Tag: Agriculture

Introduction

Agriculture chemistry is the study of agricultural production, as well as the interaction of plants, bacteria, animals, and their environment. It is a scientific field that studies the composition of both chemistry and biochemistry. We study the production of food, Agri products, and beverages from raw materials in agriculture chemistry. Herbicides, growth regulators, fertilisers, insecticides, and pesticides are examples of agricultural materials. Agricultural chemistry seeks to increase agricultural yield, improve soil quality and fertility, and increase crop yield.

What is Agricultural Chemistry

Agriculture is the process of raising livestock, crops, and other food products. Agriculture in the modern era includes horticulture, agronomy, dairying, soil chemistry, animal husbandry, and so on. Organic, inorganic, and agricultural products are all studied in chemistry. Agricultural chemistry is the application of both agriculture and chemistry that deals with crop production and improvement. Photosynthesis, fertilisers, pesticides and insecticides, irrigation, agricultural produce storage, food processing, chemicals etc.

Why Agricultural Chemistry is important?

Chemistry plays a significant role in crop and livestock production, controlling pathogens, insects, and weeds, and improving crop yield. The world’s population is growing by the day. To meet the growing population’s demand, agricultural chemistry not only improves crop production resources but also uses crops and crop waste to produce renewable fuel and feedstocks. We know that plants produce food through the process of photosynthesis. It is a natural phenomenon, but we can learn about the mechanism involved in the photosynthesis process thanks to agricultural chemistry. This aided us in increasing crop production.

1. Agriculture chemistry contributes to soil quality improvement by testing soil and nutrients.
2. Fertilisers are organic and inorganic compounds that can be found naturally or synthetically. They are applied to the soil during agriculture to increase crop yield. Fertilisers are applied to the soil to provide the macro and micronutrients required for crop production.
3. Pesticides and insecticides are chemicals that are used in crop production to reduce damage caused by insects and pests.
4. Agriculture chemistry aids in the storage of food products, such as sulphur dioxide, which is used to keep grains fresh for long-term storage. Salicylic acid and sodium benzoate are used in food preservation and shelf life extension.
5. Modern agricultural chemistry is now using crop and food waste to produce renewable energy fuels and beverages. Examples include the production of alcohol from bagasse and the use of the Jatropha plant in the production of fuel.

Type of Material	Products
Food	Refined oil, Butter, cheese, etc.
Petroleum	Kerosene, Diesel, Petrol, etc
Construction	Mortar, glass, chemicals, and chemical compounds.
Household	Cooking gas, food process.

What is the purpose of Agricultural Chemistry?

Agricultural Chemistry’s goal is to increase crop production by using pesticides, fungicides, fertilisers, and other chemicals.  In modern chemistry, Crops and other crop wastes are used in the production of biofuels and beverages.

1. As agriculture advances, chemistry improves irrigation techniques through the use of plastic pipes, drip irrigation techniques, sprinkler systems, and so on. Crop production has increased as a result of improved irrigation and a favourable climate.
2. It has invented preservatives such as salicylic acid and sodium benzoates, as well as other chemicals, to extend the shelf life of food products.
3. Agricultural chemistry applied science improves crop quality and yield and lowers production costs.
4. A subfield of agricultural chemistry Chemurgy is working on utilising agricultural products as raw materials for subsequent production such as oil production, petroleum, cooking gas, and so on.

Summary

We learned that agricultural chemistry is a branch of science that deals with the intersection of chemistry and agriculture production. It aids in the production of agricultural products as well as the processing of food and beverages from raw materials. It establishes the relationship between the environment, microbes, plants, and animals. Furthermore, it aids in increasing the quantity and quality of food. Agriculture chemistry incorporates not only chemistry and agriculture, but also microbiology, genetics, physiology, entomology, ecology, and so on.

Frequently Asked Questions

1. Organic fertilisers: what are they?

Ans. Animal manure, fruit and vegetable compost, and fish are examples of living systems from which organic fertilisers are derived. The soil’s microbial population breaks down organic waste. It is rich in potassium, nitrogen, phosphorus, calcium, etc.

