A warning for wine-lovers: climate change is messing with your favourite tipple’s timing



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Record-breaking maximum temperatures are changing ripening times in Australia’s wine regions.
Shutterstock

Christopher Davies, CSIRO and Christine Bottcher, CSIRO

While the much-derided “latte set” are stereotyped as the biggest worriers about climate change, it’s the chardonnay crowd who are acutely feeling its effects.

Australia’s wine industry is both world-renowned and economically significant, with around A$5.6 billion in sales in 2016–17, and winemaking and associated tourism responsible for more than 170,000 full and part-time jobs. Statistics also show that wine consumption is now accepted as being just as dinky-di as beer drinking for the average Australian.




Read more:
A taste for terroir: the evolution of the Australian wine label


However, record-breaking daily maximum temperatures, warmer than average overnight temperatures, and increasingly erratic weather patterns are playing havoc with the way wine grapes grow and ripen. This has knock-on effects for Australian grape growers, wine producers and consumers.

Climate in the vineyard hits the cellar and the store shelf

Most of Australia’s wine regions have experienced rising average daily temperatures. One effect is changes to ripening times, which has compressed the harvesting season and given wine-makers a crucial logistical headache.

Traditionally, white grape varieties would generally reach optimum ripeness before red ones. While all grapes tend to ripen faster as temperatures rise, this effect is more pronounced for later-ripening varieties (for example Shiraz and Cabernet Sauvignon) than earlier ripening varieties (for example Chardonnay and Riesling).

Australian winegrape varieties are becoming ready for harvest simultaneously.
Shutterstock

The old process of staggered harvesting times for red and white grape varieties was efficient, allowing the winery’s capacity to be used in sequence for different varieties. Now that different varieties are ripening at the same time, vineyards and wineries will have to make tough choices about which grapes to prioritise, and which ones to leave until later, resulting in inferior wine. Alternatively, they could take the expensive decision to increase production capacity by investing in more infrastructure such as fermenters and stainless steel tanks.




Read more:
Message in a bottle: the wine industry gives farmers a taste of what to expect from climate change


Perhaps you’re thinking that you, the savvy wine drinker, are unaffected by the difficulties faced by winemakers in the vineyards and wineries far away. Unfortunately this isn’t so. Harvesting grapes when they are not at optimal ripeness to solve the logistical problems of processing can lead to lower-value wine.

The fact is that this new reality is costing everyone – grape-growers, winemakers and consumers alike.

And just in case you think that the simple answer is changing Australia’s cultured palates back to beer, think again. Hop production is being hit just as hard by climate change.

Help is at hand

Fortunately, these are problems we hope to tackle. CSIRO recently announced a five-year research partnership with Wine Australia, and one of the projects aims to adjust wine grape ripening to suit a changing climate.

We hope to do it by studying plant growth regulators (PGRs) – molecules that are used by the plant to control and coordinate development. We are using a class of PGRs called auxins, first studied in grass seedlings by Charles Darwin in the 1880s, that have important roles in vine growth, and the timing of grape growth and ripening.

Plant growth regulators can help control ripening times.
Shutterstock

By spraying these compounds onto vines and grapes shortly before ripening, auxins can potentially be used to influence the timing of this process and therefore harvest date. They are already used in other horticultural crops, such as to control fruit drop in apples and pears.

Applying very small amounts of auxin can delay grape ripening, and therefore harvest timing, by up to four weeks (Davies et al., 2015, J Ag Food Chem 63: 2137-2144). This treatment works for red and white varieties in hot or cool climates, and is safe, cheap and easy to apply.

The flavour and aroma of wines made from ripening-delayed grapes is largely indistinguishable from wines made from untreated fruit harvested at the same sugar level, up to a month earlier. An exciting exception is that, in Shiraz, auxin-induced ripening delay can be used to increase the concentration of rotundone, the compound responsible for this variety’s popular peppery notes.




Read more:
State of the Climate 2018: Bureau of Meteorology and CSIRO


Work is currently under way to fine-tune spray formulations and application times. The aim is to release a commercially available product within the next five years.

