Soil

Question 1

Short note on soil

Answer 1

soil is the most important natural resource. it’s the medium of plant growth and it supprts many other life forms. soil is a living system. it takes millions of years to form soil just upto a few cm in depth

Question 2

Factors which contribute to the formation of soil

Answer 2

-parent rock/ bedrock
-time
-vegetation and other life forms
-relief
-climate

• various forces of nature, like temp., actions of running water, wind, glaciers, etc. contribute to the formation of soil.
• chemical and organic chamges which take place in the soil are equally important.
  -soil contains organic(humus) and inorganic materials

Question 3

Alluvial soil

Answer 3

-most widely spread and most important soil
-northern plains
-3 main river systems
- rajasthan and gujarat - narrow corridor
- eastern coastal plains: mahanadi, godavari, krishna and kaveri
-sand, silt and clay
-bigger in size- inland towards river valleys
- upper regions of river valleys - coarse-> piedmont plains : chos , duars, terai
-bangar and khadar
- fertile
- potash, phosphoric acid and lime
-sugarcane, paddy, wheat and other cereals and pulse crops
- intensely cultivated, densely populated
-drier areas- more alkaline - proper and irrigation

Question 4

black soil

Answer 4

• black
  -regur
  -black cotton soil
  -parent rock, climate
  -deccan trap region(basalt region)
  -northwest region of deccaan plateau
  -lava flows
  -plateaus of maharashtra, saurashtra, malwa, madhya pradesh, chattisgarh
  -south direction along godavari and krishna valleys
  -fine, clayey
  -hold moisture
  -calcium carbonate, magnesium, potash and lim. deficient in phosphoric content
  -hot weather- dry up: cracks -> areation
  -tilled- first shower/ pre-monsoon period

Question 5

Red and yellow soil

Answer 5

• red soil develops on ccrystalliine igneous rocks in areas of low rainfall in southern and eastern parts of dedccan plateau
  -odisha, chattisgarh, southern parts of middle ganga plain along piedmont zones of western ghats
• red colour- diffusion of iron into metamorphic and igneous rocks
• yellow- hydrated form

Question 5

laterite soil

Answer 5

-later: brick
-tropical and sub-tropical conditions with alternating wet and dry season
-deep- very deep, acidic
- intense leaching
deficient in plant nutrients
-southern states, western ghats of maharashtra, odisha, parts of west bengal and north- east regions
-humus rich -deciduous and evergreen forests
-humus poor- sparse vegetation and semi- airid environment
- erosion and land degradation prone: position on landscape
- soil conservarion techniques- hilly areas of karnataka, kerala and TN - tea and coffee
-red laterite- AP , kerala, TN - cashew nut

Question 6

Arid soil

Answer 6

• red- brown
  -sandy, saline
  -salt content high - common salt : evaporating water
  -dry climate, hight temp- > evap is faster -> humus low and moisture is low
  -lower horizons- kankar: increasing calcium content downwards
  -restricts infiltration of water
  -proper irrigation- suitable for cultivation

Question 7

Forest soils

Answer 7

• hilly and mountaineous regionss- rainforests
  -texture- mountain environment
  -loamy and silty- valley sides
• coarse grained- upper slopes
  -snow covered areas- denudation, acidic, low humus content
• lower parts of valley- on river terraces and alluvial fans: fertile