2. Inorganic fertilisers: What are they?

Ans. Minerals and synthetic chemicals are used to make inorganic fertiliser, which is synthetic. Petroleum is frequently used to produce inorganic nitrogen.

3. What do you mean by Insecticides and Pesticides?

Ans. Chemicals called pesticides are used to protect crops from things like fungi, weeds, and pests. Chemicals called insecticides are used to eradicate insects that are harmful to crops or livestock. 

Introduction

In India notably, agriculture has been practised for thousands of years without the use of artificial tools. Fertilizers that were developed in the middle of the 19th century were powerful, affordable, and easily accessible at the time, but they also had several negative side effects, such as soil erosion, water pollution, and animal body accumulation. To combat these side effects, efforts were made to find cures while simultaneously maintaining a high yield. In the 1930s, Albert Howard introduced an organic farming system to Britain by fusing his scientific techniques with traditional farming practices from India (manure, compost, and crop rotation).

What is Agriculture?

Agriculture derives from the Latin words “ager,” meaning “field,” and “colo,” meaning “to cultivate,” meaning to use or prepare a field or piece of land for producing crops. It also covers raising animals like cattle for dairy needs.

What is Organic Agriculture? 

Organic farming is the practice of cultivating crops using organic farming techniques. Compost, manure, and green manure are examples of natural fertilizers used to boost fertility and plant growth. Crop rotation is one natural or biological technique suggested to improve soil fertility. The land is allowed some time to rest after raising a crop so that it can naturally regain its fertility.

Types of Organic Agriculture

Organic agriculture is categorized into two types.

Pure organic farming:

• In this kind of organic farming, farmers only utilize natural ingredients to promote plant growth, improve soil fertility, and stop soil erosion. 
• It is best to avoid using any kind of pesticide because it hurt crops, important soil bacteria, and even people who eat the food.

Integrated organic farming:

• This method of organic farming, also known as the “Zero waste” technique, is carried out in such a way that residues or wastes are produced in “zero” proportions.

Aims of Organic Agriculture

• Protecting the environment
• Natural resource conservation
• Keeping the ecological balance 
• Improvement of soil fertility 
• Stop soil erosion 
• Protecting wildlife and plants from the negative effects of artificial fertilizers and chemicals 
• Maximizing agricultural production
• Reduce the number of chemicals we use to produce food

Practices Followed During Organic Agriculture:

• Crop rotation: To preserve soil fertility, different crops are cultivated in alternate years on the same plot of land. 
• Green manure and cover crops: Green manure improves soil fertility and is good for crop plant growth. The term “cover crops” refers to plants whose primary purpose is to prevent soil erosion, but which also progressively mix with the soil as they naturally deteriorate and serve as green manure.
• Compost and manure are made consisting of organic materials that provide nutrients for plants, such as cow dung and other crop plant wastes.
• Bio pest control: By feeding on disease-causing pests, beneficial organisms found in soil can suppress harmful pests.

Steps Involved in Developing Organic Farms

• Using organic management techniques rather than merely conventional farming methods. 
• Environmental conservation and wise use of natural resources. 
• Only natural or biological approaches, such as crop rotation, manure, compost, and cover crops, are employed instead of synthetic media that use chemicals. 
• Weeds should be pulled out since they compete with crops for nutrition and grow alongside them. 
• Pest management by biotechnology for crops. the method of organic farming that is integrated.

Disease Management

• Because infections are a major factor in plants’ decreased output, disease management is necessary. This is accomplished by keeping beneficial organisms in the soil that feed on destructive pests that degrade plants. 
• The major advantage of organic farming is that it preserves beneficial bacteria and fungi that would otherwise be eliminated by the use of conventional fertilizers and pesticides through a system of “checks and balances.” 
• These microbes aid in preserving the soil’s ecosystem and inhibit the development of pathogenic bacteria and fungi.

