E L IG IU SZ R O SZY K
LEAD IN SOME V E R Y -FIN E SAND Y SO ILS O F THE LOW ER SIL E SIA
D ep a rtm en t of A g ricu ltu ra l C h em istry, C ollege of A g ricu ltu re, W roclaw . H ead — Prof. Dr. K. B o ra ty ń sk i
The m ain source p lan ts tak e up lead from are soils. L ead in soils a p p e ars in com pounds, alm ost ex clusiv ely as d iv alen t elem ent. D ue to th e dim ensions of th e ionic rad iu s of lead being a p p ro x im ate to those of th e rad ii of s tro n tiu m an d potassium , lead, th o u g h in a lim ited degree, can e n te r th e com position of ro ck -form ing m in erals as an endocry ptic a d m ix tu re . T hus it ap pears to g eth e r w ith s tro n tiu m in lim estone m inerals (apatites an d pyroxenes) or replaces potassiu m in orthoclases an d o th er m in erals. H ence its presence in all soils, alth o u g h as a ru le in sm all q u a n titie s.
R ecen tly d iffe re n t au th o rs [3, 16] point to a n o th e r source of lead, n a m e ly ex h a u st gases of engines ru n n in g on p e tro l w ith ad ditio n of te tr a e th y l lead.
T h ere have been p u b lished few p apers on th e co n ten t of lead in soils. A ccording to W i n o g r a d o w [2], its m ean co n ten t in the E uropean p a rt of th e Soviet U nion is 10 ppm . B o r k e n a nd K u l i k [2] found th e co n ten t of lead in th e soils of th e A ltai region to oscillate from 30 to
50 ppm . A p p ro x im ate v alues (14— 96 ppm) w ere obtained by P r i n c e [8]
fo r th e soils of N ew Je rse y , U.S., S w e i n a nd M i t c h e l l [14] for S co ttish soils, an d F i l i p o v i c , S t a n k o v i c and D u s i с [4] for th e soils of A lv a lija d istric t, Y ugoslavia. A ccording to these au th o rs, in soils situ a te d on o re-b earin g deposits th e to ta l co n ten t of th is m icroele m en t can reach up to abo ut 500 ppm . F in n ish soils are poorer in lead com pounds, th e m ean c o n ten t of lead in th em being 16 ppm , according to V u o r i n e n [15].
O nly few au th o rs ex am in ed th e c o n ten t of soluble form s of lead in soils. As it re su lts fro m th e ir p ublications, th e q u a n titie s of th is elem en t
12 4 E. R oszyk
passing into d iffe re n t e x tra ctio n solutions a re r a th e r sm all and, on an
average, in m ost soils do not exceed 1 ppm [6, 7, 13].
The lack of d a ta concerning th e app earin g of lead in P olish soils
encouraged th e a u th o r to c a rry out th e follow ing in v estigations on: — th e to ta l co n ten t of lead an d its soluble form s in some Low er S ilesian soils of sim ilar m echan ical com position,
— th e dependence betw een th e to ta l an d soluble c o n ten t of lead on one han d, and o th er ph y sical and chem ical p ro p ertie s of soils on th e other.
The in v estig atio n m ate ria l w ere su rface sam ples of 3 ty p es of soils form ed out of v e ry -fin e san d y soils, n am ely 31 sam ples of black e a rth s, 31 of brow n soils an d 32 podzol soils. A t th e sam e tim e th e re h ave been exam ined 3 re p re se n ta tiv e soil p rofiles fro m each of th e soil types. For a closer d e te rm in a tio n of th e ex am in ed m a te ria l a ll th e su rface an d p rofile sam ples w ere an aly sed for m ech an ical com position, pH in 1 N KC1, sorption of m e th y l blu e = BM, c o n ten t of organic carbon an d carbonates. The ch a ra c te ristic s of th e soils have been given in e a rlie r p ap ers [1, 10].
As w ell th e to ta l con ten t of lead as its form s soluble in 2.5% acetic acid have been d e te rm in e d w ith th e sp ectro grap hic m eth od using a spec tro g ra p h of m ean dispersion Q = 24. D eterm in atio n s of lead w ere ca rrie d out p a ra lle l w ith those of o th er m icro elem en ts keeping th e sam e con ditions of ex citatio n , described in an e a rlie r p ap er [10]. The s ta n d a rd deviatio n calcu lated for n = 9 w as 9.6% for th e to ta l c o n ten t an d 6.2% for th e soluble form s.
