Commentators have branded last night’s federal budget as an attempt to win over typical Australian voters concerned about the cost of living, ahead of what is expected to be a tightly fought federal election.

The budget’s big-ticket items included tax cuts and energy bill relief, plus measures to make childcare and healthcare cheaper.

There was little in the budget dedicated to stemming Australia’s environmental crises. Given this, one might assume the average voter cares little for action on conservation and curbing climate change. But is this true?

Polling suggests the clear answer is “no”. Voters consistently say they want more government action on both conservation and climate change. As the federal election looms, Labor is running out of time to show it cares about Australia’s precious natural environment.

What environmental spending was in the budget?

The main spending on the environment in last night’s budget had been announced in the weeks before. It includes:

• A$250 million over five years to help protect 30% of Australia’s land and waters by 2030

• $2 billion over 19 years to help Australia’s aluminium smelters transition to renewable electricity

• $1 billion over seven years to support new facilities and supply chains for “green” iron.

These measures are welcome. However, the overall environment spending is inadequate, given the scale of the challenges Australia faces.

Australia’s protected areas, such as national parks, have suffered decades of poor funding, and the federal budget has not rectified this. It means these sensitive natural places will remain vulnerable to harms such as invasive species and bushfires.

More broadly, Australia is failing to stem the drivers of biodiversity loss, such as land clearing and climate change. This means more native species become threatened with extinction each year.

Experts say conserving Australia’s threatened species would cost an extra $2 billion a year. Clearly, the federal budget spending of an extra $50 million a year falls well short of this.

And global greenhouse gas emissions continue to increase. This contributes to ever-worsening climate change, bringing heatwaves, more extreme fires, more variable rainfall and rising seas.

Contrary to what the federal budget priorities might suggest, Australians are concerned about these issues.

What does the average voter think about the environment?

Results from reputable polling provide insight into what the average voters want when it comes to environmental policy and spending.

When it comes to conservation, the evidence is clear. Polling by YouGov in October last year (commissioned by two environment groups) estimated that 70% of Australians think the Labor government should do more to “protect and restore nature”. The vast majority of voters (86%) supported stronger national nature laws.

Essential Research polling in October 2023 found 53% of voters think the government is not doing enough to preserve endangered species. About the same proportion said more government action was needed to preserve native forests, and oceans and rivers.

On climate change, the average voter appears to have views significantly out of step with both major parties. The Australia Institute’s Climate of the Nation report last year found 50% of voters believed the government was not doing enough to prepare for and adapt to climate impacts.

The report also found 50% of voters supported a moratorium on new coal mines in Australia, 69% support charging companies a levy for each tonne of carbon pollution they emit, and 69% are concerned about climate change.

Also in 2024, a Lowy Institute poll found 57% of Australians supported the statement that “global warming is a serious and pressing problem, and that we should take steps now to mitigate it even if it involves significant costs”.

There’s a caveat here. As the cost-of-living crisis has worsened, the issue has edged out all others in terms of voter concerns at the upcoming election.

For example, in January this year, Roy Morgan polling found 57% of voters considered cost of living one of their top-three issues of concern. Only 23% considered global warming a top-three issue.

However, global warming was still more of a concern for voters than managing the economy (22%), keeping interest rates down (19%) and reducing taxes (15%). It was tied with reducing crime (23%).

It’s also important to note that climate change and cost-of-living pressures are not separate issues. Research suggests that as climate change worsens, it will cause inflation to worsen.

Labor’s unmet election promises

The singular focus on the cost of living in last night’s federal budget means environmental spending has been neglected.

Context matters here. Labor has utterly failed to deliver its 2022 election promise to rewrite federal environmental protection laws and create an environmental protection agency.

The government could have used this budget to repair its environmental credentials going into the next election – but it didn’t. The many voters concerned about the environment might well wonder if Labor considers the environment a policy priority at all.

The upcoming election result may show whether minor parties and independents better reflect the Australian electorate’s views on this important issue.

Timothy Neal, Senior lecturer in Economics / Institute for Climate Risk and Response, UNSW Sydney

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

By the standards of pre-election budgets, this one is surprisingly modest. There are only a handful of new revenue and spending initiatives. The Budget Paper 2 book, which contains new measures, is a slim document.

In part, this is because many of the most significant new spending proposals have been announced already – support for more bulk billing, the Future Made in Australia program, funding for schools and pre-schools and the Housing Australia Future Fund.

It can be hard to discern the new initiatives from the old. For example, the budget commits the government to support wage growth by “funding wage increases for aged care workers and early childhood educators” and “advocating for increases to award wages”. It will also ban non-compete clauses (contract provisions that hinder workers from moving between employers) for low- and middle-income workers.

These should in theory significantly shift wages upwards. Yet the economic forecast for the wage price index barely moves – from 4.1% in 2023-24 to 3% in 2024-25 and 3.25% in 2025-26. That is because the forecasts had already built in assumptions on the impact of things like aged care and childcare wage rises – they aren’t new.

The non-compete reform is a new initiative and over the longer term has the potential to improve wages as people move jobs. More importantly, it will improve flexibility in the labour market and improve productivity.

Overall, the deficits are forecast to continue for the foreseeable future.

Some more tax cuts on the way

The one surprising element of the budget is tax cuts. In essence, they return some bracket creep to low- and middle-income earners for a couple of years, after which revenue estimates return to trend. Bracket creep refers to increases in tax revenues as taxpayers move into higher tax brackets.

It is one of the reasons why governments have resisted calls to index the income tax brackets to inflation. Giving back bracket creep from time to time in the form of a tax cut, especially when an election looms, is more politically attractive.

There were few savings initiatives. The main one was the old chestnut of more funding to the Australian Taxation Office for compliance.

The Taxation Office receives an additional A$999 million over four years to combat tax avoidance including non-compliance, under reporting of income and illicit tobacco. This is expected to recoup $3.2 billion over five years, while increasing payments by $1.4 billion – some of the additional tax collected will go to GST payments to the states. So in net terms therefore this is also a modest saving.

One thing to look for in every budget is the provision for “decisions taken but not yet announced”. This refers to money put aside in the budget for future announcements – such as election promises.

It is not clear what the government might have planned. Revenue drops in 2025-26, but it climbs back up again in the following two years. Spending decisions include $323 million next year, which is relatively small change in the overall budget.

For transparency, we should not have any undisclosed decisions but at least the ones in this budget are far from extravagant.