Methods of Organic Agriculture: 

• Weed management: Organic farming attempts to lessen the presence of weeds rather than eradicate it.
• Biological pest control: Beneficial microbes that are retained and not permanently destroyed keep harmful disease-causing microbes in check.
• Soil Management: As the most crucial factor in plant growth, soil management involves a variety of techniques. Cover crops, manure, compost, and the maintenance of beneficial organisms are among the measures used to increase its fertility.
• Polyculture: To quickly meet the need for food, many different types of crops are grown at the same time.
• Manure and compost: To increase output while causing the least amount of damage to the soil and plants, organic materials such as plant and animal waste are utilized to create natural fertilizers.

What are the Benefits of Organic Agriculture? 

• Environmental protection is facilitated by reducing chemical use and the pollution that results from it. 
• Since no toxic pesticides are applied, it protects non-target creatures, including people and animals, whose health is impacted when these chemicals build up in their systems. 
• Because organic farming uses naturally produced manure, the high cost of pesticides is reduced. 
• It helps to lessen erosion while also enhancing the soil’s physical attributes including fertility and water-holding capacity.
• Additionally, crop failure risk is decreased.

Disadvantages of Organic Agriculture

• It’s hard to find organic manure in large quantities. 
• Even though ordinary Indian farmers’ agricultural methods are organic, they are not recognized as such and are nonetheless sold for the same prices as conventional (normal) farming produce. 
• A regular farmer cannot understand the regulations of organic farming, which include production, processing, transportation, and crucial certification. 
• Farmers don’t like certification since it is an expensive process that necessitates a lot of paperwork. 
• Since organic farming uses special techniques, its products are typically more expensive for customers.

Frequently Asked Questions

1. Is organic farming a new or traditional practice in India??
Ans. Since the beginning, only natural methods have been utilized in India. Artificial methods only began to be used in the 19th century, but as soon as people realized the problems they brought, they quickly returned to favouring organic farming, not just in India but also in other foreign nations.

2. How is organic farming doing in India?
Ans. In India, there is a beginning of organic farming; just 2% of the land is used for organic farming; the remainder is used for conventional farming using synthetic chemicals. By 2030, this will be more successful.

3. What are the main advantages of organic farming over conventional agriculture?
Ans. Preventing soil erosion has several positive effects, including higher soil fertility, better growth conditions, and reduced water contamination. This is a significant issue with conventional farming.

4. What benefits do conventional farming techniques have over organic ones?
Ans. Advantages of Conventional farming: The plants created all have the same genetic makeup. Using this technique, plenty of plants can be grown swiftly. While some plants generate few or no seeds, others do not allow their seeds to germinate.

Introduction

In the farming and agricultural sectors, the tools used to streamline the process are referred to as agricultural implements. To create a productive and helpful environment, agricultural operations today require a different range of tools, such as drills, diggers, furrows, sickles, and so on. Without the use of the implements that are supposed to finish these processes, the current situation in agriculture demonstrates development. In this tutorial, we’ll discuss agricultural equipment and how they affect the farming and agricultural industries.

What is Agriculture?

Agriculture is the activity of growing crops and rearing animals that supports human sedentary behavior and the growth of sustenance. It may be involved in the production, processing, and distribution of agricultural products. For most rural communities, it serves as their primary source of income. In metropolitan regions, individuals are provided with vegetables and grains for food.

Significance of Agriculture

• The majority of the world’s food supply comes from agriculture, which also guarantees the population’s access to food and nourishment. 
• Since agriculture contributes over 20% of GDP (Gross Domestic Product), it is regarded as the main source of income for the nation. 
• A large number of people have employment opportunities in agriculture. 
• It plays a significant part in the export of significant goods on a global scale and in balancing a nation’s crucial expenditures while preserving its foreign currency. 
• Additionally, it generates fibers, raw materials, and biofuels.
• Utilizing the production and selling of agricultural goods eliminates poverty in rural regions. 
• Selling the by-products of raising animals brings considerable profit for farmers.

What are Agricultural Implements?

