Pg.no. 99
This is probably the most important factor that can shape the formation of soils. Two
important climatic components, temperature and precipitation are key. They
determine how quickly weathering will be, and what kind of organic materials may
be available on and inside of the soils. Moisture determines the chemical and
biological reactions that will occur as the soils are formed. Warmer climate with
more rainfall means more vegetative cover and more animal action. It also means
more runoff, more percolation and more water erosion. They all help to determine
the kind of soils in an area.
Relief:
This refers to the landscape position and the slopes it has. Steep, long slopes mean
water will run down faster and potentially erode the surfaces of slopes. The effect
will be poor soils on the slopes, and richer deposits at the foot of the slopes. Also,
slopes may be exposed to more direct sunlight, which may dry out soil moisture and
render it less fertile.
Organisms:
The source and richness of organic matter is down to the living things (plants and
animals) that live on and in the soils. Plants in particular, provide lots of vegetative
residue that are added to soils. Their roots also hold the soils and protect them from
wind and water erosion. They shelter the soils from the sun and other environmental
conditions, helping the soils to retain the needed moisture for chemical and
biological reactions. Fungi, bacteria, insects, earthworms, and burrowing animals
help with soil aeration. Worms help breakdown organic matter and aid
decomposition. Animal droppings, dead insects and animals result in more decaying
organic matter. Microorganisms also help with mineral and nutrient cycling and
chemical reactions.