SOILS Flashcards
1
Q
a hexagonal column of soil measuring from 1 to 10
m2 in top surface area
A
Pedon
2
Q
an essential soil individual, comprising an
identifiable series of soils in an area
A
an essential soil individual, comprising an
identifiable series of soils in an area
3
Q
the study of soils
with principal interest on characterization and
differentiation of their properties and with only
minor emphasis on their practical use
A
Pedological approach
4
Q
the study of soils
with emphasis on their practical use, particularly
the relationship of soil properties to plant growth
A
Edaphological approach
5
Q
characteristics, processes, or reactions of
a soil caused by physical forces
A
Soil Physics.
6
Q
interactions of solid, liquid, and gaseous…,·
phases or components of soil
A
Soil Chemistry
7
Q
protection of
soil against physical loss by erosion or cher:n1ca
deterioration
A
Soil Conservation and Management.
8
Q
deals witfi tche
structural characteristics, mode of origin, and systematic
arrangement of soils
A
Soil Survey and Classification
9
Q
structural chemistry of the solid
components of soil
A
Soil mineralogy
10
Q
deals with the allocation of lands for general
or broad purposes such as agriculture, forestry,
settlement and military reservations
A
Land use:
11
Q
Mineral matter, 45%
A
12
Q
Organic matter, 5%
A
13
Q
most soils contain less than 20%
organic matter, thus classified as mineral soils
A
14
Q
Soil pores N O2 and C02
A
78, 20 , 0.5
15
Q
a solvent that can release
nutrients from minerals.
A
carbonic acid
16
Q
aggregates of minerals
A
Rocks
17
Q
study of rocks
A
Petrology
18
Q
The most common soil-forming igneous rocks are
A
granite, diorite, gabbro, ryolite, andesite, basalt,
and obsidian
19
Q
Granite and diorite are lighter in color due to the
high proportion of light-colored minerals such as
A
feldspar and muscovite.
20
Q
Gabbro is dark in color due to the predominance of
dark-colored minerals such as
A
biotite, hornblende,
and augite.
21
Q
Granite is acidic while basalt is basic.
A
22
Q
are among the dominant soilforming
rocks in the Philippines
A
Basalt and andesite
23
Q
The most important soil-forming sedimentary
rocks are
A
limestone, dolomite, sandstone, and
shale.
24
Q
process of sedimentation
A
fragmentation, transport, and recementation
25
Limestone is made up chiefly of the
mineral, calcite or CaC03.
26
also a carbonated material composed
of calcium magnesium carbonate CaMg(C03h.
Dolomite
27
is made up of fine particles of clay which
become consolidated after deposi't'on · bedie of
water.
Shale
28
Soils derived from limestone are soil series-.,, of
Faraon, Bolinao, Binangonan, and Alimodian which
are the soils in Cebu and Bohol
29
Soils derived from shale/ sandston are soil series
of
Alaminos, Bantay, Bauang, Lugo and Ubay.
30
The most typical soil-forming metamorphic rocks
are
gneiss, schist, quartzite, slate, and marble
31
metamorphic form of limestone.
marble
32
happens when the magma is ejected out of the
earth's crust through volcanic eruption and
solidifies on the surface
There is abrupt cooling
Extrosive {volcanic} formation
33
happens when magma solidifies within the earth's
crust
Introsive {plutonic} formation
34
Oxygen
46.6
35
Silicon
27.7
36
Aluminum
8.13
37
Iron
5
38
magnesium
2.09
39
calcium
3.63
40
sodium
2.83
41
potassium
8.13
42
a naturally occurring inorganic substance with
more or less definite chemical composition and
specific physical properties
Mineral
43
study of minerals and their properties
Mineraloqv
44
persist in the soil in their original state due to high
resistance to decomposition
Primary minerals
45
contributes K
upon weathering
Orthoclase, (anorthite)
46
contributes Na upon weathering
Sodium-plagioclase, (albite)
47
cotributes calcium upon weathering
calcium palgioclase
48
white mica
muscovite
49
black mica
biotite
50
quartz
microline
51
most important primary minerals
Quartz
Orthoclase
Sodium-plagioclase
Calcium-plagioclase
Muscovite
Biotite
Hornblende
Augite
Apatite
52
arise from the chemical breakdown of the least
resistant primary minerals
Secondary minerals
53
The more commonly occurring secondary minerals
are:
Calcite
dolomite
gypsum
limonite
hematite
gibbsite
kaolinite
montmorillonite
illite
54
refers to the
imperceptible movement of rock formation
towards the earth's surface resulting in cracking or
rocks.
unloading
55
the reaction of water with the
mineral resulting in the destruction of the
original chemical structure and the formation
of an acid and base
hydrolysis
56
nvolves the reaction of water
with the mineral but not leading to the
destruction of the chemical structure; The
result is a rigid attachment or association with
a water molecule.
hydration
57
reaction of carbonic acid with a mineral to produce a
soluble product
carbonation
58
the dissolution of minals thrgh
the solvent action of H2C03 o H ions which
results into the separation or dissociation of
component cations
solution
59
affects the amount of leaching that takes
place in the soil and the speed with which soil horizons
develop
Climate
60
factors of soil fomation
climate
living organism
relief or topography
parent material
time
61
For every 10 °C rise in temperature, the rate of
biochemical reactions doubles.
62
the mixing of the soil by o ganisms
bioturbation
63
Soils of forested areas
dipterocarps
64
the partly weathered mineral or organic debris
from which true soil (solum) is formed
Parent material
65
those that develop in
place and formed from the rock below where it
is found
sedentary or residual.
66
those which are transported by
various agents and deposited in other sites
where they form the soil. The different types
based on the agent and manner of transport
are the following:
transported.
