ABSTRACT
In most terrestrial ecosystems, the soil surface-the zone from the uppermost, organic matter-rich layer of soil to the top of the litter or humus layer-supports a diverse community of organisms playing important roles in the dynamic processes of the entire system. In addition to a variety of plants, this community is made up of populations of spiders, mites, insects, myriapods, molluscs, annelids, roundworms, reptiles, amphibians, moles, small rodents, bacteria, protozoa, fungi, and other organisms, functioning variously as herbivores, predators, parasites, decomposers, and detritivores (Chapter 8 of Agroecology: The Ecology of Sustainable Food Systems).
