Underuse of phosphorus-based fertilizers in Africa currently contributes to a growing yield gap—the difference between how much crops could produce in ideal circumstances compared to actual yields.
This phosphorus-specific yield gap currently lies at around 10% for subsistence farmers, but will grow to 27% by 2050 if current trends continue, according to a study published today in the journal Global Change Biology.
“This research shows that the imbalance between nitrogen and phosphorus applications has the potential to further limit food production for a growing population in Africa” says Marijn van der Velde, a researcher now at the Joint Research Centre of the European Commission, who led the study while working at IIASA.
While nitrogen-based fertilizers can be produced by a process that extracts the element from the air, phosphorus must be mined from rock—and reserves are limited. That makes phosphorus fertilizers expensive, especially in the longer term.
“Farmers with limited money are more likely to buy and have access to cheaper nitrogen-based fertilizers,” says van der Velde. “While this might work in the short term, in the longer term it has a negative effect on crop growth as soil nutrients become more imbalanced.”
As farmers use fertilizers for their crops, nutrients such as nitrogen and phosphorus build up in the soil, providing a reserve of nutrients that plants need to grow. But fertilizer use remains very low in Africa, and to increase crop production, it is widely recognized that farmers must increase their fertilizer use. And while nitrogen-based fertilizer usage has begun to increase in Africa in the last 10 years, the application of phosphorus to cropland has not kept pace, leading to a growing imbalance between nitrogen and phosphorus levels in soil. The new study shows that increases in nitrogen and phosphorus inputs must happen in a way that provides crops with the balanced nutrient input they need.
The study used data from Food and Agriculture Organization (FAO) crop trials as well as an established EPIC large-scale crop model to estimate how the imbalance affects current and future crop yields.
“Previous research has looked at these effects on a field and local scale, but this is the first study to do so at the continental scale,” says IIASA researcher Christian Folberth, who also worked on the study.
In order to make optimal use of current nitrogen inputs, the researchers estimated that phosphorus applications would need to increase 2.3-fold. To close yield gaps nitrogen applications would have to increase 5-fold. Phosphorus applications would have to increase nearly 12-fold from 2.2 to 25.9 kg per hectare.
But because of the cost of phosphorus, that remains a challenge. ”While much of the remaining phosphorus reserves are found in Morocco, on the African continent, we need to find better ways for African farmers to access this precious resource” says van der Velde.
The global phosphorus cycle is, besides nitrogen, also increasingly growing out of balance with carbon, the subject of another recent paper by the same group of researchers and a new European Research Council grant for continued research by IIASA and an international team of scientists.
“The change in the stoichiometry of nitrogen and carbon from rising atmospheric CO2 concentrations relative to phosphorus has no equivalent in the Earth’s history and the impacts will go beyond the agricultural sector.” says van der Velde.Reference
ContactsMarijn van der Velde
Katherine Leitzell | idw
Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung
High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences