Dynamic Land Tenure, Investment, and Agricultural Productivity in the Context of Demographic Pressure in South East Nigeria: A Longitudinal Analysis

The relationship between land tenure security, agricultural investment, and productivity under conditions of demographic pressure and land scarcity has been theorised extensively but requires empirical refinement in the specific institutional contexts of South East Nigeria, where customary tenure systems are under significant strain from population growth and urbanisation. This study conducted a longitudinal analysis of dynamic land tenure systems, investment behaviour, and agricultural productivity in South East Nigeria using a four-round panel dataset of 380 farming households in Anambra, Imo, and Enugu States collected over a twelve-year period from 2012 to 2024. An innovative tenure dynamics index was constructed to capture changes in tenure security over time at the plot level. Panel fixed effects, difference-in-differences, and instrumental variable approaches were combined to identify causal effects on soil conservation investment and crop yields. Results demonstrated that tenure security improvements were associated with significant increases in long-term soil fertility investment and 18 to 24 percent yield improvements for yam and maize across the study period. Tenure deterioration had asymmetric and larger negative effects on investment than improvements had positive effects, consistent with an option value model of investment under tenure uncertainty. The study makes original theoretical and methodological contributions to the land tenure-investment literature, with policy recommendations for customary tenure documentation reforms. Keywords: land tenure, agricultural investment, productivity, South East Nigeria, panel data.