05/23/2018
Compilation of the Discussion.
READ ME WITH UNDERSTANDING!
#1. The most effecient orghanic matter decomposers under acidic soil condition are the.
Fungi- pag acidic Fungi na ang sagot jan.
#2. Which among the following soil organisms are acid-loving?
Fungi- pag acidic fungi na ang sagot jan.
#3 the most abundant elements in the earth's crust are :
(O, Si, Al, Fe, Ca) but the three common elements are O, Si, Al. Oxygen tops the list in terms of abundance.
#3 net nitrogen immobilization in soil occurs if the C/N is:
Greater than 35:1
Carbon: 35 and Nitrogen : 1
#4 the root nodules bacteria belong to the genus?
Rhizobium- Rhizobia are unique in that they are the only nitrogen-fixing bacteria living in a symbiotic relationship with legumes. Common crop and forage legumes are peas, beans, clover, and soy. The first known species of rhizobia, Rhizobium leguminosarum, was identified in 1889, and all further species were initially placed in the Rhizobium genus.
#5. Individually, which among the following soil organisms have the least biomass?
Bacteria- there are two commonly soil organisms happen during the decomposition of soil the fungi and bacteria as you notice the fungi has it's 8000 kg/hfs biomass than bacteria 2000 kg/hfs among the two the least is bacteria, why not protozoa it has least biomass? because ingest food through oral openings.
#6. Ammonia volatilization NH4+- bearing fertilizers is not by which of the following?
High CEC or Cation exchange capacity is a measure of the soil's ability to hold positively charged ions. because the vulnerability for NH3 volatilization from fertilizer is largely. ammonia rapidly reacts with the soil water to for nh4.
#7. what is CEC.
Cation exchange capacity is a measure of the soil's ability to hold positively charged ions.
#8. methamorphism is caused by?
alteration of the composition or structure of a rock by heat, pressure, or other natural agency.
#9. the mineral supplying P is
CA>>>Apatite- is a group of phosphate minerals.
Others>>>
feldspar- is the name given to a group of minerals distinguished by the oresence of alumina and silica. an abundant rock- formming mineral typically occuring as colorless or pale-colored crystals and consisting of aluminosilicates of potassium, sodium, and calcium.
talc- or talcum is a clay mineral composed of hydrated magnesium silicate with the chemical formula. some talc may contain the known carcinogen asbetos, therefore it should be avoided in powders and other personal hygen.
pyrite- a shiny yellow mineral consisting of iron disulfide and typically occuring as intersecting cubic crystals.
#10. the root-nodule bacteria belong to genus
Rhizobium- Rhizobia are unique in that they are the only nitrogen-fixing bacteria living in a symbiotic relationship with legumes.
#11. The most abundant elemeent in the earth crust?
Silicon, next to oxygen and its after is aluminum.
#12. the question that are not numbered won't be entertain.
#13. Zone of accumulation?
CA is B horizon also called zone of illuviation, from the word itself "elevate".
#13. the movement of heat in the soil is called?
the transportation of the heat by a fluid in motion is called conduction followed by convection, in other books the first is convection.
#14. algae are considered as
in general, the correct answer is photoautotrophs. the light energy is then converted into food molecules in a process called photosynthesis. some sample of this is seaweeds the green algae.
#15. Rhizobia are generally associated with nitrogen fixation in
>>>>>>"Peanut"Viscous means sticky, gluey and syrupy. So if something is viscous, you usually don't want to stick your fingers in it
#20. If soil moisture content is 50%, field capacity is 40% and permanent wilting point is 20%, the amount of available water in the soil is;
CA: B. 20%
> Formula ( AW= FC-PWP)
AW= 40%-20%
Aw= 20%
#21. The color of a soil indicates some chemical conditions
CA: A. Dark or Black color indicates high organic matter
#22. Type of soil structure that is best for growing uppland crops.
CA: C. Crumb
> a soil condition suitable for farming in which the soil particles are aggregated into crumbs. A type of soil structure in which the structural units or peds have a spheroidal or crumb shape. Crumb structure is often found in more porous than granular organo-mineral surface soil horizons, and provides optimal pore space for soil fertility.
#23. Type soil sructure of a compacted plow soil is;
CA: A. Massive
> Massive means that there is no arrangement of soil particles into "real" structural units. This is often found deep in the soil or when the soil particles are cemented together.
