ABSTRACT
This chapter explores the biological considerations key to creating a sustainable harvest. The rise of agriculture is described, along with various agricultural innovations such as the Green Revolution, which aimed to increase crop yields to tackle hunger globally. However, the boost in crop production also requires additional nutrients to grow these crops, so the role of various inputs like fertilisers is discussed, including the sustainability of their production such as through mining of phosphorus. Then the role of soil life like fungi and bacteria, which converts inputs like fertiliser or dead plant material into a form that can be used by plant, is explored as an often forgotten key part of the cycling of nutrients. Following discussion of different agricultural systems like monocultures or companion planting of the three sisters, in relation to sustainability, the chapter concludes by asking what, precisely, are we trying to sustain with sustainable agriculture? Is it human survival or unlimited choice of food types, and how does this affect the trade-offs we are willing to make in terms of unknown impacts of genetically modified organisms, for example? After discussion about the closed, cyclical nature of sustainable agriculture, the chapter ends with a reflection on global food security.
