Soil science written notes, Study notes of Soil Physics

Download Soil science written notes and more Study notes Soil Physics in PDF only on Docsity! 407 = thy 1 Qi] Descibe the Details structure of soll profile ak Dep Soil prolle ls sojl profile 1s vertco} sechon of soi! show Tn varius Fayer From the. surface to the unafacted parent fi. |. Mineral cone \_ colur Cecil body) | ep zone oF Elluviation i yam Zone of illuviahon L Unconsol idaled masetiod % [soi] Hovizonefy Ti is layers oF Soll aproximes| parelle| to the Soil surface diftesing iD properhse ¢ characteristics Fram adjecent layer below or about . (4) "0" Horizon f i) The ‘o’ group is the organic hotizone which 1g Form and the Heavy surface of the Minerals | iip at developed From the plant ¢- anima] residyes iil} this present in forest Areq ¢- absent in Mineral soi] ee a on  iy) Eb ig divided Into three Horizon - a) Oj; ~ less decormposed Mateztal b) OCe- Medium decomposed Matetial J Ca ~ Highly decomposed Maleeial, (2) |['A’ Horizone- i) Ub is presen in Gurface Soi] ii) th ig called as topmast Mineral Hor zon i} TH Contain decomposed organic master. Iw) The surface and it is characteristeg ag zone ef washing Our fh an marxinurn liching TH is dark in colour, | eS Horeanep iy 14 is present in Sub- soil ii} This Horizone Ate the cone oF mateticadg Such ag iron , Guminium oxide and Silteek pit Frerg about Horizon, iil} Th is datk in Colour iv) Lt ig called accumulate Hortzone, 4) Lic’ Honzoneb> i) Th is developed by uncangalidated parent Material i) Ut formed Fram below the solud iii} This Hotizen tg oulside the zone of Major biologic activities. iVA If may or may not be the Same ag ine. parent Madesial, (S)|"E" Hotizone fb . | i) Ty is called Jeaching Honzene i) Silteake clay, fe, £ Al oxide leach ouk From, His Hoxzone Wi ct is Ighbin colour.  © | (@) Redy ction -> -~ the process of removal or loss of oxy gen] is called Reducton, - Ibis eqyally tmportant fn changing colour of soi] +o grey , blue or green ag Ferte tron ig Converted to Ferrous lion carnpound &g 2Fed, +0, — > 4Yfe,o Ferric oxide OxyGer ferrous oxide. catbon dioxide When dissolved fn Water jk Forres carbonic acd, 2 20 + CO ——> FCO Ander Carbon) car bonic oxide. acid. The carbonic acd or Carbonated Water Stacks roany rocks and minerals dno .bringg them into Solukon. Ca COs + Hy COg ——> Ca CH CQg2o_ Caf cite. . C slightly Soluble ) 4 carbonic caldup biearbon ale. Read G8] Define. Rocks 4 classificaHon of Rocks. => Der | Rocks +» this an aggvegate of mineral maker 4 composed of obe of morte primary or Secondary minerals i i Rocks may be jeined as the mixture | minture OF uo oF More Minerals © i  Rocks I ia r, : ee Tgheous rocks TZ] Sedimentary racks | Melamorphic, Rocks. a) Insitusive or a), Prenaceoug~ _plwonic b) Ar glia ceous ~ a) Dynamo 6) Extrasive ot q.cakcareous — Metamorphic | ~ Volcanic. d} Car bohaceois ~ b) thermo __ volcanic. a a) Siliceous ~ Neer ) precipitated ed ro Apreciprared = SN Shreonphic! @ gneous Rocks > / - tis formed by the moltan mass cooled} consolidaked info Solid rocks [6 Calfed “Tgneous Rocks” ~ Igneous Rocks ceniaining GS". th Cathy ctust 4 about (6 Km Hick _ ~ They mostly Consist of pHmary minerals eq Quartz orca, eldspar. | Taneous Rocks | | I a 4 D Based on Mode of otgin 23 Based on mode oF ee chemical Composit” ap Lnstruchye ~ ree (platanic) Solt'di Acation a) Acidia granite +akes plare frmodrare sandstone the eaHth eg granite 67-75 fy silicg b) Nyctral ss-6s% b) Extresive ~ C volcanic) solidifathon silica takes place on the ¢) Basic 40-§s */, | Surface of the earth a SINCQ. e294 Besar -  (@® sedimentry Rocks > y Wupes £0 tin ahHon stages-—> i) Weathering | it) Hrangpo rbahon ni) Oeposiken or Sedimentation iv) Diagenesig +e transformahon oF uncongeli— dalled Sediment Rocks. Ri_classificahon oF sedimentry Rocks — | 4) Arenaceous rocks -DIt Consist of coarse patticle SH crhey are, light usually granwdr ¢ poraus ii} €:g Sandstone, Conglamercde. 