67
accumulated from running
water
Alluvium
68
materials that are
accumulated in former lakewaters
Lacustrine
69
materials that are
accumulated in former oceans
Marine
70
those that are
carried and deposited by moving
glaciers
galcial till or moraine
71
those that are carried and
deposited by the wind
aeolian
72
a stratified rock
hardened (lithified) from deposited
fine dust or ash emitted on a volcanic
eruption
volcanic tuff
73
transported and deposited by gravity
collovium
74
is generally a young soil because ot
the constant deposition which re\ev s the parent
material.
Alluvial soil
75
Old soils have thick solum but are generally acidic
and low in fertility
76
a vertical cross section of the soil exposing
all of its horizons
Soil profile
77
a layer of soil or soil material
approximately parallel to the land surface and differing
from adjacent horizons in physical, chemical and biological
properties
Soil horizon
78
process wherein each horizon
acquires distinctly different properties from the others due
to various mechanisms of addition, losses, translocation
and transformation
Horizon differentiation
79
mechanism of addition and transformation
enrichment
melanization
comulization
80
mechanism of translocation
illuviation
calcification
decalcification
salinization
akalinization
podzolization
laterization
leucinization
lessivage
81
general term for the addition of any
material to the soil body
Enrichment
82
admixing of organic matter to the
mineral matter which darkens the soil
Melanization
83
addition of mineral matter trough wind
and water to the soil body
€umulization:
84
general term for the movement of soil
material from one part of the soil to another resulting in
the formation of argillic (clayey) layers
illuviation
85
the transfer and accumulation of calcium
carbonate in particular soil horizon
Calcification
86
removal of calcium carbonate from the
soil horizon
decalcification
87
accumulation of soluble salts of sulfates
and chlorides of calcium, magnesium, sodium and
potassium in certain horizons
salinization
88
accumulation of sodium
ions
Alkalinization (solonization)
89
the translocation of
aluminium and iron and/or organic matter thus,
concentrating the silica in the leached layer
Podzolization (Silication)
90
the transfer of silica from
the solum, thus concentrating the aluminium and iron
oxides and sesquioxides in the leached layer
Laterization (Desilication
91
paling or loss of dark colorof the soil
due to the removal of organic matter from the solum
Leucinization
92
movement fo the fine mineral particles from the top soil resulting in the enrichment of clay of lower horizons
lessivage
93
A and B, zone of pedogenic activity; considered
as the true soil because these are the layers reacheqand
used by the roots as source of water and nutrient
Solum
94
all loose materials above the bedrock (A,B,
and C horizons)
Regolith
95
Horizon dominated by organic matter
o
96
Organic-rich, mineral horizon at or adjacent to the
surface
A
97
Mineral horizon of maximum eluviation
E
98
Mineral horizon of maximum illuviation and formed
beneath an O,A, or E
B
99
Weathered parent material
C
100
underlying consolidated bedrock
R
101
Mainly influenced by the addition of
organic matter
Surface Horizons:
102
developed due to the translocation,
transformation and losses
Subsurface horizons
103
the relative proportion of the various size
fractions: sand, silt and clay in the soil
Soil Texture
104
No amount of organic matter added can alter soil
texture
105
provide for the
framework for the soil
sand and silt fractions
106
usda
United States Department of Agriculture
107
issa
International Soil Science Society
108
Sand
2 - .05 (USDA)
2 -.02
109
silt
.05 - .002
.02 - .002
110
clay
<.002
111
shows the percentage of sand, silt
and clay at various textural classes.
Textural Triangle:
112
The moist sample is kneaded into a od an
texture is approximated by the abilit to form
or of the rods to remain intact bent i
loop
Roll method
113
states that the settling
velocity of soil particles in an aqueous medium is
directly proportional to the square of their
diameter multiplied by a constant
Stoke's Law of
sedimentation
114
-Destroying the organic matter to remove the
cementing material of the soil separates
-Dispersing the soil vigorously with sodium
hexametaphosphate
Hydrometer method
115
refers to the clustering of the soil particles into
characteristic aggregates of various sizes, shapes
and stability
Soil structure
116
The major cementing agents in soil structure
formation are
colloidal clay, oxides of iron and
aluminium (sesquioxides) and organic matt r
117
Calcium-rich ( calcareous) soils are generally
well granulated while sodium -rich (sodic) soils
are highly dispersed
118
The best soil structure for good plant growth is the
granular specifically, crumb structure because it
has good distribution of large and small pores.
119
The best soil structure for good plant growth is the
Granular / crumb structure
120
pillar-like with level tops
Prismatic structure
121
pillar-like with rounded tops; like
prismatic structure, commonly occur in subsoils and in
soils of arid and semi-arid regions
Columnar structure
122
cube-like and has more or less sharp
edges and the rectangular faces are distinct
Blocky structure
123
has edges which are
more or less rounded; like the blocky structure, typical in
clayey subsoils particularly in humid regions
Sub-angular blocky structure
124
has disc-like aggregates; commonly
found in virgin soils and subsoils
Platy structure
125
rounded aggregates which are
more porous; characteristic of surface soils especially
those high in organic matter content
Spheroidal structure
126
fraction of the soil volume occupied by air and
water
Soil pore spaces
127
are formed in
between aggregates; they drain excess water
macropores
128
are formed
within the aggregate; they store water.
micropores
129
-the mass (dry weight) per unit volume of soil
-a measure of degree of compaction of the soil
and an indicator of porosity
Bulk density
130
The range of bulk density values for sand and
sandy loam soils is
1.2 - 1.8
131
The range of bulk density values for clay, clay
loam and silt loam is
1 - 1.6
132
normal bulk density
1 - 1.3
133
- mass (dry weight) per unit volume of soil
excluding the pore spaces within that soil volume
- may indicate the mineral ancestry of the soil
Particle density
134
may indicate soils have
high organic matter
PD of < 2.5
135
P. D. of organic matter is
1.2 - 1.5
136
As the bulk density approaches the value of the
particle density, the percentage porosity
approaches zero.
