Mapping Postharvest Losses in Red Chili Value Chains Using System Dynamics: A Case Study of Pakistan

Postharvest losses (PHLs) are the most significant issue affecting red chili value chains in Pakistan, undermining their overall competitiveness and performance. Sindh is the major chili‐producing province, with clusters in the Kunri and Umerkot districts of its Mirpurkhas division. The literature on the extent of PHL in horticultural value chains in Pakistan is scarce and reported in an isolated, stage‐specific manner. This study utilized a system‐wide approach, proposing that PHLs result from an interdependent relationship among value chain actors, processes, and institutions. We used a qualitative, field‐based approach with value stream mapping and system dynamics to examine the causes of PHLs in three major markets: Karachi, Lahore, and Faisalabad. The data were collected through informal discussions, focus group discussions (FGDs), semistructured interviews, and direct observations of both upstream and downstream actors. The structured process‐mapping tables described the steps, holding times, and loss mechanisms within the chains. The collected data were integrated to construct a causal loop diagram (CLD). The findings revealed that the losses are systemic and cumulative across all markets and are compounded by postharvest inefficiencies. The CLD found that stage‐specific interventions are less effective; reducing PHL with a single intervention is not possible unless connected feedback loops, such as increased storage capacity, market information systems, and quality management systems, are also modified. The study's findings contribute to understanding PHL as a systemic phenomenon and will help policymakers implement effective policies.