Six ways to improve water quality in New Zealand’s lakes and rivers


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Lake Tarawera, seen from its outlet, has excellent but declining water quality.
Troy Baisden, CC BY-SA

Troy Baisden, University of Waikato

Two years ago, New Zealanders were shocked when contaminated drinking water sickened more than 5,000 people in the small town of Havelock North, with a population of 14,000. A government inquiry found that sheep faeces were the likely source of bacterial pathogens, which entered an aquifer when heavy rain flooded surrounding farmland.

A second phase of the inquiry identified six principles of international drinking water security that had been bypassed. Had they been followed, the drinking water contamination would have been prevented or greatly reduced.

Here, I ask if the approach recommended by the Havelock North inquiry to prevent drinking water contamination can be extended to reduce the impacts of nutrient contamination of freshwater ecosystems.




Read more:
We all live downstream – it’s time to restore our freshwater ecosystems


Freshwater degraded and in decline

Most measures of the ecological health and recreational value of New Zealand’s lowland rivers and lakes have been rated as degraded and still declining. Intensive agriculture often cops much of the blame, but primary industry exports remain the heart of New Zealand’s economy.

The challenge posed by this trade-off between the economy and the environment has been described as both enormous, and complex. Yet it is a challenge that New Zealand’s government aims to tackle, and continues to rate as a top public concern.

An important lesson from the Havelock North inquiry is that sometimes there is no recipe – no easy list of steps or rules we can take to work through a problem. Following existing rules resulted in a public health disaster. Instead, practitioners need to follow principles, and be mindful that rules can have exceptions.

For freshwater, New Zealand has a similar problem with a lack of clear actionable rules, and I’ve mapped a direct link between the six principles of drinking water security and corresponding principles for managing nutrient impacts in freshwater.

Six principles for freshwater

Of the six principles of drinking water safety, the first is perhaps the most obvious: drinking water safety deserves a “high standard of care”. Similarly, freshwater nutrient impact management should reflect a duty of care that mirrors the scale of impacts. Our most pristine freshwater, like Lake Taupo, and water on the verge of tipping into nearly irreversible degradation, deserve the greatest effort and care.

Second, drinking water safety follows a clear logic from the starting point: “protecting the integrity of source water is paramount”. For nutrient impact management in freshwater, we must reverse this and focus on a more forensic analysis along flowpaths to the source of excess nutrients entering water. Our current approach of using estimates of sources is not convincing when tracers could point to sources in the same way DNA can help identify who was at a crime scene. We must link impacts to sources.

Third, drinking water safety demands “multiple barriers to contamination”. For freshwater, we’re better off taking a similar but different approach – maximising sequential reductions of contamination. There are at least three main opportunities, including farm management, improving drains and riparian vegetation, and enhancing and restoring wetlands. If each is 50% effective at reducing contaminants reaching waterways, the three are as good as a single barrier that reduces contamination by 90%. The 50% reductions are likely to be much more achievable and cost effective.

Managing hot spots and hot moments

The fourth principle of drinking water safety was perhaps the most dramatic failure in the Havelock North drinking water crisis: “change precedes contamination”. Despite a storm and flood reaching areas of known risk for contaminating the water supply, there were no steps in place to detect changing conditions that breached the water supply’s classification as “secure” and therefore safe.

A similar, but inverted principle can keep nutrients on farm, where we want them, and keep them out of our water. Almost all processes that lead to nutrient excess and mobilisation, as well as its subsequent removal, occur in hot spots and hot moments.

This concept means that when we look, we find that roughly 90% of excess nutrients come from less than 10% of the land area, or events that represent less than 10% of time. We can identify these hot spots and hot moments, and classify them into a system of control points that are managed to limit nutrient contamination of freshwater.

Lake Taupo, New Zealand’s largest lake, has a nitrogen cap and trade programme in place, which allocates farmers individual nitrogen discharge allowances.
from Shutterstock, CC BY-SA

Establishing clear ownership

A fifth principle for drinking water seems obvious: “suppliers must own the safety of drinking water”. Clear ownership results in clear responsibility.

Two world-leading cap-and-trade schemes created clear ownership of nutrient contaminants reaching iconic water bodies. One is fully in place in the Lake Taupo catchment, and another is still under appeal in the Lake Rotorua catchment.

