Soil Biology Primer (from National Resources Conservation Service)
"...How Tiny Microbes Make Life Easier for Humans..."People think you're going to pick up a handful of dirt anywhere in the world and you'll pretty much have the same bunch of microbes doing pretty much the same things...That's simply not true. They function very differently based on their environment. And when you have more species, you get more, and different functions."...[they] provide critical ecosystem services, such as fertile soil and clean water..."