MIECZYSŁAW BIRECKI, JÓZEF GASTOŁ
IN FLU EN C E OF PL A N T S AND SO IL FR EEZIN G
ON THE FR A CTIO N A L HUM US CO M POSITION OF THE SOIL AND SO IL A G GREGA TES
Departm ent of General Soil and P lant Cultivation A gricultural University, Warsaw
T he a g ric u ltu ra l an d soil science lite ra tu re [5, 8, 9, 11] gives an e x h a u stiv e c h a ra c te ristic of th e organic substances in v ariou s ty p es of soil. H ow ever, th e n u m b er of w orks [1, 2, 3, 7] devoted to th e in flu en ce of p la n ts and v ario u s o th e r e x te rio r fac to rs on th e q u a n tita tiv e and q u a lita tiv e com position of h u m u s w ith in one ty p e of soil is v e ry lim ited. C onsidering th is p ro blem r a th e r im p o rta n t, w e devoted tim e to its study, and th e re su lts a re re p o rte d in th e p re s e n t paper.
Soil sam ples w ere collected from th e arab le lay e r in th e a u tu m n of 1960 and 1961 fro m p'lots of a m u ltia n n u a l ro ta tio n a l ex p e rim e n t, laid o u t on m ed ium black soil o v erlyin g m ed ium bo u ld er loam on th e E x p e ri m e n ta l F ield of th e D e p a rtm e n t of G en eral Soil and P la n t C u ltiv atio n in C hylice, G rodzisk M azow iecki County, W arsaw A g ric u ltu ra l U niversity. Soil sam ples collected from th e follow ing plots w e re com pared as reg a rd s q u a lita tiv e and q u a n tita tiv e h um u s com position:
— from u n d e r a potato cu ltu re, — from fallow ,
— fro m u n d e r an a lfalfa-g rass m ix tu re in th e 5th and 6th y e a r of its use.
The ex p e rim e n ts w e re c a rrie d o u t in 4 replication s. T he su rface of th e e x p e rim e n tal plots w as 15 sq.m.
The g en eral ch a ra c te ristic of th e 0— 20 cm. soil lay e r in th e above m en tio n ed conditions is given in Tab. 1.
Soil sam ples w ere ta k e n from each p lot as a pooled sam ple con sistin g of five single ones collected ra n d o m ly one each p lot into po ly e th y le n e bags. The sam ples w ere b ro u g h t to th e sam e m o istu re content,
60 M. Birecki, J. Gastoł
and th e bags w ere k e p t tig h tly closed d u rin g th e w hole p erio d of th e la b o ra to ry e x p e rim e n t. T he sam ples from each p lo t w ere tre a te d in th re e w ays:
I. control sam ples n o t su b je c ted to freezing,
II. frozen o n ly once a n d k e p t a t — 10°C. for 42 days,
III. frozen and su b je c ted to th aw in g sev eral tim es in course of 42 days.
T a b l e 1 General c h a r a c te r is tic of black medium s o i l in the 0-20 cm. la y er of the p lo ts studied
S o il samples Total С Total N pH in KC1 Hydro l y t i c acidify Sum o f bases a fte r Kappen Content (a fter EgnerJ in 100 g. of s o i l of a v a ila b le percentage o f s o i l fr a c tio n m e /100 g . of s o i l p205 K20 1-0 .1 Q.I-О.02 < 0 . 0 2 % mg. mm.
From under p otatoes 1.12 0.11 7 .0 0.49 23.95 9.4 6 .8 5 0 .0 20.0 30.0
From fa llo w 1.14 0 .11 7 .1 0.46- 23.95 10.8 6 .7 5 0 .0 21.0 29.0
From under a lf a lfa -g r a s s
mixture 1.53 0.16 7 .2 0.43 24.50 13.7 6 .0 5 0.0 21.0 2 9.0
In o rd e r to estab lish th e changes occuring in th e soil fro m u n d e r th e cu ltu res in v estig a ted in dependence on freezing, th e follow ing d e te rm i n atio n w ere m ade:
— to ta l carbon b y T iu rin ’s m ethod,
— to ta l n itro g e n co n te n t b y T iu rin ’s m ethod,
— fra c tio n a l h u m u s com position by T iu rin ’s m ethod in th e m odifi cation of P o n o m a r i e w a [10],
— fractio n al h um us com position by th e m eth o d of K o n o n o w a a nd B i e l c z i k o w a [6].
T otal carbon and th a t of th e p a rtic u la r hu m u s fractions w as d e te rm i ned by T iu rin ’s m eth o d w ith th e use of p h e n y la n th ra n ilic acid as in d i cator.
E a rlier in v estigations of th e p re se n t [2] as w ell as of a n u m b er of o th e r a u th o rs [1, 7] d e m o n stra ted th e u sefuln ess of T iu rin ’s m etho d fo r d ete rm in in g th e h um us fractio n s w ith in one ty p e of soil, in d ependence on its sta te of cu ltiv atio n and ex p loitation , and on th e grow ing p lan ts. T he q u estio n arises w h e th e r th e sim plified quick m eth o d developed by K o n o n o w a a nd B i e l c z i k o w a [6] m ay also be success fu lly applied for d eterm in in g th e h u m u s com position in such conditions, and w h e th e r th e re su lts o b tain ed by th is m eth o d are co m parable w ith those o b tain ed b y T iu rin ’s m etho d . Som e a u th o rs [4, 12] claim th a t b o th th e se m etho ds are of little use as fa r as soils w ith in one ty p e a re concerned.
