How invasive weeds can make wildfires hotter and more frequent

Mixed grill: burning combinations of invasive and native plants helps us understand how invasive plants make fires hotter and more likely.
Sarah Wyse, CC BY-ND

Tim Curran, Lincoln University, New Zealand; George Perry, and Sarah Wyse

Over the past year the global media has been full of reports of catastrophic fires in California, the Mediterranean, Chile and elsewhere. One suggested reason for increases in catastrophic wildfires has been human-induced climate change. Higher temperatures, drier weather and windier conditions all increase the impact of fires.

While climate change indeed raises the risk of wildfires, our research shows that another way humans can change patterns of fire activity is by introducing flammable plants to new environments.

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Read more: How will Canada manage its wildfires in the future?

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Plantations of highly flammable exotic species, such as pines and eucalypts, probably helped to fuel the recent catastrophic fires in Portugal and in Chile. In arid regions, such as parts of the US southwest, the introduction of exotic grasses has transformed shrublands, as fires increase in severity.

Invasive plants and fire

How do invasive plants change fire patterns? We burned species mixtures (aka “mixed grills”) on our plant barbecue to help find out.

Invasive plants are responsible for changing the patterns of fire activity in many ecosystems around the world. In particular, invasive species can lead to hotter and more frequent fires.

Invasive plants can also reduce fire frequency and fire intensity, but there are fewer examples of this occurring worldwide.

One of the main ways flammable invasive plants can have long-lasting impacts on an ecosystem comes from positive fire-vegetation feedbacks. Such feedbacks can occur when a flammable weed invades a less fire-prone ecosystem. By changing the available fuel the invader makes fires more likely and often hotter.

If the invading species has characteristics that allow it to outcompete native species after a fire, then it will further dominate the ecosystem. Such traits include thick bark, the ability to resprout following fire, or seeds that survive burning. This invasion will likely lead to more fires, changing the species composition and function of the ecosystem in a “fire begets fire” cycle. Extreme examples of this dynamic are where flammable grasses or shrubs invade forests, leading to loss of the forest ecosystems.

Mixed grills

We wanted to understand how invasive plants interact with other species when burned in combination. To explore the mechanisms underpinning such feedbacks, we examined how invasive plants might change the nature of a fire when burned together with native species.

We collected 70cm shoots of four globally invasive species (of both high and low flammability) and burned them in pairwise combinations with New Zealand native trees and shrubs to determine which characteristics of a fire could be attributed to the invasive plants.

Samples of Hakea sericea (foreground) and Kunzea robusta (rear) arranged on the grill of our plant barbecue.
Sarah Wyse, CC BY-ND

We found that overall flammability was largely driven by the most flammable species in the mixture, showing how highly flammable weeds could set in motion fire-vegetation feedbacks.

We established that a greater difference in flammability between the two species led to a larger influence of the more flammable species on overall flammability. This outcome suggests weeds that are much more flammable than the invaded community can have larger impacts on fire patterns.

Importantly, we also showed the influence of the highly flammable species was independent of its biomass, meaning highly flammable weeds may impact community flammability even at low abundances.

When we looked closer at the different components of flammability (combustibility, ignitability, consumability and sustainability) we found some important nuances in our results.

While the maximum temperature reached in our burns (combustibility) and the ignition speed (ignitability) were both most influenced by the more flammable species, consumability (the amount of biomass burned) and sustainability (how long the fire burns) were equally influenced by both the more flammable and less flammable species.

In short, more flammable weeds will cause a fire to ignite more quickly and burn hotter.

However, less flammable species can reduce the duration of a fire compared to when a more flammable species is burnt alone. These results could have important ecological implications, as the longer a fire burns the more likely it is to kill plants: low-flammability plants could reduce this impact.

Measuring how long a fire burns on our plant barbecue.
Tom Etherington, CC BY-ND

Managing weeds to reduce fire impacts

Even low abundances of highly flammable invasive weeds could set in motion positive fire-vegetation feedbacks that lead to drastic changes to ecosystems. If this result holds when our shoot-scale experiments are repeated using field trials, then land managers should work quickly to remove even small infestations of highly flammable species, such as gorse (Ulex europaeus) and prickly hakea (Hakea sericea).