This kind of solution will be vital for the sustainable, economical production of high-quality wines from existing grape varieties in established wine growing regions. We hope it will ensure you can enjoy your favourite drop for many years to come.The Conversation

Christopher Davies, Team Leader, CSIRO and Christine Bottcher, Research scientist, CSIRO

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

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Early sowing can help save Australia’s wheat from climate change



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Timing is of the essence when it comes to growing wheat.
Author provided

James Hunt, La Trobe University

Climate change has already reduced yields for Australian wheat growers, thanks to increasingly unreliable rains and hostile temperatures. But our new research offers farmers a way to adapt.

By sowing much earlier than they currently do, wheat growers can potentially increase yields again. However, our study published today in Nature Climate Change shows that to do this they need new varieties that allow them more leeway to vary their sowing dates in the face of increasingly erratic rainfall.




Read more:
Changing climate has stalled Australian wheat yields: study


Sowing wheat is a matter of delicate timing. Seeds of current varieties need to be planted at just such a time so that, months later, the plants flower during a window of just 1-2 weeks, known as the optimal flowering period.

In Australia’s wheat belt this window is generally in early spring. At this time the soil is moist after the cool, wet winter; days are getting longer and sunnier; maximum temperatures are still relatively low; and frosts are less frequent. If crops flower outside the optimal window, yields decline sharply.

Crops and colonies

When Europeans first started trying to grow wheat in Australia, they used varieties that were suited to the cool, wet climate of northern Europe, where the optimal flowering period is in summer. These varieties were much too slow to flower in Australian conditions, and yields were very low. Wheat breeder William Farrer used faster-developing wheats from India to create the Federation variety, which revolutionised wheat production in Australia, earning Farrer the ultimate honour of having a pub named after him.

Federation wheat is a “spring wheat”, moving rapidly through its life cycle regardless of when it is planted. If you sow it earlier, it flowers earlier. For more than a century Australian wheat breeders have bred spring wheats, allowing growers to adjust their sowing time to get their crops to flower during the optimal period. Anzac Day has traditionally been the start of sowing season, after autumn rains have wet the soil enough for seeds to germinate.

Here is where climate change is causing a problem. If farmers sow later than mid-May, the wheat is likely to miss its spring flowering window. But southern Australia has experienced declining April and May rainfall, making it harder for growers to sow and establish crops at the right time. This in turn means crops flower too late the following spring, meaning yields are reduced by drought and heat.

Growers could start sowing earlier, and use stored soil water from summer rain (which hasn’t declined and has even increased at some locations), but current spring wheat varieties would flower too early to yield well. For farmers to sow earlier, they need a different sort of wheat in which development is slowed down by an environmental cue. One such environmental cue is called vernalisation. Plants that are sensitive to vernalisation will not flower until they have experienced a period of cold temperatures. These strains are thus called “winter wheats”.

Ironically enough, the wheat varieties that Europeans first brought to Australia were winter wheats, but they were further slowed by sensitivity to day length which made them too slow to reach the earlier flowering times needed in the hotter, drier colony.

But this problem can be sidestepped by using a “fast winter wheat”, which is sensitive to vernalisation but not to day length. Our previous research showed that this type of wheat was very suited to Australian conditions – it can be sown early but still flower at the right time. In fact, the vernalisation requirement means that this wheat can be sown over a much broader range of dates and experience fluctuating temperatures, and still flower at the right time.

Yielding results

In our new research, we developed different lines of wheat that varied in their response to vernalisation and day length, and grew them across the wheat belt to compare which ones would yield best at earlier sowing times.

We found that a fast winter wheat performed best over most of the wheatbelt, and on average yielded 10% more than spring wheat when they flower at the same time.

We then used computer simulations to investigate how these crops would perform at the scale of an entire farm. Our results showed that if Australian growers had access to adapted winter varieties in addition to spring varieties, they could start sowing earlier in seasons where there was an opportunity. If the rains come early, farmers can use the winter wheat; if they come late they can switch to the spring wheat, which yields better than winter wheat at late sowing times.

This would mean that more area of crop would be planted on time, and yields would increase as a result. If realised, this could increase national wheat production by about 20%, or roughly 7.1 million tonnes.




