Experiment 5
Soil Characterization Characterization K. Draheim, B. N. Estrella, K. M. L. Garcia, L. Guillermo Department of Biological Sciences, College of Science, Universit of Santo !omas, Espa"a Street, Manila #
%$Key words:
Summary
&ermea'ilit
Soil can 'e characteri3e* ' its structure, color, consistence, te(ture an* a'un*ance of roots, rocs an* car'onates. !hese characteristics allo- scientists to interpret ho- the ecosstem functions an* mae recommen*ations for soil use that have minimal impact on the ecosstem. 4n the e(periment, the percent p ercent composition -as compute* to 'e #$5 gravel, 675 san*, 685 silt, an* ##5 cla. 9ith 9ith the use of the soil te(ture triangle, soil te(ture class -as *etermine* to 'e loam.
&orosit Sieve
I. Introduction
Soil is the mi(ture of minerals, organic matter, gases, li)ui*s, an* the countless organisms that together support life on Earth. Soil is consi*ere* to 'e the +sin of the Earth+ an* interfaces -ith -ith its its litho lithosph sphere ere,, h*ros h*rospher phere, e, atmosp atmospher here, e, an* 'iosph 'iosphere ere.. !he propert properties ies of soil soil are *etermine* ' environmental factors an* five *ominant factors are often consi*ere* in the *evelopment of the various soils climate, parent materials, relief, organisms /fauna an* flora0, an* time factor. Soil is the en* pro*uct of these factors interacting over time. Different soil tpes e(hi'its *iverse 'ehavior *ue to *ifferences in micro1morphological, morphological, phsical, chemical an* mineralogical properties. !hese variations are *ue to variations in soil forming fact factor orss an* an* proc proces esse sess opera operati ting ng on *iff *iffer eren entt parent parent mate materi rial als, s, un*er un*er *iff *iffer erent ent clim climat atic ic,, topographic, an* 'iological con*itions over varing perio*s of time. !here are a large num'er of *iff *iffer erent ent soil soils, s, refl reflec ecti ting ng *iff *iffer eren entt in*s in*s an* an* *egre *egrees es of soil soil form formin ing g fact factor orss an* an* their their com'inations. 2 hori3ontal laer of the soil, -hose phsical features, composition an* age are *istinct from those a'ove an* 'eneath, are referre* to as a soil hori3on. !he naming of a hori3on is 'ase*
on the tpe of material of -hich it is compose*. !hose materials reflect the *uration of specific processes of soil formation. !he are la'ele* using a shorthan* notation of letters an* num'ers -hich -hich *escri *escri'e 'e the hori3o hori3on n in terms terms of its color color,, si3e, si3e, te(tur te(ture, e, struct structure ure,, consist consistenc enc,, root root )uantit, p:, voi*s, 'oun*ar characteristics an* presence of no*ules or concretions. ;e- soil profiles have all the ma
#.0 !o i*entif, measure an* recor* the hori3ons in in a soil profile at a soil characteri3ation site site an* its particle si3e *istri'ution. =.0 !o *etermine the particle si3e *istri'ution *istri'ution for each hori3on in a soil profile.