Conversely, the role of low flammability plants in extinguishing fires further supports the suggestion that the strategic planting of such species across the landscape as “green firebreaks” could be a useful fire management tool.

In any case, our “mixed grill” study further highlights the role of exotic plants in fuelling hotter wildfires.

Tim Curran, Senior Lecturer in Ecology, Lincoln University, New Zealand; George Perry, Professor, School of Environment, and Sarah Wyse, Early Career Research Fellow, The Royal Botanic Gardens, Kew and Research Fellow, School of Environment

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

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The federal Climate Policy Review: a recipe for business as usual

The new climate policy review proposes loosening the rules on Australia’s biggest-emitting companies, such as power generators.
Marcella Cheng/The Conversation, CC BY

Rebecca Pearse, University of Sydney

The federal government’s newly released Climate Policy Review is hugely disappointing, but far from surprising. It does not depart from what the Turnbull government has been saying for some time: it plans to loosen compliance obligations for emissions-intensive companies even further, reintroduce international carbon offsets, and implement the planned National Energy Guarantee.

The review was first announced November 2016, when Australia ratified the Paris Climate Agreement, committing it to a 2030 emissions target of 26-28% below 2005 levels. A year later, the final report claims that Australia is on track to meet this target with its existing climate change policies.

The review indicates plans to keep the Emissions Reduction Fund, a A$2.55 billion pot of public money from which companies can bid for funding to implement emissions reductions. But it does not promise new funding beyond the existing A$2.55 billion, nor does it address ongoing problems with the scheme.

The Climate Policy Review is also not surprising because it continues a longstanding, bipartisan tradition in weak climate policy formulation. It echoes four enduring features of Australia’s ineffective climate policy since the 1990s. We can think of them as a recipe for business as usual.

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Read more: Australia’s 2030 climate target puts us in the race, but at the back

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Step 1: Pursue a weak emissions target.

Australia’s 2020 and 2030 emissions targets are modest. The 2020 target of reducing emissions by 5% below 2000 levels (a reduction equivalent to 294 million tonnes of carbon dioxide) will be met largely on the back of a loophole Australia secured way back in 1997 when the Kyoto Protocol was negotiated.

The Turnbull government ratified the Paris Agreement in 2016, having pledged to cut emissions by 26-28% below 2005 levels by 2030. The review provides no clear answer as to how the 2030 target will be met. However, there are signs that domestic emissions will continue to rise, and that international carbon offsets will have to be bought to “balance” the national carbon account.

Step 2: Loosen obligations for industry as much as possible.

Weak compliance obligations for industry are the reason why emissions may rise in the future. The review signals changes to the Safeguard Mechanism – a key plank of its existing Direct Action policy suite, which aims to encourages large businesses not to exceed their historical emissions levels.

The problem is that the Safeguard Mechanism is already weak, and only covers around 140 of Australia’s most emissions-intensive firms.

The Safeguard Mechanism requires companies to report on their emissions against an historical baseline rate. If they exceed this baseline, they can meet their obligations by buying carbon credits. The baseline is already very flexible. For instance, companies can ask for their baseline to be recalculated if their overall emissions have increased but their emissions intensity (the amount of emissions per unit of economic productivity) has improved.

The Climate Policy Review says the government plans to increase this flexibility still further, and will work with industry to change baseline calculations. It makes the bizarre argument that the problem with baselines is that they reflect the historical activity of businesses which might be emitting more today if they increase production to remain competitive.

The proposed solution? “Broaden access to baseline increases”, which could mean the government plans to rewrite baseline rules to ensure companies are not obliged to reduce their emissions if their production grows. This goes against the very grain of climate policy, which should be to encourage high-emitting companies to change how they do business.

Of course, this isn’t the first time a government has sought to be generous to emissions-intensive industries. The Keating and Howard governments made emissions reduction schemes entirely voluntary.

The Rudd and Gillard governments also invented similar loopholes to the one suggested by the new review. Both Rudd’s proposed Carbon Pollution Reduction Scheme and Gillard’s carbon pricing scheme included incredibly generous industry compensation to the most emissions-intensive industries in the form of free permits and cash payments. These were weakly justified on the basis of international competition.

Step 3: Shift the heavy lifting elsewhere.

The review signals a return to another policy tactic to avoid cutting emissions in the domestic economy. In a major departure from the Abbott government’s position, the current review embraces once again the idea of buying international carbon credits.

Carbon offsets have been a longstanding part of Australian climate policy, dating back to early reports on emissions trading in the 1990s. More recently, the Howard government’s emissions trading taskgroup and the Garnaut Reviews both argued for international offsets as a source of “flexibility”.

Carbon credits are generated from projects that propose to reduce emissions, usually in industries and places not covered by national emissions trading schemes. In Australia, they are produced mostly in the land sector under the Emissions Reduction Fund, while globally these projects have been centred on China, India, Brazil, and rainforest nations.

The idea behind these projects is that they deliver “additional” emissions reductions that would not have happened without the investment from those buying the carbon credits. In reality it’s much more complicated. Carbon offsets shift the hard work away from industries and countries that should really be working the hardest – such as Australia’s electricity sector.

By offshoring the heavy lifting, governments delay real, meaningful change in cutting emissions. Federal Environment and Energy Minister Josh Frydenberg summed up the false logic of international carbon offsetting in his recent comments:

When it comes to helping the environment, it doesn’t matter if you’ve reduced a tonne of CO₂ here in Australia or in another country.

But it does matter. Sure, carbon offsetting allows flexibility in the short term, but it makes it much harder in the long term to move away from fossil fuels if we’re not investing in renewable energy infrastructure right now.

Step 4: Act as if it’s out of the question for governments to plan and build a low-carbon economy.

The National Energy Guarantee (NEG) requires electricity retailers to buy or generate electricity at or below a particular emissions intensity. The government is fond of telling us how the policy is “technology-neutral”, replacing the Renewable Energy Target which specifically encouraged low-carbon energy investments.

The details of how the NEG will be designed are still sketchy, but it is likely to take the form of a sort of market mechanism.

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Read more: Will the National Energy Guarantee hit pause on renewables?

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Market mechanisms will do little in the absence of structural change in the failing electricity market. The history of energy infrastructure development in Australia and across the globe tells us that concerted planning and public investment is essential for energy transformations.

Meanwhile, the more recent political and practical failures of carbon pricing show that a techno-market fix will not “solve” climate politics for the current or future governments.

Rebecca Pearse, Lecturer, University of Sydney

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

Tourists are happy when taken off the beaten track, and smaller cities and towns can tap into that

Yes, it’s a beautiful part of the world, but what sets Ballyhoura apart is the deliberate focus on a warm, local welcome.
stephendotcarter/flickr, CC BY

Elizabeth Turenko, Griffith University and Karine Dupré, Griffith University

Big cities and places with internationally renowned attractions have long been the most popular tourist destinations. Even today, Chinese tour companies in Australia, for instance, mostly focus on the biggest cities – Sydney, Melbourne, Brisbane – and landmarks like Uluru. But modern tourism is starting to take a slightly different path, regional travel, which creates economic benefits for towns and also leaves tourists with a better impression of a country.

Unpublished research undertaken by one of us (Elizabeth Turenko) while working as a tour leader in Ukraine in 2013-2014 confirmed this. Feedback from guests travelling on a group tour to Europe showed 80% preferred to visit “well-known” large cities, mostly capitals, when it came to choosing a tour.

Most of the time, though, these tourists were disappointed because the cities did not live up to their expectations. But, the study revealed, 75% of tourists enjoyed travelling to smaller towns when they did decide to visit them as part of a tour.

