Growth industry

From the pasta shortage at the local supermarket to the growing popularity of allotments, the UK is beginning to recognise the grim possibility that the age of cheap and plentiful food is coming to an end.

And while here in the well-fed West this spells minor culinary inconvenience or Sunday-supplement friendly lifestyle changes, the problems are more keenly felt elsewhere.

Last month, in his first major speech, Prof John Beddington, the government’s new chief scientific adviser, claimed the impending food crisis is the biggest challenge facing humanity. He warned that due to a combination of decreased rainfall, extreme weather events linked to climate change, and a world population expected to grow from six to nine billion by 2050, many developing world countries are once again staring into the abyss. And this time the West may be too worried about its own food supply to help out.

This is because at a time when more space is required for cultivation, the amount of available land is actually decreasing. Urban sprawl, the burgeoning biofuels industry and the growing appetite for meat among the emerging middle classes of south-east Asia, China and India are all limiting the amount of land available for food crops.

Experts agree that the world food supply needs to increase by 50 per cent by 2050, so the pressure is on the farming industry to come up with solutions. And engineering endeavour, which has walked hand-in-hand with farming since the dawn of organised society, has a tremendously important role to play.

One of the most promising developments is the emerging area of precision farming, where GPS-guided agricultural machines, armed with a detailed knowledge of a field’s varying characteristics, place seeds, fertilisers and nutrients where they are needed most.

Mark Moore, head of precision farming at tractor manufacturer Massey Ferguson, explained the theory. ‘We’re starting to tailor our inputs according to crop needs rather than taking the traditional blanket approach. For example, depending on soil fertility some areas of a field are better at producing a return than others. Having identified those more fertile parts we can increase profitability in those areas and apply inputs accordingly.’

Although the idea is not new, agribusiness consultant Neil Cameron believes precision farming is finally coming of age. ‘People have been playing around with it for years, but in the last 18 months we’ve hit a place where the equipment’s got cheaper, and the accuracy has got better and better.’

While this has much to do with the ever-improving resolution of satellite systems, one of the main reasons the approach now holds such promise is the advanced performance of today’s agricultural machines.

Today’s tractors, mainly GPS-guided and able to steer themselves, and combines have relegated the driver to the role of passenger. And there is more to come.

Earlier this year, agricultural machinery giant John Deere took the technology a step further with the launch of iTEC pro, a system that automates not only the steering, but also all of a tractor’s operations. ‘Pretty much from the moment you enter the field and set to work the operator is just a passenger,’ said Mark James, the company’s product manager for agricultural management solutions.

Moore sees similar trends on Massey Ferguson’s machines. ‘We’re very close to total autonomous vehicles,’ he said. ‘The operator doesn’t have to do much until something goes wrong.’

John Deere’s iTEC pro system automates all of a tractor’s operations

However, the prospect of armies of driverless robots toiling in the fields while the farmer sits at a desk at home is remote, said James. Not only would fears of 300hp combine harvesters hurtling out of control halt such plans, but there is always likely to be a need for on-site human expertise. The real benefit of automation, he said, is that it enables more efficient use of the driver’s expertise by freeing him from having to drive in a straight line for hours.

James added that while humans might not be completely removed from the loop, we may soon see operators driving one machine while a succession of driverless vehicles follow on behind. ‘On a multi-pass operation like planting potatoes — when there’s three or four operations — one man could potentially do this on his own but with a succession of different machines. Then you’ve got the experience in the operation, rather than expecting an automated system to make all the decisions.’

But while mechanisation helps address many of agriculture’s concerns, it is not without problems. One concern is the impact of increasing numbers of heavy machines on soil quality.

‘Over the last 70 or 80 years we’ve increased our vehicle weights dramatically and there are a lot of detrimental effects in terms of soil compaction,’ said agricultural engineer Tim Chamen.

Compacting the soil reduces its porosity and this, he said, is ‘bad news for drainage, for the plants, and for nutrition. The crop roots can’t explore all of the soil.’

