1. The reduction in the capacity of the land to provide ecosystem goods and services and to assure its functions over a period of time for its beneficiaries. (LADA, 2009).
2. (in drylands) Reduction or loss, in arid, semi-arid and dry sub-humid areas, of the biological or economic productivity and complexity of rainfed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from land uses or from a process or combination of processes, including processes arising from human activities and habitation patterns. (UNCCD 1994).
3. Reduction of resource potential by one or a combination of processes acting on the land. These processes include water erosion, wind erosion and sedimentation by those agents, long term reduction in the amount or diversity of natural vegetation, where relevant, and salinization and sodication. (UNEP)