137
the volume of soil pore spaces left occupied by air after the other pore spaces are filled with moisture
aeration porosity
138
the force by which water is held in the soil
Soil moisture tension {SMT)
139
1 atm
1.01325 bar
140
1 bar
0.9869 atm
141
A graph showing the relationship between
moisture content and moisture tension of the soil,
and the characteristic of the soil itself
Soil moisture -release curve
142
MC by weight (MCw)
- the weight ( or mass) of water per unit weight of
soil in which it is contained
Gravimetric.
143
MC by volume (MCv)
- the volume of water per unit of bulk volume
including soil solids plus pore spaces of the soil
Volumetric.
144
All pore spaces are completely filled with water
(maximum water holding capacity)
Water at saturation; SMT = 0
145
An estimate of the upper limit of the available
moisture range
Field Capacity {FC}; SMT = 1/3 bar;
146
an estimate of the lower limit of the available
moisture range
Permanent Wilting Point {PWP}; SMT = 15
147
the water film at the immediate surface of the soil
particle
Hygroscopic {water} coefficient; SMT 31
148
Computed by getting the difference between FC
and PWP
Available Water{AW}
149
- also called drainage water; the water which soon
drains out of the macropores
- the difference between the water at saturation and
the water at field capacity
Gravitational water
150
small cubes of gypsum connected to wires and
buried at specified depths of the soil where water
status is to be monitored
Gypsum blocks
151
consists of a long tube filled with water and with a
porous cup buried in the soil and a mercury gauge
above the ground
Tensiometer
152
Upward movement of water
capillary movement
153
Downward movement of water
Infiltration and percolation
154
the downward entry of water via the
soil surface
Infiltration
155
the downward movement of water
through the soil; the water moves at a greater
depth in the soil profile
Percolation
156
the physical condition of the soil manifesting
cohesion and adhesion forces acting within the soil
at various moisture contents
Soil Consistency
157
soil is easily puddled
which is attained at paddy rice culture.
Liquid consistency
158
the soil is plastic and
sticky
Plastic consistency
159
Soil best for cultivation
since it is soft, friable, mellow and soil
structure is rejuvenated.
Friable consistency.
160
the soil is hard and
requires high energy to pull the plow, resulting
to cloddy seed bed.
Harsh/ hard consistency
161
are very old soils which
are acidic and low in basic cations.
reddish soils
162
in subsoils indicates good
drainage.
Red yellowish color
163
indicates poor drainage.
Dark bluish or grayish color
164
are generally more fertile
dark colored soils
165
the standard color comparison chart
munsell color chart
166
the dominant spectral color
hue
167
darkness or lightness of color
value
168
gradation of purity of color
intensity or brightness of a color
chroma
169
very small particles of matter (0.2 micron to 1
micron)
Soil colloids
170
-constituted by organic complexes occurring in
colloidal form
- represented by humus
constituted by organic complexes occurring in
colloidal form
171
The main source of negative charges in humus
dissociation of H+ from carboxylic and phenolic
functional groups at high pH.
172
types of inorganic colloids
Crystalline Silicate clays
Amorphous {non-crystalline} silicate clays
Amorphous Non-silicate clays
173
composed of sheet-structured alluminosilicates of
various types
Crystalline Silicate clays
174
types of crystallines sylicate clays
1: 1 non expanding type
2: 1 expanding type
2: 1 limited expansion type
2:1 non expanding type
2:2 type
175
1: 1 non expanding type
kaolinite and
halloysite
176
2: 1 expanding type
smectites
(montmorillonite)
177
2: 1 limited expansion type
(vermiculite)
178
2:1 non expanding type
(Illite)
179
2:2 type
( chlorite)
180
most chemically reactive type of crystalline sylicate clays
montmorillonite
181
represented by allophone and imogolite
Amorphous {non-crystalline} silicate clays
182
occur as amorphous hydrous oxides of Iron and
Aluminum
Amorphous Non-silicate clays
183
examples of amorphous non silicate clays
hematite
geothite
limonite
boehmite
gibbsite
184
arise mainly from exposed hydroxyl groups at the broke nedges of crystals
negative charges
185
Agriculture important soils are net-negatively
charged.
186
arise from the protonation or addition of H+ to OHgroups
on the edge of minerals such as
sesquioxides, allophone and kaolinite
positive charges
187
does not lsoe its color when it reacts to positve ly charged soil
eosin red
188
loses its color when it reacts to negatively charged soil
gentian violet
189
a reversible process by which ions are exchanged
between solid and liquid phases and between solid
phases if in close contact with each other
ion exchange
190
list of important cations
(NH4+, Ca2+,Mg2+, Na+, H+, K+)
191
list of important anions
(NO3-, PO4-, SO4- )
192
the ability of the soil to adsorb and exchange
cations with those in the surrounding
soil solution
as well as with the plant roots
Cation Exchange Capacity (CEC}
193
adsorption stregth order of cations
(Al3+ , H+)> Ca2+ > Mg2+ > K+ > Na+
194
the degree by which the exchange sites in the
colloids are occupied by basic cations
Percent Base Saturation (0/o BS}
195
list of basic cations
Ca2+, Mg2+, K+, Na+, NH4+,
196
the degree by which the exchange sites of colloids
are occupied by sodium ions
Exchangeable Sodium Percentage (ESP}
197
also referred to as soil reaction
soil pH
198
The lower the pH value, the higher is the W
concentration and the lower is the OHconcentration.
