Longitudinal Analysis of Policy Attention in South Korea’s Smart Farm Innovation Valleys: Issue Salience and Lexical Co-Mention Network Reweighting, 2019–June 2026

South Korea’s Smart Farm Innovation Valley program integrates infrastructure, technology demonstration, training, entrepreneurship, and public support across four regional sites. This study examines changes in documented policy attention to the program from 2019 to June 2026. We analyzed 15,455 news articles, blog posts, online community discussions, and web documents retrieved from Naver, Daum, and Google using TEXTOM. Across three national policy contexts, we examined normalized concept prevalence and cosine-weighted lexical co-mention networks, supplemented by frequency-adjusted association measures and a fixed-margin null model. Attention to construction and project delivery declined, while education, entrepreneurship, rental access, support, and operation became more prominent. Network comparisons revealed substantial continuity between adjacent contexts alongside cumulative relational reweighting over the study period. Node connectivity largely tracked concept prevalence, but selected lexical co-mention pairs involving operation, demonstration, and data changed beyond fixed-margin expectations. Manual semantic validation was heterogeneous: adjudicated temporal point estimates opposed the full-corpus lexical directions for four focal concepts, and the highlighted lexical co-mention links were not independently corroborated as semantic associations. The findings provide a systems-oriented account of how policy-related issues are jointly represented in public discourse; however, they do not establish changes in institutional coordination, operational capacity, or program effectiveness.