Soil | Class 7

Soil Profile, Properties and types are described here
You can easily understand this.
Thank you!!
Ram Charan
Follow, Like & Share

1. SOIL PROFILE, TYPES OF SOIL & PROPERTIES OF SOIL CH 9 SOIL

2. SOIL PROFILE A Vertical section through which different layers of soil are seen is called soil profile. The layers of the soil are different in colour,depth, texture and chemical composition. These layers are called horizons. A – HORIZON This Horizon Is also known as Top soil. This layer is usually dark in colour . This layer is rich in humus The roots of plants are entirely embedded in this layer SOIL PROFILE

3. SOIL PROFILE B – HORIZON This layer have more amount of minerals than humus This layer is more compact and harder than Top Soil C - HORIZON This layer is made of Lumps of rocks Plants cannot utilize this layer R – HORIZON This layer is known as bedrock This layer is full of rocks The rocks undergo weathering

4. TYPES OF SOIL The soil is classified on the basis of number of particles Types of Soils : Sandy Soil Clayey Soil Loamy Soil

5. TYPES OF SOIL LOAMY SOIL It is a mixture of Sandy and Clayey soil It has equal amount of finer and larger particles It is best for growing plants It can hold water SANDY SOIL It has more amount of large particles than fine particles It has large spaces between It cannot hold water CLAYEY SOIL It has more amount of Fine particles than larger particles Tiny gaps are there between This soil can hold water

6. PERCOLATION RATE OF SOIL The rate at which water exits from soil is called percolation rate PERCOLATION RATE = Amount of Water Percolated(mL) Time Taken to Percolate(min) Percolation rate is highest in Sandy Soil Lowest in Clayey Soil

7. ABSORBTION OF WATER BY SOIL Amount of water absorbed by soil is absorption ABSORPTION = (U-V)g

8. Questions In which layer do Bacterial & Fungi Live? In which type of Soil Percolation Rate is neither high nor low? Which type of soil is best for growing Crops? Which Soil is best for growing Rice & Wheat? Which Variable is Sandy Soil? Answer 3,4&5 from the following table X Soil 20 ml/min Y Soil 50 ml/min Z Soil 30 ml/min

9. ANSWERS TOP SOIL/A HORIZON Because HUMUS & DEAD MATTER is mostly present on this layer so, the bacteria grows here. 2. LOAMY SOIL We know that it has equal amount of Greater&Finer particles