199
The most favourable pH for growing most
agricultural plants is between
6-7
200
The range of pH in the Philippines is
5.5 -6.5
201
When the pH is too low ( < 5.0, strongly acidic) these nutrients become less available
Ca, Mg, K, P, Mo, N
202
When the pH is too low ( < 5.0, strongly acidic) these nutrients become more soluble and toxic
Fe, Al, and Mn
203
When pH is too high (>8.0, strongly alkaline) most micronutrients becoem unavailable except
Mo
204
sources of acidity
H and Al3+ ions
Carbonic acid (H2CO3) dissociation
Organic Acids from OM decomposition
MIneral weathering
acid rain
heavy cropping
long term use of acidifying fertilizers
205
in high pH P becomes complexed with calcium
206
in high pH K also competes with the now abundant Ca for plant absorption
207
in high pH iron deficiency develops
208
in low pH P becomes complexed into insoluble forms with Fe and Al
208
in low pH P becomes complexed into insoluble forms with Fe and Al
209
In low pH P can also be precipitated as insoluble
manganese phosphate compounds
210
acidity due to W ions in soil solution
Active acidity
211
acidity due to H + and Al3+ ions adsorbed in
colloid surfaces
Reserve acidity
212
sources of alkalinity
Base forming cations
carbonates and bicarbonates
213
the strength of the lime in correcting soil
acidity with reference to calcium carbonate;
relative neutralizing value
214
RNV fo CaCO3
100%
215
RNV of Dolomite
109%
216
RNV of CaO
179%
217
RNv of Ca(OH)2
136%
218
list of liming materials
limestone
burned or quick lime
slaked lime
219
made up of CaCO3 and dolomite
limestone
220
made by
igniting calcium or magnesium carbonates;
quick lime
221
hydroxide of lime made by reacting
Cao or MgO with water
slaked lime
222
lowering the pH
acidification
223
facilitate the oxidation of sulfur compounds to sulfate
Thiobacillus
224
The acidity is due to the oxidation of sulfur
compounds in soils that are rich in sulfur
acid sulfate soils
225
- soils with toxic amount of soluble salt content
- with electrical conductivity (EC) greater than
4 mmhos/cm
saline soils
226
soils with excessive amount of soluble sodium (Na
content more than 15% of the CEC)
sodic soils
227
also referred to as dryland soils
upland soils
228
also referred to as paddy soils
lowland soils
229
in upland soil most nutrients exist in their oxidized state
230
in lowland soils most nutrients exist in their reduced state
231
probably the most significant microorganisms in
humid temperate region soils
7000 species worldwide
earthworm
232
most common species of earthworms
lumbricus terrestris and allolobophora calignosa
233
worms living the litter layer
epigeic (eisenia foetida)
234
worms living in the top 10-30 cm of soil
endogeic (allolobophora caliginosa)
235
worms living in the vertical burrow up to 1 meter
anecic (lumbricus terrestris)
236
Single-celled animals (20-50 microns in diameter)
-helps released the immobilized nutrients in the
bacteria
Protozoa
237
probably the most important in terms of their
effect on soil properties
bacteria
238
morphological grouping of bacteria
Cocci (speherical)
Rods (short, long, curved)
Spiral (vibrio)
239
- most adaptable and versatile soil organism
- able to decompose the resistant organic
compounds such as lignin, cellulose, and gums
- acid loving
fungi
240
an association between fungi and
plant roots which help plants in solubilization of P
and its absorption
Mycorrhizae
241
attack and simplify complex organic compounds
such as cellulose, chitin, and phospholipids
actinomycetes
242
actinomycetes antibiotic producers
Streptomycin,
Erythromycin
243
chlorophyll bearing organisms which thrive mostly
in soil surfaces
Algae
244
refers to the totality of all carbon-containing
compounds in the soil derived from either plants
or animals
Soii 'organic Matter {SOM}
245
Cellulose
(15 - 60%)
246
Hemicellulose
(10 - 30%)
247
Lignin
(5 - 30%)
248
Water-soluble fractions: amino sugars, amino
acids
(5 - 30%)
249
cultivated soil contain an average % of organic matter
2-3
250
is the enzymatic oxidation by soil
organisms under aerobic condition with CO2, heat
or energy and water as the major products.
Decomposition
251
Bacteria and Actinomycetes: inhibited at pH
5.5
252
is a
convenient tool for predicting the rate of
decomposition and regulating the quantity of
mineral nitrogen available to plant.
carbon nitrogen ratio
253
The higher the C/N ratio (usually 30), the slower is
the rate of organic matter decomposition because
the nitrogen is immobilized by microorganisms.
Soil microbes use whatever N is available
254
is the optimum C/N ratio of organic materials
for faster decomposition
20:1
255
conversion of organic N to inorganic N;
renders N available for plant use
Mineralization
256
conversion of inorganic N to organic N; renders N
unavailable for plant use
Immobilization
257
- the biological formation of NO3- or NO2 from
compounds containing reduced nitrogen
- The most common initial substrate is NH4- and the
final product is NO3-
Nitrification
258
chemoautotrophic, gramnegative,
non spore forming, ellipsoidal or
short rods, responsible for the oxidation of
NH4+ to NO2-
Nitrosomonas.
259
hemoautotrophic, gram-negative,
non- spore forming, short rods, further
oxidizes nitrite to nitrate.
