The Muencheberg Soil Quality Rating for Assessing the Quality of Global Farmland

Sustainable use of soils is a vital issue in the 21st century to meet global challenges of food security, demands for energy and water, climate change and biodiversity. Eurasia has reasons to tackle and solve these problems soon. It covers the largest landmass and has the highest population density of the earth. Tools for reliable, simple and consistent evaluation of the status of the soil over a wide range of scales can help to assess suitability for crop growth and yield potentials. We explain the Muencheberg Soil Quality Rating (M-SQR) for analysing soil properties that limit crop yields and crop productivity potentials consistently over large regions. The approach is based on 8 Basic Indicators and at least 12 Hazard indicators. Ratings of soil quality are made during normal soil survey mainly by applying visual methods of soil evaluation. A field manual provides rating tables based on response curves and thresholds for different hazard indicators (such as risk of drought). Finally, overall soil quality rating scores ranging from 0 (worst) to 100 (best) characterise crop yield potentials. The current approach is valid for grassland and cropland. Field tests in Eurasia confirmed the practicability and reliability of this approach. We conclude that the Muencheberg SQR has the potential to serve as a global functional reference framework for agricultural soil quality of cropland and grassland. We anticipate the creation of comparable soil functional maps of the whole of Eurasia by the use of this method.