Public service numbers

On staffing in the public service, there has been a large increase since the government took office. There will be some 33,000 more public servants – the majority outside Canberra – in 2025-26 than in 2022-23. However, the rate of increase is slowing. Not all agencies have had staff increases in this budget.

Nevertheless, the government has devoted ten pages to arguments for investing in the public service, and why the public service is a valuable resource. This is probably to emphasise one of the few points of difference between it and the opposition.

The defence budget saw almost no change. The treasurer was asked in his budget lockup press conference why this was, given the uncertain geopolitical environment documented in the budget papers.

Chalmers agreed “the world is a dangerous place right now” but pointed to increases in defence spending in previous budgets and argued these had positioned Australia to respond.

One missing element of the budget is new spending to combat climate change. The threat of climate change to the budget estimates has grown significantly. This is acknowledged briefly with a half page in the budget’s “statement of risks” – “climate change is expected to have a significant impact on the budget”.

However, that impact is not quantified – possibly because of “significant uncertainty”. Yes, there is uncertainty.

But the same applies to other parts of the budget, including the international economy, which is discussed in much more depth. The climate change department is one of a handful that lose staff in this budget. It may take more severe disasters before it regains prominence in the budget papers.

Budget 2025 key announcements:

Stephen Bartos, Professor of Economics, University of Canberra

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

A bill introduced to parliament this week, if passed, would limit the government’s power to reconsider certain environment approvals when an activity is harming the environment.

It fulfils Prime Minister Anthony Albanese’s promise last month to introduce new laws to allow salmon farming to continue in Tasmania’s Macquarie Harbour. This salmon farming is currently mooted for reconsideration.

There’s no doubt Australia’s nature laws need reform. The latest review found “Australians do not trust that the EPBC Act is delivering for the environment, for business or for the community”.

But stopping the government from reconsidering a past decision is no way to fix these flaws. Reconsidering decisions is necessary if new evidence shows the activity is causing much more harm to nature, or a different kind of harm, than anticipated.

Salmon farming in Macquarie Harbour

Salmon have been farmed in Macquarie Harbour for almost 40 years, but activity has increased over the past decade.

In 2012, Tasmania’s Department of Primary Industries sought approval to expand farming in the harbour, despite possible impacts on threatened species and the Tasmanian Wilderness World Heritage Area.

But then-Environment Minister, Tony Bourke, declared no further consideration was needed and the action could proceed, because the proposal was not “a controlled action”. Under the Act, a controlled action is any activity likely to impact on a matter of national environmental significance, such as a threatened species. A project or development deemed a controlled action then requires approval from the environment minister.

However, Bourke’s decision was subject to conditions – most importantly, to ensure no significant impacts to the Maugean skate.

In late 2023, Environment Minister Tanya Plibersek received a series of requests to reconsider Bourke’s 2012 decision.

New evidence comes to light

The power to request a reconsideration is available to anyone. If substantial new information justifies it, the minister may revoke the original decision and make a new one.

In the Macquarie Harbour case, these reconsideration requests relied on scientific studies completed after 2012. One highlighted the skate’s vulnerability to changing water conditions. Another released last month showed a strong correlation between more intense salmon farming and increased extinction risk for the skate.

Plibersek has not made a decision yet. However, documents her office released under Freedom of Information laws show new evidence. This evidence supports a declaration that salmon farming in Macquarie Harbour should be reconsidered. That could trigger a full review of salmon farming in the Harbour.

However, the bill Labor has introduced would strip the minister’s powers to reconsider the earlier decision.

What does the new bill propose?

On Monday a government spokesperson said:

This bill is very specific – it’s a minor change, with extremely strict criteria – focused on giving Tasmanian workers certainty while government investments protect the Maugean Skate. The existing laws apply to everything else, including all new proposals for coal, gas, and land clearing.

But we disagree. The bill describes the circumstances in which the minister can reconsider a decision. These are cases (such as Macquarie Harbour) where an activity is allowed to proceed without full assessment and approval, in a “particular manner”. The “particular manner” must include complying with a state or territory management arrangement. For example, the salmon farmers have to comply with a Tasmanian government plan for Macquarie Harbour. Finally, these activities must be currently underway, and ongoing in that way, for at least five years.

It is not uncommon for “particular manner” decisions to require compliance with state or territory management arrangements. So the new legislation will catch more than just the Macquarie Harbour project in the “net”.

For instance, our quick search of the EPBC Act portal revealed a similar particular manner decision. This means that, after five years of operation, this second decision will also be immune from challenge.

There would be more where that came from. The bill will not only protect salmon farming in Macquarie Harbour.

What’s more, reconsideration powers have been used sparingly – there seems no reason to limit their use further. A search of the EPBC Act public portal reveals only 52 reconsideration requests since the Act began, averaging just two a year. Many of these requests were made by proponents, disgruntled with a “controlled action” decision made in relation to their own projects.

One bad bill after another

This may sound familiar, because Labor’s bill is similar to Liberal Senator Richard Colbeck’s private bill proposed in December, which also concerned protecting salmon farming jobs in Macquarie Harbour.

The Senate’s Environment and Communications Legislation Committee made a single recommendation on that bill: that it not be passed.

The majority report (from Labor, Greens and Independent senators) provided sensible reasons for recommending the bill be abandoned. It noted the power to request a reconsideration already has “appropriate safeguards”.

Furthermore, these “safeguards strike an appropriate balance by providing industry with confidence and certainty that a decision made will not be easily reversed, while allowing decisions to be reconsidered should new and significant information relating to the decision arise”.

Just four months later, these remain compelling reasons for maintaining the power to reconsider decisions.

We don’t have time to go backwards

This amendment will not achieve the comprehensive reforms the EPBC Act needs. In fact, it will actively undermine these goals. It has been rushed through after years of effort to improve nature laws, on the eve of an election, in a marginal electorate, and has been put to Parliament on the day of a budget lockup.

Despite removing this scrutiny, the bill is unlikely to resolve the controversy in Macquarie Harbour.

Phillipa C. McCormack, Future Making Fellow, Environment Institute, University of Adelaide and Justine Bell-James, Professor, TC Beirne School of Law, The University of Queensland

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

In 2022, Australia and many other nations agreed to protect 30% of their lands and waters by 2030 to arrest the rapid decline in biodiversity.

Since then, the Albanese government has protected large new areas of ocean, taking the total up to 52% of territorial waters. In tonight’s federal budget, the government is expected to announce A$250 million in funding to protect an additional 30 million hectares of land over the next five years. At present, Australia protects 22% of its lands through its National Reserve System. This would take the total to 30%.