Nitrobacter
260
the excess growth of plant and
algae,
eutrophication
261
health problem in infants and
animals led by excess nitrogen
methemog!obinemia
262
biochemical reduction of nitrate-N to gaseous N by
facultative anaerobic soil organisms
Denitrification
263
Denitrification is all aerobic but nitrate is used as
the electron acceptor in the absence of 02*
264
microorgansims involved in denitrification
Pseudomonas,
Achromobacter, Bacillus and Micrococcus
265
breakdown of organic matter such as dead anii:nals
and plants or waste materials like excrement
ammonification
266
enter and irritates the roothair causing
the formation of root nodules
rhizobia
267
microorganism involved in non symbiotic N fixation
Azotobacter
Beijinckia and CLostridium pasteurianum
268
common Blue Green algae in the PH
Anabaena
uariabilis, Gloetrichianatans, Nostoc commune,
Nostoccarneum, Hapalosophon sp., Anabaenopsis
spp. and Tolypothrix sp
269
Genera of bacteria capable of solubilizing Calcium
phosphates
o Pseudomonas
o Mycobacterium
o Bacillus
o Micrococcus
270
Genera of fungi capable of solubilizing Calcium
phosphates
o Penicillium
o Fusarium
o Aspergillus
271
fungus forms a mantle
around root exteriors hyphae enters into
spaces between plant cells
Edotrophic
272
fungus penetrates the
cells of the plants examples
Endomycorrhiza
273
The major sulfur in soil is in the organic fraction
274
In anaerobic conditions, sulfate availability may be
limited in the soil.
275
bacteria that reduces sulfate to sulfide
Desulfovibrio and Desulfotomaculum
276
bacterias capable of oxidizing sulfur to sulfate
Tiobacillus
277
bacteria that precipitates iron
iron bacteria
278
After composting, the C/N ratio of organic
materials is reduced to about
14-20:1
279
different stages of composting
mesophilic and thermophilic stage
280
one of the most abundant organic
matter in nature
Cellulose
281
genera of cellulose decomposting bacterias
bacillus,
Cellulomonas, Clostridium, Clorynebacterium,
Cytophaga, Polyangium, Sporioccytophaga and
Vibrio
282
genera of cellulose decomposting fungi
Aspergillus,
Chaetomium, Cuvularia, Fusarium,
Memnoniella, Phoma, Thielavia and
Trichoderma
283
aerobic, spore-f-orming, grampositive
rods
bacillus
284
short gram-negative rods
that produces yellow, water-insoluble
pigments
Cellulomonas
285
anaerobic, non-motile, gram
negative rod, which does not ferment
carbohydrates other than cellulose;
produces a yellow pigment
Clostridium
286
aerobic, long, flexuous rod
with pointed ends; abundant in soils
receiving straw or manure
Cytophaga
287
the capability of the soil to supply the nutrients in
the right amounts and proportions to meet the
nutrient requirement of the crop,
Soil fertility
288
the ability of the soil to support or produce a
desired quantity of plant yield
Soil productivity
289
A fertile soil is not necessarily a productive soil.
290
A productive soil is necessarily fertile.
291
the supply and absorption of chemical elements or
compounds required by the plant
Plant Nutrition
292
chemical elements or compounds required by
plants for normal growth
Nutrients
293
are mechanisms by which
elements are converted to cellular materials or as sources
of energy, or to drive reactions
Metabolic processes
294
major component of plant's organic compounds
CHO
295
-Energy storage and transfer through ATP - ADP
conversion
-Important in seed formation and development of
reproductive parts of plants
-Associated with increased root growth, early
maturity particularly grain development
P
296
-Enzyme activator
-Regulates osmotic pressure in roots
-Maintains turgor pressure of guard cells and
regulates opening of stomata, thus controlling
photosynthesis and transpiration.
-Needed in ATP synthesis
-Increases pest and disease resistance
K
297
-Enhances NOrN uptake and regulates cation
uptake
-Essential for cell elongation and division
Ca
298
-Constituent of chlorophyll molecule
-Structural component in ribosome
-Associated with energy transfer reactions from AP
in metabolic processes like photosynthesis,
glycolysis, TCA cycle, and respiration
Mg
299
Sulfur containing amino acids
cystine, cysteine and methionine
300
-Needed in synthesis of sulfur-containing amino
acids
-Needed in synthesis of coenzyme A, biotin, thiamin and gluta
-Enhances oil formation in flax and soybeans
-responsible for the
characteristic taste and smell of mustard and
onion.
S
301
Chlorophyll synthesis and in enzymes for electron
transfer
Fe
302
Catalyst for respiration, enzyme constituent
Cu
303
In enzyme systems that regulate various metabolic
activities
Zn
304
Controls several oxidation-reduction
formation of 02 in photosynthesis
Mn
305
believed to be important in sugar translocation and
carbohydrate metabolism
B
306
Needed for nitrogen fixation
Mo
307
Activates system for the production of O2 in photosynthesis
Cl
308
involved in the mobilization of nitrogenous
compounds
Ni
309
Essential for symbiotic nitrogen fixation
Co
310
Macronutrients
CHONPKCaMgS
311
Micronutrients
FeMnCuZnMoBClNiCo
312
the deficiency can be seen on older leaves
mobile nutrients
313
the deficiency can be seen on younger leaves
immobile nutrients
314
list of mobile nutrients
NPKMgZn
315
List of immobile nutrients
CuMnBoSCaFe
316
nutrients are carried by mass movement of water
as water is absorbed the roots
massflow
317
nutrients absorbed in massflow
Ca, Mg,
Zn, Cu, B, and Fe
318
the movement of ions from a zone of high
concentration to a zone of low concentration
Diffusion (ficks law)
319
nutrients supplied by diffusion
P and K
320
the direct exchange of ions between the toots and
soil colloids as roots come in contact with the
colloid
Contact exchange {interception)
321
proposes that ions enter an outer space in the
roots by diffusion
and a carrier energized by plant metabolism picks up
the ion and carries it to the inner space of the
roots
Carrier theory of nutrient uptake
322
occurs outside the casparian strip and
plasmalemma as a barrier to diffusion and ion
exchange
passive uptake
323
transport of ions into the inner cells requiring
energy due to the higher concentration of ions
beyond the plasmalemma and into the cytoplasm
which is against an electrochemical gradient (selective)
active uptake
324
nitrogen is taken up as
NO3 and NH4+
325
NH/ uptake is optimum at neutral pH and
decreases as pH decreases.
