ABSTRACT

Soil may be regarded as a complex bioorganomineral system where minerals, water, air, organic matter (OM) (humus), and microorganisms interact at scales ranging from nanometers to kilometers. Figure 2.1 gives a simplied diagram of the clayhumus-microbe in soil. In this chapter, we focus attention on the interactions of clays with OM, a process that is arguably as important to sustaining life on earth as is photosynthesis (Jacks, 1973). ¤e clay-organic interaction plays a key role in stabilizing soil OM against microbial decomposition, thus making soils suitable for plant growth, while photosynthesis produces biomass for inputs into soil, as well as for human and animal consumption.