[Mission 2023] INSIGHTS STATIC QUIZ, 08 August 2022 – Geography

Solution: c)

Laterite soils are formed from chemical decomposition of rocks. These soils mainly contain iron oxide which gives them characteristic pink or red colour.

These soils are found in Central, Eastern and South India. These are residual soils formed from basalt and have high specific gravity.

Solution: b)

The black soils are generally clayey, deep and impermeable. They swell and become sticky when wet and shrink when dried. So, during the dry season, these soil develop wide cracks. Thus, there occurs a kind of self ploughing’.

Black soil is important for growing of crops like cotton and sugarcane. Laterite soil is more suited to grow plantation crop. 

Saline soils are also known as Usara soils. Saline soils contain a larger proportion of sodium, potassium and magnesium, and thus, they are infertile, and do not support any vegetative growth. They have more salts, largely because of dry climate and poor drainage. They occur in arid and semi-arid regions, and in waterlogged and swampy areas.

Solution: d)

The laterite soils develop in areas with high temperature and high rainfall. These are the result of intense leaching due to tropical rains. With rain, lime and silica are leached away, and soils rich in iron oxide and aluminum compound are left behind.

Red soil develops on crystalline igneous rocks in areas of low rainfall in the eastern and southern part of the Deccan Plateau. Along the piedmont zone of the Western Ghats, long stretch of area is occupied by red loamy soil. Yellow and red soils are also found in parts of Odisha and Chattisgarh and in the southern parts of the middle Ganga plain. The soil develops a reddish colour due to a wide diffusion of iron in crystalline and metamorphic rocks. It looks yellow when it occurs in a hydrated form.

The black soils are generally clayey, deep and impermeable. They swell and become sticky when wet and shrink when dried. So, during the dry season, these soil develop wide cracks. Thus, there occurs a kind of ‘self ploughing’. Because of this character of slow absorption and loss of moisture, the black soil retains the moisture for a very long time, which helps the crops, especially, the rain fed ones, to sustain even during the dry season.

Solution: d)

The Andaman and Nicobar Islands have a tropical rainforest canopy, made of a mixed flora with elements from Indian, Myanmar, Malaysian and endemic floral strains.

The South Andaman forests have a profuse growth of epiphytic vegetation, mostly ferns, and orchids. The Middle Andamans harbours mostly moist deciduous forests. North Andamans is characterized by the wet evergreen type, with plenty of woody climbers. The North Nicobar Islands are marked by the complete absence of evergreen forests, while such forests form the dominant vegetation in the central and southern islands of the Nicobar group. Grasslands occur only in the Nicobars, and while deciduous forests are common in the Andamans, they are almost absent in the Nicobars.

This atypical forest coverage is made up of different types, namely:

• Evergreen forest
• Tropical evergreen forest
• Semi-evergreen forest
• Moist deciduous forest
• Littoral forest
• Mangrove forest
• Brackish water mixed forest
• Submontane forest

Solution: a)

Earthquake waves get recorded in seismographs located at far off locations. However, there exist some specific areas where the waves are not reported. Such a zone is called the ‘shadow zone’.

An important fact about S-waves is that they can travel only through solid materials. This characteristic of the S-waves is quite important as it has helped scientists to understand the structure of the interior of the earth.