1.5. Adding Manure and Fertilisers

The substances which are added to the soil in the form of nutrients for the healthy growth of plants are called manure and fertilisers.

In agriculture, farmers need to ensure that the soil is rich in nutrients to support plant growth. Manure and fertilisers are two main substances used to increase the nutrient content of the soil. Manure is often made from organic materials like decomposed plant or animal waste, while fertilisers are typically chemical compounds that provide specific nutrients.

Think of manure and fertilisers like vitamins and minerals for plants. Just like we take supplements to ensure we have the right nutrients for our health, plants also need added nutrients from these substances to grow strong and healthy.

Soil supplies mineral nutrients to the crop plants. These nutrients are essential for the growth of plants. In certain areas, farmers grow crop after crop in the same field. The field is never left uncultivated or fallow. Imagine what happens to the nutrients?

Soil provides essential minerals that help plants develop properly. However, if the same crops are planted repeatedly without allowing the soil to rest (a process called fallowing), the soil can become depleted of these nutrients, leading to weaker plants. To combat this, farmers need to enrich the soil again by adding manure or fertilisers.

Imagine a garden where the same flowers are planted year after year without changing the soil. After a while, the flowers wouldn't bloom as beautifully because the soil has lost its nutrients. That’s why it’s important to 'feed' the garden with compost or fertilizers, just like how we need new nutrients in our diet to stay healthy.

Therefore, farmers have to add manure to the fields to replenish the soil with nutrients. This process is called manuring. Improper or insufficient manuring results in weak plants.

Manuring is the process of adding organic matter to the soil to replenish its nutrients. This is critical for maintaining the health of crops, as insufficient nutrients can lead to poorly developed plants that yield less produce. Farmers must apply the right amounts of manure to ensure the soil remains fertile and supports crop growth.

Think of manuring like regularly feeding your pet. If you don’t provide them with enough food, they don’t grow strong and may get sick. Similarly, if farmers do not add enough manure to their fields, the crops will not thrive.

Manure is an organic substance obtained from the decomposition of plant or animal wastes. Farmers dump plant and animal waste in pits at open places and allow it to decompose. The decomposition is caused by some microorganisms. The decomposed matter is used as organic manure. You have already learnt about vermicomposting in Class VI.

Manure is created through the natural process of decomposition, where microorganisms break down organic materials like plant residue and animal dung. This not only recycles waste but also creates a nutrient-rich substance that improves soil quality. Vermicomposting is a method of generating manure using worms, which helps speed up the decomposition process.

Consider a compost bin in a backyard. When you throw in vegetable scraps and yard waste, over time, those scraps break down and create a rich soil amendment. This is similar to how manure is produced on farms, converting waste into something valuable for plant growth.

Fertilisers are chemicals which are rich in a particular nutrient. How are they different from manure? Fertilisers are produced in factories. Some examples of fertilisers are — urea, ammonium sulphate, super phosphate, potash, NPK (Nitrogen, Phosphorus, Potassium).

Fertilisers are synthetic products specifically designed to contain high concentrations of nutrients necessary for plant growth. Unlike manure, which is organic and can improve soil structure, fertilisers usually provide targeted nutrient support but do not enhance the soil's structure or microbial life significantly.

Think of fertilisers like a multivitamin pill for plants. These pills pack a concentrated dose of essential nutrients that plants need to flourish quickly, similar to how we might take vitamins to boost our health when we're not getting enough from food.

The use of fertilisers has helped farmers to get better yield of crops such as wheat, paddy and maize. But excessive use of fertilisers has made the soil less fertile. Fertilisers have also become a source of water pollution.

Using fertilisers can significantly increase crop yields, making farming more productive. However, over-reliance on these chemical inputs can lead to soil degradation over time. Excess nutrients can leach into waterways, causing pollution and issues like algal blooms, which can harm aquatic ecosystems.

Imagine if someone took too many vitamins every day, thinking it would make them super healthy. Instead, it could lead to health problems. Similarly, while fertilisers can help crops grow, too much can damage the quality of the soil and surrounding water sources.

Therefore, in order to maintain the fertility of the soil, we have to substitute fertilisers with organic manure or leave the field uncultivated (fallow) in between two crops. The use of manure improves soil texture as well as its water retaining capacity. It replenishes the soil with nutrients.

To promote a sustainable agricultural practice, farmers are encouraged to integrate organic manure to keep soil healthy. Allowing fields to rest (fallow) between crops helps restore soil nutrients naturally, enhancing its structure and moisture retention. This leads to a healthier ecosystem overall.

It’s similar to giving a person a break after working hard for a long time – they need time to recover and regain their energy. By allowing fields to rest, farmers help the soil recharge and recover its nutrients instead of exhausting them continuously.

Another method of replenishing the soil with nutrients is through crop rotation. This can be done by growing different crops alternately. Earlier, farmers in northern India used to grow legumes as fodder in one season and wheat in the next season. This helped in the replenishment of the soil with nitrogen.

Crop rotation involves planting different types of crops in the same area in sequenced seasons. This method works because different crops have varying nutrient needs and some, like legumes, can fix nitrogen in the soil, improving its fertility for future crops.

Think of crop rotation like having a balanced diet. Just as too much of one food isn’t good for your health, focusing on one crop year after year can deplete specific nutrients from the soil. Having a variety of crops keeps the soil healthy and nourished, creating a better environment for growth.

Farmers are being encouraged to adopt this practice. In the previous classes, you have learnt about Rhizobium bacteria. These are present in the nodules of roots of leguminous plants. They fix atmospheric nitrogen.

Rhizobium bacteria play an essential role in enriching soil health by fixing nitrogen from the atmosphere in a form that plants can use. This is particularly important in crop rotations that include legumes, as these plants help maintain soil fertility.

Imagine Rhizobium bacteria as tiny superheroes for the soil. They take nitrogen, which plants usually can’t use directly from the air, and transform it into a nutrient that plants can absorb. This way, crops like beans or peas help 'charge up' the soil for future planting.

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