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Students help increase crop production in Peru

September 04, 2013

A new company started by Arizona State University students will help farmers in Peru, and eventually in other under-developed countries around the world, to cost-effectively increase their crop production with the use of an ancient method of soil improvement called terra preta, or “dark earth.”

Terra preta involves mixing charcoal – or biochar, created from agricultural waste – with natural local fertilizers to create a soil that is very dark and fertile. Biochar improves the soil quality by acting like a sponge, absorbing and storing plant nutrients and soil moisture. Due to the rich charcoal content, the soil also extracts substantial amounts of carbon out of atmosphere, helping prevent global warming.

The company, Growth Alternatives in Action (GAIA), started as an in-class project in the “Make Your Ideas Happen” class at the College of Technology and Innovation, and is now on its way to becoming a nonprofit organization with a global footprint.

“We started with a team of eight students researching the method and the decomposer system that makes biochar,” said Kathleen Stefanik, a junior in the college's industrial and organizational psychology program. “When the class ended, a few of us weren’t ready to leave the project so we took it to the next level.”

This summer, work continued as Stefanik, along with James Nelson, a mechanical engineering major, and Jesus Garcia-Gonzalez, an applied biological science graduate student, developed a prototype of a pyrolizer – the decomposer system that turns agricultural waste into biochar – out of materials that farmers would already have. It was important to the team that the process would be simple, sustainable, reliable and something farmers would be able to construct themselves, without any additional costs or resources.

“It was really encouraging to watch a team of students from different majors and with different strengths come together to tackle an agricultural problem that has global impact,” said Mark Henderson, team mentor and executive director of GlobalResolve, a program in the college with an array of sustainable technology projects in ten developing countries.

“We started by building prototypes of the pyrolizer in the Startup Labs on the Poly campus,” said Stefanik. “What we ended up with was a 55-gallon drum with a lid, with a chimney made out of corrugated aluminum. The total cost of the system was less than $25, but it was made out of materials that most farmers already have access to.”

The team then tested the pyrolizer by making biochar from weeds pulled out of abandoned garden plots at the Poly Community Garden.

“Using the pyrolizer isn’t difficult, but there is a learning curve,” said Stefanik. “You have to know right when to cut the oxygen, otherwise you get ash or weeds that are still green. We quickly realized that knowledge transfer was going to be the most critical step in getting farmers in Peru or other developing countries to implement the terra preta method.”

This June, Garcia-Gonzalez, Henderson, Abiola Doherty, an applied computer science major, and Gerald Polesky, an instructor for the college's technological and entrepreneurship management program, traveled to two small mountain villages in Peru where they worked with local farmers, teaching them how to make and use biochar to improve their income.

“Before we left for Peru, we were able to partner with Andes Libres, a non-profit organization in Peru, to help get a couple of farmers interested in trying terra preta methods so we could test the progress during our visit,” said Garcia-Gonzalez. “When we were on the ground in the community, we worked with more farmers to teach them the method and even taught classes at a local university about the project. Those students were then able to accompany us to one of the communities where we demonstrated how to make the biochar.”

Stefanik says that the test plots that the team helped the farmers to plant should be showing results of the method shortly. The team hopes that the test plot can be used to demonstrate to other local farmers the benefits of using biochar and that over time, other farmers in the area (and hopefully the region) will realize the economic benefits of terra preta.

The GAIA team say they hope to turn their company into an ongoing and sustainable nonprofit that will expand to other global initiatives surrounding agriculture, education and sustainability in the developing world.

“With the right team in place, I know we can continue to help people around the world,” said Stefanik.