Read more:
Australia’s farming future: can our wheat keep feeding the world?


The main hurdle is that growers do not currently have access to suitable winter wheats. Breeding companies have started work on them, but it will be several years before suitably high-quality varieties become available.

Australian growers urgently need to keep pace with climate change. Although Australia only produces 4% of the world’s wheat, it accounts for 10% of exports and is thus important in determining global supply and price. If global wheat supply is low, prices rise, and it becomes unaffordable for many of the world’s poorest people, potentially causing malnutrition and civil unrest. Steeply rising wheat prices were among the factors behind the food riots that broke out in more than 40 countries in 2007-08, which helped to trigger the Arab Spring uprisings of 2010-12.

The world’s poorest people deserve to be able to buy wheat. But Australian wheat farmers also need to earn a decent living and stay internationally competitive. The only way to meet all these needs is to keep production costs low – and increasing yields by sowing the right wheat cultivars for Australia’s changing climate is one way to go about it.The Conversation

James Hunt, Associate Professor, La Trobe University

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

Why is everyone talking about natural sequence farming?


Ian Rutherfurd, University of Melbourne

On the eve of the recent National Drought Summit, prime minister Scott Morrison and deputy prime minister Michael McCormack visited Mulloon Creek near Canberra, shown recently on the ABC’s Australian Story. They were there to see a creek that was still flowing, and green with vegetation, despite seven months of drought.

Mulloon Creek was the legacy of a long collaboration between prominent agriculturalist Peter Andrews, and Tony Coote, the owner of the property who died in August. For decades they have implemented Andrews’ “natural sequence farming” system at Mulloon Creek.




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Central to the system is slowing flow in the creek with “leaky weirs”. These force water back into the bed and banks of the creek, which rehydrates the floodplain. This rehydrated floodplain is then said to be more productive and sustainable.

McCormack, who is also the minister for infrastructure, transport and regional development, was impressed and declared the success of Mulloon as a “model for everyone … this needs to be replicated right around our nation”. The ABC program suggested this form of farming could reduce the impact of drought across Australia. So, what is the evidence?

The promise of natural sequence farming

There are plenty of anecdotes but little published science around the effectiveness of natural sequence farming. What there is describes some modest floodplain rehydration, little change to stream flows, some trapping of sediment and some improvements in soil condition. These results are encouraging but not miraculous.

How much each of the different components of natural sequence farming contributes is not always clear, and the economic arguments for widespread adoption are modest. At present, there is not the standard of evidence to support this farming method as a panacea for drought relief, as proposed by the deputy prime minister.




Read more:
Helping farmers in distress doesn’t help them be the best: the drought relief dilemma


But if the evidence does emerge, why wouldn’t farmers simply adopt the methods as part of a sensible business model? Don’t all farmers want to do better in drought?

In the ABC show, and elsewhere, supporters of natural sequence farming argue that it is hard for farmers to adopt the methods because government regulations restrict use of willows, blackberries and other weeds, that they claim, are particularly effective in restoring streams.

Governments are correct to be wary of this call to use weeds, and some research suggests that native plants can do a similar job. This restriction on use of weeds might be galling for proponents of natural sequence farming but it should not be a fundamental impediment to adoption.

A more important frustration for natural sequence farming practitioners is how widely the approach can be applied. In Australian Story, John Ryan, a rural journalist, says:

I am sick of politicians, farmers groups, and government departments telling me that Peter Andrews only works where you’ve got little creeks in a mountain valley … I’ve seen it work on flat-lands, steep lands, anywhere.

Natural sequence farming arose in the attempt to restore upland valleys and creeks in southern NSW that were once environmentally valuable chains of ponds or swampy meadows. But these waterways have become deeply incised, degraded, and disconnected from their floodplains. Not only does this incision produce a great deal of sediment pollution, but it produces many agricultural problems.




Read more:
Spring is coming, and there’s little drought relief in sight


In reality, small and medium-sized stream systems across much of Australia have deepened after European settlement. If the leaky weirs of natural sequence farming are effective, then they could be applied across many gullied and incised streams across the country.

