bn 1062

Un;wrs;,y of M;J5O\l,; Columbia, Missou,i

College of Agriculture Agr;cul'u",1 Expcrimen. S",<;on

Roso, L. Mi,dw,lI, D;=<o<

Saturation, Labile Pools, Distribution Coefficients for

Soil Phosphorus on Sanborn Field and other Missouri Soils

E. R. Graham alld}. H. Y ....

I

June, 1989

Acknowledgeme n ..

This smd~ was s"PP'>r<ed in 1'"" b~ II>< N .. ional Science FlHlnd .. ion.nd 'hr IA£A Th<: ""df on Mi • ..,..,i soil. and Sonborn Field was ton"ibmM from ,I>< Mi.sou'; As, icu[,u",1 upe,imenl & .. ion Journal St,i .. No. 849l.

About 'he Au,ho,t: E. R. GIlIh.m i. proksso< emeti,,,. in II>< Deportment c.r A8ronom~. J. H . Yoon i. an lAM Fellow.

CONTENTS

ABSTRACT

INTRODUCTION

MATERIALS AND METHODS , RESULTS AND DISCUSS ION l

SUMMARY • UTERATURE CITED • TABLES 6

FIGURES ,

R~search BuHetin 1062 I

Saturation, Labile Pools, Distribution Coefficients For Soil Phosphorus on Sanborn Field and

Other Missouri Soi ls

/J. R. G",1;am "nd). H. y,,,,,

ABSTRACT

A .. udy "' .. modo on 'hooil pboopboru. 1 ... 1. of sel"",ed plo" from Sulborn field .. d Othe, Mi."""i ",il. in rela,i"" '0 ,he f,,,ili,,,, '''''''m<n'', croppi"l! 'y.,.m •• nd natunl phoopho"'. le"eI •. Tl>e <nuh •• ho",N 'h" plo" 9, 13. 17, 311 and ~ we,e nOl ... unted wi.h phospboru. while ,t.: ..,its of pi",. 2. 10. 20 and ,h< ..,il. 0( Sa<PY, Ileul.h and Sharkey se, ies """t<: ",un,ed. Soil pOosphatu. r<>und in ,n. bbiJo pool .... • hown by di",ibu.ion rorffi<ien" and Sny. 'oogen ..... «b,ed to the «.,,,,,,,,",.nd mao'8<m<m of crop< on Saoborn field . nd the oo.u .. 1 phoopooru • .1 ..... 1 of Mi...,u ,i ",il •.

INTROOUCTION

Many poram:,e,., for ... I..ating soi l phosphoru, in relotion to crop grow.h have !xcn devised ,i"'e 'he Jxgin ning of modern ogr;cu ltu,e. MO<ll of th<$e param .. e" have shown a close rel ationsh ip wi,h crop growth ;n li mit<d goog"'phic soil areaS. Sucre .. has nOt been complete bocause up.ah from ,he "'il depends On ~",I facro": 'he amOUnt of total available phosphotus . the concentntion of P in the "'i l ,olu,ion, the diffusion Nte of P in ,h~ soil and many biologi",,1 facto",

The I moum of available nutrientS in the soi l i, sometim<$ rcferrtd to as tile Il bile pool. Bowman., "I. (4) repor<<d 'hot ,he b bile phospho'us in soil. d .. ermined by the isotopic exchange m.,hod, gave the highest co,,"ladon wi,h total phospho,us up ... k~ by crop<. as compar<d wi .h Ol~n. Colw. lI and resin-P d~~rminlt ion,. report<d by Beckwith m.

M.ny a"fpt. ble methods have been devi~ for det:rmining and ""kulating usable pool. of p~osphorul, and phosphorus concen,ration in the soil ",Iu, ion and relatillg these determiru,;ons to phosphorus ~r<i ! iltr ,equi rM fo, adequate plant growth. (2, 3, 6,8. 10, 13, 14).

Th~ objective of this "pdy W2iI ro relare long time ft, tili:e. soil flcatmenlS On SOme Sanbo,n Field pl()ls and rome high phosphorus Missouri soil! !O ,h: phospho.us $OItutj,tion of ",ils, tile dimibution coemci.nt (intensity factor) (Kd) and t he silt of 'he usablt labile phospho.us pool.

