ABSTRACT
Soil security is critical to human security (Minami, 2009) and underpins food and water security (McBratney et al., 2014). Humans have observed variations in soil properties and especially its fertility since the advent of settled agricultural societies. Until the emergence of modern science in the seventeenth century, this assessment was subjective and experiential, and this remains an important approach for many farmers (Romig et al., 1995). However, science has revealed insights into the working of the soil system and its role in supporting agriculture and the wider land system, leading to more objective and quantitative assessments of soil quality and health. Interest and studies in this area have been intense over recent decades, but a final understanding of how best to assess soil status remains elusive. This chapter outlines some theories of the soil system and applies this to clarify the meaning of ‘quality’ and ‘health’ as they apply to soil. It explores how to assess soil health and provides a commentary on which indicators of soil health may be useful in practical agriculture. It underlines the importance of soil governance and how this may be optimized.
