How Is Soil Formed?
The formation of soil happens over a very long period of time. It can take 1000 years or more. Soil is formed from the weathering of rocks and minerals. The surface rocks break down into smaller pieces through a process of weathering and is then mixed with moss and organic matter. Over time this creates a thin layer of soil. Plants help the development of the soil. How? The plants attract animals, and when the animals die, their bodies decay. Decaying matter makes the soil thick and rich. This continues until the soil is fully formed. The soil then supports many different plants. Weathering: Weathering is the process of the breaking down rocks. There are two different types of weathering. Physical weathering and chemical weathering. In physical weathering it breaks down the rocks, but what it’s made of stays the same. In chemical weathering it still breaks down the rocks, but it may change what it’s made of.
Soil is rock in its final state of decay. After millions of years of weathering it has broken down to fine mineral particles, the composition of the original rock and the processes which have acted on it, have determined its present form. Water, wind, movement, chemical action and varying temperatures act on the rock dividing it into smaller and smaller particles. In most of the British Isles the soil is unlikely to be sedentary, ie. formed directly above the parent rock with a gradient of particles becoming fissured rock as you dig down. The soil here in Northern Ireland is transported soil which was moved great distances during the Ice Ages and has a definite boundary between soil and the bedrock on which it was deposited. Igneous rocks, eg. bassalt, were the first to form when the molten lava cooled, then the erosion began. The process is sometimes reversed producing sedimentary and metamorphic rocks by compression, chemical action or extreme temperature. Sandstone is formed by chem
soil is the uppermost layer of the crust on the earth and contains a mixture of mineral matter,such as sand clay.it also contains organic matter such as decayed leaves,flowers,minute bacteria etc.the decayed remains of the plants and animals is called humus. soil is formed very slowly by the weathering of rocks,and it may even take one thousand years to form a layer of soil.the solid found at the site of their formation or origin are known as sedentary soil.others brought from elsewhere by natural agencies are called transported soil. let me also tell u bout’ the soil profile. the process Of weathering breaks up exposed rock surfaces into fine particles.thus on the top we have a layer of top-soil or horizon with the particles and mineral matter.rain water percolating through the top-soil washes down some of the finest particles of soil into the second layer,and also dissolves and washes down the soluble materials.this washing process is known as leaching.the second layer called the sub
There are four basic “ingredients” that go into the “recipe” for making soil: tiny pieces of rock, decayed plants and animals, water, and air. When small pieces of rock break off larger ones, they form the basis of all soil. This breaking can occur in several ways: through the action of glaciers pushing rocks along the ground an