You might expect conservationists to be ecstatic. But we’re not. Large new areas of desert and arid areas are likely to be protected under this scheme, because these areas have minimal population and are not sought after by farming. But these ecosystems are already well protected.

We have to come back to the point of the 30 by 30 agreement: protect biodiversity. That means the government has to protect representative samples of all ecosystems – including in areas sought for farming or other human uses.

Buying land is only a fraction of the task

For years, Australia’s National Reserve System of national parks, state parks and Indigenous Protected Areas has languished. The last big infusion of funding and political interest came between 2007 and 2010 under a previous Labor government, when Peter Garrett was environment minister. Then, the government expanded the reserve system, grew Indigenous Protected Areas and ensured new reserves would preserve a representative sample of Australia’s ecosystems.

Since then, conservation efforts have largely not been up to scratch. Funding has stagnated. National parks are riddled with invasive species and other environmental problems.

On funding grounds alone, the $250m announced by Environment Minister Tanya Plibersek is welcome. It is, however, just a fraction of what’s needed to properly protect the right areas.

In 2023, environmental organisations called for a $5 billion fund to buy and protect important habitat – and to pay for maintenance.

The purchase of land represents perhaps 10% of the overall cost of conservation. If you buy land and do nothing, it can be overrun by invasive species. Australia’s ever-larger number of threatened species are often threatened because of these species, as well as the growing threat of land clearing in Queensland and the Northern Territory. Fire management is another cost.

Which lands actually need protection?

As successive governments have backed away from conservation, non-government organisations such as the Australian Land Conservation Alliance, Bush Heritage Australia and Australian Wildlife Conservancy have stepped up. These organisations are doing fine work in protecting land and doing the necessary on-ground land management to safeguard threatened species and ecosystems, but they do not have access to resources at a government scale.

So how will this government funding be used? It’s likely we will see further growth in Indigenous Protected Areas – areas managed by Traditional Owners alongside authorities to protect biodiversity.

These areas are often located where low rainfall often means they are not viable for farming. This means there’s less conflict over what to do with the land. If our government is determined to meet the 30% target as quickly and cheaply as possible, we may well see more arid lands and desert protected.

When you set a target of 30% protected land by 2030, governments often see the top-line figure and aim for that alone. But the text of the international agreement stresses the need to prioritise “areas of particular importance for biodiversity”.

Governments have a choice: the easy, less effective way or the hard but effective way. The recent growth in marine protected areas suggests the government is taking the easy path. Even though the science is clear that marine parks bolster fish stocks in and outside the park, they are still controversial among fishers who believe they are being locked out.

As a result, Australia’s marine park system has made greatest gains where there are very few humans who might protest, such as quadrupling the protected areas around the very remote Heard and McDonald Islands in the sub-Antarctic region. (The government has expanded marine parks at a smaller scale closer to population centres too.)

This same story may well play out on land.

What would it look like if our government was willing to do what was necessary? It would involve actively seeking out the ecological communities in clear decline, such as native grasslands, brigalow woodlands and swamps, and buying up remaining habitat.

Saving here, clearing there

On the one hand, 22% of Australia’s land and 52% of seas come under some form of protection. But on the other, over the last two decades an area the size of Tasmania has been cleared – largely for livestock farming and mining. Satellite analyses show land clearing is actually increasing in many parts of the country.

Land clearing places further pressure on threatened species. In fact, most species considered threatened with extinction are largely in this situation because the land they live on has attributes prized by farmers or graziers, such as grass and water.

Australia’s environment faces real challenges in the next few years. Intensified land clearing, worsening climate change and whiplash drought-flood cycles, to say nothing of ballooning feral populations.

If we protect the right 30% of Australia, we have a chance to ensure most of our ecosystems have areas protected. But if we protect the wrong 30% and leave the rest open to bulldozers, we will only lock in more extinctions.

James Watson, Professor in Conservation Science, School of the Environment, The University of Queensland

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

Opposition Leader Peter Dutton says a Coalition government would introduce a long-awaited gas reservation scheme, in a budget reply speech that puts energy policy firmly at the centre of the upcoming election campaign.

On Thursday night, Dutton pledged a national gas plan that he claimed would “prioritise domestic gas supply, address shortfalls and reduce energy prices for Australians”.

Under the proposed reservation policy, gas companies would be required to divert more gas to the Australian market, rather than sell it overseas. Dutton also pledged measures to speed up development approvals for proposed gas projects.

A gas reservation scheme could help to ease supply concerns in Australia. Labor is expected to announce its own plan to reserve more gas for domestic use.

A gas reservation policy may ruffle the feathers of gas importers such as Japan. But it offers a chance to reset relations with our energy-trading partners, and position Australia as a renewable-energy powerhouse.

However, Dutton’s plan to expand gas production is a folly. No new gas projects are needed to meet Australia’s energy needs. The best way to cut energy prices is to accelerate the shift to the cheapest form of energy - which is from wind, solar and storage.

Gas reservation: a long time coming

Australia is one of the world’s biggest gas exporters. But only a fraction of gas produced here is used to power our homes and businesses. Around 80% is exported or is used to liquefy gas so it can be shipped abroad.

This means despite massive production, parts of Australia face potential gas shortages. The Australian Energy Market Operator has warned of a seasonal supply crunch in the nation’s south from 2028, as production in Bass Strait declines. Reserving gas for the domestic market instead of exporting it could close these potential gaps.

The idea of reserving gas for use in Australia is broadly popular. It is supported by Australia’s manufacturing industry, and crossbenchers including David Pocock and Jacqui Lambie.

Western Australia has had a gas reservation policy for more than a decade. However, federal policymakers have, to date, not followed suit.

This is likely in part due to opposition from the gas industry, which has traditionally fought the move, arguing it would discourage investment and create uncertainty.

There have also been concerns the policy could harm Australia’s relations with strategic partners - especially Japan.

Spotlight on Japan

Australia supplied 43% of Japan’s liquefied natural gas (LNG) in 2022. Japan has previously expressed concern about federal government moves towards diverting Australia’s gas supplies for domestic use, saying it could threaten long-established trade practices and future Japanese investment.

However, contrary to Japan’s claims, Australian gas is not needed to keep the lights on. Gas use in Japan is falling. Today, Japan on-sells more gas to other nations than it imports from Australia.

