How phosphorus scientists envision creating a circular future
350 years of Phosphorus
In 1669, Hennig Brand accidently discovered phosphorus (P) while trying to create the “philosopher’s stone” in a sample of human urine. Three and half centuries later, scientists and researchers across the globe study the effects, impacts, and recoveries of P derived from human (and animal) wastes in terrestrial, aquatic, and interplanetary systems.
This past July over 220 P freaks, as we like to be referred (researchers, industrial partners, engineers, students), gathered at ETH Zurich from 31 countries to discuss current P related issues and triumphs at the 9th Annual International Phosphorus Workshop (IPW9). The multidisciplinary nature of the workshop sessions and keynote speakers, and the diversity of participants and excursions created an environment for discussions beyond one particular subject or research focus. The events gave the participants opportunity to explore new realms of P research and to receive an inside look at the P related research conducted in Switzerland.
IPW9 participants during the first workshop session. Photo: G. Crain
Participants enjoying an apéro above the city at the Dozentenfoyer. Photo: G. Crain
Nutrient recycling on Earth and beyond
As a doctoral student in the Group of Plant Nutrition at ETH Zurich, P is involved in all research projects in some way, including my own. I study the physiological responses of plants to human derived waste products in hydroponic (soilless) growing systems, specifically for lunar or Martian bases. However, the use of recycled wastes with a high nutrient recovery is not a new or foreign concept for terrestrial agriculture or food production. Thus, one of the major themes and discussion points of IPW9 was the idea of creating and maintaining a circular economy or closed system, specifically for P recovery.
When I think of a closed system, I think of a planetary base. For example, a lunar base is a sealed environment that protects organisms from the potentially toxic air, radiation, and pressure differences, while providing the essentials for survival (food, water, oxygen) on the surface of the Moon. To do so, we may create a bio-regenerative life support system that recycles everything to provide the essential components using a combination of technologies (i.e. waste treatment connected to crop production). Simply, all wastes (urine, feces, plant residue, CO2) are processed and utilized for food, water, and oxygen production.
Though IPW9 did not focus on interplanetary farming with a bio-regenerative system, the closed lunar base is a model for system closure on Earth. The recycling of animal wastes for agriculture has been in practice for centuries. With growing technologies and innovations, the complete recovery of nutrients from human and animal wastes is the goal in creating a sustainable closed system. However, developing and maintaining a circular future requires the collaboration and knowledge of a wide range of scientific disciplines and approaches ranging from engineering to material sciences to plant nutrition.
A circular future is possible
IPW9 provided the necessary platform to address this concern. Through facilitated discussions and spontaneous exchanges over coffee, the participants identified that there is a need for a more collaborative, global, and holistic approach in addressing system closure. There is a need to combine technologies, bridge knowledge gaps, include more players, such as underrepresented countries, policy makers, and farmers, and incorporate long-term studies and data. Developing a collaboration across multiple disciplines and strong communications is imperative in addressing concerns that have an impact beyond the lab or field plot.
Mixed group discussions during Day 4 of the meeting. Photo: G. Crain
Participants and helpers enjoying a boat ride across Lake Zurich. Photo: G. Crain
It was motivating to be among leading researchers from all over the world, not only identifying possible solutions for improvement, but also, doing so with a critical eye. In academia and industry, it is very easy to fall into old patterns or stay within a specific field of research, but in order to tackle an issue with a global impact, there is call on scientists and industrial partners to step out of their comfort zones. I believe these steps will allow the P and general community to better establish and utilize a collaborative, global, and holistic approach in creating system closure on this planet and others.
ABOUT THE AUTHOR
Grace M. Crain is a doctoral student at ETH Zurich with the Group of Plant Nutrition. Her research focuses on hydroponic crop production of traditional and alternative plants from human derived waste products for space missions as part of the European Space Agency’s project MELiSSA. Grace hopes to bring awareness to alternative farming methods through the intersection of plant and space sciences. When not at the research station, Grace enjoys exploring nature and watching movies