These schemes involved government investment of between NZ$70 million and NZ$80 million to “buy out” a proportion of nutrients reaching the lakes. This cost seems unworkable across the entire nation. Will farmers or taxpayers own this cost, or is there any way to pass it on to investors in new, higher-value land use that reduces nutrient loss to freshwater? A successful example of shifting to higher value has been conversions from sheep and beef farming to vineyards.

As yet, the ownership of water has made headlines, but remains largely unclear outside Taupo and Rotorua when it comes to nutrient contaminants. Consideration of taxing the use of our best water could be much more sensible with a clearer framework of ownership for both water and the impacts of contaminants.

The final principle of drinking water safety is to “apply preventative risk management”. This is a scaled approach that involves thinking ahead of problems to assess risks that can be mitigated at each barrier to contamination.

For nutrient management in water, a principled approach has to start with the basic fact that water flows and must be managed within catchments. From this standpoint, New Zealand has a good case for leading internationally, because regional councils govern the environment based on catchment boundaries.

Within catchments we still have a great deal of work to do. This involves understanding how lag effects can lead to a legacy of excess nutrients. We need to manage whole catchments by understanding, monitoring and managing current and future impacts in the entire interconnected system.

The ConversationIf we can focus on these principles, government, industry, researchers, NGOs and the concerned public can build understanding and consensus together, enabling progress towards halting and reversing the declining health and quality of our rivers and lakes.

Troy Baisden, Professor and Chair in Lake and Freshwater Sciences, University of Waikato

This article was originally published on The Conversation. Read the original article.

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New Zealand puts an end to new permits for exploration of deep-sea oil and gas reserves



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New Zealand’s government will not grant any new permits for exploration of offshore oil and gas reserves.
from http://www.shutterstock.com, CC BY-SA

James Renwick, Victoria University of Wellington

The New Zealand government’s announcement that it will not issue any new permits for offshore exploration for oil and gas deposits is exciting, and a step in the right direction.

We know that we can’t afford to burn much more oil if we want to meet the Paris Agreement target of keeping global temperature rise this century well below two degrees above pre-industrial levels. Almost all of the already known reserves must stay in the ground, and there is no room to go exploring for more.

Pursuing further reserves would only lead to stranded assets and would waste time and resources in the short term.




Read more:
Why New Zealand should not explore for more natural gas reserves


Moving away from fossil fuels

New Zealand currently has 31 active permits for oil and gas exploration, and 22 of these are offshore. A program set up by the previous government invites bids each year for new onshore and offshore exploration permits. But this year it is restricted to the onshore Taranaki Basin, on the west coast of the North Island.

Complementing the move to shut down the exploration of new deep-sea fossil fuel reserves, the government’s new transport funding plan aims to reduce demand for fossil fuels by putting emphasis on public transport, cycling and walking.

This gets away from the outdated mantra of more roads and more cars that we have seen over the past decade and will tackle the transport sector, which has seen very rapid growth in emissions since 1990. This will help New Zealand onto a low-carbon pathway and promises a more people-focused future.

New Zealand is a small player in global emissions of greenhouse gases but our actions can carry symbolic weight on the world stage. Given our present position of 80% renewable electricity and an abundance of solar, wind, wave and tidal energy, if any country can become zero-carbon, surely New Zealand can. It can only benefit New Zealand – socially, economically and politically – to lead in this crucial race to stabilise the climate.




Read more:
A new approach to emissions trading in a post-Paris climate


Rising emissions

As the government announced its ban on new offshore exploration permits, the latest greenhouse gas inventory was also released, showing some good news. New Zealand’s gross emissions went down slightly from 2015 to 2016.

But gross emissions are up nearly 20% since 1990, and net emissions (actual emissions minus the “sinks” from forestry) are up 54% over that time. The main factors that contributed to the increase were dairy intensification and increased transport and energy emissions.

https://datawrapper.dwcdn.net/OLbQn/2/

Even though agriculture is still the largest source of emissions overall, energy and transport are close behind. We have seen a near-doubling in carbon dioxide emissions from road transport over the past 27 years.

