Soil resources Flashcards
topmost layer of Earth’s land surface
Soil
from what are soils derived and by what process?
- from parent rock material
2. process of wear and tear
Decomposed vegetal and animal remains
Humus
Constituents of soil
humus, Silica.clay and sand
strength of soil to support plant life
Soil fertility
____ improves soil structure and fertility
Organic matter
Residual/sedimentary soil is also known as __________
In situ soil
what is in situ soil and example….
- formed in original position by breakup of parent rocks
2. Red soil,desert soil,black soil
transported soil is also called
ex situ soil
What is ex situ soil and example…
- soil transported by various agents
- no well defined profile
- alluvial soil
How are alluvial soils formed?
by the sediments brought down by rivers
what do the rivers deposit in the plains during their journey
alluvium
alluvial soil is also known as _________.
it is known so because…..
Riverine soil as it is mainly found in river basins
alluvial soils occupy ___ of the land area
40%
entire Northern plains consist of ____ soil
Alluvial
Three river systems which deposit alluvial soil ______
indus, ganga, brahmaputra
two types of alluvial soil
bhangar and khadar
_____ is older alluvium and composed of ______ called _______
Bhangar ,lime nodules, kankar
bhangar has a ______ composition
clayey
_______ is newer alluvium
Khadar
why is alluvial soil the most important in India
It contributes the largest share to agricultural wealth of India
Coastal alluvium is of _____ origin
Tidal
In the upper reaches of river valley…. soil is __________ and the particles are ____
coarse,large , non uniform
in the lower parts of the river valley…. soil is ____ and ____
small and uniform
How is alluvial soil …
light and porous
easily tillable
alluvial soil is rich in what minerals
potash, lime
alluvial soil is deficient in _______
nitrogen and humus
what crops can be grown in alluvial soil ( RSTW and 2 other )
Rice
Sugarcane
Tobacco
Wheat
Gram and oil seeds
What are some names for black soil?
Regur soil
Black cotton soil
Lava soil
How is black soil formed
denudation of volcanic rocks