2) Brgill aceous rocks— 1) Th constst oF small size patkd FT THEY are light 10 dark thickly Larninabed struchire. til) @-q mude stone, shale. 8) Caledroug focks — 1) It consist of calelum car- banake 4¢. magnecdun carbonate ti} e-9 timestone , dolomite D carpoPeceolis Tocks~ TH Formed form decom pasins vegetation under udaerobic conditon mainly consist oF Carbon | fi eg Coed , peak = S\ Silficeous rocks — i) They are of organic. engin or Lave been farmed From parts | of yoinure Plant animals, | eg Diatomaceous eatth, &) preciapitabed rocks ~" . They are. mainly deposits, Formed as rock, mmasses » by Cooling avaporadton es TY PSU | rock | soutks . , | t @  0D fundamental pedogenic processes—, @) [RurtBcabion -s- r+ is the pracess of decomposition of organic Substance Decomposition oF organic mater 1S Complex proceas - The BacieHg cb Fungi - breale down the. Complex Compound. +o Porm Simple cormpound called VHumus” This Process 15 cuted Humihicaton, @fEluviation Ty T+ ig Mobilrzatjon + transto caljon Cwashing cub) of sult eg Ala0g% Caco, ~ in this process removal of salt jn Sei] Solwion by percolation of Water, ©] siuviakon+t x this process dissolved subs , are deposited in Soil Horizon by gravity force ,capiltary force , drainage ig called 45 Tihyvialfon @ [orizonalfonts If is the process of fotmaljon of layer in soil. — The formation of differ entiation layer ave due to Fundamental process, & lsyothests/ part oF the material formed Yt | “decomposition are synthesized “1 New Compounds. — The jroportant New compounds synthesised are clay rotneral.  6) Deline Soi] survey 9 Types oF survey f tks | = nef [Sai STVeYP. soil survey is essenticty To portance, oy Bruidy and mapping of Soils Pr thelr noburad Env ronmer} > Frypes oF Soll survey] (i) pelailed survey — (4) Reconnaissance, survey — (13 Detailed —~ Reconnassance Survey — Gy semi - detailed Gurvel — (1) Detailed survey »Elaberabe rocepping 1s done : demarcakng tHe ‘towest cate- gories of taxonomic + Mapping units. ~ pedones are examined and ° sampled for deained of the soil (@)_Recannaissance survey ~> — the mapping ig (ess eleborate $ jarqer areas are surve yed rapidly — this Survey usePul in NeLO regions for qenerel planing (8) Detailed— Reconnaissance Survey 7 ~ They Constitute. element of bok) deballed 4 reconnal- ‘ ssance, SUrveYy (@) Semi -Deleiled suvey -7 - This survey CO MpHse very dekuled study of Some, Selected sft ps. KTmportance > D To get information about Sejj 9enesis W) To gk inPermetion about Soil Yesources © ne : { 14 nT ToT Plane keattyc} usecd= FRIOU TCS OY FE  ag] What do you means Lon Exchange. Explain =="the fmportance of cation exchange fr sof]. > Pero ELON EXCHANGE} Lt Is the surface prop " Of the soil colloids, This exchange, of jans bet? soi| Solution 4 the jong. adsotbed on soil colfofds xe | Emportance OF Cahoon “Exchange Ip So} | = CA) zetw potentHeas — (29 Valency of long — @) Size and degree oF Hydrahan oF TON @ Concentration eF fons in Solution = (4) Zeta, polepnhalls>.the. (rapidity of exchange depends “pan zeta potenHal — Hrgher the cela potental of the caHon more easily ih replaced, (® valence oF long Higher the valency of the cation .greafer js the replacing Power of the fon ¢ pore if resist replacement. @|_Sizeand degree of HydraHen oF FON fs - cations Have sane Valency the rapidly dcase of ex change increase With effecHh ve size. © Concentralon ef Joos in Soluhon by ~ cation exchange . also depends ON ConcentraHon of fons ts replacing SBolukon Col] 301) Greater the. GoncentraHon of CaHong,  alo peffne Soi] Colloids and types of Sol] cariaids => per sdi] colieids [> The soll colloid 1¢ a matesiel made up oF organic oF inorgans patticles less than ©-00] mm ciameler. _ x [Types _oF soil caljoids | > | {soil colloid [> J | ]\Foorqanic Colloid at] [organic colloid | a ro) fe em SI ‘Humds