326
NO3- uptake increases with decreasing pH and
decreases with increasing pH
327
higher P
uptake at low pH (____) than at high pH (____).
4.0
8.7
328
is the only one essential nutrient cation which
can be transported against an electrochemical gradienst into plant cell
K
329
K uptake is high when plant is sufficiently supplied
with
N
330
K uptake and retention in plants are competitively
affected by
H+, ca++, Mg++ and Na+.
331
Plants with enough amount of K have lower
transpiration rate and require relatively lower
amounts of water
332
Ca content of legumes is higher in dicotyledons than in
monocotyledons and also higher in legumes than in other
species
333
Competitive relationship of Magnesium
NH4, K, Ca, Mn
334
upward translocation
acropetal
335
Plant growth is limited by that nutrient present
below the minimum requirement
Liebig's Law of Minimum
336
If plants were supplied with adequate amounts of
all nutrients except one, the growth is proportional
to the amount of this limiting element which was
added to the soil.
Mitscherlich's equation
337
temperature range for agricultural crops
15 - 45
338
soil physical properties
(texture, structure, bulk density;.,(10rosity,
water holding capacity, hydraulic conductivity)
339
soil chemical properties
(pH, CEC, base saturation, salinity, toxic
elements)
340
quantitative methods of soil fertility evaluation
soil analysis
plant tissue analysis
fertilizer field trials
pot experiments
341
qualitative method of soil fertility evaluation
nutrient deficiency symptoms
342
Principle: the amount of nutrient extracted by
chemical reagents at any one time is the amount
available throughout the growth period of the crop
Soil analysis
343
Main objective is to collect a small amount of soil
sample weighing
soil sampling
344
weight of soil collected in soil samplign
.5 kg
345
The nutrient content in the plant tissue is related
to the available nutrient supply of the soil.
Plant analysis
346
assesses the effect of fertilizer and their
interactions with all existing factors of in crop growth
and development in any given location
fertilizer field trials
347
comparison of several fertilizer treatments
including a control using small amount of soil in
pots to have a better control of environmental
factors
pot experiment
348
any substance that is applied to the soil or to the
plantin solid, liquid, or gaseous form to supply one
or more of the essential nutrient elements required
for the nutrition and growth of plants
fertilizer
349
no chemical has been
added to the finished product to increase
nutrient content.
pure organic fertilizer
350
has been enriched with
microbial inoculants, hormones or chemical
additives to increase nutrient content.
fortified or enriched organic fertilizer
351
kakawate N content
4% (glyricidia sepium)
352
single nutrient fertilizers are also called
straight fertilizer
353
multinutrient fertizers are also called
complex, compound or mixed fertilizers
354
contains the 3 primary
nutrients which are historically known to be
deficient in most soils
complete fertilizers
355
The nutrient content in fertilizers is written in
%N,
%P205 and %K20 in that order
356
highest N content among the solid
N-fertilizers (NH2)2CO; Hygroscopic and 100%
soluble
Urea
357
82% N has the highest
amount of N among all fertilizers; contained in
pressure tanks and is usually custom-applied by
injecting into the soil
Anhydrous ammonia
358
hygroscopic and
nearly 100% soluble; contains sulfur ( ~24%),
recommended for 5-deficient soils
Ammonium sulfate (20-0-0):
359
contains 20%
P2Os; Pelleted as grayish granules and has a faint
acid odor
Ordinary superphosphate {OSP}
360
monocalcium
phosphate monohydrate
triple superphosphate
361
common k fertilizer
muriate of potash or potassium chloride
362
weight percentage of the nutrients contained in a
fertilize
fertilizer grade
363
relative proportion of each of the primar nutrients
fertilizer ratio
364
when the fertilizer is spread evenly on
the soil surface; suitable for rice crop since they
are closely planted
broadcast
365
applied on the row
below the seed level or slightly on the side of the
seeds along the row; usually done for crops like
corn, sorghum, tobacco, and fruit trees
band placement
366
fertilizer is applied along the bottom
of furrow
In the row
367
fertilizer is applied around the base of the
plant or tree
ring
368
fertilizer is dropped in holes around the tree
hole
369
fertilizer is dropped in small amount on the
side of each hill or plant
spot
370
application sometime after plants have
emerged
topdress
371
In sandy soils, N is necessarily split as well as K
372
For heavy clays, all of N is sometimes placed at
planting
373
process by which raindrops
splash soil sediments from the soil surface into the runoff;
Detachment/dispersion
374
ransport of suspended soil particlesfrom
upslope to downhill direction whether in rills, between
rills and in sheet flow
Entraintment
375
process by which sediment settles out under
the action of gravity; a selective process depending on
particle size, being rapid for sand and slow for clay
Deposition
376
