WHEN it comes to the environment, interfaces are where the big action is.
Sometimes this action is dramatic: landslides, gale-force winds causing havoc in
forests, or rivers flooding farmland.
Of course, more often this interaction is less dramatic because the processes
occur over very long timescales, but the effects are just as important. The slow
but inexorable weathering of mountains is just one example.
And there is a vast interface zone that covers much of the global land
surface where the atmosphere, the hydrosphere, the biosphere and the geosphere
all meet. That zone is the soil; and it is both…
