<P> An example of the development of a soil would begin with the weathering of lava flow bedrock , which would produce the purely mineral - based parent material from which the soil texture forms . Soil development would proceed most rapidly from bare rock of recent flows in a warm climate , under heavy and frequent rainfall . Under such conditions , plants ( in a first stage nitrogen - fixing lichens and cyanobacteria then epilithic higher plants ) become established very quickly on basaltic lava , even though there is very little organic material . The plants are supported by the porous rock as it is filled with nutrient - bearing water that carries minerals dissolved from the rocks . Crevasses and pockets , local topography of the rocks , would hold fine materials and harbour plant roots . The developing plant roots are associated with mineral - weathering mycorrhizal fungi that assist in breaking up the porous lava , and by these means organic matter and a finer mineral soil accumulate with time . Such initial stages of soil development have been described on volcanoes , inselbergs , and glacial moraines . </P>
<P> An example of the development of a soil would begin with the weathering of lava flow bedrock , which would produce the purely mineral - based parent material from which the soil texture forms . Soil development would proceed most rapidly from bare rock of recent flows in a warm climate , under heavy and frequent rainfall . Under such conditions , plants ( in a first stage nitrogen - fixing lichens and cyanobacteria then epilithic higher plants ) become established very quickly on basaltic lava , even though there is very little organic material . The plants are supported by the porous rock as it is filled with nutrient - bearing water that carries minerals dissolved from the rocks . Crevasses and pockets , local topography of the rocks , would hold fine materials and harbour plant roots . The developing plant roots are associated with mineral - weathering mycorrhizal fungi that assist in breaking up the porous lava , and by these means organic matter and a finer mineral soil accumulate with time . Such initial stages of soil development have been described on volcanoes , inselbergs , and glacial moraines . </P>
material that is weathered to become the mineral part of the soil
material that is weathered to become the mineral part of the soil
lava flow bedrock
lava flow bedrock