Providing food for the growing world population requires more chemical fertilizers, and the production of traditional fertilizers requires a lot of energy. With energy prices rising, scientists are experimenting with mixtures of organic and chemical fertilizers to maintain crop yields but also to reduce carbon emissions.
In the middle of a hot summer day, this combine harvester is still working in the field harvesting barley for the winter.
This crop needs a lot of fertilizer, and traditional farming methods rely on mineral fertilizers.
Some estimates suggest that for every tonne of mineral fertilizer produced, four tonnes of carbon emissions are created.
This is a problem for the agricultural sector hoping to meet zero carbon emissions commitments.
In Luton Hoo, north London, there are 1,000 acres of arable farmland.
Farm managers have agreed to trial an organic-mineral fertilizer mix that promises to produce less carbon while adding benefits to soil health.
Professor Ruben Sakrabani is an expert at Cranfield University. He has explored the potential advantages of organic-mineral fertilizers and is conducting a field trial.
“The trial you see here is experimental work we’re doing to see the effectiveness of this new fertilizer. The crop we’re growing here is winter barley. Fertilizers are really expensive to produce and so we’re using a another that is cheaper to produce and much more environmentally friendly”.
Side by side, the two litters don’t look very different.
“To produce a mineral fertilizer requires a high amount of energy. That’s why with the high cost of energy at the moment even the mineral fertilizer has a high price. We are trying to use materials that are naturally present in agriculture, such as animal manure, plant residues, as one of the basic materials and adding a smaller amount of this mineral fertilizer to make it a mixed composition, which we call organic-mineral fertilizer”.
Of course, using animal manure to fertilize fields is not something new and has been practiced by farmers for centuries.
But now, scientists are able to optimize the ingredients and determine how much nitrogen should be added to the mix.
The move to organo-mineral fertilizers is being encouraged by farmers looking to reduce carbon emissions.
“We identified a long time ago that one of our biggest challenges is climate change and how we can mitigate some of the effects we are facing. We are at the forefront of efforts. For example, last year when temperatures it was 37-38C here on the farm, we had to stop harvesting because it was getting too hot, the machines were getting too hot,” says Edward Phillips, farm director at Luton Hoo.
Scientists from Cranfield University are measuring soil samples from the field and will measure nitrogen levels in the laboratory.
A test like this contains many parameters and no one area of the field is exactly the same as another.
This means it is even more important to measure soil health at all stages of planting and harvesting.
Farm manager Phillips is impressed with the results of the barley trial and says they plan to use an organo-mineral fertilizer mix across the farm in the coming years.
One of the potential benefits of organo-mineral fertilizers is its effect on the slow release of nutrients, which can help it compete with mineral fertilizers in terms of plant yields.
With the global population increasing every year and hotter summers making farming more difficult, many are considering more sustainable ways to feed the world’s population.
The use of organo-mineral fertilizers can be a way for a more sustainable agriculture.