We’ve already been doing it

The good news is that landholders and governments have already been using aspects of natural sequence farming in those very gullies for decades to control erosion.

Since the 1970s, across the world, one useful method for controlling erosion has been grade-control structures. They were once made of concrete but are now usually made of dumped rock (called rock-chutes), and also logs.

Rock chutes in Barwidgee Creek, 1992, Ovens River catchment, Victoria. Source: T McCormack NE Catchment Management Authority.
T McCormack NE Catchment Management Authority
The same creek in 2002. It is now heavily vegetated and has pools of water, just like Mulloon Park.
T McCormack NE Catchment Management Authority

These structures reduce the speed of water flow, trap sediment, encourage vegetation, and stop gullies from deepening. These are all goals of natural sequence farming using leaky weirs.

There are thousands of such structures, supported by government initiatives, across the Australian landscape acting as an unrecognised experiment in rehydration and drought protection.




Read more:
We must strengthen, not weaken, environmental protections during drought – or face irreversible loss


Perhaps governments should already have evaluated these structures, but the rehydration potential of these works has not been recognised in the past. It is time that this public investment was scientifically evaluated.

We may find that natural sequence farming and the routine government construction of grade-control structures have similar effects on farmland and the environment.

But whatever the outcome, gully management is not likely to mark the end of drought in the Australian landscape.The Conversation

Ian Rutherfurd, Associate Professor in Geography, University of Melbourne

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

Farmers’ climate denial begins to wane as reality bites


Sarah Ann Wheeler, University of Adelaide and Céline Nauges, Inra

Australia has been described as the “front line of the battle for climate change adaptation”, and our farmers are the ones who have to lead the charge. Farmers will have to cope, among other pressures, with longer droughts, more erratic rainfall, higher temperatures, and changes to the timing of seasons.

Yet, puzzlingly enough to many commentators, climate denial has been widespread among farmers and in the ranks of the National Party, which purports to represent their interests.




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The Nationals have changed their leader but kept the same climate story


Back in 2008, only one-third of farmers accepted the science of climate change. Our 2010-11 survey of 946 irrigators in the southern Murray-Darling Basin (published in 2013) found similar results: 32% accepted that climate change posed a risk to their region; half disagreed; and 18% did not know.

These numbers have consistently trailed behind the wider public, a clear majority of whom have consistently accepted the science. More Australians in 2018 accepted the reality of climate change than at almost any time, with 76% accepting climate change is occurring, 11% not believing in it and 13% being unsure.

Yet there are signs we may be on the brink of a wholesale shift in farmers’ attitudes towards climate change. For example, we have seen the creation of Young Carbon Farmers, Farmers for Climate Action, the first ever rally on climate change by farmers in Canberra, and national adverts by farmers on the need for climate action. Since 2016 the National Farmers Federation has strengthened its calls for action to reduce greenhouse emissions.

Our latest preliminary research results have also revealed evidence of this change. We surveyed 1,000 irrigators in 2015-16 in the southern Murray-Darling Basin, and found attitudes have shifted significantly since the 2010 survey.

Now, 43% of farmers accept climate change poses a risk to their region, compared with just 32% five years earlier. Those not accepting correspondingly fell to 36%, while the percentage who did not know slightly increased to 21%.

Why would farmers deny the science?

There are many factors that influence a person’s denial of climate change, with gender, race, education and age all playing a part. While this partly explains the attitudes that persist among farmers (who tend to be predominantly male, older, Caucasian, and have less formal education), it is not the full story.

The very fact that farmers are on the front line of climate change also drives their climate change denial. For a farmer, accepting the science means facing up to the prospect of a harsher, more uncertain future.

Yet as these changes move from future prospect to current reality, they can also have a galvanising effect. Our survey results suggest farmers who have seen their farm’s productivity decrease over time are more likely to accept the science of climate change.

Many farmers who have turned to regenerative, organic or biodynamic agriculture talk about the change of mindset they went through as they realised they could no longer manage a drying landscape without major changes to their farming practices.




