Near the soil surface, in the first meter or so of soil (the root zone of most plants) is defined as the distribution layer or top soil, composed mostly of homogenous soil.
(the root zone of most plants; is defined; as the distribution layer or top soil; L:Near the soil surface; L:in the first meter or so of soil) (top soil; composed; mostly of homogenous soil)
the root zone of most plants top soil
is defined composed
as the distribution layer or top soil L:Near the soil surface L:in the first meter or so of soil
mostly of homogenous soil