Pathways for sustainable phosphorus loop in Germany: Key lessons from stakeholders' perspectives

Abstract Phosphorus (P), being a soil macronutrient, is known to contribute to eutrophication when in excess and to impede plant growth when in short supply. The management and sustainable use of P have been major topics for research. Germany, in particular, has made significant advances in P management through concrete action, including technology for P recovery, amendments to ordinances to make it mandatory to recover P from sewage sludge, and active stakeholder dialogue through a common platform, namely the German Phosphorus Platform. The study takes Germany as a case to understand the existing institutional arrangements for P management by analysing the current P discourse from stakeholders' perspectives based on in-depth interviews of ten key experts, each representing a different stakeholder group. A systematic analysis of the interviews, using the problem-and-solution tree (PAST) tool, revealed that institutional fragmentation and absence of dialogue between some categories of stakeholders were the main challenges to effective management of P. Other challenges include lack of technology upscaling and those related to economic, behavioural, and cultural matters resulting in lack of market for recovered P. Potential solutions for Germany include defining roles and responsibilities of different stakeholders more clearly, encouraging greater communication among stakeholders, ensuring greater transparency, strengthening market links, incentivizing farmers and consumers to accept P recovered from sewage, and developing innovative options to decrease the demand for P through behavioural changes, such as moving from P-intensive meat-based diets to less P-intensive vegetarian diets.