Importantly, gas contributes to dangerous climate change – both when it leaks into the atmosphere as methane, and when it is burned, releasing carbon dioxide and other pollutants.

Around a quarter of Australia’s greenhouse gas emissions come from the production and use of gas. Australian gas burned overseas is also responsible for substantial carbon emissions in other countries .

Tokyo’s finance for gas projects in Australia is slowing the shift away from fossil fuels and diverting investment, workforce, and supply-chain capacity away from clean energy industries.

Diverting Australian gas to meet local needs would help reset trading relations in our region. Australia’s economic prospects are tied to embracing our potential as a clean energy superpower. This requires signalling to our trading partners our intention to shift away from gas extraction for export.

No new gas is needed

In his budget reply, Dutton pledged to audit development-ready gas projects with a focus on the southern states and, as previously announced, fast-track a decision on Western Australia’s Northwest Shelf gas project.

A Coalition government, if elected, would also:

• invest A$1 billion into a critical gas infrastructure fund
• increase gas pipeline and storage capacity
• prevent gas companies from prolonged delays in drilling offshore gas fields.

However, Australia does not need any new gas projects. We only use a fraction of what we produce.

What’s more, evidence suggests more gas production will not bring prices down. East coast gas production has doubled over the past decade even as gas prices have tripled.

Keeping more gas onshore may help with energy prices. But the best way to reduce power bills is to shift to the cheapest form of electricity generation - which is renewables, not gas.

Australia’s gas use is declining as we move to cleaner, cheaper and more efficient types of energy for homes and businesses.

On the east coast, gas consumption has declined by 25% in the past decade. Just last week the Australian Energy Market Operator found gas demand is falling faster than anticipated.

Reducing gas use even faster would avoid potential seasonal shortages.

Gas has a small, short-term role as Australia switches to renewables, smoothing out electricity supplies when demand exceeds generation from wind, solar and energy storage.

But the gas won’t be used very often. And a looming surge in batteries to store renewable energy is also likely to displace gas generation at peak times.

Research suggests production from Australia’s existing projects through to 2035 could meet our remaining gas needs for 60 years.

A domestic reservation policy could ensure this gas is used to avoid potential supply gaps.

Our shared clean energy future

With a national gas reservation scheme on the table no matter who wins the election, Australia will have some tough conversations ahead with international customers – especially Japan.

However both Australia and Japan have committed to cut emissions over the next decade and achieve net-zero emissions in their economies by 2050.

Gas will play an ever-dwindling role in both countries in coming years, as it is replaced by cleaner forms of energy from wind, solar and storage.

Government efforts to manage the energy transition should not encourage new gas projects. Instead, it should position Australia at the forefront of the clean energy revolution.

Wesley Morgan, Research Associate, Institute for Climate Risk and Response, UNSW Sydney

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

You might know South Australia’s iconic Coorong from the famous Australian children’s book, Storm Boy, set around this coastal lagoon.

This internationally important wetland is sacred to the Ngarrindjeri people and a haven for migratory birds. The lagoon is the final stop for the Murray River’s waters before they reach the sea. Tens of thousands of migratory waterbirds visit annually. Pelicans, plovers, terns and ibises nest, while orange-bellied parrots visit and Murray Cod swim. But there are other important inhabitants – trillions of microscopic organisms.

You might not give much thought to the sedimentary microbes of a lagoon. But these tiny microbes in the mud are vital to river ecosystems, quietly cycling nutrients and supporting the food web. Healthy microbes make for a healthy Coorong – and this unassuming lagoon is a key indicator for the health of the entire Murray-Darling Basin.

For decades, the Coorong has been in poor health. Low water flows have concentrated salt and an excess of nutrients. But in 2022, torrential rains on the east coast turned into a once-in-a-century flood, which swept down the Murray into the Coorong.

In our new research, we took the pulse of the Coorong’s microbiome after this huge flood and found the surging fresh water corrected microbial imbalances. The numbers of methane producing microbes fell while beneficial nutrient-eating bacteria grew. Populations of plants, animals and invertebrates boomed.

We can’t just wait for irregular floods – we have to find ways to ensure enough water is left in the river to cleanse the Coorong naturally.

Rivers have microbiomes, just like us

Our gut microbes can change after a heavy meal or in response to dietary changes.

In humans, a sudden shift in diet can encourage either helpful or harmful microbes.

In the same way, aquatic microbes respond to changes in salinity and freshwater flows. Depending on what changes are happening, some species boom and others bust.

As water gets saltier in brackish lagoons, communities of microbes have to adapt or die. High salinity often favours microbes with anaerobic metabolisms, meaning they don’t need oxygen. But these tiny lifeforms often produce the highly potent greenhouse gas methane. The microbes in wetlands are a large natural source of the gas.

While we know pulses of freshwater are vital for river health, they don’t happen often enough. The waters of the Murray-Darling Basin support most of Australia’s irrigated farming. Negotiations over how to ensure adequate environmental flows have been fraught – and long-running. Water buybacks have improved matters somewhat, but researchers have found the river basin’s ecosystems are not in good condition.

The Coorong is out of balance

A century ago, regular pulses of fresh water from the Murray flushed nutrients and sediment out of the Coorong, helping maintain habitat for fish, waterbirds and the plants and invertebrates they eat. While other catchments discharge into the Coorong, the Murray is by far the major water source.

Over the next decades, growth in water use for farming meant less water in the river. In the 1930s, barrages were built near the river’s mouth to control nearby lake levels and prevent high salinity moving upstream in the face of reduced river flows.

Major droughts have added further stress. Under these low-flow conditions, salt and nutrients get more and more concentrated, reaching extreme levels due to South Australia’s high rate of evaporation.

In response, microbial communities can trigger harmful algae blooms or create low-oxygen “dead zones”, suffocating river life.

The big flush of 2022

In 2022, torrential rain fell in many parts of eastern Australia. Rainfall on the inland side of the Great Dividing Range filled rivers in the Murray-Darling Basin. That year became the largest flood since 1956.

We set about recording the changes. As the salinity fell in ultra-salty areas, local microbial communities in the sediment were reshuffled.

The numbers of methane-producing microbes fell sharply. This means the floods would have temporarily reduced the Coorong’s greenhouse footprint.

When we talk about harmful bacteria, we’re referring to microbes that emit greenhouse gases such as methane, drive the accumulation of toxic sulfide (such as Desulfobacteraceae), or cause algae blooms (Cyanobacteria) that can sicken people, fish and wildlife.