2 Miuouri Agricultural b perimcnt Station

MATERIALS AND METHODS

Nine soil samples of M~xico silt loam (uuollie Och",qualf) wen: t.ken from ,he plots in Sanborn Field at the University of Missouri·Columbi •. Sanhorn Field wa.\

established in 1888. Two ,ampic'S, Shark<:y day (vertic Haplaqucpt) .nd Beulah loamy fine sand (typic Dy"rochn:pt), derive.! from Missi,sippi River alluvium, and one sample of Sarpy loamy fine $;>nd (typic Udipsammcnt). deri.,...! f",m MiS$Ouri River alluvium. wen: useJ fur romparison as soils more rhan ntl<"<J"ardy suppli..J wilh ·'availabl. p" as estim.ted by Bray No.2. Some ch~mjc.1 pmp'''''L'S "f 'he $Oils and """,mem pc"ainint: to Sanborn Field i, t:ivcn in Table I .

Th. pH of the soil, was determined by mixint: 10 ~ of soil wi,h 2(J ml of O.(J 1 M

Cael, sol ution (12). ]""'opic exchange was carried OUt in uupl icate on I 0 ~ of soil by shaking with 20 ml of 0.00' N citric acid solution ront"inins 1" 1 for 2~ hours. Afcci the soil mixture was ,haken in an end-over.end .haker at room temper,,,u n:, the $;Imples centrifug.,.j, 'he dear ,upcrnaten! I iquid was remo.'...!. The ... dioacl;.i ty of 1'." in 'he supc"'alem was determined by liqoid scintillation 'o"minS, with" Sd mixture of Trilon X· ]OO, (oluene, PPO and POPOP. The ratlioani.ity of Ihe samples "nd the control solution was m"",urro with a Packard Model .1(K).1 Tti·Carb Scintilla,ion Counter. The c"nCenttlll;On of the non·radioaCtive phosphorus was dctCtlninL-tl by the iSCorbic .cid m.thod wilh • Beckman DB Sp,.-crruphmomc{cr (I I). 11,. I"hile pool phosphorus (LPp) and the tlis"ibution c{)(:ffici~nr o( phosphoros (Kd) of each soil were calculaled from Ihe valucs obtained by SpI."",ro'l'horomctri, an.lysi, ."d isotopic measurementS (',II).

I.pp _ COncon' .... ti"" ofP in ",Iurion (I>pm)

Ra<iiooe,i"i,y of p" in ..,I",ion

Volumo1>l" ",h"i"" (m!) X 1(10 , Air dry wei!;],t 1>1" ",il. (Sl

Kd _ RO<ii""",ivi,yofpll in ",lid ph:&(tpm) X Volumt of ",Iu,io" (m!)

RO<iioac,ivi,y of p" in ",Iudon «pm) Ai, dry w<i~ht of ..,il (iI)

The exltllC!able phosphorus was delermine.! by Btay No.2 ",agcn(. Two g "f soil with 20 ml of ntay 2 enractan, were shaken for 5 minutes. The amOunt of phosphorus in the ext""l was dele(m;ned by the ascorbic acid method . Phosphorus sorplion and the phosphmus f~rtilizer requiremenl were measured u,ing the method d<"lldoped by Ozan<>e and Shaw (7. 8, 14). Two g of air dry soil were introducro into <"<JUllI weight cemifug~ tubes w;lh 20 ml of O.OIM Cae! solulion containing 0 ro 40 ppm of phosphorus. The ttiplicoted mixrutC"l were ,hake" for 17 hours On the end-ovtr·end shaker and centrifuged for 10 minutes at 2,000 rpm, Afrer the (Oncenrnllion of phosphorus in the superna,ant was determinro, rh~ amoun< of phospho(u, absorbed in the ,upernat~nr was de tumioe<l, Ih. amOunt of phosphor". absorbed by rhe soi] and Langmuir phosphorus maxima we r~ calculared (13).

Research Bullet i" 1062 3

RESU LTS AND DISCUSSIO N

Phosphorus Ihal disappeared from solulion was lSSumed 10 have t>cx,n sorbe<l. These valu .. a~ show" in Figu", 1. The optimum phosphorus coneem ... ,ion in ,he soil solu,ion for good pia", grow,h may vary with plan' sp«ies and the soil moiSlu~ con,.,,1 (I). A concen, ... rion of 0.2 ppm ha. ~n sugge,,<:d as one~, which mOSI plant. will atta;n maximum growth (}).

