Soil formation：练习题

• a.

  Biological weathering

• b.

  Mechanical fragmentation

• c.

  Chemical weathering

• d.

  Physical weathering

• a.They produce organic acids that chemically break down the surface of rocks.
• b.They cause rocks to shatter by increasing the temperature of the rock surface.
• c.They physically force rocks apart by the growth of large woody taproots.
• d.They act as decomposers that turn mineral matter into inorganic gases.

• a.It creates high pressure within rock fissures through the process of carbonation.
• b.It causes the oxidation of iron minerals, leading to the rusting and crumbling of rocks.
• c.It acts as a lubricant that allows soil particles to slide past one another more easily.
• d.It forms a weak carbonic acid that dissolves minerals like calcium carbonate.

• a.

  Temperature changes causing expansion and contraction

• b.

  The action of lichens and mosses on rocks

• c.

  The reaction of minerals with oxygen (oxidation)

• d.

  The dissolving of rocks by weak acids (carbonation)

• a.Humus
• b.Topsoil
• c.Parent material
• d.Silt

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。