Loose material which forms the thin surface layer of the Earth. | Soil |
What is soil a mixture of? | Inorganic matter and minerals and humus |
What is soil a result of? | weathering and disintegration of rocks |
Is soil a renewable resource? | yes |
What is the process of soil formation called? | Pedogenesis |
How is silica present in the sand? | in the form of small crystalline grains |
What is the main constituent of sand? | Silica |
How is silica derived? | disintegration of rocks |
What is a mixture of silicates and minerals such as iron,calcium,sodium,potassium and aluminium? | Clay |
Which inorganic compound of soil retains moisture? | Clayey soil |
What is chalk? | Calcium carbonate |
What is the most essential element for plant growth? | Calcium |
What components of soil determine the fertility of soil? | Organic components |
What is the ultimate form of mineral? | Humus |
Is humus a mineral? | Nooooooooooooooooooo baybeh |
What is humus formed by? | decomposition of plant remains, animal waste and dead animals |
What helps to retain moisture ? | Humus |
removal of topsoil by different agents of weathering? | Soil erosion |
What is the prime factor of soil erosion? | Running water |
Does soil erosion help in soil formation? | yes |
How does soil erosion help in soil formation? | As the soil removed is deposited elsewhere |
What does soil erosion do? | Disturb the agricultural pattern |
Erosion where the soil is pulverised by heavy drops and hailstones | Splash erosion |
In case of which rainfall does splash erosion occur? | Convectional rainfall |
Due to heavy rains, a surface film of water carries away even surface layer of the topsoil as it moves? | Sheet erosion |
Another name for Rill erosion? | Gully erosion |
In which kind of erosion does cut steep sided valleys as it runs off? | Gully/Rill erosion |
What cuts up agricultural land into bad land where no cultivation is possible? | Gully erosion? |
Chambal ravines is an example of what? | Gully erosion |
Soil erosion by wind occurs on which kind of lands? | extensive flat lands |
How does the upper soil become loose and susceptible to wind erosion? | By lack of moisture |
How does soil erosion by overgrazing occur? | When wind erosion occurs as soil devoid of vegetation is directly exposed to wind |
Where is shifting agriculture common? | North east India |
Is lack of crop rotation a faulty measure of agriculture? | Yes |
Wrong ploughing is not a method of faulty agriculture. True or False | False |
An effort made by man to prevent soil erosion to retain the fertility of soil | Soil conservation |
How can constructing dams and barrages help in soil conservation? | Construction would check the speed of water and save soil from erosion |
Give an effective measure of ploughing | Contour method of ploughing |
Give an effective measure against Rill erosion? | Terrace farming |
How does terrace farming keep a check on soil erosion? | controls the direct flow of water down the slope |
How would planting cover crops check soil erosion? | Plant roots hold the soil together |
How can the velocity of wind to prevent wind erosion can be checked? | BY planting belts of trees, shrubs etc |
How have soils of peninsular India been formed? | Disintegration of rocks in situ |
What does "disintegration of rocks in situ" mean? | formed directly from the underlying parent rock |
Other name for the soils of peninsular India? | Sedentary soils |
What are northern plains also known as? | extra peninsular India |
What part of India's soil is formed by transported or residual alluvium? | Northern plains (ex situ soils) |
What are alluvial soils? | Transported/ex situ soils |
In which section are the alluvial soils coarsest? | Upper section |
In which section are alluvial soils finest in? | Delta region |
Which soil supports the maximum share of agricultural products and the bulk of Indian products? | Alluvial Soils |
What percentage of India's land do alluvial soils occupy? | 45.6% |
Another name for alluvial soils? | Riverine soils |
Which type of soil is made up of newer alluvium? | Young khadar soil |
Which type of soil is made up of older alluvium? | Old bhangar soil |
What kind of soil contains fine sand and silt? | Young khadar soil |
Which kind of soil contains kankars and pebbles? | Old bhangar soil |
What colour is young khadar soil? | Pale brown |
What colour is old bhangar soil? | vary from light grey to ash grey |
Where are young khadar soils found? | lower levels near the rivers |
Where are old bhangar soils found? | 30m above flood levels of rivers |
Which type of soil is more fertile...young khadar or old bhangar? | Young khadar soil |
What crops are alluvial soils suitable for? | Wheat,sugarcane,rice,cotton and oilseeds |
In delta region, alluvial soils is suitable for which crop? | Jute |
What colour are alluvial soils of north India? | Pale brown |
What colour are alluvial soils of South India? | Darker in colour |
Why are alluvial soils of south india darker in colour? | as rivers of deccan plateau flowing through black soil region carry the same to the delta |
Are alluvial soils of northern India porous and sandy? | Yes |
Are alluvial soils of Southern India porous? | Yes |
Ae alluvial soils of Southern India sandy? | No , they are clayey. |
What kind of crops are alluvial soils of north India suitable for? | Wheat crop |
What kind of crops are alluvial soils of southern India suitable for? | Rice crop |
Another name for alluvial soils of southern India? | Deltaic alluvium |
Another name for black soils? | Regur/ Black cotton soils |
Why is black soil also called black cotton soil? | as cotton is the most grown crop in these soils |
Are black soils in situ or ex situ? | In situ (residual soils) |
How have black soils been formed? | by weathering of basic lava of the deccan trap |
Do black soil retain moisture? | yes and they also become sticky (ew) |
Which soil is self ploughing? | Black soil |
How can the black colour be observed? | from black crystalline schists and basic gneisses |
How much percentage of clay does black soil have? | 60% |
What are black soils deficient in? | phosphates, nitrogen and humus/organic matter |
State true or false: Black soils of uplands are very fertile | False |
Are black soils sedentary soils? | yes |
Black soil is vastly confined to which area? | Deccan plateau |
Are red soils in situ or ex situ? | In situ |
How are red soils formed? | by weathering of ancient crystalline and metamorphic rocks |
What are the parent rocks of red soil? | acid granites and gneiss |
How much percentage of Indian land do red soil occupy? | 10.6% |
where does the red soil get it's colour from? | iron oxide content |
What is the nature of red soils? | porous and friable |
What do red soils lack in? | Lime , magnesia, phosphate , nitrogen and humus |
What are red soil rich in? | potash |
What does laterite mean? | "brick" |
How are laterite soils formed? | by heavy rainfall and high temperature with alternate wet and dry periods |
When does the formation of laterite soil take place? | during monsoon |
The process by which soluble minerals like lime dissolve in rainwater and percolate to they bottom leaving the topsoil infertile? | Leaching |
Which type of soils harden like iron when exposed to air? | Laterite soils |
How are laterite soils red in colour? | Due to presence of Iron oxide |
What texture do laterite soils have? | coarse |
What nature do laterite soils have? | friable and porous |
What minerals are laterite soils rich in? | iron oxide |
Why do laterite soils lack fertility? | intensive leaching |
Do laterite soils respond to manuring and irrigation? | Yes |
Laterite soils are suitable for which kind of crops? | Plantation crops |