Read more:
Farmers experiencing drought-related stress need targeted support


In addition, we have found another characteristic that is associated with climate change denial is whether farmers have identified a successor for their farm. Many farmers desire to turn their farm over to the next generation, hopefully in a better state than how they received the farm. This is where the psychological aspect of increased future uncertainty plays an important role – farmers don’t want to believe their children will face a worse future on the farm.

We all want our children to have better lives than our own, and for farmers in particular, accepting climate change makes that very challenging. But it can also prompt stronger advocacy for doing something about it before it’s too late.

What can we do?

Whether farmers do or do not accept climate change, they all have to deal with the uncertainty of weather – and indeed they have been doing so for a very long time. The question is, can we help them to do it better? Given the term “climate change” can be polarising, explicit climate information campaigns will not necessarily deliver the desired results.




Read more:
To help drought-affected farmers, we need to support them in good times as well as bad


What farmers need are policies to help them manage risk and improve their decision-making. This can be done by focusing on how adaptation to weather variability can increase profitability and strengthen the farm’s long-term viability.

Farming policy should be more strategic and forward-thinking; subsidies should be removed for unsustainable practices; and farmers should be rewarded for good land management – both before and during droughts. The quest remains to minimise the pain suffered by all in times of drought.The Conversation

Sarah Ann Wheeler, Professor in Water Economics, University of Adelaide and Céline Nauges, Research Director, Inra

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

Giving environmental water to drought-stricken farmers sounds straightforward, but it’s a bad idea


Erin O’Donnell, University of Melbourne and Avril Horne, University of Melbourne

Deputy Prime Minister Michael McCormack last week suggested the government would look at changing the law to allow water to be taken from the environment and given to farmers struggling with the drought.

This is a bad idea for several reasons. First, the environment needs water in dry years as well as wet ones. Second, unilaterally intervening in the way water is distributed between users undermines the water market, which is now worth billions of dollars. And, third, in dry years the environment gets a smaller allocation too, so there simply isn’t enough water to make this worthwhile.




Read more:
To help drought-affected farmers, we need to support them in good times as well as bad


In fact, the growing political pressure being put on environmental water holders to sell their water to farmers is exactly the kind of interference that bodies such as the Commonwealth Environmental Water Holder were established to avoid.

The environment always needs water

The ongoing sustainable use of rivers is based on key ecosystem functions being maintained, and this means that environmental water is needed in both wet and dry years. The objectives of environmental watering change from providing larger wetland inundation events in wet years, to maintaining critical refuges and basic ecosystem functions in dry years.

Prolonged dry periods cause severe stress to ecosystems, such as during the Millennium Drought when many Murray River red gums were sickened by salinity and lack of water. Environmental water is essential for ecosystem survival during these periods.

Under existing rules, environmental water holders can sell and buy water so as to deliver maximum benefits at the places and times it is most needed.

But during dry years the environmental water holders receive the same water allocations as other users. So it’s very unlikely there will be any “spare” water during drought. During a dry period, the environment is in urgent need of water to protect endangered species and maintain basic ecosystem functions.

We should be cautious when environmental water is sold during drought, as this compromises the ability of environmental water holders to meet their objectives of safeguarding river health. When the funds from the sale are not used to mitigate the loss of the available water to the environment, this is even more risky.

Secure water rights support all water users

In response to McCormack’s suggestion, the National Irrigators’ Council argued that compulsorily acquiring water from the environment can actually hurt farmers who depend on the water market as a source of income or water during drought.

Water markets are underpinned by clear legal rights to water. In other words, the entitlements the environment holds are the same as those held by irrigators. If the government starts treating environmental water rights as barely worth the paper they’re printed on, farmers would have every reason to fear that their own water rights might similarly be stripped away in the future.

Maintaining the integrity of the water market is important for all participants who have chosen to sell water, based on reasonable expectations of how prices will hold up.

Can taking environmental water actually help farmers?

As federal Water Resources Minister David Littleproud noted this week, environmental water is only about 8% of total water allocations in storage throughout the Murray Darling Basin. In the southern basin, it is still only about 14%. This means that between 86% and 92% of water currently sitting in storage is already allocated to human use, including farming.