E ffect of Vegetation and freezing on hum ic and soil aggregates 61
T he fra c tio n a l com position of h u m u s d e te rm in e d b y T iu rin ’s m eth o d in P o n o m ariew a’s m odification in black m ed ium h e av y soils u n d e r th e c u ltu re s exam ined, in d ep endence on freezing is show n in Tab. 2 (m eans fo r th e sum m ers of 1960 and 1961).
T hese d a ta d em o n stra te th e d istin ct d iffe re n tia tio n in th e hum us fractio n s in th e in v estig a ted soil depending on th e p lan ts and tre a tm e n t. T h e n o n -fro zen control sam ples fro m u n d e r alfa lfa -g ra ss m ix tu re w ere found to contain m ore h u m u s w ith stabilized s tru c tu re containing m o re h u m ic acids fraction s, n o n h y d ro ly zin g fractions — h um ins an d ulm ins — a n d less fulvoacids and su b stan ce hy d ro ly zin g in 1,0 N H 2S 0 4. E vidence of th is is also fo u n d in th e calcu lated h u m u s indexes, i.e. th e ratio of ca rb o n of th e hum ic acids fractio n s to th e carbon of fulvoacids, an d th e ra tio of th e carbo n of h u m in and u lm in fractio n s to th e carbon of th e fu lvoacids fractions. These in dex es prove th a t th e hum ic com pounds in th e soil u n d e r th e a lfa lfa -g ra ss m ix tu re are b e tte r stabilized th a n in th e fallo w soil and u n d e r th e potato c u ltu re. The in dexes of th e fallow soil w e re also h ig h er th a n those of th e p o tato c u ltu re. D ifferences w ere also fo u n d in th e binding a b ility of p a rtic u la r fractio n s of hum ic and fulvo acids w ith th e m in e ral soil p a rt. U nd er th e alfa lfa grass m ix tu re a g re a te r accu m u latio n of hu m ic acids fractio n s sta b ly bound w ith th e m in e ral p a r t of th e soil w as found, w h ereas u n d e r th e potato p la n ts th e rev e rse w as observed. W hen th e soil sam ples w ere frozen, changes o ccured in th e q u a lity of th e organic su b stan ce in th e soil. In sam ples fro zen once, a stab ilizatio n of hu m u s w as observed: th e q u a n tity of h um ins and ulm ins a n d th e a m o u n t of hum ic acids increased , w h ereas th e a m o u n t of fu lv o
acids and of th e com pounds h y d ro ly zing in 1.0 N N 2S 0 4 dim inished. E v id e n tly continuous deep freezin g produces a re o rie n ta tio n of th e soil an d m akes possible th e stab ilizatio n of hum ic acids. T his ex p la n a tio n fin d s co n firm atio n in th e observed decrease of m o b ility of th e fulvoacids fractio n s (fractions I an d II), an d rise of th e a m o u n t of fulvoacids sta b ly bou n d w ith th e m in e ra l p a rt of th e soil by m eans of th e silica R 20 3 form s (fractio n IV). C e rta in changes also occur in th e course of freezing in th e size of th e hum ic acids fractio n s: th e q u a n tity of fra c tio n II of hum ic acids bound w ith calcium as w ell as th e fre e h um ic acids in creases — p ro b ab ly in connection w ith th e fall of th e fre e fulvoacids content. The h u m u s in dexes calculated p oin t to a stabilizing effect of continuous deep freezin g applied once to th e soil h um us. R epeated freezing an d defreezing, on th e o th e r hand, increases th e m o b ility of th e hum ic and p a rtic u la rly of th e fulv oacid s’ fractio n , as tra s tic a lly show n by th e h u m u s indexes calculated, and p a rtic u la rly by th e H : F ratio . S im ilar re su lts of th e fra c tio n a l hu m u s com position of m ediu m black soil w ere o b tain ed by th e m eth od of K ononow a an d Bielczikow a (Tab. 3). The d ata in th is tab le
T a b l e 2 F ractional composition of humus of me.dium black s o i l from the p lo ts studied in dependence on freezin g
(as percentage of t o t a l C, in the 0-20 cm. layer; by the method of Tiurin in ponomariewa*a m odification (means for i 960 and I96I)