A value of 0.3 ppm wos used os a standard v.lue fur establi.hing fe«ilize r ... ,e for wheal (13). For Ihis study. Ihe phosphom .... ,us anJ ,he fe«ilizer rrquirrmen' of =h soil wos evalual..d wing 0.3 ppm.., a eri.ieal concen, .. ,ion in Ihe equilibra,..d solution. The soil of pl(KS 17, 9, \3, 19. 38 and ~ from Sanborn Field sorbed 123. II ~ . 82. 5'. 47 and 40 ug PIg soil, resp«tively. Phosphorus should be appl ied .0 .hell: soils fm maximum plam growth.

The other soils sludi..d we", .uffieien<1y phosphorus salUral..d '0 ,h. , P in solution .xcec-ded O. 3 ppm. Th ... would nol rr<luire furrher phosphorus fertilization for growlh of even ,he mOrt demanding crops (3, 7. II). The phospho",. r"<lui~menlS of pion 9, 13 and 17 Wert higher than lhe other soils be<:aUll: Ihese plols had not been previously fertijitcd . Although Ihe P sorption iso,herm melhod h.s foil..d someri", .. to eval",,,. Ihe P supplyi"g capabililie!l of widdy differing soils (I), generally i, agrttd well wi,h plant accumulalion of P (3).

The labile pool i, ddined is t he 'um ofP in Ihe soil solution and the amOunt ofP on ,he soil exchong .. when ,h. soil is e<luilibral..d wilh 0.005 N citric acid solulion. The labile pool w.., d .. ermin..d by isotopic exchange. The av;lilable P wos Ihal amOU nl as ex,race..d by Bray No. 2 solution. The di."ibmion coefficiem and ,he phosphorus ~bsorp'ion maxima are given in Table 2. The eel .. ion,hips w.>rt lOugh' among 'he four factors invelligaled. Consi .. en, "end, w.>rt nOl observed among 'he amounrs of P sorbed and Ihe quamiry found in the labile pools. In mosl ;ns,anc ... ,he lab ile P W;>I

well coltel.I..d w;,h 'he amoun, .. tract..d wilh Bray No.2 (f ig. 2). The magnilude of P adsorption muima decreased with inc~asing percentage of sand in Ihe soils .

n.. intensity (aclor of soil P was inv .. ligated and give" in T.bl~ 3. The dimibu';on coefficient, Kd, may be ~gard.d is • pracrical measu,,, of rhe ,.Ialive bonding of ions 10 ehe soil (I'). The appartnr intonsi,y raccor, Kd(9), will change with tbe amount of P in ,h. labile pool, th~ adsorption properties of ,h~ soil colloid and ,h~ kinds of phosphorus in 'he $Oil. The 0.005 N cilricacid P and the amounl of P found in lhe 0.0 I M Cae 1, wert bolh inCteued when (ertilize, phosphorus W;>I add..d 10 the soil. Wi.h ,he exceplion of Ihe Beulah soil, Ihe phosphorus in 0 .005 N cil,i( acid was closely ,.la,«I to Ihe labile pool P.

The Sanbom field samplC! show..d. P sorption maximum in ,he tango of 249-377 mglkg. The diffeeences can be eel.,ed to tho O.M. depletion. Tabl. 4 show. un' .... t..d plots 9, 13 and 17 to have a P sorplion muimum of 357 mgIkg. The average value fo, Ihe I .... '..d plots was 287 mgfkg . The average O. M.% fOl , .... ted plou was 1.6% OS compar..d to 2.5% for Ih. unl,....I..d plots. The higher than ,xp"',..d P sclp,ion maximllm shown by plOt 19 is possibly. resull o( a change in distribution caused by ,.moving grass hay.

4 Missouri Agricuhural b perirmm Sc,uion

So.nborn Field pIon were ucellem for nalUl.ing .~ dr",,,. of f=ili..,. trn-tmmlS on .~ amounn and kinds or pllosphotu$ remaining in .~ $Oil. TIlt plou are of Itu yalue for comparing $Oil 'ur P 10 crop yield., .iMe ,~ ni,rogon ' .... 'men" Wl:re no. uniform , A rela.ionship W&J obK",td betwten.he j!rain yitld, of wheat and .htl_bile P of plo .. 9, 5, 2 and 10 (F'g, }). TIlt distribu.ion cotlTicien, Kd and .he yield of wheal . 150 ,ho,.".C'd muon_bl. rela.ionship.