There are calls for the Commonwealth government to treat the drought as an emergency and to take (or “borrow”) water from environmental water holders. But the Murray-Darling Basin Plan already has specific arrangements in place for emergencies in which critical human water needs are threatened.

The current situation in New South Wales is not an emergency under the plan. Water resources across the northern Murray-Darling Basin are indeed low, but storages in the southern basin are still 50-75% full. Although many licence holders in NSW received zero water in July’s round of allocations, high-security water licences are at 95-100%. In northern Victoria, most high-reliability water shares on the Murray are at 71% allocation.

The situation can therefore be managed using existing tools, such as providing direct financial support to farming communities and buying water on the water market.

Environmental water is an investment, not a luxury

As Australia’s First Nations have known for millennia, a healthy environment is not an optional extra. It underpins the sustainability and security of the water we depend on. When river flows decline, the water becomes too toxic to use.




Read more:
Spring is coming, and there’s little drought relief in sight


Water has been allocated to the environment throughout the Murray-Darling Basin to prevent the catastrophic blue-green algal blooms and salinity problems we have experienced in the past. If we want safe, secure water supplies for people, livestock and crops, we need to keep these key river ecosystems alive and well during the drought.

In the past decade alone, Australia has spent A$13 billion of taxpayers’ money to bring water use in the Murray-Darling Basin back to sustainable levels. If we let our governments treat the environment like a “water bank” to spend when times get tough, this huge investment will have been wasted.The Conversation

Erin O’Donnell, Senior Fellow, Centre for Resources, Energy and Environment Law, University of Melbourne and Avril Horne, Research fellow, Department of Infrastructure Engineering, University of Melbourne

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

Climate change will reshape the world’s agricultural trade



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Australia’s grain exports will suffer under climate change.
Alpha/Flickr, CC BY-NC

Luciana Porfirio, CSIRO; David Newth, CSIRO, and John Finnigan, CSIRO

Ending world hunger is a central aspiration of modern society. To address this challenge – along with expanding agricultural land and intensifying crop yields – we rely on global agricultural trade to meet the nutritional demands of a growing world population.




Read more:
How many people can Australia feed?


But standing in the way of this aspiration is human-induced climate change. It will continue to affect the issue of where in the world crops can be grown and, therefore, food supply and global markets.

In a paper published today in Nature Palgrave, we show that climate change will affect global markets by reshaping agricultural trading patterns.

Some regions may not be able to battle climate impacts on agriculture, in which case production of key commodities will decline or shift to new regions.

The challenge

The negative impacts of climate change on agricultural production are of great concern to farmers and decision-makers. The concern is increasingly shared by governments including those most hostile to the advancement of climate change mitigation.

Even the United States, which has opted out of the Paris Agreement, acknowledged at last year’s G7 summit that climate change was one of a number of threats to “our capacity to feed a growing population and need[ed] to be taken into serious consideration”.

The UN median population projection suggests that the world population will reach some 10 billion in 2050. Between 2000 and 2010, roughly 66% of the daily energy intake per person, about 7,322 kilojoules, was derived from four key commodities: wheat, rice, coarse grains and oilseeds. However, the most recent UN report on food security and nutrition shows that world hunger is on the rise again and scientists believe this is due to climate change.




Read more:
World hunger is increasing thanks to wars and climate change


We must ask: what is the cost of adapting to climate change versus the cost of mitigating carbon emissions? And assuming that changes in climate and crop yields are here to stay, are we prepared for permanent agricultural shifts?

Disruptions and opportunities

Agricultural production is significantly affected by climate change. Our results suggest that global trade patterns of agricultural commodities may be significantly different from today’s reality – with or without carbon mitigation. This is because climate change and the implementation of a carbon mitigation policy have different effects on a regions’ agricultural production and economy.

Take the US, which in 2015 had 30% of the global market share of coarse grains, paddy rice, soybeans and wheat. We modelled production between 2050-59 under two scenarios: in a world 2℃ average temperature rise, and with a 1.5℃ increase. In both cases, the US market share would shrink to about 10%.




Read more:
As global food demand rises, climate change is hitting our staple crops


China is currently a net importer of these commodities. If temperature increases by 1.5℃, we expect to see an increase in exports of some products, like rice to the rest of Asia.