ob w Humic a c id s f r a c t io n s С F u lv o a cid s f r a c t io n s С 05а 01а о 0 о •но м 3 to 0 rH T) ^ о* $ = •H •H О S o i l sam ples È $ 3 0 3 © OH rO-r* л 3 ? XI-•-> CM о <D Л.гНÜ Ф0 1—) f i P ГО Лч-> СМ о Ü S &•н «-и N TJSа X50Mi 0 xj 0i.* s «M а 0 >—ł 0 s J-t'o 0 a tc ■rH и0 a 0 № J >*о »ö ä W ООО о «M 1—1 0 <—1 0 1 T i Ö xJ <—ł H <D 'ta а та <—) Н о . h O ‘H OM О =J -*-> +) 1 I 3 3 •P § в § ^СЯ О Ч* I I I ■P ’Нг^ • • ■«-» Eh *0 Éh *o m M S B rQ 0 ДЭ w •P ОшД О да со -Р ОД-Н « From under p o ta to e s 1119 111 , 10.08 3 .4 7 .7 9 .9 7 .9 2 5 .5 4 .9 7 .8 9 .3 9 .3 3 1 .3 7 .2 3 2 .6 0 .7 8 1 .0 4 From f a ll o w 1144 113 10.12 2 .8 7 .4 1 0 .7 7 . 8 2 5 .9 3 .6 6 .8 8 .4 9 .8 2 8 .6 7 .7 3 5 .0 0 .9 1 1 .2 2 From under a l f a l f a - g r a ss m ixture 1530 156 9 .8 0 2 .2 5 .6 1 7 .7 6 .2 29-5 2 .9 4 .0 6 .6 1 2 .6 2 6 . 1 4 .9 3 7 .3 1 .1 3 1 .4 3 I not fr o z e n 1263 126 10.02 3 .1 5 .5 1 3 .6 7 .9 2 7 .0 3 .5 6 .0 8 .8 1 0 .5 2 8 .8 6 .9 3 4 .2 0 .9 4 1 .1 9 I I fr o z e n once 1262 127 9 . 9З 2 .1 6 .8 1 4 .7 . 6 .6 2 8 .1 3 .1 4 .2 7 .0 1 3 .1 2 7 .4 5 .6 3 6 .8 1 .0 2 1 .3 4 I I I r e p e s te d ly fr o z en and thawed 1263 127 9 .9 4 3 .0 8 .2 1 0 .4 7 .2 2 5 .8 4 .6 8 .4 7 .8 9 .0 2 9 .8 7 .2 3 4 .2 0 .8 6 1 .1 5 C onfidence i n t e r v a ls P .- 0.95 a / f o r the c u ltu r e 28 14 0 .1 5 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 0 .0 7 0 .1 5 b / fo r the treatm en ts 128) • (14) (0 .1 5 ) 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 0 .0 7 0 .1 5 с / f o r in t e r a c t io n s (35) (16) (0 .3 0 ) 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .0 8 0 .1 4 * Not s ig n ific a n t !. B ir e c k i, J. G a st o ł
T a b l e 3 Fractional composition o f humus in medium black s o i l from the p lo ts studied in dependence on freezin g
(аб percentage of to ta l С in the 0-20 cm. layer) by the method of Kononowa and Bielczikowa
S o il samples and treatment T o ta l С m e ./ 10 0 g . of s o il T o ta l N m g ./ 10 0 g . of s o il »о С e x tr a c te d w it h a m ix tu re o f 0. 1 M N a4 P20 ? an d 0. 1 N N aO H H um ic a cid s С о u 0 (О1 о ► »-H Сч No n -h y d r o ly z in g co m p ou n d s С л 'т ТЭ о а> со ■** СМо cd и -»-> a и ® Г-Н о о Fre e h u m ic ac ids С С of hu m ic a c id s bo un d w it h C a an d U g R a ti o of h u m ic a cid e С to fu lv o a cid s С H :F 0 ш о •н а 1 s Л О « «м о Ô “5 чН «И 4> Я 2 м VO VO чО . W Ь - iS * S
From under p otatoes 1119 111 10.08 45.4 19.9 25.7 54.6 4 .9 7.7 12.0 0.78 2.14 3.0 6
From fallow 1144 113 10.12 4 4 .2 19.7 24.5 55.8 3 .6 7.4 12.3 0.83 2.32 3 .0 0 From under a lf a lf a - grass mixture 1530 156 9 ^ 0 4 0 .6 21.9 18.7 59.4 2 .9 5 .6 16.3 1.17 3.13 2.92 I not frozen 1263 126 10.02 43.4 20.2 23.2 56.6 3.5 5 .5 14.7 0.90 2.51 3.00 II frozen once 1262 127 9.93 42.3 21.6 20.7 57.7 3 .1 6.5 14.8 1.01 2.73 2.96
III repeatedly frozen and thawed
Confidence in te r v a ls P -1263
■ 0.95
127 9-94 44 .0 20.3 23.7 5 6 .0 4 .6 8 .2 12.2 0.88 2.39 3.02
a / for the culture 28 14 0.15 0 .9 0 .9 0 .9 0 .9 0 .9 0.9 0.9 0.10 0.21 0.12
b / for the treatments (26) • (14) * (0 .1 5 ) 0.9 0 .9 0 .9 , 0.9 0.9 0 .9 0.9 0.10 0.21 (0.12)
с / fo r in te ra ctio n s (35) (16) (0 .3 0 ) 1 .0 1 .0 1 .0 1 .0 1 .0 1.0 1 .0 0.09 ' 0.19 (0.13)
* Not sig n ific a n t
E ffect of ve ge ta tio n an d fr eezing on h u m ic an d so il a g g r e g a te s
64 M. Birecki, J. Gastoł
in d icate a d istin ct d iffe re n tia tio n in th e h u m u s fractions, both as re g a rd s th e c u ltu re s in v e stig a ted an d th e tre a tm e n ts to w hich th e soil w as su b jected . This is also illu s tra te d b y th e h u m u s indexes. If th e re su lts o b tain ed by th is m eth o d are com pared w ith those obtained b y T iu rin ’s m eth o d it ap pears th a t, a lth o u g h t th e sizes of th e fractio n s e x tra c te d in th e case of b o th th ese m eth o d s w ere d ifferen t, T iu rin ’s m eth o d yielded a m ax im u m am o u n t of soluble h u m u s com pounds. N ev erth eless th e tre n d s of changes and d iffe re n tia tio n in th e fraction s a re in a g re e m e n t in th e case of both m ethods. Evidence of th is m ay be fo u n d in th e h um u s in d ex es calculated: th e H : F ra tio has closely sim ilar values in both cases, and th e ratio of h u m in to fulvoacids follow s th e sam e tre n d in both m ethods, th o u