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In 40 years, The Intergenerational Report predicts Australia's population may hit nearly 40 million.
More mouths to feed means we'll need to produce or import more food.
But agricultural advances have meant an increasing use of synthetic pesticides and fertilisers.
Some people believe these negatively affect health.
Could organic food be the answer? Signe Dean investigates.
Agriculture is one of the cornerstones of human evolution.
Over the past couple centuries, new technology has led to new farming practices.
But along with them have arrived environmental problems, such as pollution.
Organic farming tries to counter this trend.
Instead of using synthetic fertilisers and pesticides, it relies on more basic methods, such as the use of compost and manure.
Organic farmer Adam Willson is the chair of Organic Federation of Australia.
He explains that organic farmers pay special attention to the health of the soil.
To Willson, one of the core practices is remineralisation.
"Get the minerals back into the soil, and the example would be - a mountain breaks down, all the minerals run down the river, and then when it floods it goes out to the soils to the sides of the river and as we've spread agriculture away from the river and we're now in all sorts of different places, it's very important to get the minerals back out there into the soil."
Organic farming is practiced in several ways, but they all have something in common.
University of New England Soil Scientist Dr Nellie Hobley explains organic farming's key difference.
"I think the principles of organic farming are basically that you want to recycle as much as possible, and that the inputs that you have into your systems should come from natural sources, whereas in, I guess, what you'd call conventional farming, the inputs don't have to be derived from natural sources."
Mass agricultural production that uses synthetic chemicals is what we sometimes call 'conventional farming'.
To make sure organic farmers work correctly, there are certification systems in place.
Mr Willson explains how Australian organic farming is regulated.
"The real key thing here in Australia is that we have six certifiers that certify to the national standards. And if you look at it carefully, what happens is that a farmer who has a farm, they sign off on a statutory dec on the first day that they decide to become a farmer, and then 3 years later they're fully certified depending on the history of the farm. Now, every year they get an audit, and in the first year they get two. And, in addition to that, five per cent of all organic farmers get random audits. So, they just turn up and they say 'oh we're just come to check that you're doing the right job.' "
For the past two decades organic food has been on the rise.
According to the Research Institute of Organic Agriculture, in 2014 worldwide a little over 43 million hectares were farmed organically.
In fact, Australia has the most land dedicated to organic farming: 17-point-2 million hectares.
Consumers buy organic food because they think it is more healthy and nutritious.
But is organic food actually better for you?
Here's Associate Professor Tim Crowe, a nutrition expert at Deakin University in Melbourne.
"This is the big question, and there have been hundreds and hundreds of research studies done in this area, because you need to do that many studies to try and see if there's a difference, I mean, there's natural variation in nutrients, and foods can be hundred and two-hundred per cent higher just depending on what the time of year and how ripe, and what soil the food's grown in. But there's been enough research to show that there may be a slight edge to organic food over conventional grown food. But it is only a couple of key vitamins and minerals, and the levels are quite small, perhaps 20 to 60 per cent higher, for some nutrients in some foods."
University of Newcastle Professor of Nutrition and Dietetics and Dietician Clare Collins explains that in nutritional terms, organic is not obviously healthier.
"I think that generally all of the considerations, like for taste and nutrition, and being better for the environment are all rolled into that concept of being organic, yet when we drill down onto the nutrition, the evidence isn't really so clear".
But even if most organic produce doesn't pack more vitamins, there is also a question of taste.
A lot of consumers believe that organic food tastes better.
But Professor Crowe says it's all in our heads.
"If you tell people that a food is organic, they will tell you it tastes better whether it's organic or not. So consumers cannot tell the difference between organic and conventional produce, when you've got similar sorts of foods you're comparing."
It's quite easy to do a blind taste test.
Just present a person with two slices of tomato, and tell them that one of the slices is organic.
"Our taste is built upon expectation. That doesn't mean they don't taste good if you believe they taste good, they certainly do. But when you do blind testing, consumers cannot tell the difference between organic and regular fruit and vegetables."
Professor Collins explains why some produce does taste better.
"So generally the vegetables and fruit that taste better are the ones that are picked and then eaten not too long after they've been picked, and so that's not necessarily organic and it's not necessarily conventional; if ever you have been to a growers' market where the farmers come in with their produce, freshly picked, they're the ones that taste better, and often they're the ones that are grown a bit closer to where you live."
