(i) Soil is the upper layer of the earth composed of ________ surface material.
Ans: loose
Soil is the upper layer of the earth composed of loose surface material. Soil consists of loose particles, including minerals, organic matter, and air spaces, which collectively form the upper layer of the Earth's crust.
(ii) The mixture of minerals, plant and animal remnants, water, and air makes up the composition of ________.
Ans: soil
The mixture of minerals, plant and animal remnants, water, and air makes up the composition of soil. Soil is a complex mixture of these components, and its composition can vary widely depending on geographic location and environmental conditions.
(iii) The ability of soil to support plant growth is known as ________.
Ans: soil fertility
The ability of soil to support plant growth is known as soil fertility. Soil fertility is a measure of how well soil can provide essential nutrients and a suitable environment for plants to grow and thrive.
(iv) Alluvial soil is mainly found in the ________ and coastal plains of India.
Ans: northern
Alluvial soil is mainly found in the northern and coastal plains of India. Alluvial soil is a type of soil that is often found in river valleys and coastal regions. In India, it is particularly abundant in the northern plains and along the coastal areas.
(v) Black soil is also known as ________ soil due to its color.
Ans: lava
Black soil is also known as lava soil due to its color. Black soil, also known as Regur soil, is known for its dark color and high fertility. It is commonly found in parts of India and is excellent for agriculture.
(vi) Mountain soil is rich in ________, a natural fertilizer.
Ans: humus
Mountain soil is rich in humus, a natural fertilizer. Humus is the organic component of soil formed from the decomposition of plant and animal matter. It enriches the soil with nutrients and improves its structure.
(vii) Laterite soil is rich in ________ and aluminum.
Ans: iron
Laterite soil is rich in iron and aluminum. Laterite soil is a type of soil that is rich in iron and aluminum oxides. It is often found in tropical regions with intense weathering processes.
(viii) Desert soil is primarily found in ________ and Gujarat.
Ans: Rajasthan
Desert soil is primarily found in Rajasthan and Gujarat. Desert soil, also known as arid soil, is commonly found in arid or dry regions, and in India, it is notably present in the state of Rajasthan and parts of Gujarat.
(ix) Soil erosion is the carrying away of ________.
Ans: soil
Soil erosion is the carrying away of soil. Soil erosion is the process by which soil is removed from one location and transported to another by natural forces such as wind, water, or gravity. It can result in the loss of valuable topsoil.
(x) ________ is the practice of holding the soil in its place to prevent erosion.
Ans: Soil conservation
Soil conservation is the practice of holding the soil in its place to prevent erosion. Soil conservation techniques and practices are implemented to reduce soil erosion and maintain soil quality, ensuring its sustainability for agriculture and natural ecosystems.
(i) Which soil type is the most fertile?
(a) Red Soil
(b) Desert Soil
(c) Black Soil
(d) Laterite Soil
Ans: (c)
Black soil, also known as Regur soil, is considered one of the most fertile types of soil. It is known for its rich nutrient content, especially in terms of minerals like calcium, magnesium, and potassium. Black soil is particularly suitable for agriculture and is found in parts of India, where it supports the growth of a variety of crops.
(ii) Which soil type is rich in iron and aluminum?
(a) Alluvial Soil
(b) Red Soil
(c) Laterite Soil
(d) Mountain Soil
Ans: (c)
Laterite soil is known for its high content of iron and aluminum oxides. It is typically found in tropical regions with heavy rainfall and intense weathering processes. This soil type can appear reddish due to its iron content and is less fertile compared to some other soil types.
(iii) Which state is known for its black soil?
(a) West Bengal
(b) Maharashtra
(c) Uttar Pradesh
(d) Rajasthan
Ans: (b)
Maharashtra is known for its black soil, particularly in regions like Vidarbha and Marathwada. The black soil in Maharashtra is suitable for cotton cultivation, and the state is one of the major cotton-producing regions in India.
(iv) Desert soil is primarily found in which Indian state?