g h its v a lu e is tw o tim es h ig h er for th e soi’1 sam ples in v esti gated by th e m eth o d of K ononow a and B ielczikow a. It m ay be concluded th e re fro m th a t a single tre a tm e n t of th e soil w ith 0.1 M N a4P 20 7 -r + 0.1 N NaO H a t pH 13 is no t su fficien t for th e m ax im u m e x tra c tio n of all th e soluble hum ic com pounds. L ite ra tu re d ata confirm th is view [12]. N everth eless, for black m ed iu m soils, th e tre n d of changes and d iffe re n tia tio n of th e hu m u s fractio n s o b tain ed b y bo th m ethods shows sim ilar reg u la ritie s. T h erefo re b o th m ethods, and p a rtic u la rly th e quick m eth o d of K ononow a an d Bielczikow a, are u seful for d ete rm in in g th e p la n t in flu en ce upon th e q u a n tity a n d q u a lity of h u m u s fractio n s w ith in one soils ty p e. T he o ptical d e n sity of hum ic acids d e te rm in e d E 4 : E 6 w hich in some e x te n t reflec ts th e condesation of hum ic acids m olecules, w as a c tu a lly found to be th e h ig h est in th e soil from u n d e r alfalfa-g rass m ix tu re s in accordance w ith th e q u a n tity of hum ic acids in th e soils fro m u n d e r th e given p lan ts. The change in colloid-chiefly hum ic acids- d ispersion in th e soil u n d e r th e in flu en ce of fro st is only w eak ly re fle c te d in th e optical d en sity of th ese acids. The v alues of th e E4 : E 6 ratio are sim ilar u n d e r all tre a tm e n ts . A sim ilar phenom enon is observed in th e q u a lity of th e hu m u s of th e m ech an ically -stab le agg reg ates of th e 3— 1 m m . fra c tio n from th e plots studied.
T he d ata in Tab. 4 o b tain ed b y T iu rin ’s m eth o d in d icate a d if fe re n tia tio n in th e hu m u s fractio n s of m ech an ically -stab el aggregates o f 3— 1 m m . size in dependence o n th e grow ing p lan ts and th e freezing tre a tm e n t. The to ta l co n ten ts of h u m in and hum ic acids fractio n s are sig n ifican tly h ig h er u n d e r a lfa lfa -g ra ss m ix tu re s th a n u n d e r potatoes. A d istin ct stabilizatio n of th e hu m u s is also observed, w h e n m echanically- sta b le aggregates a re su b jected to freezing ju st once, w h ereas re p e a te d freezing an d th aw in g increases th e m o bility of th e hum us. It is in te re stin g th a t in m ech an ically -stab le ag g regates of th e 3— 1 m m . fra c tio n u n d e r a lfa lfa -g ra ss m ix tu re th e re is m ore hum ins an d ulm ins th a n in th e b u lk of
R o c z n ik i G le b o z n a w c z e
F ractional composition of humus in m echanically-stable aggregates of the 3-1 mm. fr a c tio n (medium black s o i l under the cu ltu res studied) in dependence on freezin g (as percentage of t o ta l С in the 0-20 cm. la y er) by T iu rin ’ s method in the. m odification of Ponomariewa
T a b l e 4
ьЬ ад Humic acids fr a c tio n s С Fulvoacids fr a c tio n s С Wа соа о
о о • г* ьп 3 W о S o il samples and treatment 5 сш 0 И à æ о -ö i . O rH ДЭ -г* л XI о4J СМгл • s « HZ) 9 0> О i—( ДЭ -гН л S j F * ^ х: о 4 * О о СВ со Vi W) СМ •н ы отэ >> а н м ш 1 Л о и •Н СО 1 2 Л о а О <~4 * d о а Vi о ► Vi О 5 5 5 VI Л и о о о >
н о i—( о 1 о В 'ta с; тз г-н i—i со о а пЗ Ö тз i Н °гН >»о-н ОМ о з
о ■р 0) -*-> Ó § ®
13
Vi 0) -»J ° g аз13
-♦J ОТЗ о о 1 1 +> -нн £ *4 fH о 6-» о *н РИ £ ® И СО л о ,-Q (0 -2 « о Pd в ч о Р5 +»From under p otatoes 1009 120 8 .4 0 4 .0 7 .2 10.9 7.5 25.6 4 .3 9 .3 8 .7 9 .6 31.9 5 .4 3 2 .1 0.80 1.04
From fallow 1102 118 9.33 3 .8 5.5 12.3 7.6 25.4 3 .0 .8.7 8 .8 9.3 29.8 5 .5 35.5 0.85 1.19
From under a l f a lf a -
grass mixture 1537 160 9.60 2 .8 4 .4 18.4 5 .9 28.7 2.4 4 .4 7 .6 11.3 25.7 3 .9 38.9 1.12 1.51
I not frozen 1215 133 9.13 3 .3 5 .1 14.4 7.1 26.6 з . з 7.7 8 .7 9 .6 29.3 5 .5 3 5.2 0.91 1.20
II frozen once 1217 134 9.08 3 .4 6 .8 14.6 6.7 27.6 2.7 6.5 7.3 11.3 27.8 4 .2 37.1 0 .99 1.33
III repeatedly frozen
and thawed 1215 131 9.27 3 .8 5.6 12.6 7 .0 25.2 3 .8 8 .2 9.0 9.2 3 0.2 5 .1 35.7 0.83 1.18
Confidence in te rv a le P -- 0.95
a / fo r the cu ltures 26 10 0.24 0 .9 0.9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0.07 0.12
