Example of igneous rock
Diorite
Gabbro
Peridotite
All of these
Sedimentary rocks are …
Limestone
Andesite
Basalt
None
Which is incorrect regarding formation
Slate from sandstone
Gneiss from granite
Quaetz from quartz
None
Potash dominate minerals
Micas
Feldspare
Quartz
Olivine
Boro – alumino silicate
Olivine
Tourmaline
Quartz
All of these
Source of Mg
Brucite
Carbamate
Muscovite
None
Most resistance mineral to weathering
Augite
Muscovite
Biotite
All of these
Acids rocks are
65 – 70 % silica
40 -55 % silica
55 – 65 % silica
None
Chemical weathering involve
Disappearance of certain mineral
Formation of secondary mineral
Both
None
Kankar found in
Red soils
Black cotton soils
Both
None
1
Iron pyrite formation through
Oxidation
Reduction
Hydration
Hydrolysis
Highest element in earth crust
Al
Fe
Si
Oxygen
Active factors are
Climate
Parent material
Topography
Time
Washing out is
Horizonation
Illuviation
Eluviation
Humification
Removal of sesquioxides called
Podozolization
Laterization
Pedoturbation
Salination
Zonal soil forming process is
Pedoturbation
Salination
Podozolization
None
Soil includes
A horizon
A +B horizon
A , B, C horizon
All of these
The soil horizon where maximum biological activity occurs are
O 1
O 2
A
B
Father of soil science
V .VDokuchaev
Kellogg
Baldwin
Marbutt
Pedology is derived from …..
Greek word
Latin word
French word
None
Loose earth material above solid rock is
Soil
Solum
Regolith
Regosol
Organic soil must contain about
20 % OM
>20 % OM
<20 % OM
NONE
Portion of mineral soil volume basis
45 %
5 %
25 %
20 – 30 %
Which is not components of soil…
Air
Water
Organic matter
Light
Law of Minimum is given by
Von liebig
Bray
Stout
None
Relative proportion of sand and silt and clay
Soil texture
Soil structre
Soil compaction
None
Size of clay particle
>0.002mm
0.02 -0.002 mm
0.02-0.2 mm
< 2mm
Clay soil called …
< 40 % clay
>40 %
40 %
None
Individual aggregates are
Peds
Clod
Both
None
The arrangement of primary particle are
Soil texture
Soil structure
Soil compaction
None
Peds are arranged in relatively thin horizontal layers ….
Platy like
Prism like
Block like
None
Prism like most commonly found in ……
A horizons
B horizons
Both
None
Shapes of soil structure good for agriculture …..
Platy like
Prism like
Blocky like
Spheroidal
How much classes of soil structure …
5
4
3
2
Soil grades refer to ….
Degree of aggregation
Arrangement of primary soi particle
Proportion of soil particle
None
Particle density of mineral soil …
2. 60 g/cm3
1.3g/cm 3
1.1 g /cm3
None
Soil volume is …
Vs +Vp
Ws+Wp
Both
None
% Pore space
100- (BD/PDX100)
100- (PD/BDX100)
BP/PD X100
NONE
Soil temperature for root development
10 -27 C
15-45 C
20 C
None
Silicate colloids particle carrying negative charge ….
Micelles
Micro pores
Macro pores
None
Water molecule are carried by adsorbed cation …
Holmontz layer
Stern layer
Gunny layer
Ionic layer
Cation dominate in humid region
Ca2+
Al 3+
H +
All of these
Order of strength of adsorption to focculate soil collids
Al 3+>H+>Ca2+>Mg2+ > K+>Na+
Al 3+>H+>Ca2+> Na+>Mg2+ > K+
Na+> Al 3+>H+>Ca2+>Mg2+ > K+
None
Range of molar ratio in laterite soil
3-4.3
>2.5
2 -2.5
<1.33
Formula of goethite
Fe2O3.H2O
FeOOH
Both
None
Allophane is
Amorphous
Developed from volcanic ash
Adsorb cation
All of these
Tetra hedral is
Silicate dominate sheet
Al – dominate sheet
Mg – dominate sheet
None
1:1 type clay mineral is
Kaolinite
Halloysite
Nacrite
All of these
Expanding minerals are
Vermiculite
Smectite
Saponite
All of these
CEC of montroillonite is
80 -150
3- 10
10 -40
100 – 150
Non expanding minerals are
Illite
Chlorite
Both
None
Ferro- magnesium silicates are
Chlorite
Illite
Vermiculite
Kaolinite
Total soil order
2
10
11
9
Embryonic soil with few diagnisticsfeature , found in humid region
Spodosol
Inceptisols
Entisols
Histosols
Soil order have shrinkage and swelling property
Vertisols
Aridisols
Ultisols
Mollisols
Cat clay contain …
Sulphur
Calcium
Silicate
Boron
Most abundate soil in india
Black soil
Alluvial soil
Red soil
Laterite soil
Newar alluvium soil called
Khadar
Bhangra
Both
None
Black soil are derived from
Granite
Quartz
Limestone
None
Clay group dominate in black soil …
Montmorillonite
Beidelitic
Both
None
Red colour of soil due to
Postash
Humus
P2O5
Fe
Weight of 1 furrow slice
2x10^6 kg/ha
3x10^6 kg /ha
4x10^6kg/ha
None
Nitrogen content in humus
50%
35 %
5%
3 %
Medium molecular weight and alkali soluble but acid insoluble
Fulvic acid
Humin
Humic acid
None
Which is most susceptible to microbal attack
Fulvic acid
Humin
Humic acid
All of these
C:N ratio of humus
9:1
10:1
15:1
None
Humus have
Low plasticity and cohesion
Negative charge
High pH
All of these
Value of Bemlen factor
1.724
1.64
1.54
1.44
Muck soils are
Low decomposed
Highly decomposed
Both
None
C: N ratio >20 takes place
Immobilization
Both immobilization and mineralization
Mineralization
None
Range for high nitrogen
250 kg /ha
250 -500 kg /ha
>500 kg/ ha
None
Mineralization process occur through
Aminization
Ammonification
Nitrification
None
Voltalization is losses of
NH3
NO3
NO2
Nitrification occurs through
Nitrosomonas
Nitrobacter
Both
None