It is encouraging to see a decrease in emissions from the waste sector. Per head of population, New Zealanders throw away significantly above the OECD average of rubbish, a lot of which is green waste that decomposes and releases methane, another potent but short-lived greenhouse gas.

https://datawrapper.dwcdn.net/1hCga/1/

While New Zealand emits a tiny fraction of the world’s greenhouse gases, on a per-capita basis we are sixth-highest among developed countries. We have as much responsibility as any country to reduce our emissions.

Even though emissions have risen, we are set to meet our national target for 2020 (a 5% reduction on 1990 levels) because of “carry-over” credits from the first Kyoto reporting period from 2008 to 2012. But to live up to more stringent future targets, we need a lot more action than we’ve seen over the last decade. The government plans to introduce zero-carbon legislation that will commit New Zealand to reaching the goal of carbn neutrality by 2050.

The ConversationThis will require serious investment and commitment to renewable technologies, changes in the transport sector, changes to agriculture and land use, and ultimately changes in the way we all live our lives.

James Renwick, Professor, Physical Geography (climate science), Victoria University of Wellington

This article was originally published on The Conversation. Read the original article.

A sperm race to help save one of New Zealand’s threatened birds, the sugar-lapping hihi



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A male hihi on a flowering flax bush.
Mhairi McCready, CC BY-SA

Helen Taylor

It’s likely you’ve never heard of a hihi, let alone seen one in the wild. Also known as stitchbirds, these colourful little critters are a true taonga, or treasure. They’re only found in New Zealand, and currently restricted to just seven sanctuary sites.

Without the caché of kiwi or kākāpō, hihi have gone largely ignored by conservation fans and also, crucially, by funders. Researchers have been interested in these sunny little birds for decades because of their crazy mating system and high-octane lifestyle.

A major part of hihi research goes into figuring out ways to make more hihi and get them in more places. Now, we’re combining research on hihi sperm with a major fundraising effort to try to turn this bird’s fortunes around.

Researchers are studying sperm quality to figure out what contributes to the low breeding success of the hihi, or stitchbird.

A taonga in trouble

The story of hihi is a sadly familiar one for New Zealand. They were widespread across the country’s North Island, but then humans arrived. Forest clearance and introduced mammalian predators were bad news for most of New Zealand’s native wildlife, including hihi. By 1880, hihi had been reduced to just one population on Hauturu (Little Barrier Island).

Over the past 25 years or so, conservation managers and researchers have established six new hihi populations in predator free sanctuary sites around the North Island, and numbers are on the rise, but hihi are not out of the woods yet.

At each site except for Hauturu, hihi rely on supplementary sugar-water feeding. They use the energy from the sugar water to hunt insects – their real food. On Hauturu, they get their sugar from plant nectar, but no other site in New Zealand seems to have the diverse, old growth forest that hihi need.

Catching hihi on Tiritiri Matangi, one of the island sanctuaries where they survive, to get a sperm sample.
Mhairi McCready, CC BY

Experiments have shown that when the supplementary sugar is removed, hihi numbers go into decline. The absence of decent forest isn’t the only problem for this little sugar addict though.

Small populations and dodgy sperm

The hihi’s drastic decrease in numbers after human arrival is known as a population bottleneck. When a species experiences a bottleneck, we typically see a reduction in genetic variation and an increase in mating between relatives (inbreeding).

Inbreeding can negatively affect reproduction and survival. One characteristic that seems particularly sensitive to the negative effects of inbreeding is male fertility.

Inbreeding causes dodgy sperm (and dodgy pollen) across a wide range of mammals, insects and plants. However, no one has ever really looked into how it affects sperm quality in birds.

Hihi sperm seen under a microscope.
Helen Taylor, CC BY

We know that New Zealand’s birds have relatively high rates of hatching failure. We know that hihi egg hatching rates and chick survival are negatively affected by inbreeding. But we don’t know whether this hatching failure is a result of poor male fertility, developmental problems, or a bit of both. That’s where my research comes in.

Studying bird sperm in the wild

I’m looking for links between inbreeding and sperm quality in native New Zealand birds, including the hihi. To measure bird sperm quality, we look at three things: sperm swimming speed, sperm length and the proportion of sperm with abnormalities (two heads/no tail etc.).

