ABSTRACT
Soil is alive. Very alive. The total mass of living material in a typical arable soil is about 5 tonnes per hectare-in grasslands and forests it can be 20 times this, such that the biomass belowground always equals and sometimes exceeds that aboveground. In a handful of such arable soil, there will be 10 billion bacteria, scores of kilometers of fungal hyphae, tens of thousands of protozoa, thousands of nematodes, and hundreds of worms, insects, mites, and other fauna. Life in soil is diverse. Very diverse. The genetic diversity of the soil biota always exceeds that found aboveground and
29.1 Introduction .......................................................................................................................... 379 29.2 The Set ..................................................................................................................................380 29.3 The Cast ................................................................................................................................380
