Tag: evs

A good soil needs to be deep, fine-textured, moist, free-draining, loamy, and have an organic-rich topsoil. These properties best enable plant roots to take up nutrients, water and oxygen, and get enough support for rapid growth. In clay soils with small pore spaces, water moves slowly and spreads outward from where it is applied due to capillary action. In sandy soil, irrigation water can penetrate to 72 inches below the surface within 24 hours of application. In soils with a heavy clay content, water only penetrates to roughly 36 inches in 24 hours.

Humus controls and regulates many soil functions, as well as plant growth. The better the humus count in the soil, the healthier and more productive soil will be. Regardless of the program one uses in farming operations, the higher the humus count, the better the crop is grown yield. Good humus count in the soil will hold soil moisture longer, thus less water is required for crop production. Also, good humus count reduces both water and wind erosion of soil.

(b) Top soil contains decomposed and amorphous organic matter composing of sand with humus.

Humus is the dark, organic material that forms in soil when plant and animal matter decays. It is a crucial component for soil fertility.

• A gemstone, also known as the precious stone, jewel, a gem is a piece of mineral crystal which is cut and polished and it is used to make jewellery or other accessories. Gemstones are formed from igneous rocks. Interlocking crystals grow within intrusive igneous rock and may form gemstones depending on elements present, cooling time and the environment.
  
• Hence precious stones, such as gemstones, are products of igneous rocks.
• So, the correct answer is 'Igneous rocks'.

The texture of soil is determined by the proportions of particles of different sizes. Coarse sand particles are of 0.2 to 2.00 mm in size; 0.02 to 0.2 mm particles constitute fine sand; 0.002 to 0.02 particles represent silt and particles smaller than 0.002 mm are called clay.

Inorganic matter, consisting of weathered rock particles like sand, silt, and clay, makes up the largest percentage of the soil volume.

The O-horizon is the uppermost layer of the soil profile, consisting primarily of organic material such as leaf litter and decomposed organic matter.

The A0 layer is a sub-layer of the A horizon, specifically characterized by an accumulation of organic matter in various stages of decomposition, commonly referred to as humus.