Getting this data from wild birds is challenging for a number of reasons.

First, you need to get the sperm. This is actually the easiest part, especially with hihi. Their mating system is so competitive that males are usually jam-packed with sperm during the mating season.

In most bird species (including hihi), males don’t have a penis. They have an opening called a cloaca, just like the female. During mating season, the area around the male’s cloaca swells as it fills up with semen. By gently massaging this swelling, I can cause a small amount of semen to pool on the surface of the cloaca and, voila! I have my sperm sample.

Massaging a male hihi to extract sperm.
Mhairi McCready, CC BY

The next challenge is measuring sperm swimming speed. Everything else can be done back at the lab, but speed has to be measured there and then and sperm have to be kept at a constant temperature, or they die. We need to run a microscope, camera and laptop to film the sperm and measure the speed. And I’m usually on a remote island or in the middle of the bush.

Working in the mobile sperm lab.
Robyn White, CC BY

To overcome these issues, I’ve designed a mobile sperm lab that runs off a small generator so I can take it pretty much anywhere. It houses my sperm speed measuring set up, plus some heat pads to keep anything that touches the sperm at a constant temperature.

The pièce de résistance is my specially designed in-bra sperm sample tube holder, which keeps samples warm against my skin before they get to the microscope.

The great hihi sperm race

In October 2017, I took my mobile sperm lab to four hihi sites: Hauturu, Trititiri Matangi, Bushy Park Sanctuary, and Zealandia.

I collected sperm and DNA samples from 128 males and am currently analysing the data to investigate the connection between sperm quality and inbreeding in this species.

At the same time, we’re attempting to address the major lack of funding for hihi conservation by encouraging people to bet on which of my 128 males will have the fastest sperm.

The ConversationThis innovative fundraiser has grabbed a fair few headlines in New Zealand and overseas, and we’ve seen bets coming in from all over the world. The race runs until April 22, 2018. To get involved, visit www.hihispermrace.nz and place your bets!

Helen Taylor, Research fellow in conservation genetics

This article was originally published on The Conversation. Read the original article.

Why New Zealand should not explore for more natural gas reserves



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The New Zealand government is introducing legislation to become zero-carbon by 2050, but will consider new permits for coal mining, offshore oil drilling and fracking on a case-by-case basis.
from shutter stock.com, CC BY-ND

Ralph Sims, Massey University

New Zealand’s new coalition government has committed to introducing zero-carbon legislation that would set the country on a course to be carbon neutral by 2050.

At the same time, it is not ruling out new permits for coal mining, offshore oil drilling and fracking during a transition away from fossil fuels.

Natural gas is often touted as a “bridging fuel” to cut the use of coal for heat and power while moving towards a low-carbon economy. Also, this week’s report by the crown research institute Scion shows that New Zealand could build a renewable low-carbon transport fuels industry by switching to biofuels instead of natural gas. Developing new gas resources in New Zealand is a shortsighted strategy that could lead to stranded assets.




Read more:
2050 climate targets: nations are playing the long game in fighting global warming


Carbon budget

Carbon dioxide (CO₂) is a long-lived greenhouse gas. Each molecule released into the atmosphere from burning fossil fuels remains there for hundreds of years. Analysis by the Intergovernmental Panel on Climate Change shows that once we reach a total of 2,900 billion tonnes of carbon dioxide (Gt CO₂) in the atmosphere, the planet will likely exceed the internationally agreed target to keep warming below two degrees above pre-industrial levels.

More than 1,900 Gt CO₂ have already been emitted since the late 19th century. We are currently adding around 33 Gt CO₂ from fossil fuel combustion and 5 Gt CO₂ from deforestation every year. The atmospheric concentration of CO₂ has now surged to more than 403 parts per million, the highest in millions of years. The planet is already around one degree warmer than the average pre-industrial temperature.

This graphic shows that we have already used up around two-thirds of the total carbon budget to avoid exceeding a two-degree average temperature rise (with a 66% chance).
IPCC, Working Group 1, 2013, CC BY-ND

The remaining carbon budget, with a 66% chance of staying below the two-degree target, is now at about 800 Gt CO₂. At the current business-as-usual rate of fossil fuel combustion and deforestation, the total budget will be exceeded within 20 to 25 years.




