Advances in visual soil evaluation techniques

Soil structure is a complex and dynamic soil property that constitutes a key aspect of soil health. Soil structure assessment can be evaluated in the field by visual soil evaluation techniques. Development and improvement of these techniques/methods have been the focus of numerous soil scientists worldwide since the mid-20th century. Divided into topsoil and soil profile methods, they differ in principle and level of detail of the assessment. The development and protocols of selected methods are presented in this chapter in chronological order of development, to show differences in methodological approaches. The description given for each of the methods includes guidance for the appropriate selection of the method to be used by stakeholders. Two case studies are given as examples of i) how visual techniques can contribute to achieving the challenges for developing sustainable agricultural management focused on nurturing soil fertility, and ii) the use of visual techniques as tools to assess and monitor soil health in developing countries.