During the flood, beneficial microbes from groups such as Halanaerobiaceae and Beggiatoaceae grew rapidly, consuming nutrients such as nitrogen, which is extremely high in the Coorong. This is very useful to prevent algae blooms. Beggiatoaceae bacteria also remove toxic sulfide compounds.

The floods also let plants and invertebrates bounce back, flushed out salt and supported a healthier food web.

On balance, we found the 2022 flood was positive for the Coorong. It’s as if the Coorong switched packets of chips for carrot sticks – the flood pulse reduced harmful bacteria and encouraged beneficial ones.

While the variety of microbes shrank in some areas, those remaining performed key functions helping keep the ecosystem in balance.

From 2022 to 2023, consistent high flows let native fish and aquatic plants bounce back, in turn improving feeding grounds for birds and allowing black swans to thrive.

Floods aren’t enough

When enough water is allowed to flow down the Murray to the Coorong, ecosystems get healthier.

But the Coorong has been in poor health for decades. It can’t just rely on rare flood events.

Next year, policymakers will review the Murray-Darling Basin Plan, which sets the rules for sharing water in Australia’s largest and most economically important river system.

Balancing our needs with those of other species is tricky. But if we neglect the environment, we risk more degradation and biodiversity loss in the Coorong.

As the climate changes and rising water demands squeeze the basin, decision-makers must keep the water flowing for wildlife.

Christopher Keneally, Post-Doctoral Research Fellow in Environmental Microbiology, University of Adelaide; Justin Brookes, Director, Water Research Centre, University of Adelaide; Matt Gibbs, Senior Research Scientist in Hydrology, CSIRO, and Sophie Leterme, Professor of Biology, Flinders University

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

Picture an ocean world so deep and dark it feels like another planet – where creatures glow and life survives under crushing pressure.

This is the midwater zone, a hidden ecosystem that begins 650 feet (200 meters) below the ocean surface and sustains life across our planet. It includes the twilight zone and the midnight zone, where strange and delicate animals thrive in the near absence of sunlight. Whales and commercially valuable fish such as tuna rely on animals in this zone for food. But this unique ecosystem faces an unprecedented threat.

As the demand for electric car batteries and smartphones grows, mining companies are turning their attention to the deep sea, where precious metals such as nickel and cobalt can be found in potato-size nodules sitting on the ocean floor.

Deep-sea mining research and experiments over the past 40 years have shown how the removal of nodules can put seafloor creatures at risk by disrupting their habitats. However, the process can also pose a danger to what lives above it, in the midwater ecosystem. If future deep-sea mining operations release sediment plumes into the water column, as proposed, the debris could interfere with animals’ feeding, disrupt food webs and alter animals’ behaviors.

As an oceanographer studying marine life in an area of the Pacific rich in these nodules, I believe that before countries and companies rush to mine, we need to understand the risks. Is humanity willing to risk collapsing parts of an ecosystem we barely understand for resources that are important for our future?

Mining the Clarion-Clipperton Zone

Beneath the Pacific Ocean southeast of Hawaii, a hidden treasure trove of polymetallic nodules can be found scattered across the seafloor. These nodules form as metals in seawater or sediment collect around a nucleus, such as a piece of shell or shark’s tooth. They grow at an incredibly slow rate of a few millimeters per million years. The nodules are rich in metals such as nickel, cobalt and manganese – key ingredients for batteries, smartphones, wind turbines and military hardware.

As demand for these technologies increases, mining companies are targeting this remote area, known as the Clarion-Clipperton Zone, as well as a few other zones with similar nodules around the world.

So far, only test mining has been carried out. However, plans for full-scale commercial mining are rapidly advancing.

Exploratory deep-sea mining began in the 1970s, and the International Seabed Authority was established in 1994 under the United Nations Convention on the Law of the Sea to regulate it. But it was not until 2022 that The Metals Company and Nauru Ocean Resources Inc. fully tested the first integrated nodule collection system in the Clarion-Clipperton Zone.

The companies are now planning full-scale mining operations in the region and expect to submit their application to the ISA by June 27, 2025. The ISA will convene in July 2025 to discuss critical issues such as mining regulations, guidelines and benefit-sharing mechanisms.

The proposed mining process is invasive. Collector vehicles scrape along the ocean floor as they scoop up nodules and stir up sediments. This removes habitats used by marine organisms and threatens biodiversity, potentially causing irreversible damage to seafloor ecosystems. Once collected, the nodules are brought up with seawater and sediments through a pipe to a ship, where they’re separated from the waste.

The leftover slurry of water, sediment and crushed nodules is then dumped back into the middle of the water column, creating plumes. While the discharge depth is still under discussion, some mining operators propose releasing the waste at midwater depths, around 4,000 feet (1,200 meters).

However, there is a critical unknown: The ocean is dynamic, constantly shifting with currents, and scientists don’t fully understand how these mining plumes will behave once released into the midwater zone.

These clouds of debris could disperse over large areas, potentially harming marine life and disrupting ecosystems. Picture a volcanic eruption – not of lava, but of fine, murky sediments expanding throughout the water column, affecting everything in its path.

The midwater ecosystem at risk

As an oceanographer studying zooplankton in the Clarion-Clipperton Zone, I am concerned about the impact of deep-sea mining on this ecologically important midwater zone. This ecosystem is home to zooplankton – tiny animals that drift with ocean currents – and micronekton, which includes small fish, squid and crustaceans that rely on zooplankton for food.

Sediment plumes in the water column could harm these animals. Fine sediments could clog respiratory structures in fish and feeding structures of filter feeders. For animals that feed on suspended particles, the plumes could dilute food resources with nutritionally poor material. Additionally, by blocking light, plumes might interfere with visual cues essential for bioluminescent organisms and visual predators.

For delicate creatures such as jellyfish and siphonophores – gelatinous animals that can grow over 100 feet long – sediment accumulation can interfere with buoyancy and survival. A recent study found that jellies exposed to sediments increased their mucous production, a common stress response that is energetically expensive, and their expression of genes related to wound repair.

Additionally, noise pollution from machinery can interfere with how species communicate and navigate.

Disturbances like these have the potential to disrupt ecosystems, extending far beyond the discharge depth. Declines in zooplankton populations can harm fish and other marine animal populations that rely on them for food.

The midwater zone also plays a vital role in regulating Earth’s climate. Phytoplankton at the ocean’s surface capture atmospheric carbon, which zooplankton consume and transfer through the food chain. When zooplankton and fish respire, excrete waste, or sink after death, they contribute to carbon export to the deep ocean, where it can be sequestered for centuries. The process naturally removes planet-warming carbon dioxide from the atmosphere.

