA does not define this natural character condition that is to be preserved or restored, it provides some guidance in the New Zealand Coastal Policy Statement.

Here, natural character is determined to be underpinned by natural processes, elements and patterns. But as some planners and designers have made clear, this is still an unclear position.

It relies on a problematic distinction between nature and culture, where nature is something different and unaltered from humans. Or, as US environmental historian William Cronon writes:

The place where we are is the place where nature is not.

Problematic results

Most remedial works are successful from a biological point of view, leading to full or partial restoration of ecological processes. For example, the limestone quarry at Cape Foulwind has been relatively successful in its biophysical remediation. But the site is close to local communities and on a major tourist route, and could play a bigger role as a public space.

On the other hand, the remediation of the Mikonui Valley mine, on conservation land on the West Coast, has arguably been a failure, described as a “moonscape” by conservationists. The company paid a bond to the Department of Conservation to allow it to mine on public land, but it has not remediated the land to an acceptable degree, and likely never will.

Behind this is the larger issue that remediation was only seriously considered at the end of the extraction process. Doing so left little room for other design options.




Read more:
Mining powers modern life, but can leave scarred lands and polluted waters behind


Another approach to remediation

Recent research has called for a different approach, especially for quarries and mines within urban areas where landscape architects are involved throughout the entire extraction process.

Using their knowledge and skill sets could bring the extracted landscape significantly closer to a desirable outcome. It would also allow for new spaces, including parks, housing, recreation or ecological reserves.

A design plan for a remediation of the Horokiwi Quarry near Wellington
A proposal for the remediation of the Horokiwi Quarry would turn it into a regional park, connected to the surrounding suburbs and the cities of Wellington and Lower Hutt.
Author provided

This is an important shift for urban quarry sites. Establishing a design process that works in parallel with the extraction process would allow sites such as the Horokiwi Quarry to play a role in the public life of a city.

This large aggregate quarry has a remaining lifespan of 20-30 years, and presents an ideal case to develop remediation techniques that can bring the most out of this landscape.

The design proposal builds on the experience of a landscape of extreme scale and mass. Facilities such as sports fields, gathering spaces, relaxation and a mix of pathways all feed off the experience of the landscape.

At the same time, new ecological sites are established where appropriate to create a different relationship between visitors and the landscape.

A quarry near Wellington
Pathways are designed to give visitors a sense of the scale of the quarried site.
Author provided

Turning post-extraction landscapes such as the Horokiwi Quarry into public spaces confronts us with their scale and otherworldliness. It can change how we relate to the environment.

We have to remediate these sites in a way that moves us to recognise our relationship with extraction and consumption. This might not be pretty, but it is necessary.The Conversation

Shaun Rosier, Practice-based PhD Researcher in Landscape Architecture, Te Herenga Waka — Victoria University of Wellington

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Humans are polluting the environment with antibiotic-resistant bacteria, and I’m finding them everywhere



Shutterstock

Michelle Power, Macquarie University

Many of us are aware of the enormous threat of antibiotic- (or “antimicrobial”) resistant bacteria on human health. But few realise just how pervasive these superbugs are — antimicrobial-resistant bacteria have jumped from humans and are running rampant across wildlife and the environment.

My research is revealing the enormous breadth of wildlife species with superbugs in their gut bacterial communities (“microbiome”). Affected wildlife includes little penguins, sea lions, brushtailed possums, Tassie devils, flying foxes, echidnas, and a range of kangaroo and wallaby species.




Read more:
Speaking with: Dr Mark Blaskovich on antibiotic-resistant bacteria and the threat of superbugs


To combat antibiotic resistance, we need to use “One Health” — an approach to public health that recognises the interconnectedness of people, animals and the environment.

And this week’s appointment of federal Environment Minister Sussan Ley to the world’s first One Health Global Leaders Group on Antimicrobial Resistance, brings me confidence we’re finally heading in the right direction.

Where we’ve found superbugs

Tackling antimicrobial resistance with One Health requires studying resistance in bacteria from people, domesticated animals, wildlife and the environment.

Tasmanian devil standing on a rock
Tasmanian devils are among the species we’ve found harbouring resistant bacteria.
Shutterstock

Humans have solely driven the emergence and spread of antimicrobial-resistant bacteria, mainly through the overuse, and often misuse, of antibiotics.

The spread of superbugs to the environment has mainly occurred through human wastewater. Medical and industrial waste, which pollute the environment with the antibiotics themselves, worsen the issue. And the ability for antibiotic-resistant genes to be shared between bacteria in the environment has propelled antimicrobial resistance even further.