Agriculture implements and farming equipment are tools or pieces of machinery used to complete tasks quickly. These are used in agriculture to lessen physical labor and increase crop output. Early farmers developed their own labor and time-intensive tools, which were difficult to use. After modernization, cutting-edge processes and tools have taken the place of outdated ones.

To make work easier, a variety of agricultural implements are used in agriculture. The following is a list of important agricultural tools: 

• Planting tools 
• Harvesting equipment
• Irrigation equipment
• Tools for cultivating soil

Types of Agricultural Implements

Farmers employ a variety of agricultural instruments to increase crop yield. It includes the following:

Soil cultivation implements

• The cultivation of the soil is a crucial stage because it enables crop roots to enter the soil and absorb nutrients and water. 
• Soil preparation is done with basic equipment like a hoe, a plow, and cultivators. 
• The land is plowed and made ready for cultivation with the use of spike, drag, and disc harrows.

Irrigation machines

It is made up of a pump that draws water from the bottom and a pivot irrigation system that supplies the crops with the right amount of water.

Planting machines

• The plant is protected from animals and birds attack by the use of a seed drill, which provides a deep and proper area for planting. 
• It enables the plants to receive enough sunlight, nutrients, and water. 
• After crop cultivation, a large area is seeded using tools including air seeders, broadcast seeders, transplanting implements, and more.

Harvesting implements

• Cutting fully developed and ripe crops is the procedure of harvesting. 
• Crops are harvested using harvesting equipment like pickers, trailers, and diggers.

Division of Crops

The agricultural process develops food grains for human consumption and utilizes their raw materials for industrial use. Crops are cultivated according to the type of soil and weather conditions. There are three major divisions of crops. 

Kharif crop

• In the monsoon season, the seedlings of crops begin to grow and are harvested in the autumn.
• A warm climate and excess water are necessary for its growth.

Rabi crop

• In humid conditions, seeds germinate and develop well, and crops grow well. 

Zaid crop

• During the period between Kharif and Rabi, the Zaid crop develops.
• For blooming flowers, warm, dry weather is required for crop growth.

Type of crop	Season	Examples
Kharif crop	September to October	Millets. maize, rice, soybean, cotton
Rabi crop	October to December and April to May	Barley, oats, mustard, wheat, peas
Zaid crop	March to June	Watermelon, cucumber, muskmelon, pumpkin, pulses

Categories of Crops

Depending on their use, crops can be classified into two types.

• Food crops: Food crops are mainly grown for human and animal consumption. There are several major food crops, such as vegetables, oilseeds such as sunflower, groundnut, sesame, and cereals like paddy, wheat, and fruits.
• Cash crops: Crops that are grown to generate income rather than for domestic consumption are called cash crops. Rubber, tea, coffee, jute, spices like mustard, chili, turmeric, garlic, coriander, and some medicinal crops are some of the most important cash crops.

Summary

Agriculture implements and farming equipment are tools or pieces of machinery used to complete tasks quickly. Farmers employ a variety of agricultural instruments to increase crop yield.  The agricultural process develops food grains for human consumption and utilizes their raw materials for industrial use. Depending on their use, crops can be classified into two types such as food crops and cash crops.

Frequently Asked Questions

1. How does agriculture have such a big impact on a nation?
Ans. A nation’s economy is based on agriculture because it provides food, is a source of commercial products, creates employment, and eliminates poverty. More than half of the population solely depends on agriculture for a living.

2. Why are outdated agricultural equipment and practises replaced?
Ans. In addition to hand-made tools, traditional techniques are tedious and time-consuming. Therefore, advanced techniques and equipment are used to increase crop production quickly. 

3. What farming tools are used to get the soil ready for cultivation?
Ans. Disc harrows, drags, and hoes are agricultural implements used to plow the soil, allowing roots to penetrate the ground and absorb moisture and nutrients more easily.

4. What kinds of crops are grown during the monsoon and summer seasons?
Ans. Kharif crops are produced in the monsoon season of September and October. Zaid crops are produced in the summer season, from March to June. Rabi crops are also produced in the summer, from April to May.

