PhD defence William Cardona
William Cardona (ConsEco)
Promotores: Prof. P.A. Tittonell, Prof. J. Falcao Salles; copromotor: Dr M.M. Bolaños Benavides (AGROSAVIA)
Grounds for Peace
A social-ecological assessment of soil health, diversification, and associated ecosystem services in Arabica coffee crops in post-conflict tropical lowlands of Colombia
Sustainable agricultural transitions are critical for addressing climate change and improving rural livelihoods in Colombia's tropical lowlands under a post-conflict context. This thesis investigates whether Arabica coffee can serve as a viable, resilient alternative to coca cultivation for smallholder farmers in Southern Meta. Drawing on social-ecological systems and sustainable livelihoods frameworks, the research combines household archetype analysis, soil enzymatic and DNA-based microbial studies, whole-farm bioeconomic modeling (FarmDESIGN), and farmer perception research (Q methodology) to examine how diversification, soil functioning, and farmer decision-making interact in these transitions.
The findings show that households respond heterogeneously to coca-to-coffee transitions, forming distinct archetypes shaped by market integration, labor organization, and agronomic management; that diversified agroforestry systems with shade trees, crop associations, and organic inputs enhance soil enzymatic activity, microbial diversity, and network connectivity compared to monocultures, particularly in highly weathered acidic soils; and that integrating coffee with livestock and other crops improves economic sustainability and nutrient recycling, though this comes with trade-offs in labor demands, management complexity, and greenhouse gas emissions, with some smallholders still unable to reach a living income due to limited land. Farmers' perceptions, shaped by climate uncertainty, labor scarcity, weak institutional support, market volatility, and past project failures, are essential to understanding coffee's long-term viability and reveal divergent views on whether diversification offers genuine resilience.
The thesis concludes that coffee can meaningfully contribute to peacebuilding and rural transformation in Colombia's tropical lowlands, but only when cultivated within diversified, ecologically resilient, and socially inclusive systems backed by long-term institutional commitment and tailored to local household realities.