(a) Kerala
(b) Tamil Nadu
(c) Rajasthan
(d) Assam
Ans: (c)
Desert soil, also known as arid soil, is primarily found in the state of Rajasthan in India. Rajasthan has a significant arid and desert region, and the soil in these areas is often characterized by low moisture content and is not very suitable for agriculture without proper irrigation.
(v) Which activity helps in holding the soil in place and preventing erosion?
(a) Overgrazing
(b) Deforestation
(c) Plantation
(d) Soil Erosion
Ans: (c)
Plantation, or planting trees and vegetation, helps in holding the soil in place and preventing erosion. The roots of plants and trees bind the soil particles together, reducing the impact of rainfall and wind, which can otherwise lead to soil erosion. Plantation is a common soil conservation practice used to protect soil and prevent degradation.
(i) Alluvial soil is found in hilly areas.
Ans: False
Alluvial soil is not typically found in hilly areas. It is primarily formed in river valleys and plains through the deposition of sediments carried by rivers. Alluvial soil is known for its fertility and is commonly found in flat and low-lying regions rather than in hilly or mountainous areas.
(ii) Laterite soil is fertile and doesn't require any additional nutrients.
Ans: False
Laterite soil is not considered fertile in the traditional sense. While it can support some types of vegetation, it is generally not very productive for agriculture without the addition of essential nutrients. Laterite soils are often nutrient-deficient and require appropriate fertilization to support crop growth.
(iii) Red soil retains moisture well.
Ans: True
Red soil is known for its ability to retain moisture well. It has good water-holding capacity, which can be beneficial for crops, especially in regions with erratic rainfall patterns.
(iv) Desert soil supports the growth of various crops without irrigation.
Ans: False
Desert soil, also known as arid soil, is not typically suitable for supporting the growth of various crops without irrigation. Desert regions receive limited rainfall and have low soil moisture, making agriculture challenging without additional water sources. Irrigation is often necessary to cultivate crops in desert areas.
(v) Soil erosion is caused only by natural forces.
Ans: False
While natural forces such as wind, rain, and gravity are significant contributors to soil erosion, soil erosion can also be accelerated or exacerbated by human activities, including deforestation, overgrazing, improper agricultural practices, and construction activities. Human-induced erosion is a major concern, leading to soil degradation and loss of fertile topsoil.
Ans:
(i) Explain why soil erosion is a concern for agriculture and the environment.
Ans: Soil erosion leads to the loss of topsoil, affecting agricultural productivity and causing environmental degradation. It can result in reduced soil fertility, increased water runoff, and sedimentation in water bodies, leading to various problems.
(ii) Describe the characteristics of alluvial soil and its significance in Indian agriculture.
Ans: Alluvial soil is characterized by its fine sand and silt content. It is highly fertile due to its mineral-rich composition carried down by rivers from the Himalayas and other regions. It supports a wide range of crops and contributes significantly to India's agriculture.
(iii) How does black soil hold water, and what crops are suitable for cultivation in black soil?
Ans: Black soil holds water well due to its clayey nature and expansive properties. Crops like cotton, sugar cane, millet, and oilseeds thrive in black soil due to its water-holding capacity and nutrient content.
(iv) What is the primary factor responsible for the formation of red soil? Mention two Indian states where red soil is found.
Ans: The primary factor responsible for the formation of red soil is the weathering of ancient crystalline rocks. Red soil is found in states like Tamil Nadu, Karnataka, Andhra Pradesh, etc. Its lowermost layer is fertile and suitable for agriculture.
(v) Why is soil conservation important? Provide at least two methods used to prevent soil erosion.
Ans: Soil conservation is crucial to prevent soil erosion, maintain soil fertility, and sustain agriculture. Methods include afforestation, plantation, organized grazing, embankments, contour ploughing, and terrace farming. These methods prevent the loss of topsoil and maintain soil structure.
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1. What are the different types of soil found in India? |
2. Which type of soil is most suitable for agricultural activities in India? |
3. What are the characteristics of black soil? |
4. How does the type of soil affect crop cultivation? |
5. How can soil erosion be prevented? |
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