5. What are the main tools used in agriculture?
Ans. Machines for planting, harvesting, irrigating, and cultivating the soil are the most important agricultural implements. The use of these is widespread in organic farming and commercial agriculture.

Introduction

The discovery of iron led to a revolution in Indian agriculture. By the end of the Chalcolithic Age, the Indian subcontinent had been using iron for around 2500–3000 years. Now, during this time, the tools made of iron and steel were stronger and more efficient than those made of bronze. Manufacturing iron tools enhanced farming and contributed to a bigger economy.

The creation of iron farming implements greatly facilitated the agricultural process and contributed to a larger increase in farm produce. People were able to adapt to a stable existence at that time through commercial farming (trade between other nations) and subsistence farming, which helped people produce in huge amounts. Iron implements contributed to the prosperity of tiny kingdoms in a similar manner.

Indian Iron History from a Historical Perspective

In India, evidence of iron tools has been found in megalithic (big stone) burial sites. These sites in India comprised modern-day Karnataka and Kerala in the south, extended to some parts of central India and trans-Vindhyas. In many of these sites, the use of iron perhaps started by the end of the Neolithic and during the Chalcolithic age. 

Our Rig Veda and Yajur Veda contain references to the process of obtaining metal from ores. Iron was the third metal mentioned in Rig Vedic hymns, after gold and silver. Iron utilisation saw rapid development around 1400 BCE. Early evidence of iron smelting was thought to have been produced by tribal craftspeople in several places. 

Agriculture and the Iron

Agriculture underwent a turning point with the invention of iron. People have now begun to create powerful, long-lasting, and simple-to-form tools and weapons with this metal. 

This allowed them to create a compact, extremely sharp, and lightweight instrument that was challenging to craft out of stone or copper. Sickles, axes, spades, and plough shares are a few examples of significant tools. They could now plough difficult land thanks to these.

As agricultural output increased, people started to stay put in one location for longer periods of time, as opposed to moving around in search of food and water. The size of kingdoms also grew as a result. 

The king was now in need of money or taxes from the population to maintain his country. Farmers became the principal taxpayers because agriculture was one of the kingdom’s most productive industries. The monarchs used to encourage farmers by making arrangements for canals, wells, and tanks to boost farm output to increase the revenue from this field.

Iron Tools

The use of iron tools fundamentally altered human life. A new type of permanent community emerged with the large-scale production of tools. The provision of military equipment like iron swords and other weapons that were utilised by armies and soldiers for fighting wars and conflicts, not only changed agriculture but also established the groundwork for large kingdoms and empires. Since the idea of communities had begun to take hold, individuals had started to build their spheres of influence.

People, now, began establishing ties with other nations as well. The development of agriculture and the subsequent creation of surplus grain opened the door for thriving trades. Tools were traded for grain, which resulted in the growth of trade customs. Over time, as trade increased, coins started to be used in transactions. Numerous Roman coins have been discovered by archaeologists in India.

Summary

The discovery of iron altered the course of history. Its discovery was unexpected, but its expansion took centuries. The tribals of India carried the traditions from antiquity to the modern era. When the famous Damascus sword was being prepared with indigenous steel-making technology, India was the workshop of the entire world. The invention of the iron in some ways created the groundwork for a civilization that was more civilised. However, as with any historical event, there were ups and downs in India’s iron history due to a variety of internal and external factors.

Frequently Asked Questions (FAQs)

1.How did Early Humans Discover Iron and use it for Tools?
Ans: Humans had figured out how to extract iron from rocks and turn them into implements made of iron. Iron was first discovered in rocks, or iron ore, which was melted at extremely high temperatures. The iron was heated and hammered while in contact with charcoal, resulting in the iron being stronger and more durable.

2.What Effects did the Iron Age have on Human Life?
Ans: The development of iron tools aided in making farming easier and more efficient. Farmers could plough tougher soil, allowing them to harvest new crops and free up time for more leisure activities. Throughout the Iron Age, new crop and livestock varieties were introduced at various times.