More research is needed

Despite growing interest in deep-sea mining, much of the deep ocean, particularly the midwater zone, remains poorly understood. A 2023 study in the Clarion-Clipperton Zone found that 88% to 92% of species in the region are new to science.

Current mining regulations focus primarily on the seafloor, overlooking broader ecosystem impacts. The International Seabed Authority is preparing to make key decisions on future seabed mining in July 2025, including rules and guidelines relating to mining waste, discharge depths and environmental protection.

These decisions could set the framework for large-scale commercial mining in ecologically important areas such as the Clarion-Clipperton Zone. Yet the consequences for marine life are not clear. Without comprehensive studies on the impact of seafloor mining techniques, the world risks making irreversible choices that could harm these fragile ecosystems.

Alexus Cazares-Nuesser, Ph.D. Candidate in Biological Oceanography, University of Hawaii

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

Confronting images of dead seadragons, fish and octopuses washed up on South Australian beaches – and disturbing reports of “more than 100” surfers and beachgoers suffering flu-like symptoms after swimming or merely breathing in sea spray – attracted international concern last week.

Speculation about the likely cause ranged from pollution and algae to unusual bacterial infections or viruses. Today we can reveal the culprit was a tiny – but harmful – type of planktonic algae called Karenia mikimotoi.

The SA government sent us water samples from Waitpinga Beach, Petrel Cove Beach, Encounter Bay Boat Ramp and Parsons Headland on Tuesday. We studied the water under the microscope and extracted DNA for genetic analysis.

Our results revealed high numbers of the tiny harmful algal species – each just 20 microns in diameter (where one micron is one thousandth of a millimetre). While relatively common in Australian coastal waters, blooms of K. mikimotoi occur only sporadically. But similar harmful algal blooms and fish kills due to K. mikimotoi have happened in the past, such as the 2014 bloom in Coffin Bay, SA. And this latest one won’t be the last.

Harmful algal blooms

Single-celled, microbial algae occur naturally in seawater all over the world.

They are also called phytoplankton, because they float in the water column and photosynthesise like plants. “Phyto” comes from the Greek word for plant and “plankton” comes from the Greek word for wanderer, which relates to their floating movement with ocean currents and tides.

Like plants on land, the microalgae or phytoplankton in the ocean capture sunlight and produce up to half the oxygen in our atmosphere. There are more than 100,000 different species of microalgae. Every litre of seawater will normally contain a mixed group of these different microalgae species.

But under certain conditions, just a single species of microalgae can accumulate in one area and dominate over the others. If we are unlucky, the dominant species may be one that produces a toxin or has a harmful effect.

This so-called “harmful algal bloom” can cause problems for people and for marine life such as fish, invertebrates such as crabs, and even marine mammals such as whales and seals.

There are hundreds of different species of harmful algae. Each produces its own type of toxin with a particular toxic effect.

Most of these toxic chemical compounds produced by harmful algae are quite well known, including neurotoxins that affect the brain. But others are more complicated, and the mechanisms of toxicity are poorly understood. This can make it more difficult to understand the factors leading to the deaths of fish and other marine life. Unfortunately, the toxins from K. mikimotoi fall into this latter category.

Introducing Karenia mikimotoi

The species responsible for recent events in SA beaches, K. mikimotoi, causes harmful algal blooms in Asia, Europe, South Africa and South America, as well as Australia and New Zealand. These blooms all caused fish deaths, and some also caused breathing difficulties among local beachgoers.

The most drastic of these K. mikimotoi blooms have occurred in China over the past two decades. In 2012, more than 300 square kilometres of abalone farms were affected, causing about A$525 million in lost production.

Explaining the toxic effects

Microalgae can damage the gills of fish and shellfish, preventing them from breathing. This is the main cause of death. But some studies have also found damage to the gastrointestinal tracts and livers of fish.

Tests using fish gill cells clearly show the dramatic toxic effect of K. mikimotoi. When the fish gill cells were exposed to intact K. mikimotoi cells, after 3.5 hours more than 80% of the fish cells had died.

Fortunately, the toxin does not persist in the environment after the K. mikimotoi cells are dead. So once the bloom is over, the marine environment can recover relatively quickly.

Its toxicity is partly due to the algae’s production of “reactive oxygen species”, reactive forms of oxygen molecules which can cause the deaths of cells in high doses. K. mikimotoi cells may also produce lipid (fat) molecules that cause some toxic effects.

Finally, a very dense bloom of microalgae can sometimes reduce the amount of dissolved oxygen in the water column, which means there is less oxygen for other marine life.

The human health effects are not very well known but probably relate to the reactive oxygen species being an irritant.

K. mikimitoi cells can also produce “mucilage”, a type of thick, gluey substance made of complex sugars, which can accumulate bacteria inside it. This can cause “sea foam”, which was evident on beaches last week.

Unanswered questions remain

A question for many people is whether increasing water temperatures make blooms of K. mikimotoi more likely.

Another concern is whether nutrient runoff from farms, cities and aquaculture could cause more harmful algal blooms.

Unfortunately, for Australia at least, the answer to these questions is we don’t know yet. While we know some harmful algal blooms do increase when nutrient runoff is higher, others actually prefer fewer nutrients or colder temperatures.

We do know warmer water species seem to be moving further south along the Australian coastline, changing phytoplankton species abundance and distribution.

While some microalgal blooms can cause bioluminescence that is beautiful to watch, others such as K. mikimotoi can cause skin and respiratory irritations.

If you notice discoloured water, fish deaths or excessive sea foam along the coast or in an estuary, avoid fishing or swimming in the area and notify local primary industry or environmental authorities in your state.

Shauna Murray, Professor; Faculty of Science, University of Technology Sydney and Greta Gaiani, Chancellor's Postdoctoral Research Fellow, School of Life Sciences, University of Technology Sydney

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

The Adelaide Hills are experiencing severe water shortages. The root cause? A prolonged dry period and not enough water tankers to meet unprecedented demand from people not connected to the mains water supply.

Thousands of residents and farmers are hurting as dams, tanks and streams dry up. Water tankers are becoming a common sight, carting in desperately needed water. People are waiting weeks for expensive water deliveries.

The South Australian government has set up emergency water collection points to cope with the demand from off-grid families. More water tankers have been secured. But despite recent rain, the situation is far from over.