A great taste and rich nutrition are two things you definitely want in your vegetables.
But there are also things you don't want - such as pesticide residue.
Adam Willson explains that people want to avoid eating synthetic chemicals.
"The number one reason why people are going towards organic food is for health. And top of the list of that health is taking the chemicals out of your diet - number one, without a doubt."
In agriculture the word 'chemicals' usually refers to pesticides, synthetic substances used to get rid of weeds, pests, and other problems.
In Australia, produce is routinely screened for safety, including residues of most common agricultural chemicals.
Tim Crowe explains that organic food really does have less of them.
"This is one area where the research probably is fairly clear, that conventional grown fruit and vegetables do have higher synthetic pesticide residues. Now, should you be concerned about that? Well, the answer is no, because the levels are still extremely low."
Some organic farmers may also use pesticides but these have to be natural.
"Some of these natural pesticides can be just as harmful and dangerous if you give them in high enough doses to rats as synthetic pesticides. Now this does not mean that you should be concerned about organic food, not at all, but it puts things into perspective - we are always eating these levels of insecticides when we're eating food, and they're surrounding us all the time. So I would not be concerned about the levels of insecticides on conventional grown fruit and vegetables for that very reason."
In fact, it's more important to make sure you eat enough fruit and veg to start with.
Professor Clare Collins says that less than one in ten Australian adults eat the recommended daily amount of vegetables.
"The problem we have in Australia is that there's a massive gap between the amount of vegetables and fruit we know for good health, and what people eat. My concern around organic, or people thinking that the only vegetables and fruit you can eat is organic, is that it widens the gap in terms of being able to get people to eat more vegetables and fruit, because typically the organic produce is more expensive than the regular produce."
Nutrition expert Tim Crowe agrees.
"The organic food debate can be quite emotive - that people believe it will taste better, and they believe it will be better for them. And if you believe then that will probably be the case. If you can afford to buy them, by all means go and buy them - research is not saying that they are worse for you, and they may give a small health benefit. But our biggest health problems we face in Australia is actually just not eating enough good, healthy food to start."
But even if it's not tastier or healthier, there is one more aspect of organic farming and that's environmental friendliness.
All crops need fertilisers and the two most important ones are nitrogen and phosphorus.
These chemicals are vital to all life on Earth.
According to Dr Hobley, plants don't distinguish whether the source of a fertiliser is natural or artificial; to them it's the same chemical.
But there are other environmental impacts.
Nitrogen production for conventional farming is energy intensive and produces a lot of greenhouse gas.
Soil scientist Dr Nellie Hobley explains how farmers use phosphorus.
"Now, in organic farming you are actually allowed to apply rock phosphate, but it can't be treated, so they have to use natural rock phosphates or, potentially, guano. In contrast with this conventional agriculture uses superphosphates, which are basically rock phosphates that have been treated with acid, which makes that phosphate a lot more available for the plants, so that really promotes plant growth."
To get rock phosphorus, it has to be mined, and that has an impact on the environment.
Additionally, it's a limited resource, and it goes out with our waste through the sewage and into the ocean.
In organic farming, the recycling of manure leads to more effective use of phosphate.
So organic produce is often better for the environment but buying locally is another factor.
"The benefits of organic agriculture are such that you don't have the greenhouse gas emissions naturally associated with the production of your fertilisers, and your soil's a lot healthier, but if you're then importing your food from elsewhere, then you do have greenhouse gas emissions, you've got those food miles."
At the moment organic farming is not as productive as conventional farming.
It simply can't feed the world's population.
Organic farmer Adam Willson believes that organic farming will grow in scale, and also become more affordable.
"It has history. You know where it's coming from. And what you buy today is affecting the future tomorrow, and organics is a great thing to invest in, it's a great future."
Even though the market is increasing, we will need a change of attitude.
Regardless of whether you live in the city or not, this might be a good time to start your own home garden or join a local co-op.
"Gardening is a wonderful thing that brings people together, it's social and it actually makes you happy. And I would certainly recommend that people get back into gardening, as much as possible, and try and produce as much food as possible, because that will definitely be beneficial for the environment. But you don't necessarily have to do that organically."