Science 1 Marks Question

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.

When dry soil is added in the water in a glass and stir it, bubbles appear. These bubbles are caused due to the air present in between the soil particles.

Clearing or Removal of forests or stands of trees.

The nature of any soil depends upon the rocks from which it has been formed and the type of vegetation that grows in it.

Loamy soil is the most fertile soil and used for growing crops.

Red and yellow soils are found in areas, which receive low rainfall. They contain huge concentration of iron oxides that are responsible for giving the reddish or yellow colour.

Polythene bags, plastics, waste products, chemicals and pesticides.

The loamy soil has large amount of humus mixed in it. It has the right water holding capacity for the growth of plants. So loamy soil is known as best for growing plants.

The soil particles with the increasing order of their particle sizes can be shown as: Clay < Silt < Sand < Gravel < Rock

The soil has been categorised into four major groups, i.e.

• Clay.
• Silt.
• Sand.
• Gravel.

Disintegration of parent rocks by some physical, chemical and biological agents is called weathering.

A-horizon

Sandy soil, Clay soil and Loamy soil.

Manures.

The components of loamy soil are Sand, Slit and Clay.

Because it is rich in humus and minerals.

They both reduce the size of a rock body.

Clay soil.

Areas of little or no surface vegetation, such as deserts and barren lands.

Soil.

A vertical section through different layers of the soil is called the soil profile.

No, soil from a field cannot be used to make toys. In order to make toys, the soil should be clayey.

Earthworms are called a farmer’s friend because they make the land fertile by moving in soil when the land is watered, eating the soil and defecting in it.

Weathering.

Polythene bags and plastics pollute the soil as they kill the organisms living in the soil. That’s why, it is necessary to ban the use of polythene bags and plastics.

Clayey soil.

Yes.

Percolation rate of water is highest in the sandy soil, while the lowest in the clayey soil.

Soil is the crust part of the earth. It is mainly the mixture of rock particles and humus.

The organic matter of the soil formed by decaying remains of plants and animals that enriches the soil is called humus.

It is made of a relatively high proportion of fine particles.

The substances which pollute the soil are polythene bags, plastics, waste products, chemicals, pesticides, etc.

Clayey soil is used to make matkas and surahis.

Clayey soil and loamy soil are rich in humus and are suitable for growing plants like wheat and gram.

No, it is because different types of soil has different absorbing capacity of water.

The two major components of soil are weathered rock particles, i.e. non-living components and humus that consists of living organisms like fungi, bacteria, worm, insects, etc.

Clayey soil.

Soil erosion is defined as the removal of the topsoil. The different agents responsible for soil erosion are wind and water.

Soil is the crust part of the earth. It is mainly the mixture of rock particles and humus. Wind, rainfall, temperature, light and humidity are the factors which affect the soil profile and bring changes in the soil structure.

Sandy soils are light, well aerated and dry.

For planting paddy (rice), clayey soil that is rich in organic matter and have a good water retaining capacity is ideal.

Sandy soil.

The absorption percentage of water can be calculated by the formula given below.

Humus is formed by decaying remains of plants and animals which are only found in topsoil.