We found rainfall and flows into Adelaide’s reservoirs are at their lowest levels in 40 years. Reservoir levels have dropped to 44% – the lowest for more than 20 years.

Adelaide is not currently at risk of running out of water; the state government built a desalination plant after the Millennium Drought. Production at the desal plant is four to six times higher than usual to meet demand. Without the desal plant and water from the River Murray, the city would be under severe water restrictions.

But the crisis shows many off-grid families, farms and businesses need new options to plan for the future.

Global water stress

This is not the first time entire communities have run out of water.

Cape Town in South Africa nearly ran out of water in 2018. The city of nearly 4 million people was weeks away from “Day Zero”.

In Australia, several regional and rural country towns have hit their own Day Zero. Stanthorpe in Queensland officially ran out of water in January 2020. Truckloads of water were carted into town every day to meet residential demand.

Scientists have coined a new term, “hydroclimate whiplash”, to describe the rapid swings between intensely wet and dangerously dry weather currently occurring across the globe. This climate volatility amplifies natural hazards such as flash floods, wildfires, landslides and disease.

The January wildfires in Los Angeles happened when two wet winters were followed by an extremely dry autumn and winter, providing plenty of dry fuel for fire.

These aren’t isolated events. The global water crisis didn’t go away.

The bigger picture

What’s happening in the Adelaide Hills – and in other very dry places worldwide – demonstrates the need for careful, long-term water security planning.

The United Nations Sustainable Development Goal 6 is to “ensure availability and sustainable management of water and sanitation for all”. Water stress already affects more than 2 billion people – more than a quarter of the world’s population.

By 2030, the UN predicts 2 billion people will still be living without safely managed drinking water, 3 billion without safely managed sanitation, and 1.4 billion without basic hygiene services.

For many, this is literally a life-or-death matter.

Investing in water security

CSIRO is collaborating with industry, government and research organisations on research to overcome drought and build resilience for regional Australia. Our researchers are testing how well each of these strategies might work in different regions during extended dry periods. We calculate how much water can be collected and stored during the driest periods on record.

Rainfall over Norfolk Island, a subtropical island in the Pacific Ocean roughly 1,500km southeast of Brisbane, has declined by 11% since 1970, with long runs of dry years in recent decades. The future is likely to be drier still.

Our Norfolk Island Water Resource Assessment explored ways to help the community determine how to adapt and build resilience to drought.

Since this project finished in 2020, residential and commercial rainwater tanks have been upgraded and a new seawater desalination plant installed. Other options to diversify water supplies included sharing groundwater bores, capturing runoff in gully dams, managing vegetation water use, and storing water underground.

Excess water from rainwater or recycled wastewater can sometimes be stored underground in natural reservoirs called aquifers for use during drought. This is called “water banking” or “managed aquifer recharge”. The technique has been developed over the past 20 years and used to safely store water underground across Australia and overseas.

Brackish (salty) groundwater is a potential water source that could be unlocked during drought. A National Water Grid funded project is investigating ways to use groundwater that would normally be too salty, along with renewable energy to power inland desalination plants. The project is investigating the prospect of using brackish groundwater across Western Australia for the first time.

A call to action

The Adelaide Hills water crisis is a microcosm of a global issue. It’s a reminder action is needed now to secure our water future. Not when the water runs out.

Deeper groundwater bores, water tankers on standby and bigger water storages are all potentially part of the portfolio of emergency plans. And due to climate change, the Adelaide Hills water crisis will happen again if we are unprepared. It is a question of when, not if.

We have also seen the catastrophic effects of drought in Los Angeles – a tinderbox waiting to burn, and insufficient water on hand to fight the fires. We can and must prepare for natural disasters today. These are not unforeseen consequences. They are not “unknown unknowns”. We know them today. We will have no excuse when this happens.

By adopting more sustainable water management policies and practices in the longer term, we can make sure the spectre of Day Zero does not become real for more communities around the world.

With thanks to CSIRO Senior Research Scientist and Hydrologist Matt Gibbs and Principal Experimental Scientist in Hydrogeology Andrew Taylor.

Kate Holland, Principal Research Scientist, Water Security, CSIRO and Craig T. Simmons, Chief Scientist, South Australia and Pro Vice-chancellor, University of Newcastle

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

Ants are among nature’s greatest success stories, with an estimated 22,000 species worldwide.

Tropical Australia in particular is a global hotspot for ant diversity. Some researchers believe it could hold some of the richest ant biodiversity on the planet, with an estimated 5,000 species in the tropics alone.

But if ants are so successful out in nature, why do they so often turn up in our homes and even upper-level apartments?

And what can we do to keep them out?

There’s probably an ant near you right now

Ants dominate the planet in terms of sheer abundance.

At any given moment, there are an estimated 20 quadrillion ants alive — that’s 20 followed by 15 zeros.

In fact, for every human being, there are roughly 2.5 million ants.

So the short answer to “Why are there ants in my house?” is simply this: there are a lot of ants.

We live on a planet where ants outnumber us by an almost unimaginable margin. The fact that a few occasionally wander into our homes shouldn’t come as a surprise.

Ants work from home (yours, that is)

Ants owe much of their success to their highly social nature.

Within the colony, some individuals (female queens and male drones) are responsible for reproduction, while others (workers) are busy caring for the young, cleaning or foraging for food. Workers ants are always female.

Ant colonies do not have leaders. They are an excellent example of collective behaviour and swarm intelligence, where individuals following relatively simple rules can collectively achieve far more than any individual could alone.

Just as the individual neurons in your brain can’t compose music, play football, or read articles, the brain as a whole can achieve all these feats and more.

Colonies of co-operating ants are capable of amazingly sophisticated behaviours such as:

• building efficient trail networks
• building living bridges with their bodies, and
• “farming” fungi and aphids (small, sap-sucking insects that feed on plants).

Ants even outperform humans on some cooperative cognition tasks.

The highly social nature of ants is a big part of their success — and a key reason why they are so good at finding their way into our homes.

Each colony contains thousands of intrepid workers, many of which are constantly searching for new food sources. If even a single ant discovers a valuable resource in your home, it can quickly share that information with its nest mates.

Different ant species use different methods of communication, but the ones that most often invade our homes tend to use “pheromone trails”.

When an ant finds a food source, she returns to her nest leaving little drops of pheromones as she goes; this trail guides other ants from their nest directly to the food source.

This highly efficient communication system means a single ant can rapidly recruit thousands of its nest mates to any food it finds.

