A Theoretical Framework for Modelling the Impact of Farmland Fragmentation on Crop Productivity and Food Security in the South East Zone

Farmland fragmentation, the division of agricultural land into small and geographically dispersed parcels, is an under-theorised yet pervasive land tenure phenomenon in South East Nigeria that affects management efficiency, input use, mechanisation access, and ultimately crop productivity and household food security at a scale that merits original theoretical development. This study developed an original theoretical framework for modelling the impact of farmland fragmentation on crop productivity and food security in South East Nigeria. A theory-building methodology combining spatial econometric analysis, productivity decomposition modelling, and empirical grounding was employed. Secondary data on farm parcel size, number, and spatial distribution were extracted from satellite imagery and ground truth surveys of 200 farming households in Imo, Enugu, and Anambra States. TFP decomposition analysis was applied to quantify the technical efficiency loss attributable to fragmentation. The original Farmland Fragmentation Productivity Impact Framework (FFPIF) proposes that fragmentation affects productivity through three pathways: increased transaction costs (movement between parcels), cultivation complexity costs (variety and practice changes across parcels to suit soil differences), and mechanisation access barriers (small parcel size below efficient machine operation threshold). Empirical analysis confirmed that fragmentation index was significantly negatively associated with TFP (coefficient -0.38, p < 0.001) after controlling for farm size, education, and market access. The framework was validated against secondary data from similar systems in Northern Ghana and Ivory Coast. Expert review by 18 agricultural economists and land use scientists confirmed the framework's original theoretical contribution. Keywords: farmland fragmentation, crop productivity, food security, South East Nigeria, land use theory