(However, it’s worth bearing in mind that limiting warming would be very expensive for China, as it would need to absorb a costly technological transition to a low carbon economy.)

China’s story is different in the 2℃ scenario. Our projections suggest that climate change will make China, as well as other regions in Asia, more suitable to produce different commodities.

China’s economy will keep expanding, whilst the new climatic conditions create opportunities to produce other food commodities at a greater scale and export to new regions.

Our results also suggest that, regardless of the carbon policy scenarios, Sub-Saharan Africa will become the greatest importer of coarse grains, rice, soybeans and wheat by 2050. This significant change in Sub-Saharan Africa imports is driven by the fact that the largest increase in human population by 2050 will occur in this region, with a significant increase in food demand.

In our research Australia was aggregated in “Oceania” with New Zealand. The exports from Oceania to the rest of the world comprised about 1.6% of the total in 2015, which is dominated by wheat exports from Australia.

Our projections suggest that carbon mitigation policies would favour the wheat industry in this region. The opposite occurs without carbon mitigation: the production and exports of wheat are projected to decline due to climate change impacts on agriculture.

The benefits of mitigation

A recent report published by the European Commission about the challenges of global agriculture in a climate change context by 2050 highlights that

…emission mitigation measures (i.e. carbon pricing) have a negative impact on primary agricultural production […] across all models.

However, the report does not mention the technological costs to buffer (or adapt to) the effect of climate change on agriculture.

Our results suggest that the cost paid by the agricultural sector to reduce carbon dioxide emissions is offset by the higher food prices projected in the non-mitigation scenario, where agricultural production is significantly affected by climate change. We found that there is a net economic benefit in transitioning to a low carbon economy. This is because agricultural systems are more productive under the mitigation scenario, and able to meet the demand for food imposed by a growing population.




Read more:
Australian farmers are adapting to climate change


Mitigating CO₂ emissions has the side benefit of creating a more stable agricultural trade system that may be better able to reduce food insecurity and increase welfare.

Changes in the agricultural system due to climate are inevitable. It is time to create a sense of urgency about our agricultural vulnerabilities to climate change, and begin seriously minimising risk.The Conversation

Luciana Porfirio, Research Scientist, Agriculture & Food, CSIRO | Visiting fellow at the Fenner School of Enviroment & Society, CSIRO; David Newth, Team Leader, Australian And Global Carbon Assessments, CSIRO, and John Finnigan, Leader, Complex Systems Science, CSIRO

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

The secret agents protecting our crops and gardens


File 20180420 75104 1u2pbpt.jpg?ixlib=rb 1.1
Lacewings are fantastic predators and are easy to rear and release.
Dan Papacek & Tony Meredith (Bugs for Bugs), Author provided

Lizzy Lowe, Macquarie University and Manu Saunders, University of New England

Insect pests cause a huge amount of damage to crops globally. In Australia alone, pests are responsible for around A$360 million of crop losses a year. Controlling pest outbreaks is crucial for food security and human health. Since the 1940s, our primary defence against crop pests has been synthetic pesticides. But using pesticides comes at a huge cost.

Not all bugs are bad!

Bees, flies and butterflies help to pollinate our plants. Decomposers like beetles and worms help break down wastes and return nutrients to the soil. Meanwhile, predators and parasites help control the species that are pests. One of the biggest environmental problems with pesticides is that they can affect these beneficial species as well as the pests they’re targeting.

Predatory insects and spiders control pests with none of the health and environmental risks of chemicals. So when we kill these species with insecticides, we are shooting ourselves in the foot.




Read more:
The real cost of pesticides in Australia’s food boom


Losing insects also has flow-on effects for larger animals that rely on them for food. Because invertebrates have such important roles to play in our environment, losing them to insecticides can completely change how ecosystems function.

An alternative to insecticides

Biological control (or biocontrol) relies on “secret agents” – the natural enemies (predators and parasitoids) of pests that live freely in the ecosystems around us.

There is a huge range of predatory invertebrates that eat pests. They include dragonflies, preying mantids, beetles (including ladybugs), lacewings, spiders, mites, wasps, and even some flies.

