Tag: soil properties

Plants grow best in neutral or slightly acidic pH. Slight acidity favours tree growth and forms forests. Slight alkalinity is however, helpful in growth of grasslands and some crop plants like legumes. Hence, for most plants a pH value of 6 to 7 is favourable.

Soil salinity is determined by measuring the electrical conductivity of a soil-water extract. A conductivity meter is the standard instrument for this measurement.

• Lime is a valuable soil amendment that helps plants and lawns flourish by raising soil pH.
• Most vegetables grow best in a slightly acidic to neutral soil, with a pH between 6.0 and 7.0 hence acidic soils having low pH is added with lime for raising its pH.
  
• Hence Lime is added to soil which is acidic.
• So, the correct answer is 'Lime'.

Soil salinity in arid regions is primarily caused by the accumulation of soluble salts near the surface due to high evaporation rates exceeding precipitation. This prevents salts from being leached away.

Petroleum products are used as transportation fuels, fuel oils, for generation of electricity, road oils etc. major use of  petroleum is in transport.

Pedology refers to study of soil in their natural environment. Demography refers to study of human population. Paleontology refers to the study of fossils. Hydrology refers to the study of water.

• When a plant's soil pH increases the plant's ability to absorb certain nutrients is disrupted.
• A pH of 6.0 to 7.0 (slightly acidic to neutral) range is most suitable for the best growth of plants. 
  
• A most economical and effective method to control the pH of the soil is the addition of $CaCO _3$ because it increases the pH level of acidic soil, thus reducing the acidity and increasing the alkalinity of the soil.
  
• Hence the most economical and effective method to control the pH of the soil is $CaCO _3$.
• So, the correct answer is '$CaCO _3$'.

• The water holding capacity of a soil is a very important agronomical  characteristic. 
• small particles have a much larger surface area than the larger sand particles.
  
• large surface area of particle allows the soil to hold a greater quantity of water. so , option A is correct.