Soil Fertility - Definition, Types and Importance (2024)

Just like humans, crops also require nutrients. Fertile soil contains all of the major nutrients required for basic plant nutrition (For example, nitrogen, phosphorus, and potassium), as well as other nutrients required in smaller amounts (For example, calcium, magnesium, sulfur, iron, zinc, copper, boron, molybdenum, nickel).

This article gives insight into what is fertile soil and its importance, the types of fertile soil, the principles of soil fertility and what are the various majors that can be taken to increase soil fertility.

Soil Fertility

Soil fertility can be defined as the ability of the soil to provide an atmosphere that is in favour of plant growth. It refers to the soil's ability to support plant growth and maximise crop yield. This can be improved by applying organic and inorganic fertilisers to the soil. Nuclear techniques provide information that improves soil fertility and crop production while reducing environmental impact.

This includes providing the plant with the essential nutrients and a suitable chemical, a physical and biological environment that enhances and promotes the growth of a plant. Fertile soil will typically have some organic matter that improves soil structure, moisture retention, and nutrient retention, as well as a pH between 6 and 7. Unfortunately, many soils lack adequate levels of all essential plant nutrients or soil conditions are unfavourable for plant uptake of certain nutrients.

Soil fertility and plant nutrition focus on the management of essential elements that are necessary for plant growth. Soil fertility directly affects the quality as well as the quantity of the crop production affecting how it can be further used for human uses. A single element is also considered essential if it is required for plant metabolism and the completion of the plant’s life cycle.

There are 17 elements that meet these criteria and are divided into macro and micronutrients. This, along with the composition of the plant, forms the biology and fertility of soils.

Types of Soil Fertility

1. Inherent or Natural Fertility:

The soil that naturally contains some nutrients and is considered fertile is known as inherent fertility. Some of the nutrients like nitrogen, phosphorus and potassium are considered essential for the normal growth and yield of the crop. These are naturally present in naturally fertile soil. The inherent fertility has a limiting factor from which fertility is not decreased.

2. Acquired Fertility:

When the fertility of the soil is developed through external agents like manures and fertilisers, tillage, irrigation etc., it is known as acquired fertility. It has been found that the yield does not increase after a point by the application of an additional quantity of fertilisers. Thus, this becomes the limiting factor of acquired fertility.

Soil Fertility and Fertilisers

Fertilisers are mixtures of nitrogen, phosphorus, and potassium compounds that promote plant growth. Fertilizers that provide all three elements are frequently referred to as NPK fertilisers, after the chemical symbols for these three elements. Inappropriate or excessive fertilisation can be harmful to the ecosystem, but it is necessary to produce adequate food for the growing population. Overuse or repeated use of fertilisers can result in an ultimate decrease in soil fertility along with acidification of the soil.

It will gradually decrease the amount of organic matter, humus and beneficial organisms in the soil which will lead to inhibiting plant development, altering soil pH, increasing pests and even releasing greenhouse gases. Fertilisers are not meant for continuous or constant use as they can result in the overall infertility of the soil in the long term. This kind of soil will not be safe to use in future for any kind of crop production.

Importance of Soil Fertility

Soil starts the chain of the food cycle wherein it feeds the plant which ultimately feeds us. They are the primary organisms of the food chain. With the improvement of soil, there will be a gradual increase in the quality of plant and crop production as well. Some of the essential aspects of soil fertility are described below:

• Soil provides direct nutrition and a foundation for plants. It is considered the most important factor in determining plant growth.

• Soil is a result of the accumulation of decomposing plant and animal matter with the ageing parent material. As this soil breaks down, these elements are released in the form of nutrients that are directly available to the growing plant.

How to Increase Soil Fertility?

There are a few ways in which one can increase soil fertility or replenish the nutrients removed from the soil. Some of these are discussed below:

1. Recycling Nutrients: This can be done by the use of plant and animal waste.

2. Use of fertilisers.

3. Through Microbial Action: This includes the use of nitrogen fixation which can be achieved through the use of grain legumes that initiates biological nitrogen fixation. This can also be done by other methods like fertilisers, green manures, etc.

4. Incorporating Cover Crops: Using cover crops can add organic matter to the soil improving soil fertility and making it healthy for plant production.

Conclusion

In this article, we have studied about natural and acquired fertility of the soil and how we can improve the soil by adding compost and rotating crops every year. A fertile soil's primary function is to provide food, which is critical in light of the FAO's Zero Hunger goal. A fertile soil also provides essential nutrients for plant growth, resulting in healthy food that contains all of the nutrients required for human health. Fertile soil is typically found in river valleys or areas where glaciers deposited minerals during the last Ice Age. Mountains are usually less fertile than valleys and plains.