Read more:
Fossil fuel emissions hit record high after unexpected growth: Global Carbon Budget 2017


By then, we will have used up around two-fifths of the known global reserves of coal, oil and natural gas. The remaining three-fifths will need to stay in the ground.

Gas as a transition fuel

Natural gas is described as a “transition fuel” that cuts the use of coal. This argument, and the case for providing greater energy security, is being used to justify exploration for deep sea oil and gas in New Zealand waters.

Displacing coal by burning conventional natural gas does indeed produce lower emissions, while providing the same heat or electricity services. A coal-fired power station produces around 900-1100 g CO₂/kWh generated; a gas-fired plant produces around 450-500 g CO₂/kWh. By way of comparison, a geothermal plant varies with the field but can emit up to 50 g CO₂/kWh and emissions from other renewable energy plants vary widely with the circumstances but tend to be much lower.

However, on a life-cycle basis, any carbon dioxide reduction benefits would be partially negated by leakage of methane (CH₄), the main component of natural gas. Leakage is inevitable during the extraction, distribution and use of natural gas. It is difficult to determine the level of leakage, but it is more certain that emissions from coal or gas plants are significantly higher than from a renewable energy plant of similar generation output.

Natural gas has the potential to extend the time before the carbon budget is used up, assuming it displaces coal that would then be left in the ground. But the use of gas cannot deliver the deep cuts in emissions that will be required to stay below two degrees.

Energy security and fossil fuel subsidies

Many nations, including New Zealand, aim to improve their energy security by shifting to more indigenous fossil fuel resources to reduce their dependence on imports and widely fluctuating prices. Exploring for more gas to meet local demands at contracted prices may make good political sense in the short term, but it exacerbates climate change.

Fossil fuel exploration, production and consumption is widely subsidised by many governments. The International Energy Agency estimated the value of consumer subsidies in 2016 was over US$260 billion.

Conversely, divestment away from fossil fuel companies is growing worldwide. For example, New York City is not only intending to divest US$5 billion of its holdings in fossil fuel assets, but also plans to sue the major oil companies over their contribution to climate change.

New Zealand’s economy without more gas

In New Zealand, natural gas is used to generate electricity and heat for industries, to produce methanol (mainly for export) and other petrochemical products such as urea. It also supplies around 277,000 domestic and commercial consumers in the North Island.

Currently around 1,200,000 tonnes per year (t/yr) of coal are consumed in New Zealand, mainly for heat and electricity, emitting around 2.6 Mt CO₂/yr. If all existing coal plants and heating systems were converted to gas, around 1.3 Mt CO₂/yr of emissions would be avoided. This would contribute a little towards the 20 Mt CO₂-eq/yr of emissions reductions needed to meet New Zealand’s current 2030 target under the Paris Agreement.

However, given the Government’s target to reach net-zero emissions by mid-century, gas will ultimately need to be entirely phased out together with coal and oil products. Therefore, the overall aims for New Zealand should be to:

  • use our existing reserves of natural gas wisely in order to gain maximum long-term economic benefits by maximising the return on investments already made, as well as reducing our annual CO₂ emissions by displacing coal and minimising methane leakage

  • invest significantly in research and development in sustainable energy, including low-carbon and economically viable alternatives for the current uses of existing gas supplies

  • clarify and quantify any fossil fuel producer and consumer subsidies and remove them in the near future

  • avoid the temptation to explore and develop new gas resources even if they appear to deliver short-term economic benefits; and

  • The Conversationinvest in renewable energy technologies, including biofuels, as long as they are produced from crop and forest residues and purpose-grown forests on marginal land, as identified in the Scion report.

Ralph Sims, Professor, School of Engineering and Advanced Technology, Massey University

This article was originally published on The Conversation. Read the original article.

New Zealand’s Milford Track Under Threat From Overuse


The links below are to an article and video that take a look at New Zealand’s Milford Track and the threat it is said to be under because of overuse.

For more visit:
https://www.theguardian.com/world/2018/jan/22/worlds-finest-walk-new-zealands-milford-track-spoilt-tourists
https://www.theguardian.com/travel/video/2018/jan/22/walking-the-milford-track-new-zealands-most-popular-trail