Let me begin by asserting that our soils are a tremendous source of enchantment.
My Dictionary of Geologic Terms (American Geologic Institute) defines soil as: earth material which has been so modified & acted upon by physical, chemical & biological agents that it will support rooted life. Curious that "rooted-life" is the true metric. And from the Soil Science Society of America: the unconsolidated mineral or organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants. Gee, why are we being so root-centric? R.J. Huggett's Geoecology comes with this suggestion: soil is rock that has encountered the ecosphere. Certainly more inclusive. But why not just this: Soil is where ever organisms live & die in or upon earth material. The tree-pit in the union of trunk & limb that helps to flourishes the orchid; the lichen on rock face or fence rail
& even lithotropes (stone-supping bacteria) 100 meters deep. In this sense dirt's key feature is indeed the support of the living (& the fertility of the dead), but not for the importance of plant life alone.
As for the notion of "ecosphere" & its cousin the "biosphere" take your pick. Either essentially means: the vivid presence of Life upon a planet ruled by a benevolent Sun. The former wishes to draw one's attention to the concrescence of biosphere, geosphere & heliosphere; whereas the latter emphasizes the touch-stone of Life as the necessary spark to ignite the animating blaze of the many "ecosystems" that illuminate this Earth.

Since there is evidence of a subterranean microbial biosphere beneath our feet (kilometers deep!), the celebrated diversity of our planet's surface must make room at the table for those communities in the Earth's crust--- and perhaps as forbidding a place as the Earth's "mantle" as well. Temperature & not
depth appears to be the primary limiting factor, and since there are areas of penetration among the large geologic layers--- archipelagos of crust sweeping out into plasticities of mantle, and in turn island chains of mantle bubbling up in the hot & solid core--- Life may have migrated near to the center of it all! What brave new worlds the disciples of island biogeography have before them!
With emphasis upon the ubiquity & immensity of microbial life, a revised taxonomy has been proffered. The "Kingdoms" of Plant, Animal & Fungi are now just three modest branchlets upon the bough of Eukarya, (taxonomists, like soil scientists are still pretty must "plant-centric"--- it really shouldn't be a "bush" but rather a complex of "land-forms" a geologist might study--- then would they be forced to account for the great endeavors of Death; all the shedding of Life that contributes to the selection of canonical DNA). The other two boughs, Bacteria & Archaea, emerging from a matrix of mysterious roots not even studied speculation has done much to identify---perhaps one day scientific inquiry will settle upon the truth that it is the earth itself. No one can say how useful such a scheme shall be in a hundred years, but I imagine that revisions will only continue to reduce the biological importance of multicellular organisms even as "microbes" rise in ascendancy.
With this rise will come a revolution in how we identify & define Life here on this third planet from the sun as well our "dead sibling" the moon and many more of the tribe in our heliosphere and those of a considerable, nay, infinite other.
With time will come a further parring--- but such a whittling as to reveal in the last fine grains the urancestor that began it all?