3. How did Early People’s lives Alter between the Bronze and Iron Ages?
Ans: Around 1200 BCE was the start of the Bronze Age. Tools from this era were constructed of bronze. Iron, which was more durable and powerful than bronze and so brought about the Iron Age, soon took its place.

Introduction

Agriculture has played a significant role in the rise of human civilization, but organic farming of domesticated species has produced food surpluses that have enabled people to live in urban areas. Agriculture is the art and science of creating and cultivating soil, increasing yields, and keeping animals. Agriculture and farming have historically been essential to human life. The expansion of agriculture and farming was a factor in the development of civilization.

What is Agriculture? 

Agriculture is characterized as the practice of growing plants and animals for human consumption. Various parameters need to be considered in agriculture, such as the type of crop, soil characteristics, environment, and so forth. Farmers decide which crop should be cultivated at what time and location based on these parameters. Aside from that, reasonable soil, environment, and season are insufficient to produce a high-quality product. It necessitates several tactics that need to have been used.

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Importance of Agriculture

Social and Economical Aspect:

• Agriculture increases the availability of food, which improves population nutrition and promotes population health. 
• A small number of people cannot do agriculture. Each of its processes requires the input of numerous persons. Consequently, this results in the creation of jobs.

Environmental Aspect:

• Waste management depends heavily on agriculture. The biodegradable wastes can be transformed into manure, which the plants can use as a source of food.
• With the right treatment, bare soil can be turned into crops, ensuring agriculture’s efficient use of land resources. 
• It significantly contributes to preserving the microclimate of any location and raises the standard of the ecosystem as a whole.

What are the Basic Agricultural Practices?

Those consecutive actions that are taken to guarantee the proper production of crops are referred to as “agricultural practices.” To guarantee a yield of great quality, this must be done. The next section has a quick discussion of the steps.

Steps of Agricultural Practices

• Preparation of soil:
• • It is crucial to prepare the soil to make sure it is rich, well-drained, well-aerated, uniform, and can hold enough moisture. This stage is essential because the soil must survive numerous adverse situations. After all, it is exposed to them. 
  • Typically, the preparation is carried out with the aid of various tools, such as a hoe and a plow.
  • To provide the best aeration, the soil must be dug out and loosened.
  • To spread the dirt equally and avoid lumping, leveling is done after plowing. 
  • Finally, there is a chance that the soil has run out of nutrients, which could be bad for plant growth. Manure and fertilizers are thus applied to restore it.
• Seed selection and sowing

• Choosing the right seeds is crucial to getting a good crop. 
• A quality seed, also known as an HYV or High Yielding Variety seed, guarantees improved plant growth, increased disease resistance, and increased yield. 
• The chosen seeds must be planted in the prepared field after being chosen. 
• Sowing is the distribution and burying of seeds into the soil, whether by hand or with the aid of machines.
  
• Irrigation
• To meet the crops’ water needs, the best possible amount of water is applied to the soil where the crops are growing. 
• A source of water, such as ponds, wells, rivers, etc., is typically supplied by a variety of channels, such as canals or pipelines.
• Crop maintenance
• • Considering that the crops must grow for a long period and are exposed to the elements, they need some maintenance. 
  • In essence, they can be destroyed by the numerous pests, birds, rodents, etc. that are likely to attack them.
  • Unwanted plants known as weeds can encroach on cropland and compete with crops for nutrients, stifling the development of crops. 
  • To protect them, it is therefore imperative to apply weedicides, insecticides, etc. 
  • To stop bird assaults, farmers frequently construct scarecrows.
• Harvesting
• • It is the process of gathering the crop’s valuable components, and it is typically carried out after the crop is fully mature and has reached its ideal development stage. 
  • It can be carried out manually with implements like a sickle or with the aid of machines.
• Storage

• In this last step, the harvested goods are moved to the granaries or storehouses before being distributed to the market. 
• To prevent desiccation, it is essential to dry the items before storing them, especially grains and pulses.
• The items are additionally fumigated to deter rodent and pest infestations.