III. !ethodolo"y
!he follo-ing materials -ere use* in the e(periment triple 'eam 'alance, tro-el>shovel, an* sieves. 2 shovel -as use* to scrape soil off the profile. profile. !he soil sample -as then initiall initiall -eighe* then sieve* in four *ifferent pore si3es. !he four soil samples -ere then re-eighe*. !he percent composition -as compute* an* a soil te(ture triangle -as use* to classif the soil sample te(ture class. Figure 1. Sample picture
#. $iscussion
Soil te(ture is the relative proportion of san*, silt, an* cla in a soil sample. 4t is critical for un*erstan*ing soil 'ehavior an* management. 4t is *etermine* ' the si3e of particles in the soil. Soil te(ture te(ture affects affects -ater1hol -ater1hol*ing *ing capacit, capacit, permea'ilit permea'ilit,, porosit porosit,, soil -ora'ilit -ora'ilit,, an* the a'ilit of plants to gro-. !he si3e particles that mae up each tpe of soil *etermine the si3e of the pores 'et-een the particles. 2 pore is a space in roc, soil, or unconsoli*ate* se*iment that is not occupie* ' mineral matter an* that allo-s the passage or a'sorption of flui*s. &orosit is the percentage of roc or soil that is voi* of material an* thus can 'e fille* -ith -ater. !he larger the particles maing up the soil, the larger the pores 'et-een them. 2n* the larger the pore space or the greater their num'er, the higher the porosit. San* is ma*e up of particles -ith *iameters ranging from $.$7 mm to = mm. Because of the si3e of the particles, san* feels gritt an* *oes not stic together in a mass unless it is ver -et. 4t has fe-er nutrients for plants than silt or cla. 4t has pores 'et-een san* particles that allo- free *rainage of -ater an* entr of air. San* soil has large particles -ith large spaces or pores 'et-een them. !herefore, -ater *rains through san* soil )uicl. San* soils *o not hol* or retain -ater ver -ell. 2s a result, it is not goo* for gro-ing most plants. Silt, on the other han*, are ma*e up of particles -ith *iameters ranging from $.$$= mm to $.$7 mm. Erosion ' glaciers are often responsi'le for formation of silt. 9et silt *oes not stic together an* cannot mol* into *ifferent shapes. 4t has smaller particles an* slo-er *rainage than san*, -hich ena'les it to retain more -ater an* nutrients for plants. Lastl, cla is ma*e up of particles -ith *iameters less than $.$$= mm. 9hen mi(e* -ith -ater, the small particles of cla *o not settle. Cla is ver po-*er -hen *r an* ver stic an* slipper -hen -et. 9et cla can 'e mol*e* rea*il into an shape or ro*. Cla s-ells -hen a**e* -ith -ater an* shrins an* 'ecome har* -hen the -ater evaporates. &ore spaces 'et-een cla particles are ver small. 4t has a tremen*ous a'ilit to hol* -ater 'ecause -ater an* air move ver slo-l through cla. !o *etermine the te(ture of the soil sample, the percentages of the three soil particles -ere
*etermine*. 4n this e(periment, -e o'taine* ?.7?5 gravel, @8.A?5 san*, 8.#=5 cla, an*
[email protected] silt. Using the Soil !e(ture !riangle, the te(tural class -as *etermine* to 'e loam. Loam is a mi(ture of cla, san* an* silt an* is the 'est soil for gro-ing plants. Because loam is a mi(ture of *ifferent soils, it hol*s the proper amount of -ater an* provi*es all the nutrients plants nee*. Since loam soils have *ifferent si3e* particles, pores are varing in si3e. 4ts *rainage is slo- 'ut still -ell *raine*. 4n other -or*s, it has v aring porosit an* permea'ilit.
%e&erence:
2mmons, . !., Blair, ., Comeau, 2., Lu, C., Morris, M. 9., o'erts, C. /=$#$0. 2 Comparion of !hree Soil Characteri3ation Metho*s on a Soil ;orme* in San* Glacial ut-ash. Proceedings ut-ash. Proceedings of the Annual International International Conference on Soils, Sediments, Water Water and Energy. 15 /=%0, 15 /=%0, pp. @A$1@%%.
Kalpage, ;.S.C.&. /#8?60. !ropical SoilsF Classification, ;ertilit an* Management. Ne- or St. MartinHs &ress. Kang, B.!. Spain, .M. /#8%A0. Management of lo- activit clas -ith special reference to 2lfisols, Ultisols an* (isols. Proceedings (isols. Proceedings of Symposium on Lo Acti!ity Acti!ity Clays "LAC# Soils. Soils. pp. #$?1#@#. Mitchell, . K. /#8?A0. ;un*amentals of Soil Behavior. ohn 9ile an* Sons, 4nc. Uut 2., 2pan 2pan U. S., U*oh B. !. /=$#60.Characteri3ation an* classification of soils in steep si*e* hills an* sharp1creste* ri*ges of 2-a 4'om State, Nigeria. $et Nigeria. $et %ournal of Agricultural Science & /=0, pp. 7$17
