A synthesis on fundamental principles and problems in the use of hydrological models for planning watershed conservation

Abstract This thesis is a synthesis that organizes the conceptual and philosophical foundations for the use of hydrological models in planning watershed conservation and expansion of green infrastructure. With the aim of creating an integrated map of ideas, the work not only connects theoretical and practical foundations but also offers a structured guide for future investigations and applications in the field. The initial chapter presents the epistemological bases, addressing the justifications and limitations of hydrological models. The second chapter develops an ontological approach with Systems Dynamics, exploring how model architecture defines hydrological responses and identifying points for strategic intervention. In the third chapter, the thesis reviews the evolution of hydrological paradigms, culminating in the Theory of Connectivity, which proposes an unification of surface and subsurface flow processes. The final chapter explores the role of Ecological Economics in watershed management, using the PLANS model in Payment for Ecosystem Services (PES) schemes to prioritize conservation areas at the operational scale of the farms. By synthesizing these concepts, the thesis establishes a structured body of knowledge that facilitates the advancement of new research, enabling the scientific community to articulate sustainable and adaptive solutions for watershed management with greater clarity and objectivity. Files thesis_{version}.zip - Source code and figures; thesis_{version}_en.pdf - Thesis in English; thesis_{version}_pt.pdf - Thesis in Portuguese; thesis_lecture_pt.pdf - Lecture in Portuguese. drawings.zip - Editable SVG figure files. Github repository: https://github.com/ipo-exe/thesis Version log v.0.6 - Minor edits for publishing in IPH Library. v.0.5 - Minor edits and font change. v.0.4 - Version after academic board minor revision. Includes all updated features and SVG editable files. v.0.3 - Version sent to the academic board. Includes the thesis PDFs in Portuguese and English, a lecture in Portuguese and the ZIP for the source LaTeX code and JPG figures.