What are Sustainable Agricultural Practices?

The concept of sustainability is the prevention of resource depletion by the adoption of specific actions that preserve both the health of the natural world and the future of humanity. Some of the measures taken in agriculture are discussed below.

• Making sure that soil is properly used and prepared to prevent erosion.
• Reducing water use through the application of new methods and tools.
• Drop-by-drop watering is done with drip irrigation, which is time-controlled. In the revolutionary practice of hydroponics, nutrients are dissolved in water and fed to plants to provide them with nutrition.
• The use of biodynamic farming methods is recommended.
• Crop rotation proposes that different crop types should grow in a specific region.
• Promoting the expansion of the pests’ natural predators to reduce the need for pesticides, weedicides, and other chemicals.

Summary

Agriculture is characterized as the practice of growing plants and animals for human consumption. Agriculture increases the availability of food, which improves population nutrition and promotes population health. The biodegradable wastes can be transformed into manure, which the plants can use as a source of food. It is crucial to prepare the soil to make sure it is rich, well-drained, well-aerated, uniform, and can hold enough moisture.  Crop rotation proposes that different crop types should grow in a specific region.

Frequently Asked Questions 

1. Define Pesticides?
Ans. Pesticides are a class of chemicals that include insecticides, herbicides, and fungicides that are used to control pests (harmful organisms) in agriculture. Examples include glyphosate, DDT, etc.

2. Why is it no Longer Advisable to use Fertilizers Today?
Ans. Fertilizers are extremely damaging to the environment. Overuse of fertilizers creates contaminants that travel via the water and air. They obliterate the water and soil microorganisms. They contribute to a phenomenon known as “biomagnification.” So it is not recommended to use more fertilizers.

3. Which Crop Diseases are Prevalent?
Ans. Common bacterial diseases include fire blight, necrosis, and Granville withering. Exfoliation, wheat black rust, and other common fungi-caused illnesses are only a few examples.

 4. What is the Indian “Green Revolution”?
Ans. With the use of technology, agricultural systems in India were transformed into modern industrial systems during the Green Revolution of the 1960s. This period included the use of HYV, mechanized farming tools, irrigation systems, fertilizers, and pesticides.

5. Define Genetically Modified Crops?
Ans. Genetically modified crops are those whose genomes have undergone genetic engineering modifications to exhibit desired features like higher nutrient production and pest resistance. For example, BT brinjal.

Introduction

A dam is a physical structure that slows or restricts the flow of subsurface or surface water. Dams build reservoirs that serve multiple purposes, including flood control, irrigation, human consumption, industrial use, aquaculture, and navigability. Although they are more frequently erected on rivers, dams can be constructed anywhere. They may also be built on streams and estuaries.

What is a Dam?

A dam is a sizable, barrier-like structure that is erected across a body of flowing water. Water is held back and stored for later use because of construction. A reservoir is a term used to describe the vast amount of water storage created on the upstream side of a river when it is prevented from flowing by a barrier. Floodgates on dams can be opened or closed to allow only a small flow for human use.

During floods, gates also enable the release of extra water from the reservoir side. A surplus of water collects on the reservoir side of a river when it floods. To let surplus water out, the floodgates are slowly opened. Dams are primarily built for this reason.

For more help, you can Refer to lesson 16 – Water in Science Class 7. Checkout the video Lesson for a better understanding

Uses of Dams

• Irrigation: In recent years, irrigation for crops has primarily been provided by dams. Rainfall in tropical nations like India is only experienced for a portion of the year. However, agriculture is a year-round industry that uses water for growth, depending on the stage of growth. While others, like rice and sugarcane, require excessive amounts of water. Agriculture was made possible by irrigation, even in remote areas with low subterranean water levels.
• Electricity: The floodgates are opened, allowing the reservoir’s water which is already under high pressure to pass through the turbine that powers the generator. A turbine transforms the kinetic energy of water into mechanical energy, which is then transformed into electrical energy by a generator.
• Reservoirs are a great place for recreation. Many reservoirs provide the local people with camping, boating, and fishing facilities.