Ъ/ for the treatments (26) • (10)* (0.24) 0 .9 0.9 0.9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0 .9 0.9 0.07 0.12
с / for in te ra ctio n s (31) (9)* (0 .4 5 ) 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1 .0 1.0 1.0 1.0 0.08 0.14 * Not s ig n ific a n t CT> СЛ Eff ec t of veget ation an d fr eezing on h u m ic an d so il a g g r e g a te s
а»
0 5
T a b l e 5
F ractional composition of humus in m ech an ically-stab le aggregates of the 3-1 mm. fr a c tio n (medium black s o i l from the p lo ts studied) in dependence on freezin g (as percentage of to ta l С in the 0-20 cm. layer) by the method of Kononowa and Bielchikowa
S o il samples and treatment T o ta l С m g . /10 0 g . of s o il T o ta l N m g . /100 g . of s o il ss о r^-o Q> C\J tCj U (X, О z) ^ a 'Ö * 1 Я Й « X я "Ч S3 о а га <0 г—1 СО г—1 . -*-> • о К -С о О) -ł-> Tl •н <Н Ö О № О (О Hum ic ac id s С F u lv o a ci d s С N o n -h y d r o ly z in g co m p ou n d s С л+> * * «тэ О <и СО -•-> CNJ О Я СО ч-> а X 0) 1—1 о ö Fre e h u m ic a cid s С С of hu m ic a c id s bo un d w it h C a an d M g R a ti o of h u m ic acids С to fu lv o a cid s С H :F R a ti o of h u m in s С to fu lv o a c id s С vO w
From under potatoes 1009 120 8 . 4 0 4 3 . 1 1 7 .9 2 5 .2 5 6 .9 4 . 3 7 . 2 1 0 .7 0 .7 1 2 .2 7 3 .2 0
From fallow 1102 118 9 .3 3 4 1 . 9 1 8 .6 2 3 .3 5 8 . 1 3 . 0 5 .5 1 3 .1 0 .8 0 2 .5 0 3 .0 9 ! From under a l f a lf a -1537 160 9 . 6 0 3 8 .4 2 0 .6 1 7 .8 6 1 .6 2 .4 4 . 4 1 6 .2 1 .1 4 3 . 4 2 3 . 0 0 * grass f ix tu r e I not frozen 1215 133 9 .1 3 4 1 . 6 1 8 .7 2 2 .9 5 8 .4 3 . 3 5 . 1 1 2 .6 0 .8 6 2 .6 6 3 .1 2 II frozen once 1217 134 9 .0 8 4 0 . 0 1 9 .5 2 0 .5 бо.о 2 .7 6 .8 1 2 .7 0 .9 9 3 .0 4 3 .0 5
III rep eatly frozen
and thawed 1215 131 9 .2 7 4 1 .7 1 8 .4 2 3 .3 5 8 .3 3 . 8 5 . 6 1 2 .8 0 .8 4 2 .5 7 3 . 1 1
Confidence in te rv a l P - a / for the cu ltures
0 .9 5
26 10 0 .2 4 0 . 7 0 .7 0 . 7 0 .7 0 . 7 0 . 7 0 . 7 0 .1 0 0 .2 6 0 .1 8
b / for the treatments ( 2 6 ) * t—• о * ( 0 . 2 4 ) 0 , 7 0 .7 0 .7 0 .7 0 .7 0 .7 0 . 7 0 .1 0 0 .2 6 ( 0 . 1 8 )
с / for in te ra ctio n s (3 1 ) (9 ) ( 0 . 4 5 ) 0 . 6 0 .6 0 . 6 0 . 6 0 . 6 0 . 6 0 . 6 0 .0 8 0 .2 8 ( 0 . 1 6 )
* Hot sig n ific a n t
B ir e c k i, J. G a st o ł
сл «
fr a c tio n a l composition of humus in w ater-stab le aggregates of 3 -1 шт. siz e
(obtained by shaking in water o f 100 g o f m echanically stab le aggregates of the 3-1 mm. fra c tio n )
from the p lo ts studied, in dependence on freezin g (as percentage of t o ta l C) by T iu rin ’ s method in the m odification of Ponomariewa T a b l e 6 S o il samples and treatments T o ta l С m g ./ 10 0 g . of s o il T o ta l N m g ./ 10 0 g . of s o il оеч 0 <D a •H 1 -4-» pq Hum ic a c id s fr a c ti o n s С F u lv o a c id s fr a c ti o n s С С of the fr a c ti o n s h y d r o li z in g in 1. 0 N H 2S 0 4 N o n d y d r o ly z in g co m p ou n d s С (h u m in s a n d u lm in s) R a ti o of h u m ic acids С to fu lv o acids С R a tio of hum ines С to fu lv o a c id s С
^ From under potatoes 980 112 8 .75 5 .2 25.3 30.3 5 .8 3 3.4 0.83 1.10
From fallow 1024 107 9-57 3 .8 25.2 31.2 4 .9 3 4.9 0.81 1.12
From under a lfa lfa -g r a s s
mixture 1500 157 9.55 2 .6 29.6 25.7 3 .2 38.9 1.15 1 .51
I not frozen 1166 124 9.40 4 .0 26.9 29.3 4 .3 35.5 0.92 1.21
j II frozen once 1171 126 9.29 3 .7 28.1 27.9 3 .6 36.7 1.01 1.32
I III repeatedly frozen and
j thawed 1167 126 9.26 4 .0 25.1 3 0.0 5 .8 3 5.1 0 .8 4 1.17 Confidence in te r v a ls P - 0.95 a / fo r the culture, 34 20 0 .30 1 .1 1 .1 1 .1 1 .1 1 .1 0.08 0.10 b / fo r the treatments (34)* (20) (0 .3 0 ) 1 .1 1 .1 1 .1 1 .1 1 .1 0.08 0.10 с / fo r in te ra ctio n s И 0) (26) (0 .4 8 ) 1 .0 1.0 1.0 1.0 1 .0 0.08 0.10 * Hot s ig n ific a n c e ^ CT> -a Ef fec t of ve ge ta tio n an d fr eez ing on h u m ic an d so il a g g r e g a te s
6 8 M. Birecki, J. Gastoł
th e soil (this giving an in d icatio n as to th e relatio n sh ip b e tw e en h u m in s an d fulvoacids). This fac t points to th e ag gregating role of hum us.