jayer Silicale clay Fe¢Aloxide —_Alfophane $ ray Other cendtp hous mineroy OL. em | Semechic ia . @ orioe | Montmen iNienite ~EHFe ~ kaolinite, Saponite — vermiuwite —~_Haulloysite.. | x] Lnerganic Soil Colloid > | Layer Silfea-e eclay— 1) TH lg a crystaline Nadute. NW) This @ layer Kke structure means leaf ¢ platelet like struckite, Hi) Ibis a mostly presenk In temp rake. ‘+ tropic dreg iv) Divided into +w6 Hoxicontal sheaf a) Dominated by Bilicon Coi4t) ~ Tetrahedwn &) Dominaked by Bl Ht mgt — Octa hedron, tet rahedran ¢ actahedron. @ Tetrahedron @® octahedron R S104 i one Silicon aber) Surrounded by 4 oxy4e) ator nded by six oxygen 1) four Sided corfigrd® BH group 1 ORGGED OF it) siica tetra hedva tide NW) tt gives elyht side together by oxygen anion Con Rig ration to Porm Febrahedta) sheaf - iW) ocdabedra linked” : +09 ether - Horizontally to Porm cetahed raf Shed. Gal] Define Minera). classify the. minerals Based on Mode of origin 4 * | e pefe Minera] by Mineral are Nakurally oceuting 7 - Inorganic Solids, homogeneous Substance . composed of atoms having 66 cdveady on a reguar avrangermenh with definite chemical composition, * [classifi cadion oF Mineral s|- Fi] Based _on Mode of origin (formation) — @]_Based on Quanity — cL Based on specific’ Gravity — B] Based _on chemical Composition ~ [8] [Based on Mode of OHafhls iW _pdroary minerals +» Tt formed from cry stal f - zaHion of Magma. — This oHginal Cornponent of Rocks »  eg G @ugez. @ Heldspar RB) Mica. | hy Secondary oinerals | ~ tT formed due to alteration oF pimary minerals, 2 e9 (@ auarts Q clay Ckaolinite @ calcite Gy Setpentine Miel Give the Therma) properties of sol], => Thermal Properhea of Soil. (A) specie Heak -— (29 Heat Capa city ~~ (3) “theenmal Conduchvity — (4) Therma) diffusivity — {4| [specific Heafts. — a+ may be dfined as the amount of Heat required to false the temp | oF i gro .of subs by fe. — Tt ts expressed In cal / — The speciiic hear of dry sol | CO,2 Col / gin) —motst soils are Cooler due to their High specific Heap. also due to the Heak energy spent in evaporalton oF Soll motsture. specie Heak of Water — | cal/ am Om — 0-467 | \ i | clay 0.22 | and a4 Hummus ~ 0-4 g i (2) [organic matter} > High organic mater more wt the wiaker retention in soll (4) Density of soi [}> Higher bulk Density of soll, lower ie the water Content (6) [Tempratire [> coftjer the ternprature higher 19 the. moisture retenHon, (e) [Salk Conten Fhe more the Salt Content in the Soll, less i the, water aval lable to plant @) epi of sil fo more the depth of soll, mare s the wakr avalable to thee plant (gy [Type oF cl the att type of cleuy increases the. water rekepHon in the Soil, as | Give the composition of plant resicduces and explain rele. oF organic maker in of Soil properties > x [composition oF plank Residuces Fp () Moisture content oF green plant tissue VaHous Froro 60 +090 Percent with an average TS percenr ‘ @ the dry matter is mostly carbon eine oxy qen with jess than to percent - (3) organic forms of essenHaf Nutrient euch 4g nitrogen phosphorus, poHesiuny Galeium ¢ Sulpher: ) IF So)) Porosity ig reduced belous Jo-fay.so 7 sol CS) Root resujred a} least Sv oxygen in soil ain er) [compe ound | percentage | C19 __carbohydrales _ oO (29 Sugar — 1 to5 (3) Celiwlose — 206+toBa (4) _Hernicelj ose — 10t028 (52 proteing — 4 015 (¢), Fact, oils waxes tepning — 1 to 8 C79. Lignin’s — 10 to3o, *% organic. Matter a —eorganic maker addikon and cropping fnerease the level of COg_ ip soil Rit. = carbon dioxide procduchon being product of Biotogical ack vities, Gta i; Variug Forme of- sei| waler and explain brief Fretd capacity oF soil > [Fesg oF rear p> (1)_Field capacity (2) _permenent wilting point (a) Avalable water cepacthy 4xmarimurm helding capacity (5) _moisture equivalents. — Cen, shiek ont coolsture . 