Our Changing World

Mapping the hidden reservoirs of underground water across New Zealand and a mātauranga Māori view on moving freshwater species.

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The natural history of Marlborough's weka and disaster law: what it is and its role in disaster resilience.

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University of Canterbury's John Hopkins and Toni Collins explain disaster law and shortcomings in NZ's legal system highlighted by the Canterbury earthquakes.

The Canterbury earthquakes in 2010 and 2011, and subsequent large shakes, have drawn attention to short-comings in the way our legal system deals with disaster.

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Toni Collins and John Hopkins are used to raised eyebrows when they attend meetings with their QuakeCore colleagues.

The pair are lawyers at the University of Canterbury, whilst their colleagues are scientists and engineers.

But all of them are interested in creating a society that is more resilient when it comes to dealing with disasters, and Toni and John say that a strong well-designed legal system is an important aspect of that.

"A legal system is really just the way society organises itself," says John.

John says that disasters are commonly misunderstood.

"When people think about a disaster they think about an earthquake or a volcano, a tsunami or even a health event. But that's not the disaster - the disaster is a social event.

"The volcano that erupts when no one is there is not a disaster," says John.

"Disasters are an interaction between the hazard and what vulnerabilities you have in your society."

In Christchurch in 2011, he says, the vulnerabilities were a city built on a swamp and the way buildings were constructed.

Disaster law

Disaster law is a relatively new field which Toni says began to develop over a decade ago.

She says lawyers involved in this field are keen to ensure societies are well-prepared for possible future disasters.

Internationally, the International Federation of Red Cross and Red Crescent Societies' Disaster Law Programme, which "seeks to reduce human vulnerability by promoting legal preparedness for disasters through advocacy, technical assistance, training and research", drew up International Disaster Law Guidelines which have been adopted by all signatories to the Geneva Convention.

"The law should be prepared"

One of Toni's research projects involved the situation following the 2011 Christchurch earthquake where tenants of useable buildings in the central city Red Zone found themselves still liable to pay rent on premises they could no longer access, often in addition to paying rent on new premises.

"Their leases did not cover what should happen if their buildings were inaccessible," says Toni. "And the Property Law Act didn't provide for it either."…

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Ornithologist and author Ralph Powlesland is intimately acquainted with the weka families on the regenerating Marlborough Sounds farm where he lives.

The weka is a bird of contradictions. Curious, but wary.

Or as ornithologist Ralph Powlesland puts it in the title of his book about the flightless bird, the weka is both an opportunist and a battler.

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Twice a day, Ralph Powlesland gathers up his notebook and binoculars, and an ice cream container full of damp bread and feral goat meat, and heads out to check on the local weka.

Ralph and his wife, Mary, keep an eye on ten pairs of weka that live near their house on a Marlborough Sounds farm that is regenerating back to bush.

Ralph walks the same circuit each morning and late afternoon. His route takes him through bush, an orchard and some ungrazed paddocks, and past the vegetable gardens which are well fenced - with a roof - to prevent hungry weka making short work of the veges.

Many of the birds are banded for easy recognition, while a few have physical features that enable Ralph to identify them.

He stops in each weka territory, calling to the residents if they haven't already if come out to see him. He offers the birds some bread and some meat, and watches to see what they do with it.

A weka pair can produce two to three broods a year, which typically have one or two chicks, although Ralph comments that one pair on the property once successfully raised a clutch of five chicks.

Ralph's twice daily monitoring has given him plenty of data about the birds and insights into their behaviour.

He says he can tell from the way the birds react to the food, what stage of their breeding cycle they are up to.

"The funny thing is they can recognise quality of food," says Ralph. "Sometimes females - when they are about to lay - will refuse to eat bread, but they'll eat meat."

Adults with hungry chicks react differently to the two meal offerings as well.

"If you give bread to a female , she'll take it to the chick to eat, but if you give her some meat she'll get really hyper. She'll call and encourage the chick to be fed. It's really fascinating."

Ralph used to be a scientist with the Department of Conservation and began the weka study when he moved to the farm, on the south side of Pelorus Sound, in 2010.