Read more:
How antibiotic pollution of waterways creates superbugs


Generally, wildlife closer to people in urban areas are more likely to carry antimicrobial-resistant bacteria, because we share our homes, food waste and water with them.

For example, our recent research showed 48% of 664 brushtail possums around Sydney and Melbourne tested positive for antibiotic-resistant genes.

Brushtailed possum in a tree
Hundreds of possums around Sydney and Melbourne have resistant bacteria.
Shutterstock

Whether animals are in captivity or the wild also plays a role in their levels of antimicrobial resistance.

For example, we found only 5.3% of grey-headed flying-foxes in the wild were carrying resistance traits. This jumps to 41% when flying-foxes are in wildlife care or captivity.

Likewise, less than 2% of wild Australian sea lions we tested had antibiotic-resistant bacteria, compared to more than 40% of those in captivity. We’ve found similar trends between captive and wild little penguins, too.

And more than 40% of brush-tailed rock wallabies in a captive breeding program were carrying antibiotic resistance genes compared to none from the wild.

So why is this a problem?

An animal with antibiotic-resistant bacteria may be harder to treat with antibiotics if it’s injured or sick and ends up in care. But generally, we’re yet to understand their full impact – though we can speculate.

Grey-headed flying-foxes hanging from a branch
We’ve found new types of resistant genes in flying-fox communities.
Shutterstock

For wildlife, resistant bacteria are essentially “weeds” in their microbiomes. These microbial weeds may disrupt the microbiomes, impairing immunity or increasing the risk of infection by other agents.

Another problem relates to how antimicrobial-resistant bacteria can spread their resistant genes to other bacteria. Sharing genes between bacteria is a major driver for new resistant bacterial strains.

We’ve been finding more types of resistant genes in an animal’s microbiome than we do in comparison to commonly studied bacteria, such as Escherichia coli. This means some wildlife bacteria may have acquired resistance genes, but we don’t know which.

Many of the wildlife species we’ve examined also carry human-associated bacterial strains — strains known to cause, for instance, diarrhoeal disease in humans. In wildlife, these bacteria could potentially acquire novel resistance genes making them harder to treat if they spread back to people.

This is something we found in grey-headed flying-fox microbiomes, which had new combinations of resistant genes. These, we concluded, originated from the outside environment.

How do we mitigate this threat?

Antimicrobial stewardship — using the best antibiotic when a bacterial infection is diagnosed, and using it appropriately — is a big part of tackling this global health issue.

This is what’s outlined in Australia’s National Antimicrobial Resistance Strategy: 2020 & Beyond, which the federal government released in March this year.

The 2020 strategy builds on a previous strategy by better incorporating the environment, in what should be a true “One Health” approach. The World Health Organisation’s appointment of Ley supports this.

Antimicrobial stewardship is equally important for those in veterinary fields as well as medical doctors. As Australia leads the world in wildlife rehabilitation, antimicrobial stewardship should be a major part of wildlife care.

For the rest of us, preventing our superbugs from spilling over to wildlife also starts with taking antibiotics appropriately, and recognising antibiotics work only for bacterial infections. It’s also worth noting you should find a toilet if you’re out in the bush (and not “go naturally”), and not leave your food scraps behind for wild animals to find.




Read more:
‘Deeply worrying’: 92% of Australians don’t know the difference between viral and bacterial infections


The 2020 strategy recognises the need for better communication to strengthen stewardship and awareness. This should include education on the issues of antimicrobial resistance, what it means for wildlife health, and how to mitigate it.

Citizens tackle antibiotic resistance in the wild.

This is something my colleagues and I are tackling through our citizen science project, Scoop a Poop, where we work with school children, community groups and wildlife carers who collect possum poo around the country to help us better understand antimicrobial resistance in the wild.

The power of working with citizens to better the health of our environment cannot be overstated.




Read more:
Explainer: what are superbugs and how can we control them?


The Conversation


Michelle Power, Associate Professor in the Department of Biological Sciences, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

One of Australia’s most famous beaches is disappearing, and storms aren’t to blame. So what’s the problem?



Shutterstock

Thomas Murray, Griffith University; Ana Paula da Silva, Griffith University; Darrell Strauss, Griffith University; Guilherme Vieira da Silva, Griffith University, and Rodger Tomlinson, Griffith University

Storms or tropical cyclones usually get the blame when Australia’s beaches suffer severe erosion. But on the New South Wales north coast at Byron Bay, another force is at play.