Ants may also come inside in search of water, particularly when the weather is hot.

Some species prefer to build their nests in humid environments, which might explain why they are often found in bathrooms.

I once discovered an entire colony of sugar ants nesting inside my aquarium filter! The combination of high humidity and an enclosed structure made it an ideal place to build a nest.

On the flip side, heavy rains can flood ant nests, prompting colonies to seek drier ground — sometimes leading them straight into our homes.

I live in an upper-floor apartment. How did ants get in?

Many ant species are exceptional climbers, thanks to tiny adhesive pads and fine hairs on their feet.

These specialised structures allow ants to stick to walls and find footholds even on surfaces that appear smooth to the human eye.

Remarkably, some canopy-dwelling ants have evolved a behaviour known as “controlled descent” which protects them when they fall. By adjusting the position of their abdomens, falling ants can steer their trajectory, directing themselves back toward the tree trunk and safety.

How do I keep ants out of my house?

Well, good luck. No matter what you do, ants will probably enter your house at one time or another.

Finding a few ants in your home doesn’t mean your house is dirty. We simply live on a planet that is absolutely teeming with ants.

To minimise unwanted ant visits, start by eliminating any potential food sources that could feed a hungry ant.

Store all food in sealed airtight containers, clean behind the fridge and inside/under the toaster, avoid leaving pet food out longer than needed and make sure your bins are securely sealed.

Ants have tiny stomachs, so even small crumbs or the residue from spilled sugary drinks can be enough to entice them back.

If ants seem to be following each other in a line, try disrupting their chemical trail using vinegar or bleach. Be warned, however: ants are very good at repairing broken trail networks.

Seal any small cracks or entrance points that might allow ants to get into your home and make sure your windows and doors have well-fitting fly screens.

Insecticidal baits can kill ant colonies, but before you deploy the nuclear option, ask yourself: what harm are the ants really doing?

Most common home-invading ants do not sting and are pretty harmless. They can usually be redirected simply by removing their food source.

Ants are nature’s clean-up crew, tirelessly scavenging waste and helping to maintain a healthy, balanced ecosystem.

They also play important roles as predators and seed dispersers.

Before reaching for insecticides, consider whether a few ants in your house are truly a problem.

Tanya Latty, Associate Professor, School of Life and Environmental Sciences, University of Sydney

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

Plant behaviour may seem rather boring compared with the frenetic excesses of animals. Yet the lives of our vegetable friends, who tirelessly feed the entire biosphere (including us), are full of exciting action. It just requires a little more effort to appreciate.

One such behaviour is the dynamic opening and closing of millions of tiny mouths (called stomata) located on each leaf, through which plants “breathe”. In this process they let out water extracted from the soil in exchange for precious carbon dioxide from the air, which they need to produce sugar in the sunlight-powered process of photosynthesis.

Opening the stomata at the wrong time can waste valuable water and risk a catastrophic drying-out of the plant’s vascular system. Almost all land plants control their stomata very precisely in response to light and humidity to optimise growth while minimising the damage risk.

How plants evolved this extraordinary balancing act has been the subject of considerable debate among scientists. In a new paper published in PNAS we used lasers to find out how the earliest stomata may have operated.

Tiny valves, global consequences

Much depends on the way stomata behave: plant productivity, sensitivity to drought, and indeed the pace of the global carbon and water cycles.

However, they are difficult to observe in action. Each stomata is like a tiny, pressure-operated valve. They have “guard cells” surrounding an opening or pore which lets water vapour out and carbon dioxide in.

When fluid pressure increases inside the stomata’s guard cells, they swell up to open the pore. When pressure drops, the cells deflate and the pore closes. To understand stomata behaviour, we wanted to be able to measure the pressure in the guard cells – but it’s not easy.

Lasers, bubbles and evolution

Enter Craig Brodersen of Yale University with a newly developed microscope-guided laser. It can create microscopic bubbles inside the individual cells that operate the stomatal pore.

When Brodersen spent a sabbatical at the University of Tasmania (where I am based), we found we could determine the pressure inside stomatal cells by tracking the size of these bubbles and how quickly they collapsed. This involved theoretical calculations guided by bubble expert Philippe Marmottant, of the French National Centre for Scientific Research (CNRS) in Grenoble.

This new tool gave us the perfect opportunity to explore how the behaviour of stomata is different among major plant groups. The aim was to test our hypothesis that the evolution of stomatal behaviour follows a predictable trajectory through the history of plant evolution.

We argue it began with a relatively simple ancestral passive control state, currently represented in living ferns and lycophytes, and developed to a more active hormonal control mechanism seen in modern conifers and flowering plants.

Against this hypothesis, some researchers have previously reported complex behaviours in some of the most ancient of stomata-bearing plants, the bryophytes. We wanted to test this finding using our newly developed laser instrument.

400 million years of development

What we found was firstly that our laser pressure probe technique worked extremely well. We made nearly 500 measurements of stomatal pressure dynamics in the space of a few months. This was a marked improvement on the past 45 years, in which fewer than 30 similar measurements had been made.

Secondly, we found that the stomata of our representative bryophytes (hornworts and mosses) lacked even the most basic responses to light found in all other land plants.

This result supported our earlier hypothesis that the first stomata found in ancestors of the modern bryophytes 450 million years ago should have been very simple valves. They would have lacked the complex behaviours seen in modern flowering plants.

Our results suggest that stomatal behaviour has changed substantially through the process of evolution, highlighting critical changes in functionality that are preserved in the different major land plant groups that currently inhabit the Earth.

How plants will survive the future

We can now say with confidence that stomata in mosses, ferns, conifers and flowering plants all behave in very different ways. This has an important corollary: they will all respond differently to the heaving changes in atmospheric temperature and water availability that they face now and into the near future. Predicting stomatal behaviour in the future will help us to predict these impacts and highlight plant vulnerability.

In terms of agricultural benefit, our new laser method should be fast and sensitive enough to reveal even small differences in the the behaviour of closely related plants. This may help to identify crop variants that use water in a more efficient or productive way, which will assist plant breeders to find varieties that better translate increasingly unpredictable soil water supplies into food.

So next time you look upon a leaf, consider the frantic pace of dynamic calculation and adjustment of millions of little mouths, reacting as your breath falls upon them. Realise that our own fate, tied to the performance of forests and crops in future climates, hangs on the behaviour of the stomata of different species. A good reason for us to understand these unassuming little valves.

Tim Brodribb, Professor of Plant Physiology, University of Tasmania

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