Human Dimensions of the Phosphorus Cycle

Phosphorus (P) is an essential element for food production. Society faces fundamental problems involving P. One problem is that mineral P reserves are finite and unevenly distributed, meaning that global fertilizer P production is dominated by few countries, akin to the situation for fossil fuels. Another problem is waste, as tremendous quantities of P are lost incidentally to rivers, lakes, and coastal waters, stimulating algae blooms and degrading water quality and associated services such as commercial fishing and recreation. To solve these problems, innovations in P use are needed, including technologies and policies that promote the judicious use of P as well as P recycling pathways. Because the majority of the global human population now lives within cities, opportunities for more sustainable P use are likely to be revealed through a better understanding of the major human P flows through society and infrastructure, including food waste and sewage, which contain recoverable P.

This workshop will focus on understanding and synthesizing data on P flows through people, cities, and infrastructure in five distinct international contexts, and developing a broader Pursuit proposal on these subjects. Understanding of the heterogeneity of these P flows, and the efficiency of P use, may help identify pathways towards sustainable management of this essential resource.

The workshop aims to increase understanding of two distinct human P flows that transport P from consumers to landfills as food waste and sewer infrastructure to arable soils as sewage biosolids. The products of the workshop are a scientific article on the variation of human P flows linked to socio-environmental context, synthesized data sets, and a broader SESYNC Pursuit proposal that aims to build on the findings, ideas, data sets, and relationships established.

The research questions are:

1. How large and variable are these P flows as food waste and biosolids, in different locations internationally?
2. How does socio-environmental context, including diet choices, infrastructure, governance, wealth, technological development, and social structure, influence the magnitudes and uncertainties of these human P flows, as well as our capacity to change them?