Over the past six months, tourists and locals have been shocked to see Byron’s famous Main Beach literally disappearing, inundated with water and debris. In October, lifesavers were forced to temporarily close the beach because they couldn’t get rescue equipment onto the sand. Resident Neil Holland, who has lived in the area for 47 years, told the ABC:

It’s the first time I’ve seen it this bad in all the time that I’ve been here, and it hasn’t stopped yet. The sand is just being taken away by the metre.

So what’s happening? To find the answer, we combined a brief analysis of satellite imagery with previous knowledge about the process behind the erosion and how it has been occurring at Byron Bay. The erosion is due to a process known as “headland bypassing”, and it is quite different to erosion from storms.

What is headland bypassing?

Headland bypassing occurs when sand moves from one beach to another around a solid obstruction, such as a rocky headland or cape. This process is mainly driven by wave energy. Along the coast of southeast Australia, waves generate currents that move sand mostly northward along the northern NSW coastline, and on towards Queensland.

However, sand does not flow evenly or smoothly along the coast: when sand arrives at a beach just before a rocky headland, it builds up against the rocks and the beach grows wider. When there is too much sand for the headland to hold, or there’s a change in wave conditions, some sand will be pushed around the headland – bypassing it – before continuing its journey up the coast.




Read more:
King tides and rising seas are predictable, and we’re not doing enough about it


This large lump of moving sand is called a “sand pulse” or “sand slug”. The sand pulse needs the right wave conditions to move towards the shore. Without these conditions, the beach in front of the pulse is deprived of sand and the waves and currents near the shore erode the beach.

Headland bypassing was first described in the 1940s. However, only about 20 years ago was it recognised as an important part of the process controlling sand moving along the coast. Since then, with better technology and more data, researchers have studied the process in more detail, and helped to shed light on how headland bypassing might affect long-term coastal planning.

Recent studies have shown wave direction is particularly important to headland bypassing. Importantly, weather patterns that produce waves are affected by climate drivers including the El Niño Southern Oscillation and the Interdecadal Pacific Oscillation. So, future changes in the way these drivers behave will affect the waves and currents that move sand along our coast, which in turn affects headland bypassing and beach erosion.

Man sitting near eroded beach
Byron Bay’s beaches have badly eroded in recent months.
Byron Shire Council

What’s happening at Byron Bay?

In October and November this year, a large amount of sand was present just north of Cape Byron, from Wategos Beach to The Pass Beach. As this sand pulse grew, Clarkes Beach, and then Main Beach, were starved of their usual sand supply and began to erode.

The sand pulse is visible on satellite images from around April 2020. Each month, it slowly moves westward into the bay. As the sand pulse grows, the beach ahead of the pulse gradually erodes. At present Main Beach is at the eroding stage.




Read more:
La Niña will give us a wet summer. That’s great weather for mozzies


Similar erosion was observed at Main Beach in the early 1990s. The beach became wider again from 1995 to 2007. From 2009 onwards, the shoreline erosion slowly began again, and became very noticeable in the past six months.

The effect of sand pulses on beach erosion is not exclusive to Byron Bay. It has been described previously in other locations, such as NSW’s Kingscliff Beach in 2011. In that case, the erosion risked damaging a nearby holiday park and bowling club.

Satellite images showing sand movement around Cape Byron
Satellite images showing sand movement around Cape Byron.
Author provided

When will this end?

Mild waves from the east to northeast, which usually occur from October to April each year, will help some of the sand pulse move onto Clarkes Beach and then further along to Main Beach. This normally happens over several months to a year. But it’s hard to say exactly when the beach will be fully restored.

This uncertainty underscores the need to better forecast these processes. This would help us to predict when bypassing sand pulses will occur and to manage beach erosion.

Climate change is expected to affect wave conditions, although the exact impact on the headland bypassing process remains unclear. However, better predictions would allow the community to be informed early about expected impacts, and officials could better manage and plan for future erosion.

Meanwhile, Byron Bay waits and watches – knowing at least that the erosion problem will eventually improve.The Conversation

People walking along Main Beach
The sand at Main Beach at Byron Bay, pictured here under good conditions, will eventually return.
AAP

Thomas Murray, Research Fellow (Coastal Management), Griffith University; Ana Paula da Silva, PhD Candidate, Griffith University; Darrell Strauss, Senior Research Fellow, Griffith University; Guilherme Vieira da Silva, Research Fellow, Griffith University, and Rodger Tomlinson, Director – Griffith Centre for Coastal Management, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.