types of erosion
Geologic and accelerated
377
accelerated erosion rate
10mm/yr
378
soil particles are detached due to
the impact of raindrops and splashed at a Ion e
in the downslope than in the upslope direction
Raindrop erosion
379
-the uniform removal of thin layer or "sheet" of soil
from the land surface by rainfall and surface runoff
-the most widespread and probably the most
damaging form of soil erosion
sheet erosion
380
occurs where surface water has concentrated, so
that a large mass of water supplies the energy
both for detaching and transporting the soil
channel erosion
381
an erosion process in which
numerous small channels of only several
centimeters in depth are formed;
rill erosion
382
also known as advance rill
erosion due to the increasing size of rills
gully erosion
383
the carrying off of the soil
material on the sides and on the bed of a
permanent or intermittent stream
stream erosion
384
the potential ability of the rain
to cause erosion
Rainfall erosivity
385
the soil's vulnerability or
proneness to erosion which is influenced by
infiltration capacity and structural stability of the
soil
soil erodibility
386
Developed to estimate the rate of soil erosion
under various conditions
Universal soil loss equation
387
USLE-R
rainfall erosivity
388
USLE-K
erodibility
389
USLE-L
slopelength factor
390
USLE-S
slpe gradient
391
USLE-C
cropping system and management
392
USLE-P
erosion control practice
393
USLE-T
the maximum level of soil erosion that will
permit a high level of crop productivity to be
maintained economically and indefinitely
394
involves construction of broad channels
or benches across the slope to break the flow of
runoff water
terracing
395
refers to canals or channels
planted with grasses to provide outlets for disposal
of unavoidable runoff water
grassed waterways
396
a depression of considerable size located
below the check dam to collect runoff
pond
397
a structure above the pond which
retards run off velocity
check dam
398
the practice of covering the soil surface with
crop residues
mulching
399
involves planting of close-growing grasses and
legumes to cover and protect the surface of
the soil
cover cropping
400
recommended cover crops
tropical kudzu,
centrosema, calopogonium, guinea grass, para
grass, napier grass, Alabang
401
refers to the
growing of erosion-permitting crop and soilconserving
crop in alternate strips aligned on the
contour
Strip Cropping (Pilas-tanim)
402
the systematic planting of different crops in
succession on the same piece of land
Crop Rotation (Ikot-tanim)
403
involves the planting of two or more annual
crops with the second crop planted alter the
first crop has flowered or nearing its harvest
Relay Cropping (usod-tanim)
404
refers to a practice which increase crop
productivity while providing better protection
of the soil from erosion
Multiple Cropping
405
growing of two or
more crops a year in sequence
sequential cropping
406
growing
of two or more crops on the same piece of
land at the same time
inter or mixed cropping
407
system where arable crops are grown in the
alleys between rows of shrub/tree legumes
which are pruned periodically to prevent
shading and to provide green manure to the
companion crops
Alley Cropping (interhedgerow cropping)
408
commonly used contour hedges
ipil-ipil,
gliricidia, camachile
409
practice of increasing the
population of the crop per unit of land area with
due regard to the effect of crop competition
high density planting
410
refers to the system of land
management where woody perennials and
agricultural crops are raised at the same time or
sequentially
A groforestry
411
refers to a tillage system which leaves
30% residue cover after planting
Conservation tillage
412
plowing, harrowing and furrowing acros the
slope of the land
contour cultivation
413
preparation of the seedbed with minimal soil
disturbance
minimum tillage
414
tillage practice that leaves a large
percentage of residues
mulch tillage
415
preparation of seedbed by
conditioning the soil along narrow strips in and
adjacent to the seed rows
strip or zone tillage
416
practice of breaking up the hard pan
below the plow layer to increase infiltration and to
reduce runoff
subsoiling
417
the technique of connecting the ridges with
cross-ties to form depressions for storing
rainwater which is allowed to infiltrate later
ridge tying
418
an inventory of the soil resource describing the
characteristics of the soils in a given area
soil survey
419
refers to how many inches on the map
represents inches on the ground
map scale
420
- soil survey order
- very intensive ( detailed); experimental
plots, building sites; minimum size delineation is .< 1
hectare
first order
421
-SOIL SURVEY ORDER
intensive (detailed); general agriculture
urban planning; minimum size delineation is 0.6 to 4 has
SECOND ORDER
422
- SOIL SURVEY ORDER
extensive; rangeland, community area
planning; min. size delineation is 1.6 to 16 has
THIRD ORDER
423
- SOIL SURVEY ORDER
extensive (reconnaissaNce); ..for- br:Oad
land use potential and general land management; min.
size delineation is 16 to 252 has.