Big cities are losing their local flavour

There is no doubt the major cities are attractive and are still perceived as the essence of a country for many tourists. Yet the question remains: are these cities actually showing the “real country”? At a time of globalisation and global cities, to what extent do the larger cities still give tourists “the taste” of local culture.

Rural Tourism Marketing Group CEO Joanna Steele writes:

In the past five years tourism has seen some big changes. Large numbers of travellers have lost interest in cookie-cutter restaurants, lodging and attractions. Instead, they want local food, local attractions and connection to the lifestyles of local people.

The best places to experience that are often small local towns and villages. Here life hasn’t yet been adapted to tourist needs and the authenticity feels right.

Turenko also investigated the tourists’ preferences during a group bus tour in Europe. The main program involved a one-day visit to Amsterdam and a second day on which tourists could spend their free time in Amsterdam or go on a group trip to Volendam, a small town 20km away. The 90% of the group who opted for the town visit were very satisfied with their decision.

So, was there anything special about Volendam? Not really.

Much like many small towns in the Netherlands, Volendam has limited tourist attractions, these being mostly its built heritage (wooden buildings) and cultural assets (a museum and a cheese factory). When surveyed, the visitors explained they enjoyed the glimpse into the local culture and the routine life of the locals.

The tourists appreciated going to local shops and eating at local restaurants far away from standardised brands and international franchises. They felt they could feel the “soul” of the country.

What does Volendam have that Amsterdam doesn’t? It probably comes down to everyday local character.

At the time of this 2014 survey, cities and holidays at the coast were the main attractions for visitors to the Netherlands (36% and 22%, respectively). But interest in the countryside and touring the Netherlands (12% and 10%, respectively) has been increasing.

Finding a local tourism niche

Let’s be frank: smaller towns and villages have not been dormant, and many have jumped at the opportunities offered by tourism. We all have heard about farm holidays, horse riding, wine tasting tours, nature guided walks and so on.

Building on this, innovative regional tourism practices have been recognised worldwide for displaying a breadth of approaches and end products. A good example in Ireland is Ballyhoura, “a world where the little pleasures of sharing everyday things with the locals in Ballyhoura – talking with them, walking with them and sharing a joke – is possibly the greatest attraction of them all!”

Despite a lack of outstanding tourism resources, the area became a successful tourism destination thanks to a very personalised marketing method. Visitors even received a welcoming letter. The focus on “promoting a genuine rural experience and warm welcome” creates an incentive for more local start-up enterprises and for a co-operative, closing-the-loop process of quality control.

Longreach and Winton are Australian towns that have taken advantage of distinctive local histories and features such as old mines and fossil beds. Longreach has the Australian Stockman’s Hall of Fame and the Qantas Founders Museum, while Winton’s Australian Age of Dinosaurs Museum offers “products” of the natural environment such as dinosaur stamps and bones.

Nowhere else has one: the Stockman’s Hall of Fame in Longreach, Queensland.
James Shrimpton/AAP

Yet all attempts have not been met with success. Many smaller towns are slowly disappearing in Australia. Main streets with closed shops and abandoned business are not uncommon.

The combination of lack of employment and population ageing and loss is a chicken-and-egg situation. The various levels of government are acutely aware of this, and tourism offers a possible way out of the dilemma facing these towns. Several recent initiatives have shown how tourism can contribute to the development of these areas when innovation, expertise and community participation are brought together.

Charleville in far west Queensland offers a great example of this, with the outback town working on making the most of its clear nighttime skies, far from the city lights. An extension to the Cosmos Centre and Observatory, funded by state and local governments, has boosted visitor numbers in just one year. The extension displays fun and serious facts about planets and life in space, enhanced by interactive media.

For the town of fewer than 4,000 people, the growth in tourism is like a nice spring rain after a long dry season. It’s another reminder of why rural tourism can be “the perfect small town business idea”.

Elizabeth Turenko, PhD Candidate, Griffith University and Karine Dupré, Associate Professor in Architecture, Griffith University

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

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