SUMMARY

Soil ..... mpled from Sanborn Field, and rhe . lIuyi.1 land associared ... ith .he Miniss ippi aod Missouri Riyers , were .«>died in rel • • ion to lhe ounou", of P tx' rac,td by Bray'. reage",. lhe .ize of Ihe labile pool. .he amounn soluble in 0.005 N citric acid, ,he phosphorus ildsorplion capaci, y OS meiiSured wilh 0,0 1 M GtCl 1 Ind ,he di,,,ibu,ion coefficient, Th. phosphorus ildsorption capaci.y w" d«r«Sed, , .... phosphorus p'u",".ion and Ihe labile pool increased when lime. P ferrili'<Cr.nd mlnure were applied ro .he soil.

This s.udy "'Waled rhe (ollowing ilems of impon.",e: I. 1M $Oil found on plo!. 17, 9, \}, }8 and 5 ""ffC no . .... ura.td wi th phoIphorus,

wh ile . he soil. or plOtS 2, 10, 20. and ,he Satpy. Beul_h and Sha.1<ey K.ies _re ... ,ura.ed.

2. A high Kd (lo ... 'n .cns;,y) for P ..... found on soils 9, l7.nd Minouri Ri~r So.rpy soil. A low Kd was found for 'he Beulah and Shirkey wil,. The low Kd olmfYed On plot to migh' be a re.ul, of manure " .. ,menu.

}. Unltea.ed pion 9, I} I nd 17 ,howe<! I low Ie....l for Ilbile pool phosphoru •. The amou nlS of "'Ira.cl.ble phosphorus were also found 10 be I""". It i. of inrem. ' 0 note d ... , plOt 10 which has been ,rn-,ed ... i,h manure and cropped ro ron,in<>(lU' w ..... has .M hights. labile pool, i. i. higher .han lhe soilsof ,he .;vcn. PIo< }8 which was Irn-.ed ,..i.h an nual.mounl. of manure for n yfton, .hen . ..... Ied .. ;Ih PA in amoun .. eq ual.o 12 lbs annually for 75 yean. reveal. a low levd in 'M labile pool. Thi. in.dicat" .ha, ,~ annual addi.ions of 12 Ibs of PA will 001 inc~

phosphorus level, when .he soi l i. being cropp«!. 4. The amoun. of phosphorus eX"'I"ed ",i,h S .... y. No.2 reagent correl •• ed ",ilh I ....

• iu o( ,he labile pool for an soils ",i ,h ,he u«p.;on of Supy and lkul.h. This obsc:rw.;on supportS t~ s"&8ution .ha. n'f'IC .. ble phO$phoruI .. ill muir in a relilblr yoJ"" fot .he liu of I~ labile pool fur all soils r>«:ep< .hose which contain apa,i,e.

LITERATURE CITED

I. BllIaux,]. S., .nd D. E. Pea,ltt. 1975. ~lacionshil» bc.w«n sorption.OO IIdwrprion of phospho(UI by soil •. S';/ Sri. Sot: . ........ Prot:. 39:2n.

2. Becken , P.H .T., and R. E. W hile. 1964. Srudies on.he phosphate poten.ial! of soils. Jil. ~ pool of b bile otganic phospha.e PI •• I S';/2 1:2'3-282.

Research Bulletin 1062 S

3, &ckwirh , R. S. 1965, $Q.bo-d phospha ••• , "andard supernatam co~n, ration OS ao (,Hima,e of the phosphate n«<ls of soils. AUfl , J. Exp. Agrif. 1I,,;m. HJilb. S;H-~8.

4. Bowman, R. A" S. R, O lsen, and F: S. Watanabe. 1978. G=nhouse "".Iu.,ion of residual ph~ph.,e by four ph~phoru. methods ;n neu,ral and ",I",=u. ",ilo. Soil Sf;, SI>(. Amtr. Prtlf. 42A51_4~4 ,

5. CI •• ke. A. t .. and E, R. Graham. 1965. Zinc diffusion and dimibution coc:fficients in soil as affecttd by ",il ,extu~, zinc concentration and pH. Soil Sci. 105:409-4 II.

6. Dalal, R. C., and E. G. HaUswOrlh. 1976. Ev:aluaeion of ,he param .. e", of soil pho$pho.u. availability factor. in prtdiCling yield response.nd ph(lSphoru. uptake. S~i1 Sd. SI>(, 11m .... Prtlf. 40:54 1-546.