The Marlborough Sounds, along with the West Coast, has long been a hot spot for weka. Ralph says the features that make it good for weka are high rainfall and a lack of ferrets…

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Liquefaction lessons from the 2011 Christchurch earthquake, and biotechnologists doing interesting things with plants.

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Biotechnologist David Leung finds ways to make plants solve environmental issues.

David Leung finds ways to make plants solve environmental issues.

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David Leung is a biotechnology researcher at the University of Canterbury.

He's looking for "technology to help plants, to use plants and to develop better plants that can help deal with environmental issues."

He's a man of many ideas, and he has many students trying to bring those ideas to fruition.

Negisa Darajeh is developing a product that removes nitrates from water, for example from effluent treatment ponds on dairy farms.

She says she is using an abundant biowaste material as feedstock for her product, but isn't able to divulge exactly what as the product is in the process of being commercialised.

At a lab scale the powder is very effective - and fast.

"Within 90 minutes we can remove 95 percent of nitrates," she says.

It's also very economical - just two grams per litre is enough to get rid of nitrates.

As well as fixing one problem, Negisa and David want to help in another area as well.

Once the nitrates have been removed, Negisa says the plan is to use the resulting powder as a slow-release fertiliser, reducing the need for synthetic fertilisers.

Trung Nguyen is culturing new potato breeds that will need less nitrogen to grow.

In the lab, she says, "the potatoes grow well and the nitrogen is like one sixteenth compared to the normal conditions."

David says he is keen to supply the new efficient, low nitrogen potato to commercial growers for field trials.

Gowtham Janardhanan is developing plants with a strong cold tolerance, so they can survive lower winter temperatures. He's intending to also develop peas that can tolerate high temperatures.

So far, his peas are doing well in a greenhouse, and the next step will be field trials.

Sabai Saw Schwe is working on ways to grow wood without growing trees.

David developed the idea after a conversation with the American Space Agency who are thinking ahead to building a space station on Mars.

Sabai has managed to convert stem calls from eucalyptus trees into xylem-like cells with strong cell walls, which David says is an excellent first step.

Listen to the full story to hear the team talk more about their work.

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Misko Cubrinovski is interested how the ground and the structures on - and in - it behave during an earthquake.

Misko Cubrinovski has spent his professional career studying liquefaction caused by earthquakes, but even he was surprised by how widespread and extensive the effects of liquefaction were following the 2011 Christchurch earthquake.

"Probably it is the largest urban liquefaction on record in the world."

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On 22 February 2011, Christchurch experienced a severe earthquake resulting in much loss of lives, destruction ... and liquefaction.

Misko Cubrinovski, a University of Canterbury geotechnical earthquake engineer, explains that liquefaction is the result of a solid medium - soil - turning into a fluid medium due to violent shaking.

Soils that are susceptible to liquefaction are generally sandy, silty or gravelly, and have to be saturated with water.

These loose, wet soils densify as a result of earthquake shaking, which creates pressure in the groundwater. This high pressure water forces soil particles apart and the soil loses its structure, says Misko, becoming a viscous fluid.

Liquefaction develops very quickly during strong earthquakes.

"During the February 2011 earthquake," says Misko, "it took two, three, four seconds to liquefy the loose soil in the eastern suburbs of Christchurch."

"Then there is a period of a minute or two when that effect of liquefaction remains very strong during which large deformations and effects occur. And then it takes hours or even days for the soil to get back to its equilibrium."

Misko says that Christchurch is still experiencing the significant consequences of liquefaction ten years after it occurred.

While liquefaction can extend 15-20 metres deep, it's most damaging consequences happen close to the ground surface, in the top five metres, says Misko.

Misko helped map and study liquefaction in Christchurch after the 2011 earthquake. He says one of the most significant discoveries from the research was that "liquefaction at large depths can prevent manifestation of liquefaction effects on the ground surface."

A deep layer of liquefaction acts as an isolation mechanism, preventing earthquake waves from reaching shallower soils.