3 iG CD [ Field copacityps pAPler applicaHon of walter 1 the Soil. all the gravitatona water has drafned out, tho | The amount of water held by | -+he Soi | at Phis shege is 13 Calledt! ee Ficld_capactiy.. $ :  = His capacity of the soi] to retain Waser against force of gravity — The Amount of moisture held of Fret capacity is available +o plant - (2) [permenant wilHog pont /sssilting eo ef Ficlets —~-+the percentage of water held by the Soil of wilting point 5 cated a3 permenant wilfing point - @® [Avaulable iWeder capacity fb . The amount of wajer requree] To apply +o a Soil at the wai Hing point to reach +he Field capacity 1S caljed available waen _ the water supplying power of Soils 1S related jo the cumount af avartleble woter a saj} can bald, (4 Maximum Holding capacity Ly —~it 7s also Kno®N as max} mur retentive capacity — So}} moisture tention 1a very lo | roo th tO 'Aooot® OF an admosphere ‘av pe 1 too, (S) [sticky point rpo}sture-[-s _ xt! represent the moisture content of sail ar which tt no Longer sticks +o a forergn abject: _- I+ is moisture Content of which it no Longer sitck -+to foreqn abject A stage ab which Soll remains Frakbe,,  8) _Nittificaliod 3 The con¥ersion of ammonia to Nitrate (N03) 1 Called ag nit cade ON, _ Autotrophie bacteria involved tn -this transPormal on, () the Ammonrdng microbes includes both ardobia popwation, ave penne Soil & Desctibe the structure of Ea th, <3 pet soil} soil may be deined. as gq atnamic naturel body on the surface of the earth (n which plant grow Composecl minered , arganje matetal , ye Earth consist of (1) Atmosphere — @) Hydrosphere — (a) Utbosphere. ~ (4) plosphere.. — (4) [Atmosphere Fs ~ {tig oubermost- layer oF earth Jt extends From su rface oF the. earth of about 620 km, ~ TH 1S lighter thao Hydrosphere. __ Tt consist oF mixture of gassed. weg N,0,¢ Composition OF pjimasphere (i) Nitrogen — 760% (> oxygen EO (3) Carban clioxide 0:03°4 (4) other gasses — O'9d7 the atmosphere cont buey 0-03, by “4Gh) of earth  (2) [Hyarosrhee}s | | —~ Th is layer of water sutroundsing the (fHhosphere. —Tt present in the From of seq ¢ oceans Th oceupies nedriy 7Oy. of the, Surface oF earth, (3) [ Brosphere}-5 —the potHon of the lithosphere Which Hse above fhe seq water ig visible te us and Which fs Known as ‘Land! _ ‘The biosphere. consish oF living organist like man, animal , micro- organtom , (4) [ERosphere|s —Th is fhe loner most bedy Wi kbin the gassey _¢ wake envelope. — Tk consist 90 pottan, prnosphert. y the upper Cooled sealid surface i} Toner hob ¢ molten mage Biosphere . Hydrosphere. Uthosphere ower layer  x [Composihon Of Earth crust] —» TElement | Mineral Oo 3 4] OL, C1) Fleldspqy > sey. (4 Si > 2R0Ey: (2) Hornblend > [cy, (3 Al > Si ley. (> Guattaz +> 1B. (0 fe > 484+, (4) micg ys Sy, © 43> 350 + © ley —» 1 y. | Gls] physical properties oF soils. | > Pphysicad proper Ha of Soils. [_ (Ciy_soil texture = @) Soil structure» (a) _ surface, agreq > @) sot] density ~» © _Seil porosity (6) sei) colour, (D_Soll consistence (@)_Soi] pir > (4) Soi] Waler (1) [Soi] Texturebs, | ~ soi] texture refers to the relatve propotHon of partdes oF Sep arakes of vatius sizes in a given Soil, the relative percentage ok Sand gilt and clay in a soil, Ca [sei] steyeture|, The @trangement and orga - ci mzahean of prima and Seto nda prhical tn Soy] rnass Known a4 Soil structure li) .Crood Joarny soi] contain about 38 +0 80 pereenr ei. iit) They are intermediate bebwepy sandy soils and clay soils, VA tn loam Soil 4yood liHh is obtained easily vy They are pantally Suited to ewery Wind of crop such a3 Wheab, maize , Bice, sugarcane etc. Q20 | The General properties oF soll colloids > [properties | (1, Brawnian movement — (2) Electrica) charge — (3) Non permeability — (ay_Dispersion ¢ Fl ocWaton — (Size. — (a)_gurbace Areq | (M_cohesion ¢ Adhesion — | @_plastielty (4)_AdsorpHon (to1_ewelling $ shrinkage — | (CD \ Brawnian maverent Ls | Ca}ieida} portical are 10 be canted: ConHnue