On Thursday 4 June 2026, the PhD Defence and Awarding Ceremony of Henry Amorocho Daza from Colombia, will take place.

His promotors are Professor Pieter van der Zaag and Professor Jill Slinger and his co-promotor is Dr. Janez Susnik.

The title of the thesis is:
Modelling the environment with stakeholders. Theoretical perspectives and practical applications for transboundary river management

The defence will take place at the TU Delft Aula, Mekelweg 5, Senaatszaal

& via Live Stream link

15.00 – 17.00              Presentation, Public defence & Awarding ceremony

Warning: you cannot enter the room after the presentation has started.               

Research Summary:
This dissertation engages with the wicked problem of agriculture-driven nutrient pollution in transboundary basins. The Lielupe River Basin, shared between Latvia and Lithuania, provides a practical example of this issue. This thesis proposes ways forward to address this problem by crafting and using environmental models in participatory and systematic ways.

Modelling the environment with stakeholders adopts a systems perspective in connecting theory with practice. Theoretically, we investigate how participation, uncertainty and ethics can be included in model development for socio-environmental problems. Practically, we explore the added value of implementing participatory modelling in transboundary river management using the Lielupe basin as a case study.

Researchers and practitioners can find two theoretical contributions: (1) a flexible 3-phase modelling framework for addressing socio-environmental issues; (2) a structured set of ethical questions when engaging in participatory modelling.

Empirical contributions are specific to the Lielupe River Basin yet provide insights that are potentially transferable to other cases. Our results indicate that moderate cooperative land-use change scenarios outperform ambitious unilateral actions, helping to achieve basin-wide water quality objectives a decade faster—a critical finding for the Baltic region and the achievement of EU water quality objectives. We also show that model evolution and participants’ learning are socially driven across and beyond a modelling cycle.

This thesis contributes towards a more reflective and transparent modelling practice. It provides environmental modellers with practical tools for jointly developing and using models with stakeholders. The dissertation concludes with a call to modellers to consider how modelling can support broader participatory engagement processes rather than how participatory engagement can support modelling.