Parasitoids, meanwhile, are insects that lay their eggs in the bodies of other invertebrates. Their larvae extract nutrients from the host during their development, which ultimately kills the host. Wasps are best known for this strategy but there are also parasitoid flies and beetles.

Lady birds are voracious predators ready to eat pests in crops and gardens.
Manu Saunders

Predators and parasitoids are useful because they use pest insects, like caterpillars and aphids, as food to reproduce and grow their populations. We walk past many of these hard working agents every day without knowing it.

One biocontrol method that gardeners and land managers use is called augmentation. This simply means raising lots of live individuals of particular natural enemies, like ladybirds or wasps, and releasing them into an area to control pests.

Alternatively, gardeners might change the local environment to encourage these natural enemies to move in on their own. They might include natural insectariums or planting different types of vegetation to encourage diverse invertebrate communities. There is increasing evidence of the success of these strategies in organic farming so we should be thinking about using them more broadly.

Selecting your insects

If you want to release biocontrol agents, you need to choose them carefully, just like human special agents. Like any introduced plant or animal, there is a risk that good bugs could become pests (if they feed on the wrong insects, for example).

Selecting biological control agents requires close collaboration between managers, skilled entomologists and other scientists. For each new species, they identify the pest and some potential predators. They look at the predator’s life cycle and resource needs, and consider how it interacts not just with pests, but with other insects too. If agents are coming in from overseas, they also need to be cleared by government biosecurity.

Parasiotid wasps, lacewings, predatory mites, ladybird beetles, and nematodes are all common biocontrol agents. These species are relatively easy to raise in large numbers and work well when released into the field. Spiders are also a really important predator of many pest insects, but they’re often overlooked in the biocontrol game because they are harder to breed – and for some reason people don’t always like releasing large numbers of spiders.

Many biocontrol agents are enemies of pests in general, preying on aphids, caterpillars and fruit flies alike. It’s important to have generalists around for every day pest control, but sometimes a more targeted approach is needed. This is when specialised predators or parasitoids come in. These are species that only target specific pests like leaf miners, beetles, scale insects or spider mites. This way the target pest can be managed with no risk of the parasitoids accidentally attacking other beneficial invertebrates.

Raising good bugs

It’s very exciting to get live insects in the mail!
Lizzy Lowe

Once a biocontrol agent has been selected, greenhouses or lab facilities start raising a large population. This is an emerging market in Australia, but there are already a number of companies in Australia who specialise in rearing biological control agents.

This is a tricky job because demand for the product is variable and is not easy to predict. Warmer seasons are the peak time for most pests, but problems can arise at any time of the year. In most cases the biocontrol company will maintain breeding colonies throughout the year and will be ready to ramp up production at a moment’s notice when a farmer identifies a pest problem. Each company usually provides 10-20 different biocontrol agents and are always looking for new species that might be useful.




Read more:
Birds, bees and bugs: your garden is an ecosystem, and it needs looking after


When it comes to getting the agents to the farmers, the bugs can be shipped as eggs (ready to hatch on arrival), or as live adults ready to disperse and lay their own eggs. The packages are express posted in boxes designed to keep the insects cool and safe.

Once the farmer or natural resource manager receives the bugs, applying them is quite simple. The secret agents are released among the crops, usually by hand, but in some special cases they may be airlifted in via specialised drones!

Drones can be used to deploy biological control agents.
Nathan Roy (Aerobugs)

It’s important to monitor the pests and the biological control agents after release to check that the agents are working. Some farmers are happy to do this themselves but most biological control companies have experts to visit the farms and keep an eye on all parties.

Can I use good bugs in my garden?

The ConversationIf you have a problem with a pest like aphids it is possible to buy predators such as ladybirds or lacewings to quickly deal with the problem. But for long term pest control, there are probably already some natural enemies living in your garden! The easiest and cheapest way to help them is to put the insecticides away and ensure your garden is a friendly environment for secret agents.

Lizzy Lowe, Postdoctoral researcher, Macquarie University and Manu Saunders, Research fellow, University of New England

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