All questions of Soil Types for Primary 3 Exam

Humans

Explanation:
Fertilizers are substances that are added to the soil to provide essential nutrients that plants need to grow and thrive. The main purpose of adding fertilizers to the soil is to replenish the lost minerals.

Importance of Fertilizers:
Fertilizers play a crucial role in maintaining the fertility of the soil and ensuring healthy plant growth. They provide essential nutrients to the plants, which are necessary for their proper development. These nutrients include macronutrients such as nitrogen (N), phosphorus (P), and potassium (K), as well as micronutrients like iron (Fe), manganese (Mn), zinc (Zn), etc.

Reasons for lost minerals:
Over time, the soil naturally loses essential minerals due to various factors such as plant uptake, erosion, leaching, and weathering. When plants grow and mature, they extract nutrients from the soil, depleting its mineral content. Additionally, heavy rainfall can cause minerals to leach out of the soil, especially in sandy soils with poor water-holding capacity. Erosion can also wash away topsoil, which is rich in minerals. Furthermore, weathering of rocks and minerals in the soil can cause the release of nutrients, leading to their loss.

Role of Fertilizers:
Fertilizers are designed to replenish the lost minerals in the soil. They provide an immediate source of nutrients to the plants, ensuring their optimal growth and productivity. Fertilizers are available in different formulations, such as granular, liquid, or organic, and can be applied directly to the soil or as foliar sprays.

Types of Fertilizers:
There are two main types of fertilizers: organic and inorganic. Organic fertilizers are derived from natural sources, such as compost, manure, bone meal, and fish emulsion. They release nutrients slowly and improve the overall soil structure. Inorganic fertilizers, on the other hand, are chemically manufactured and provide nutrients in a readily available form. They can be tailored to meet specific nutrient requirements and are often used for quick nutrient supplementation.

Conclusion:
In conclusion, fertilizers are added to the soil to replenish the lost minerals. These minerals are essential for plant growth, and their depletion can lead to nutrient deficiencies and poor crop yields. By providing the necessary nutrients, fertilizers help maintain soil fertility and ensure healthy plant growth.