#24. In general soils at the summit and shoulder develop horizons.
CA: C. fastest
#25. A condition that re**rd soil development.
CA: A. cold and dry climate
#26. The development of E horizon is often accompanied by the development of the zone of illuviation which is labeled
CA: C. Bhs
#27.Microorganism w/c do not require oxygen are called?
CA: B. Anaerobes
> an organism that grows without air, or requires oxygen-free conditions to live.
#28. whicf the following microorganisms is very sensitive to potassium level in soil and therefore useful in diagnosing potassium defficiency?
CA: C. Aspergillus niger
> is a fungus and one of the most common species of the genus Aspergillus. It causes a disease called black mould on certain fruits and vegetables such as grapes, apricots, onions, and peanuts, and is a common contaminant of food.
#29. Particle density is stable soil property, most agricultural soils would have particle densities close to this value.
CA: B. 2.65 g/cm3
#30. A soil with a bulk density of 1.3 g/cm3 and a particle density of 2.60 g/cm3 will have a porosity of;
CA: C. 50%
> 2.60/1.3= .50X100=50%
#31. A deficiency of this element will not enable a legume and its bacterial partner to perform nitrogen fixation.
CA: C.Molybdenum
> is a trace element found in the soil and is required for growth of most biological organisms including plants and animals.
#32. Pore-size distribution affects movement and retention of water and air in the soil.
CA: E. All of the Above
#33. Pore-size distribution affects movement and retention of water and air in the soil.
CA: A&B
#34. The study of rock is?
CA: Petrology
> the branch of science concerned with the origin, small-scale structure, and composition of rocks.
#35 & #36. Soil densities and porosities are affected by soil texture and soil structure.
CA: B. Soil compaction increases bulk density
C. Soil aggregation improves porosity
#37. The molten mass from where igneus rocks solidify from is?
CA: B. Magma
> hot fluid or semifluid material below or within the earth's crust from which lava and other igneous rock is formed by cooling.
#38. The parent material corresponds to horizon.
CA: B. Horizon C.
> is relatively unaffected by the processes of soil formation and therefore does not exhibit as much internal layering.
#39. The physical state of the soil as relates to plant growth as soil.
CA: C. Tilth
> is its physical condition, especially in relation to its suitability for planting or growing a crop.
#40. the sedimentary rock that contains clay minerals as one of its more important coonstituents is.
CA: A. Shale
> is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.
#41. Soil texture that would be best for growing lowland rice.
CA: Clay loam
> is a soil mixture that contains more clay than other types of rock or minerals. A loam is a soil mixtures that is named for the type of soil that is present in the greatest amount. The particles of clay are very small, which is one of its most important characteristics.
others:
> Sandy Loam- a loam consisting of less than 7 percent clay, less than 50 percent silt, and between 43 and 50 percent sand.
> Silty loam- soil containing not less than 70 percent silt and clay and not less than 20 percent sand.
#42. Soil texture class wherein the coarseness of sand, the smoothness feel of silt and the stickiness of clay are mannifested in almost equal proportion in a soil mass.
CA: Loam
> Loam is soil composed mostly of sand, silt, and a smaller amount of clay. By weight, its mineral composition is about 40–40–20% concentration of sand-silt-clay, respectively.
#43. the entry of surface applied water into soil is known as?
CA: A. infiltration
> is the process by which water on the ground surface enters the soil.
#44. this is use in determining soil color
CA: C. Munsell color chart
> color system is a color space that specifies colors based on three color dimensions: hue, value (lightness), and chroma (color purity).
#45. movement of water in the soil is known as?
CA: B. higher to lower total potential energy.
#46. the moisture content of an air dry soil is known as.
CA: D. hygroscopic coefficient
> the percentage of water that is absorbed and held in equilibrium by a soil in a saturated atmosphere.
#47. the hydrometer and pipette methods of mechanical analysis obey the
CA: D. Stoke's Law
> the law that the force that re**rds a sphere moving through a viscous fluid is directly proportional to the velocity of the sphere, the radius of the sphere, and the viscosity of the fluid.
#48. The upper diameter size limit of sand particles is;
CA: D. 2.0 mm
# The upper diameter size limit of silt particle is;
CA: A. 0.02 mm
# The upper diameter size limit of caly paticles is;
CA: F. None of the above
> 0.002 mm