He says this finding explained why some areas of the city that contained liquefiable soils sustained much less damage than expected.

Misko is interested in how buildings and other structures such as pipes respond to shaking and liquefaction.

Misko is part of the Quakecore Centre of Research Excellence…

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Designing a new kind of filter to treat wastewater and how to encourage people to behave in a more environmentally friendly way.

Designing a new kind of filter to treat wastewater and how to encourage people to behave in a more environmentally friendly way.

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Victoria University of Wellington's Wokje Abrahamse talks about environmental behaviour change, and projects to get people to save energy and use their cars less.

What would encourage you to take the bus instead of driving your car? Or to use less electricity in your home?

Environmental psychologist Wokje Abrahamse says there are some effective - and less effective -ways to encourage people to change their habitual behaviours.

It can be hard to take a train when you're used to driving your car - until you find the right motivation.

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Wokje Abrahamse is an environmental psychologist at Victoria University of Wellington. It's an area of research, she says, which broadly looks at peoples' relationships with the natural and built environments.

She is interested in how to foster environmental engagement and encourage people to lead more sustainable lifestyles.

"I look at what motivates people to engage in pro-environmental behaviour, what are the barriers ... and how can we know how effective behaviour change interventions are," says Wokje.

Getting people to do things differently is hard - we all know how difficult it is to change our own behaviour.

Social norms

She says people are often guided by social norms, or what other people do. For example, she says, in Wellington many people say thanks to the bus driver when they get off a bus - and newcomers to town learn it's the norm and simply copy what everyone else does.

Wokje comments that a similar thing happened in 2020 on public transport before wearing face masks became compulsory.

"I caught myself looking around, asking myself how many other people were wearing a mask and should I be wearing one?"

The use of social norms has been effectively used to encourage people to save electricity.

"When you know that you neighbours are saving energy or electricity, then studies have shown that's an effective way to encourage behaviour change," says Wokje.

Tailored information

Goal setting and feedback are useful ways to encourage behavioural change.

But simply providing information is not enough to change beliefs or behaviours, says Wokje.

Information can increase awareness, she says, but it does not automatically translate into behaviour change…

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University of Canterbury engineers plan to 3D print the next generation of wastewater treatment filters.

Researchers have $3 million and three years to come up with some new ways to clean up wastewater.

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The project - Clean Water Technology for restoring Te Mana o te Wai - is led by ecological engineer Aisling O'Sullivan, who also leads CELTS, the Centre for EcoLogical Technical Solutions, at the University of Canterbury.

The team includes 3D printing and product design expert Tim Huber, from the university's School of Product Design, Ricardo Bello-Mendoza, works with wastewater in the area of humanitarian engineering and researchers from six other institutions.

Current technology

In September 2020, new rules and regulations were introduced as part of the Government's Essential Freshwater package of reforms. Water treatment plants are now required to bring their facilities up to standard to meet the more stringent water discharge guidelines.

"Currently around 60 percent of municipal water treatment facilities that discharge to inland waterways would not meet the new regulations," says Aisling.

"Our aim is to better enable them and other industries to tackle water pollution issues in a more reliable and sustainable way."

At the moment, wastewater treatment plants use filters made from activated carbon or plastic biofilm carriers to treat wastewater. These plastic filters end up in landfill.

Developing new technology

"Our goal," says Aisling, "is to create the next generation of water treatment media, that are sustainable, that are not made from plastic, and that are going to be able to circumvent the limitations associated with filters currently."

The project is focusing on nutrients, especially nitrogen and phosphorous, along with heavy metals and pathogens, and the new filters will accumulate and immobilise these from the wastewater.

Aisling and the team plan to biofabricate the new filters using 3D printing and additive manufacturing.

"We can use a precise recipe of the materials we use - and some of those materials will be waste resources that we'll reuse," says Aisling. "We'll also be able to manipulate the shape of , the porosity of them and the chemical recipe on the outside."

Tim has experience in printing very complex 3D structures that create interesting flow patterns. He says that the key will be making structures that are very porous, as this will offer a very large surface area and increase the amount of nutrients that can be absorbed…

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