A review of the available cropland and land cover maps for South Asia

Abstract. A lack of accuracy, uniqueness, and systematic classification of cropland categories, together with long-pending updates of cropland mapping, are the primary challenges that need to be addressed in developing high-resolution cropland maps for south Asia. In this review, we identify the major concerns, particularly the paucity of knowledge regarding the spatial distribution of major crop types within south Asia, which hinder policy and strategic investment and delay efforts to improve food security for a rapidly growing human population at a time of constant market instability and changing global climate. We specifically focus on the various available land cover and cropland maps at national and regional scales in south Asia and at the global scale, and describe the classification methods and approaches used for satellite images of different spatial resolution at different scales. The overall focus of this paper is to review the need for timely updated high-resolution cropland maps of south Asia.