Distribution, Characterisation, and Reclamation of Waterlogged Soils: A Review

Abstract

Waterlogged soils represent one of the most challenging constraints to global food security and sustainable land management, affecting an estimated 640 million hectares worldwide. This review synthesises current knowledge on the global distribution, paedogenic characterisation, and reclamation strategies of waterlogged soils. It examines geomorphological and climatic drivers of waterlogging across major agroecological zones, analyses soil morphological, physical, chemical, and biological characteristics under prolonged saturation, and critically evaluates established and emerging reclamation technologies. Evidence from over 150 peer-reviewed studies published between 1990 and 2024 was integrated. The findings indicate that waterlogging-induced anaerobic conditions trigger cascading redox reactions, including iron and manganese reduction, denitrification, and methanogenesis, which substantially alter nutrient cycling, soil structure, and microbial communities. Reclamation success depends on accurate diagnosis of the cause of waterlogging, integration of drainage engineering with biological and chemical amendments, and long-term monitoring. Future directions include precision drainage design, climate-adaptive management, and the use of remote sensing for large-scale waterlogging mapping. This review provides a reference for soil scientists, agronomists, and land-use planners managing waterlogged landscapes.