FOURTH ORDER
424
- SOIL SURVEY ORDER
exploratory; regional planning, nationa
planning; min. size delineation is 252 to 4000 has
FIFTH ORDER
425
refers to the system of ification
developed by the USDA Soil Survey
Soil taxonomy
426
Soil-forming processes as indicated by presence or
absence of major diagnostic horizons
order
427
subdivision of soil order based on moisture and
temperature regime
suborder
428
subdivision of suborder based on differences,
arrangement, and degree of expression between
soil horizons
great group
429
typic (central concept of the great group);
intergrades or transitional forms to other orders,
suborders, or great groups
subgroup
430
Properties important for plant root growth; broad
soil textural classes averaged over control section
or "solum"; mineralogical classes for dominant
mineralogy of solum; soil temperature classes
family
431
a class of soils and the basic units used to classify
soils
parent material; kind, number and arrangement of
horizons in the profile; kind and arrangement of
horizons; color, texture, structure, consistence and
reaction of horizons; chemical and mineralogical
properties of the horizons
series
432
distinct types of horizons that
reflect nature of soil formation
diagnostic horizons
433
dominant type of clay materials
mineralogy
434
mean annual soil temperature
(MAT) measured at 50 cm from surface
temperature regimes
435
number of days when soil contains
available water during the period when soil temperature
at 50 cm below the surface is above S°C
mositure regimes
436
used for differentiating soil order level
diagnostic horizons
437
a horizon that forms at or
near the surface and in which most of the rock structure
has been destroyed
diagnostic surface horizon (epipedon)
438
dark, soft, surface
layer; thick, greater than 10 inches; high base saturation of > 50%; mineral soil; soils formed
under prairie vegetation
mollic
439
like mollic but contains more than
250 ppm of citric acid soluble P205
anthropic
440
like mollic, but low
base saturation
umbric
441
Organic soil (20-
30% organic matter); saturated with water
histic
442
thin, light colored
surface layers that do not fit any of the diagnostic surface horizon
Ochric
443
man-made,
surface horizon that is greater than 50 cm
thick created by many years of addition of
manure
Plaggen
444
list of diagnostic surface horizons
mollic
anthropic
umbric
histic
ochric
plaggen
445
illuvial horizon
of clay accumulation
argilic
446
has an accumulation of
clay and humus to the extent of 15% of the
soil volume
agric
447
same as argillic
but with > 15% exchangeable sodium (Na)
natric
448
lluvial
accumulation of oxides of Al and Fe
(sesquioxides) and OM; red or dark red color;
only found in acid sandy soils; with high
rainfall; generally found below E horizon;
contains a Bhs or Bs horizon
spodic
449
very weathered layer of only Fe and Al
oxides and 1:1 clay minerals; low pH and not
very fertile (found in tropical soils)
oxic
450
light-colored, low % base saturation
and well-drained
sombric
451
a thin black to dark reddish pan cemented by iron manganese or iron organic matter complex
placic
452
subsoil cemented by silica
duripan
453
subsoil that is hard when dry but brittle when moist
fragipan
454
light colored subsoil
from where clay and free iron oxides have
been leached out
albic
455
accumulation of CaCO3 or Ca Mg(CO3h
calcic
456
accumulation of gypsum
gypsic
457
cemented by CaCO3
petrocalcic
458
slightly altered layer; not weathered
enough to be argillic; Bw horizon designation
or development of color and or structure
cambic
459
mat is <0
pergelic
460
mat is 0-8
cryic
461
mat is <8
frigid
462
MAT is 8°C - 15°C
mesic
463
MAT is 15°C - 22°C
thermic
464
MAT is > 22°c
hyperthermic
465
in soil temperature regimes Prefix "Iso" is used if mean summer (June, July,
August) and winter (December, January, February)
temperature differ by <5°C
466
measured in terms of the absence or presence of
water held at a tension of < 15 bars in the
moisture control section by a period of one year
soil moisture regimes
467
soil moisture control section in clayey soil
10-30cm
468
soil moisture control section in loamy soils
20-60cm
469
soil moisture control section in sandy soils
30 -90 cm
470
soil is saturated and
no dissolved oxygen (reducing regime)
aquic moisture regime
471
soil moisture control section
is dry more than half the time when soil temp.
at 50 cm is >5°C; moist for < 3 months only
aridic and torric
472
dry for >3 months and
continuously moist for at least 3 months
ustic moisture regime
473
soil is dry for < 3
months only
udic moisture regime
474
soil is continuously dry
45 days after summer and continuously moist
45 days after winter
xeric moisture regime
475
very young soil showing very
limited profile development;
entisols
476
entisols make up what percent of the world
12.5
477
young soil with..·
moderate profile development;
inceptisol
478
soil order that has limited change in parent material due to dryness
aridisol
479
young soils with little
profile development; presence of permafrost layer;
gelisols
480
gelisol make up what percent of the world
8.6
481
soils with thick,
dark, soft surface; soils of the grassland
mollisols
482
soils from volcanic
ash and cinders; very light, low bulk density, earlystage
secondary minerals
andisol
483
andisol make up what percent of the world
.7
484
acid sandy
soils with thick E and red; Bhs, ochric and spodic;
subsoil has accumulation of Fe and Al oxides,
humus and amorphous clays
spodosols
485
soil horizon with argillic B horizon with
high base saturation; fertile forested soils with
ochric and argillic
alfisols
486
soil horizon that has the B horizon has
high amount soft clay but low base saturation; soils
more weathered than Alfisols
ultisols
487
highly weathered soil with
B horizon containing mainly 1: 1 Kaolinite clays
oxisols
488
shows large
cracks upon drying due to dominance of
montmorillonite
vertilsols
489
organic soils;
peat soils, organic material
histosols
490
undecomposed to slightly decomposed
organic matter in waterlogged areas;
peat
491
highly decomposed organic matter
muck
492
good land that can be cultivated safe and
extensively to most crops with ordinary good
farming practices
class a
493
good land which can be cultivated safely
using easily applied conservation practices
class b
494
moderately good land that can be used
regularly for cultivated crops in good rotation but
needs intensive soil conservation treatments
class c
495
fairly good land that is best suited for
pasture but which can be used for agricult□ral
crops in good rotation provided intensive ' 5oil
conservation practices are applied
class d
496
land that is flat but is too wet or stony
and therefore more suited to pasture or forest!)'.
class l
497
land that is too steep, eroded or shallow
for cultivation of regular agricultural crops and is
better left to pasture forestry
class m
498
land that is very steep, er-oded, ro□gh,
shallow or dry and is better suited to pasture
forestry if handled carefully
class n
499
level land that is wet most of the time
and cannot be drained economically; best suited tor,
ponds or recreational areas
class x
500
land that is too steep, eroded, barren and
rugged and should be left for wildlife or parks
class y