A nalogous d ata w ere o b tain ed by th e m eth o d of K ononow a and B iel- czikowa (Tab. 5). In an e a rlie r w ork [3] w e d em o n strated th e h ig h er q u a lity of th e hum us form th e w a te r-sta b le aggregates of th e 3— 1 m m . fra c tio n (obtained by shakin g 100 g. of m ech an ically -stab le aggreg ates of th e 3— 1 m m . fra c tio n in w ater) from u n d e r a lfa lfa -g ra ss m ix tu re th a n from u n d e r potatoes.
The d ata of Tab. 6, p a rtic u la rly th e h u m u s indexes calculated confirm th e s ta te m e n t advanced above, a n d in dicate th a t hum ins, ulm ins and hum ic acids are th e binding ag en t in th e w a te r-sta b le aggregates, since, sim ila rly as in th e m ech an ically -stab le aggregates, th e y are p re s e n t in la rg e r q u a n titie s h e re th a n in th e bu lk of th e soil u n d e r th e cu ltu res studied. Also e x te rio r factors such as frost, influ en ce sig nificantly th e sta b ility of hu m u s in th e w a te r stab le aggregates. T he re su lts o b tained fo r th e h u m u s fra c tio n in th e w a te r-sta b le aggreg ates show a d if fe re n tia tio n analogous to th a t in th e soil and th e m ec h an ically -stab le ag gregates. T he som e is ev id en t from th e h u m us index es calculated.
Sum m ing up th e above disccused re su lts of fra c tio n a tin g analysis of th e hum u s in soil and soil ag g regates of m edium h eavy black soil, it m ay be s ta te d th a t both m ethods, th a t of T iu rin and th a t of K ononow a and Bielczikow a, rev e a le d a sim ilar re g u la rity in th e d iffe re n tia tio n and changes in th e h u m u s fractio n s caused by th e p la n t species an d fre e zing, w ith in one soil ty p e. The to ta l co n ten t of h u m in and hum ic acids fractio ns and th e h um u s index es calculated in d icate th a t, in th e soil as w ell as in m ech an ically and w a te r-sta b le aggreg ates u n d e r alfalfa-g rass m ix tu re , th e re is m o re h u m u s w ith a stabilized s tru c tu re th a n u n d e r a potato c u ltu re. It is c h a ra c te ristic th a t th e h um u s of th e m ech anically an d w a te r-sta b le ag greg ates u n d e r th e given cu ltu res is m ore stabilized th a n in th e b u lk of th e soil. A single tre a tm e n t by freezing stabilizes th e hu m us in th e soil and aggregates, w h ereas re p e a te d freezing and th aw in g causes dispersio n of th e hu m u s an d increases its m obility. The hu m u s in d ex es calcu lated su p p ly th e b e st ch a ra c te ristic of th e changes in th e fractio n al com position of th e h u m us caused by p la n t species and freezin g tre a tm e n t.
REFERENCES
[1] B a r a n o w s k a j a A. W.: Changes in humus com position of sodden-podso- lized sandy loam soil in the annual cycle. Poczw owiedien., 2, 1961.
[2] B i r e c k i M., G a s t o ł J.: The characteristic of some elem ents of soil aggregates from under different cultivated plants. Part. 3. Roczn. Nauk Roln., 84—4—4, 1962.
E ffect of Vegetation and freezing on humic and soil aggregates 69
[3] B o r a t y ń s k i K., W i l k K.: Humus compounds and hum us content in light soils different fertility state. Zeszyty Problem ow e Postępów Nauk Roln., z. 21, I960..
[4] B o r a t y ń s k i K,., W i l k K.: Studies on humus. Roczn. Gleboznawcze, t. XI, 1962.
[5] K o n o n o w a M. M.: The problem of soil humus. PWRiL, Warszawa 1955. [6] К o n o n o w а М. М., B i e l c z i k o w a M. P.: Quick m ethods of de term ination of the hum us com position in m ineral soils. Poczwowiedien., 10, 1961.
