Tag: biology

The soil needs to be aerated and watered properly to allow proper growth and development of the plants. When the plants are watered frequently or the water is not drained properly, then the water logging takes place. Due to the accumulation of the water in the soil, the oxygen cannot enter into the soil and in the roots of the plants. This results in the death of the plants. 

Intensive agriculture is the commercial agriculture where chemical pesticides and fertilizers are used to increase the crop production for more earning. By the use of the chemical in large amount soil fertility gets reduced. Thus, the correct answer is option D.

Fertility of the soil is not only decided by its ability to hold water or organic materials or its ability to retain nutrients but it is decided by all the factors combined and how well can it support life. If a soil has a huge thriving of plants, microorganism, etc with the availability of adequate resources then it is considered as very fertile soil.

Soil pH is important because it influences several soil factors affecting plant growth, such as (1) soil bacteria, (2) nutrient leaching, (3) nutrient availability, (4) toxic elements, and (5) soil structure. Bacterial activity that releases nitrogen from organic matter and certain fertilizers is particularly affected by soil pH, because bacteria operate best in the pH range of 5.5 to 7.0. Plant nutrients leach out of soils with a pH below 5.0 much more rapidly than from soils with values between 5.0 and 7.0. Plant nutrients are generally most available to plants in the pH range 5.5 to 6.5. Aluminum may become toxic to plant growth in certain soils with a pH below 5.0. The structure of the soil, especially of clay, is affected by pH. In the optimum pH range (5.5 to 7.0) clay soils are granular and are easily worked, whereas if the soil pH is either extremely acid or extremely alkaline, clays tend to become sticky and hard to cultivate