7. Fox, R. I.. 19SI , EXIOrnal phosphorus <"«Iuiremen,s of crops. In R . H. Dowdy, ). A. Ryan, V. V. Vol k, and D. E. Baker. (Eds.) ChemiSI? nf the 'Soil Env;",""""1 Chap,. 12. pp. 223-239. Madison WI: A.S.A.

S. Fox, R. L, 1979. Comparative respon5e$ of fidd Iw,wn crops to phosphate concentrations in soil SOlutions, In H. Mundi and R, Staples (Eds.) SIms

Pb)Jiol.lJ' in Crop PI"nt,. New York: John Wilt')' and Son£, 9. Fox, R. 1.., D. L. Plucknetl, and A, S. Whiu><,y. 1968. Phosphare <"«Iuireme",!

of Hawai ian lar050ls and ~.iduaj dTecn of fe.ti jiu:r phosphorus. I"" C.,,/!.. Soil Sri. 1"r""f.2:301-31O.

10. Fox. R. L. , aod E. J. Kamprath. 1970. Phosphate sorption iSO(hw"IU for eval uating the phosphate <"«Iuiremen .. of $Oils. Soil Sd. Soc. Amtr. Prtlf. 37:70-74.

11. Graham, E. R. 1973. Selective Distribution and Labile Poolo of Micro-nutrient. as Facto" Affecting Plam Update. Soil Sri. S«. 37:70-74.

12 , Lee, Y. S., and R . J. (la.eler< , 1977. Amssing phosphorus ferriJi> •• necd.1xosed on i"tensity _ capacity relationship', Soil Sci. SI>(. II mtr. PrIIf. 4 I :710-7 12.

13. Lopez, P. L., and E. R. Graham. 1972. Labile pool and plan' uptake of micronutriems: l. Determination of labile pool of Mn, Fe, Zn, Co. and Cu, in deficien, ooils by i50topic exchange. S.i! Sri. 114:29~-299.

14. NCR $oil Te"ing Comm;uce. 19n. RtwII~nrltt1 ebtmir,,1 S.il Tut Promilml for I'" Nortb Cmlr,,1 Rtgion, Fargo, NO: Nor. Oak. Agric. E. pt. Sill. 6ull. 499:I-H.

n. Oloen. S. R., and F. S. WOIanabe. 1951. A method to d .. ermine a phosphorus ad50.ption maximum of soils OS m .. sured by ,be Langmuir iSOlhe.m. Soil Sci. So<. A~r. Prtlf. 2Lt44-149.

16. Ounne, P. G ., and T. C. Shaw. 1968. Ad". ntages of (he recently developed phosphate sorption test Over the older extractant method. (or soil phosphale . Inl .

eM/(. S.il Sci. Tr"lIJ. 2:273-2g0. 17. Prout, W. E. 1955. Ad50rpdon of radioactive wastes by ,""annah rivcr plant soil.

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Reseuch Bullelin 1062 7

Table 2. labite pools, distribution coefficients and adsorption of phosphorus,

Soils Brays No. 2 LP P % p max.

Sonbom F i~l d ppm P ppm Kd OM "", , " 66 '" '.0 '" , " .. '" U '" , " '" '" "

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T.ble 3. Distribution coefficientS con~"'rltion of phosphorus in various extracts .

0. 005 N RadioactivilY Ci tric Acid O.OI MCaCI , of P remaining

Soils Kd P P in solution

Sanborn Field ppm ppm • , '" .367 .102 1.11 , '" .183 .0)6 " , '" .066 ,011 " " '" .787 ,281 1.30

" '" .066 .021 1.11

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• •• g , Table 4. Labile pools. sorpcion max. ph05phoru5 saturuion soluble phosphorus and t~at~nl$ of soii. > • ,.

0 PlOt Fertilizer Approximate P Labile .01 M ~ Plot/Soil History P .dded over Sorption P P CaC ll

Dtsignat ion (S ummary) the years M~ Pool Saturation P pH it " Kolb' -. m"'" • No"- " ~

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Research Bulletin 1062 9

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Figura 1. Phospnata adsorption. wi1h various equilibrium conoentratkJrl 01 P, by some MISSOo.IfI soils.

10,0

10 MislI()Uci Agcicul'ural Ex~rimC'n. S ••• ioo

Research Bulletin 1062 11

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