[7] К o r o t k o w A. A.: Influence of plants on the humus com position in sodden-podsolized soils. Poczw owiedien., 8, 1957.
[8] M u s i e r o w i c z A.: The hum us of soils. Postępy Nauk Roln., 2, 44, 1957. [9] M u s i e r o w i c z A., B r o g o w s k i Z., S k o r u p s k a T.: M aterials to
the know ledge of the organic compounds in Polisch soils. Roczn. Glebozn., t. IX, 1960. z. 1.
[10] P o n o m a r i e w a W. W.: On the m ethods of changing the humus compo sition according to T iurin’s scheme. Poczw ow iedien., 8, 1957.
[11] T i u r i n J. W., K o n o n o w a м;. M.: Biology of humus and problems of soil fertility. Poczw owiedien, 3, 1963.
[12] W i l k K.: Comparison of a Polish and USSR m ethod for determ ination of hum us com position in soil w ith different stables of cultivation. Roczn. Glebozn., dodatek do t. X III.
M . B I R E C K I , J . G A S T O Ł
EINFLUSS DER KULTURPFLANZEN UND DER EINFRIERUNG AUF DIE ZUSAMMENSETZUNG DER HUMUSFRAKTIONEN
IM BODEN UND BODENAGGREGATET
L e h r s t u h l f ü r A l l g e m e i n e n A c k e r - u n d P f l a n z e n b a u d e r L a n d w i r t s c h a f t l i c h e n U n i w e r s i t ä t in W a r s z a w a
Z u s a m m e n f a s s u n g
Im Herbst 1960 und 1961 wurden Proben der Bodenkrum m e in Rahmen eines Feldversuches m ittlerem dunkjem hum osem Boden, sum pfiger Herkunft, in der V ersuchsstation Chylice bei Warszawa, entnom men. D ie Bodenproben aus Parzellen m it K artoffeln, Brache und Luzernegrasgem enge wurden im Laboratorium nächst folgend behandelt:
I. Ausgangsproben ohne Einfrierung.
II. Einm alig bei der Temperatur — 10 °C während 42 Tagen eingefrorene B o denproben.
III. M ehrm alig während 42 Tagen eingefrorene und entfrorene Proben. In den so behandelten Bodenproben im lufttrockenen Zustand, w urde die Zusam m ensetzung der H um usfraktionen nach der Methode von Tiurin, abgeändert von Ponom ariewa sow ie nach der M ethode von K ononowa und B ieltschikow a, bestim m t. D ie erhaltenen Ergebnisse erw iesen, dass die beiden Methoden dieselbe R egelm ässigkeit der D ifferenzierung und Veränderung der Hum usfraktionen in A bhängigkeit von dem Pflanzenbestand und der Probenbehandlung, in Rahm en
70 M. Birecki, J. Gastoł
desselben Bodentypes, aufw eisen. Der Gesam m tgehalt der H um infraktion und der Hum insäuren sowie auch die berechneten H um usindexe (die V erhältnisse H um in säuren: Fulvosäuren und Humine: Fulvosäuren) zeigen, dass sow ohl im Boden, in den m echanisch beständigen A ggregaten und in den w asserstabilen Krüm eln unter Luzernegrasgem isch, der Humus m ehr stabil ist als unter K artoffeln. Der Humus in Aggregaten und K rüm eln unter dem untersuchten Pflanzenbestand ist m ehr stabil, als im untersuchten Gesamtoden.
B ei einm aligen Einfrieren die Stabilität des Humus in den untersuchten Böden, Aggregaten und Krüm eln erhöht sich. Das m ehrm alige Ein- und Entfrieren führt dagegen zur Dispersion und Erhöhung der B ew eglichkeit des Humus. D ie berechneten H um usindexe kennzeichnen am bessten die Veränderung der Zu sam m ensetzung der Hum usfraktionen in A bhängigkeit von dem Pflanzenbestand und der Einfrierung.
M . B I R E C K I , J . G A S T O Ł
INFLUENCE DES PLANTES ET DE LA CONGÉLATION DU SOL SUR LA COMPOSITION DES FRACTIONS D ’HUMUS DU SOL
ET DE SES AGRÉGATS
C h a i r e d é C u l t u r e d e s P l a n t s d e S o l U n i v e r s i t é A g r o n o m i q u e d e V a r s o v i e R é s u m é
Les études ont été réalisées avec les échantillons de la couche labourée du sol (type ’’terre noire”), prélevés en autom ne I960 et 1961 dans le champ de la ferm e expérim entale ’’C hylice” de l ’U niversité Agronomique de V arsovie. Les éch an tillons provenaient dessols sous les pommes de terre, sous le m élange de lucerne avec les herbes ainsi que sous la jachère. On a préparé les échantillons:
I — non congelés,
II — congelés une seule fois à la tem perature — 10 ° pendant 42 jours, III — congelés plusieures fois et dégelés pendant 42 jours.
Les échantillons des sols traités de cette façon étaient déssechés à l’air et puis soumis à la déterm ination des fractions d’humus d’après la m éthode [1] de Tiurin m odifiée par Ponom ariewa ainsi que la m éthode [2] de K ononowa et B ielichowa.
Les résultats obtenus avec les deux m éthodes perm ettent de constater dans tous les cas la m êm e régularité de différentiation des fractions d’humus, suivant la végétation et la congélation dans le cadre d’un m êm e type pédologique.