rnoton by aseiflahon, —This movement is mainly respo— nsible for the FloceJahen, —The smoler the particle rmore | rapid mm overs | [ i  cao [Eleahieal charge] | — colloidal -patticajes often have some, posihve & Some, -ve electrical chargé, i ee | @[Non permeability Ls — Colloids ,are Unable te pass : “through a SZeml(merbeable Membrane. , | (4) [size bs | — They gre seen taking thelr photograph With <lechran mics cope. — coflaid pattcle Size is fess than 2.00 mm in diamerer. (9 [are reals — calloids vert smalf in size Oppose | farge externa} surface Area, | (© [Cohesion £ auhewon L, i} Cohesion -» “the tendency of oe] — partic +o off ck toqeHer that are Amilar in Naku. | i) Adhesion — The dendency oF Colloidal ' patide Sticking fo other saab eg UIGPEL . — Hydrogen bonding bey clay sur€qce f wae responsible, For adhaion, (D [rlastelty Ly oe | ~ Soi) cantaining more than 15x clay exhibit. plasticity ; ~_plastcty is due te ploke - like clay pattcls yo  “ell Explain the significance. oF sd}| pit — ~> [significance of Self pH (i) In Neutral SOs — — Most plant perform welf Some plants species required Acid of alkaline reactoo legumes n weal fo slightly alkuine sol] (u)_Nuwelent aveulability in soi] depend on its PH ~ At lao pl Fe mn are more soluble and avaifable more so tha they oe Prove To be toxfa to plants aves lobility - of mo,04,p dec reqsed QU) anfluence activity of microorganism which Th turn tntience decomposjton process oF oy mettter and ve Tet) I by oF Netigiente (iw ToFluence ig need for Rabilreer (vj Influence soi] of the ehucure,  x [Types oF Waker Exesfonfs / classification, —> o Cy_splash Erosion — (oy sheet Erostod — (> ill trosion @)_Guly troslon — (5). Slip Exosio) Ce) stream Bank “Erosion — A) Sea shore troden — (D | splash EPOSION) | ~ the, soils most readi ly detached ey raindrop splash Crosjon are Ane sandsand silts, — mast Sails of Finex texture, Such a5 clays dod clay loams, are nap readily detached beatuse of the strong forces oF Cohegjon Aggregated , — When they are very wet or tilled excessively with only mea qer additions “of organic matter. beFine soil aeration, Factor affecting of ~~ gai] airator) ¢ Give ifs Importance. pee? [sol] _deration } The. constant meayemen} of airy in the soil mass resulng in the renetow) of gasser ts called“ soi] qerakion y  y [Facdor affecting soi) aeration b> Cb Nature & condition of soi] (type of crop (a,Microbial acHvi (4) Seasonal variation () [Nature 4 Condition of soil] 3 — Quanity ef Og is es in sold dy thay cbmosphetle ayy — Th depends upon the depth of s0}| surface layer - 9, Is Higher jower layer — go is lower. (2) F type oF crop ry — plat roof requirtel 0. Which they fake, From sol] an reduced the concentrion oF Oz in Soi} alr — cropped soi] contain) Mere (do CONC, han Folfow Jand, ~The mico-organism™ In so}} require on + They take RUM soll aq — Decormpasitian of orqd nic matter. (ay [Seasonal variations =the quantity eF A is usually Higher in ay seaion than raj y SUN — High femp during Summer sean DCO. mero ~ organism activity, rault Higher prod  s& ctrportance of soll ar en plan} growl 3 (D_plant 4-coof growth (2) Microbial popwatfon d activity + (3)_ProducHon of toxic substance — ()_Wakr ¢ niubtient absorption —» (s)_bevelopment eF plant diseue > S23] pebine Humas 4 propertis 0 of p Harms, 5 Funclion rovcure, of dark brown amorphas Caffoldal, organi¢ subs Rromg—mierebied Fre. Developed From microbial decompositien +. synthesis. — The Hoy Cofeidal. Humys partcley are composed of (59% ,HO-SY: , 0 BTY. N-sy. — the surface. dre of Hummus fs very High than the silfcade cl ~ The collojda) surface. of Hummus ate “Ne, charged, — The CEG OF Humys is ISO-30n Mmey/ rg is more. than Silicoe c} —The water Holdin Capacity ef Hamat is 44es time more than Siliade c — Hummus fs qood eFRech an 999r 270 ne Fo rater) — Humus Hay dark brown in colour — Tt has amorphow in naktte, tT