Abstract
<title>Abstract</title> <p>Southeast Asia has experienced net cropland expansion over recent decades, but net area gains may obscure changes in cropland quality and spatial allocation. Here, we apply an integrated quantity–quality–space framework to annual 30-m land-cover maps and agro-ecological attainable yields for rice, maize and wheat to quantify cropland transitions and cereal food production potential (FPP) across 11 countries from 2000 to 2022. We define FPP as an upper-bound caloric production potential for three major cereals, rather than realized food production or overall food security. Total mapped cropland increased by 14.86 Mha, yet gross internal turnover reached 4.92 Mha yr⁻¹, comprising 2.77 Mha yr⁻¹ of expansion and 2.15 Mha yr⁻¹ of loss. Expansion was concentrated in land-cover classes mapped as forests and frontier uplands, whereas losses occurred through both built-up conversion and cropland-to-non-built-up transitions. Built-up conversion removed cropland with the highest average FPP, while newly expanded cropland was generally located in lower-potential upland and frontier settings. These spatial reallocations coincided with declining per-capita cropland and per-capita FPP, as well as rising cereal import dependence in several countries. Our results suggest that cropland expansion alone is an insufficient indicator of cereal-production capacity, and that land-use monitoring and policy should account for cropland quantity, quality and spatial configuration.</p>