Le teneur totale en fractions d’hum ines et de acides hum iques ainsi que les indicateurs de l ’humus perm ettent de constater que le niveau de substance hum i- que et le plus élevé dans les échantillons du sol provenant de la lucerne. Le carac tère de substance hum ique des aggrégats et des grum eaux de parcelles etudiées est plus stable en com paraison avec l’humus du sol en général.
Une seule congélation conduit au tenforcem ent d’humus des aggrégats et des grum eaux, tandis que plusieures congélations et décongélations augm entent la dis persion et la m obilité d’humus.
Les indicateurs calculés caractérisent les changem ent de la composition des fractions d’hum us suivant la végétation et la congélation du sol.
E ffect of Vegetation and freezing on hum ic and soil aggregates 71
M . B I R E C K I , J . G A S T O Ł
SKŁAD FRAKCYJNY PRÓCHNICY W GLEBIE I AGREGATÓW GLEBOWYCH W ZALEŻNOŚCI OD ROŚLINNOŚCI I ZAMROŻENIA
K a t e d r a O g ó l n e j U p r a w y R o l i i R o ś l i n , S G G W W a r s z a w a
S t r e s z c z e n i e
Badania przeprowadzono na próbkach glebow ych pobranych z w arstw y ornej jesienią I960 i 1961 r. z doświadczenia polowego, założonego na glebie typu czarna ziem ia średnia, w Chylicach, pow. Grodzisk M azowiecki. Próbki glebow e spod ziem niaków, ugoru i lucerny z traw am i poddano w laboratorium trzem sposobom traktow ania:
I — próby w yjściow e — bez zamrożenia,
II — próby jednorazowo zamrożone w tem peraturze — 10 °C przez 42 dni, III — próby kilkakrotnie zamrażane i odmrażane w ciągu 42 dni.
W tak potraktowanych próbach glebow ych po doprowadzeniu ich do p ow ietrz nie suchego stanu oznaczono skład frakcyjny próchnicy metodą Tiurina w m odyfi kacji Ponom ariewej oraz metodą Kononowej i B ielczikow ej. Otrzymane w yniki w ykazały, że obie m etody dają podobną praw idłow ość w zakresie zróżnicowania i zm ian frak cji próchnicy w zależności od roślinności i zamrożenia w obrębie jed nego typu glebowego. Ogólna zawartość frak cji hum in i kw asów hum inow ych oraz obliczone w skaźniki próchniczne wskazują, że zarówno w glebie, agregatach m echanicznie trw ałych i gruzełkach wodoodpornych pod lucerną z traw am i jest w ięcej próchnicy o ustabilizow anej budowie niż pod ziem niakam i. Próchnica agre gatów i gruzełków pod badanym i obiektam i jest bardziej utrwalona niż w glebie rozpatrywanej jako całość. W czasie jednokrotnego zam rażania następuje um oc nienie próchnicy badanych próbek gleby, agregatów i gruzełków, natom iast w cza sie kilkakrotnego zamrażania i odmrażania następuje dyspersja i w zrost ruchliw ości próchnicy. Obliczone w skaźniki próchniczne najlepiej charakteryzują zmiany frak cyjnego składu próchnicy w zależności od roślinności i zamrażania.
М . Б И Р Е Ц К И , Ю . Г А С Т О Л Д ВЛИЯНИЕ КУЛЬТУРНЫХ РАСТЕНИЙ И МОРОЗА НА ФРАКЦИОННЫЙ СОСТАВ ГУМУСА В ПОЧВЕ И В ПОЧВЕННЫХ АГРЕГАТАХ К а ф е д р а О б щ е г о З е м л е д е л и я В а р ш а в с к о й С е л ь с к о х о з я й с т в е н н о й А к а д е м и и Р е з ю м е Исследовали почвенные образцы отобранные осенью I960 и 1961 гг. из па хотного слоя темноцветной средней почвы в полевых опытах проводимых на опытной станции Хылице возле Варшавы. Почвенные образцы, взятые из под картофеля, черного пара и смеси лю церны со знаками (пятилетнего пользования) подвергали в лабораторных усло виях следующим способам замораживания: I) контроль — без замораживания, II) однократное замораживание в температуре —10°С 42-суточное,
72 M. Birecki, J. Gastoł III) несколько-кратное в течение 42 суток замораживание с последующим оттаиванием. Затем почвенные образцы доводили до воздуш но сухого состояния и опре деляли в них фракционный состав гумуса по методу Тюрина в модификации В. Пономаревой, а такж е по методу Кононовой и Бельчиковой. Из полученных результатов следует, что в пределах одного почвенного типа оба метода показывают схож ую закономерность в диф ференциации и изменении фракционного состава гумуса, в зависимости от растений и замораживания. Общее содержание фракции гуминов и гуминовых кислот, а такж е вычисленные гумусные индексы (соотношение гуминовых кислот к фульвокислотам и зуми- нов к фульвокислотам) показали, что под смесью люцерны со злаком как в почве так и в механически прочных агрегатах и водопрочных комках было больше гумуса со стабильным строением, чем под картофелем. Гумус механически прочных агрегатов и водопрочных комков под исследованными растениями такж е оказался более стабильным, чем гумус почвы. Во время однократного замораживания наступило закрепление гумуса, в то время как при многократном замораживании и оттаивании наступает дисперсия и увеличение подвижности гуминовых веществ. Вычисленные гумусные индексы наиболее точно характеризуют изменение фракционного состава гумуса, в за висимости от растений и способа замораживания.