Advantages of Dams

• Hydroelectric power, which is produced by dams, is independent of all fossil fuels. As a result, hydroelectricity is a source of energy that is constantly replenishing and can be used. With a growing population comes a rising need for energy. One of the safest methods to address the energy situation is using hydroelectric electricity.
• A reservoir maintains a sizable water reserve that is mostly used to store fresh water that can be used later in times of water scarcity.
• You can irrigate with the reservoir water. Crop plants can be effectively watered across long distances. Food is produced on the irrigated farmlands. Demands for drinking water are alarmingly rising along with population growth.
• Floods are prevented by dams, which redirect water flow. Numerous lives are saved every time water is slowly released from reservoirs through floodgates, and property damage is also avoided. 
• A reservoir is a gathering place for many aquatic animals, including fish and turtles. When dams are built, a river that is already flowing becomes a lake. It becomes a lake environment when freshwater fish and turtle species seize the opportunity to multiply.

Disadvantages of Dams

• To create a sturdy basement and reservoir, large layers of dirt must be dug out during the dam’s construction. The earth’s topography is harmed by this. Because of this, earthquakes happen more frequently. However, effective engineering, design, and planning can stop such destruction. 
• Dams are substantial, concrete buildings. They are not built economically. 
• Dam construction necessitates a vast area. It is necessary to move the local farmers and residents to the area. Their social and economic lives are affected, and there are long-term repercussions.
• In addition to displacing people, the natural habitat is also greatly disturbed. Concerns about the flora impacted by dam construction are mostly focused on deforestation and the loss of agriculturally productive land. 
• Natural wildlife that lives in the dam region is also out of control and occasionally even poses a threat to its population. To maintain their populations, breeding grounds and nesting locations are crucial. When other factors perturb these areas, their population changes. 
• Bird species are disturbed, in addition to terrestrial and aquatic species. 
• Fish living in freshwaters are the primary food source for migratory birds that nest on riverbanks. 
• Migratory birds lose their feed and are prevented from reproducing as they do throughout the year due to the drastic shift in aquatic life caused by dam building.
• The groundwater table in the surrounding areas is decreased as a result of deepening the riverbed to create reservoirs. This has a significant negative influence on nearby, naturally occurring vegetation.

Summary

A dam is a physical obstruction that slows or restricts the flow of subsurface or surface water. Floodgates on dams can be opened or closed to allow only a small flow for human use. In recent years, irrigation for crops has primarily been provided by dams.  A reservoir maintains a sizable water reserve that is mostly used to store fresh water that can be used later in times of water scarcity. Dams are substantial, concrete buildings. They are not built economically.

Frequently Asked Questions 

1. Do Dams Last Forever?
Ans. A dam may be built in around ten years, and its lifespan is about one hundred years. Certain mechanical components, including motors and gates, need to be changed after a dam has been in place for 50 years. However, operational dams will undergo routine inspections. When necessary, all repairs and maintenance will be carried out right away.

2. Can we Rely Solely on Hydroelectricity to Provide our Electricity?
Ans. A renewable energy source is a hydroelectricity. Since the dam-related operation does not disrupt the water cycle, the claim that water will not run out is valid. The problem is that rivers and streams are the only sources of flowing water that dams may use. Hydroelectric power cannot be the only source of sustainably produced energy.

3. What Connection does a Dam have to Greenhouse Gases?
Ans. Large expanses of vegetation are flooded when a dam is built, submerging numerous trees. Low oxygen levels can be found near the bottom of stagnant waters in reservoirs. The reservoir’s lower layers, which are abundant in biomass, effectively release methane into the atmosphere as it breaks down.

4. What Advantages do Dams Offer to Farmers?
Ans. Large amounts of water are stored in reservoirs where they can be irrigated for use in agriculture. Croplands can also be effectively irrigated in semiarid areas far from the riverbed. Rainfall is not necessary for farmers to be able to cultivate.