Chamen believes the solution is controlled traffic farming, a satellite-based technique that minimises the impact of farm machinery by attempting to keep vehicle tracks in the same place year after year. Somewhat more sophisticated than the GPS techniques already used, the system required an additional ground base station to provide a signal that compensates for the movement of the satellite and provides accuracy over long periods of time.

Chamen is spearheading a practical demonstration of the concept across nine fields at Unilever’s research farm in Colworth, Bedfordshire. The project, set up to get UK farmers enthused about the concept, has had mixed results. Chamen said while enthusiasm is growing, the traditional conservatism of UK farmers is standing in the way of change.

‘There’s a lot of tradition in farming, there’s a lot of “I don’t want to be the first to be making a mess of things”. They’re a very traditional part of the population that don’t want to be seen to fail by their neighbours — they’re conservative about trying something new.’

But the role of satellites is fast becoming more sophisticated than simply ensuring that farm machinery sticks to a pre-planned route. Farmers are increasingly investigating the idea of observing their crops from space, where the tell-tale signs of disease and drought can often be spotted far more quickly than by someone on the ground.

The approach is already proving popular in France, where 10,000 farmers have signed up to FarmStar, a service based on a system of four low-altitude satellites that can tell them how well their crops are growing.

Henri Douche, a spokesman for Infoterra, the company behind the system, explained that the satellites use multi-spectral imaging techniques to analyse 10m² sections of farmland.

This approach captures light from a range of frequencies beyond the visible, and uses this data to calculate factors such as leaf density in specific areas of a field. Based on these images, the system then generates crop management advice, which is sent to registered users. Douche explained that users will then feed these recommendations into their farm management systems where they will, for instance, direct farm vehicles to spray more herbicides or fertilisers on specific areas of the fields.

However, the problem with satellite imaging is that it requires clear skies. So here, in the perpetually gloomy UK, a team of engineers and scientists is investigating the possibility of using military-style UAVs to survey farmland from the beneath the clouds.

Under the UMAP project, researchers from the Institute of Grassland and Environmental Research in Aberystwyth have joined with Qinetiq and Boeing to develop a UAV that will fly over field plots and gather crop information using hyperspectral imaging — a more powerful technique than multi-spectral imaging.

Dr Alan Gay, the project’s leader, said as the plane flies over the crop, a digital camera takes a series of images at different parts of the colour spectrum. Special computer software analyses the data, picking out subtle signs of the disease. Gay added that as well as picking up the signs of disease, the technique can also detect whether plants are receiving too much or too little fertiliser.

Meanwhile, Dr Bruce Grieve, director of the Syngenta Innovation Centre at Manchester University, (The Engineer, 12 November 2007) believes the solution could be even closer to the ground.

In fact Grieve, a sensors specialist, sees great promise in the concept of placing networks of crop monitoring sensors beneath the soil. He revealed to The Engineer that he is assembling a consortium to bid for a share of the £10m government funding set aside for ‘gathering data in a complex environment’.

Such sensors could, he said, gather information on crop stress and moisture content and relay this directly to tractors and combines via a farm management system.

However, he does not believe that a ground-based system will completely replace aerial approaches. ‘The monitoring of crop disease and crop stress is one that involves collecting data from a very wide area — this type of network will not replace satellite imaging but it will step in when satellite imaging is compromised by things like cloud cover, or when changes in barometric pressure start affecting the measurements from a long distance away.’

Massey Ferguson’s Moore is intrigued by Grieve’s ideas: ‘I think it’ll take the machinery and the agronomic worlds a bit closer together, but if sensors can relay messages in real time to a computer back at the farm office and that can influence the application plan, then so much the better.’

Moore added that while much of the technology already exists to make plans such as Grieve’s a reality, the problem is bringing all this data together and making sense of it. ‘The big challenge is there’s a lot of information around at the moment but there’s not much in the way of data fusion.’