Stanford University

*** Ph.D. Thesis/ Oral Defense ***

 

Risk-Management in Rural Bangladesh: Characterizing Livelihood and Health Trade-Offs in a Highly Season Environment

 

Ian Harryman

Thursday, May 21, 2026, 9:30 AM

Green 365

Department of Earth System Science

Advisor: Dr. Jamie Jones

Social relationships can have multidirectional impacts on health outcomes. Social support systems can buffer against certain adverse health outcomes such as food insecurity, while also creating potential pathways for infectious disease transmission. These effects have immense consequences for rural populations whose livelihoods are anchored to local environmental conditions. In this dissertation, I identify the functions, benefits, and costs of social networks for managing livelihood risks and health in a highly seasonal environment. From January to September 2024, I collected panel social network data in rural Bangladesh during rainy and dry seasons in four communities with distinct livelihood strategies. In July 2024, a political revolution briefly disrupted daily life in Bangladesh but also offered an unforeseen opportunity to observe socio-economic responses to an extrinsic shock. In Chapter 1, I explore the seasonal characteristics of informal support practices and their role in mitigating food insecurity. I find that informal support networks are both dynamic and effective at reducing food insecurity. In Chapter 2, I examine how economic support networks responded to the shock of a political revolution. I show that informal economic networks consolidated inward during a period of acute uncertainty, producing redundant and expedient pathways for monetary and resource flows. Finally, in Chapter 3, I generate simulated respiratory disease models to investigate how seasonal infection risk is mediated by social-contact structures and find that infection risk is shaped by livelihood responses to seasonal variability. These results show that densely connected contact networks facilitate livelihood risk-management, but can also produce amplification hubs for communicable diseases. This dissertation illustrates the trade-offs associated with managing health and livelihood risks in a highly seasonal environment.