R ESU L TS
T O T A L C O N T E N T O F L E A D
From am ong the su rface sam ples th e m ost a b u n d a n t in lead are black e a rth s (Tab. 1), 69% of th e to ta l n u m b er of sam ples containing lead from 27 to 37 ppm . In th e rem ain in g tw o soil typ es th e m ean values are ap p roxim ate. 60% of brow n soil sam ples an d 87% of podzol soil sam ples con tained lead in am ou n ts fro m 20 to 30 ppm (Fig. 1).
In se p ara te soil ty p es th e re w as not fou n d an y m a th e m a tic a lly p roved dependence b etw een th e to ta l c o n ten t of lead an d o th er physical and chem ical p ro p erties of th e soils.
On th e o th er hand , considering th e w hole e x p e rim e n tal m a te ria l w ith o u t division into soil types, n o tw ith stan d in g a little d iffe re n tia tio n in the m echanical com position of v e ry -fin e san d y soils, th e re w as fo un d a sig n ifican t positive dependence b etw een th e co n ten t of p articles less
T a b l e 1 C o n te n t o f le a d in s e v e r a l s o i l t y p e s (mean v a lu e s and o s c i l l a t i o n s ) S o i l ty p e Number o f sa m p le s T o t a l c o n t e n t ppm S o l u b i l i t y c o e f f i c i e n t S o lu b le fo rm s p p m B la c k e a r t h s 31 OJ 1 Г <Л O J O J 2.5 ^0.6 - 5.6) 0.80 (0.21 - 1.90) Brown s o i l s 31 25 (14 - 35) 2. 8 ( 0. 6 - 6 . 0 ) 0.70 (0.24 - 2.09) P o d z o l s o i l s 32 26 (18 - 45) 1.6 (0.5 - 3.4) 0.40 (0.15 - 1.43) Mean 28 2.3 0.63
Fig. 1. F req u en cy of a d eterm in ed c o n ten t of to ta l lea d in th e e x a m
in ed so il ty p es 1 — b l a c k e a r t h s , 2 — b r o w n s o i l s ,
3 — p o d z o l s o i l s
th a n 0.002 m m an d the co n ten t of lead (r = 0.53; r] n — 1 = 5.1). O th er a u th o rs, too, hav e found a h ig h er c o n cen tratio n of m icroelem ents in th e clay ey fra c tio n of d iffe re n t soils, ascrib in g it to th e sorption pro p erties of clay.
T here w as also fo un d a positive d ep endence b etw een th e to ta l co n ten t of lead and th e pH of soil (r = 0.42; r |/ n —1 = 4.1), w hich coincides w ith th e re su lts o btained by o th er a u to rs [4].
M any in v estig ato rs point to a positive d ep endence betw een th e co nten t of m ost m icroelem ents, in clu d in g lead, and th e am ount of organic carbon in soil [9, 11]. In ow n research es th is ten d e n c y w as noted, how ever not proved m a th e m a tic a lly ; it w as m ore a p p a re n t in soils of low er co nten t (brow n an d podsol) th a n in those of h ig h er co n ten t of organic carbon (black earth s).
126 E. R oszyk
In the surface sam ples th e re w as found a sig n ificant positive d ep en dence b etw een th e to ta l co n ten t of lead and th e to ta l contents of v a n a d ium , chrom ium , cobalt, nickel an d copper. No dependence w as found b etw een th e ap p earin g of lead an d m anganese.
T a b l e 2
Lead in g e n e t ic h o r iz o n s o f th e examined s o i l s (mean v a lu e s )
T o ta l c o n ten t ppm S o l u b i l i t y c o e f f i c i e n t S o lu b le forms ppm H orizon* black e a r th s brown s o i l s p o d zo l s o i l s b lack e a r th s brown s o i l s p o d zo l s o i l s black e a r th s brown s o i l s p o d zo l s o i l s I 34 24 23 4 .2 2 .9 2 .1 1 .4 2 0 .7 1 0 .6 1 II 27 20 26 6 .4 3 .0 2 .3 1 .7 4 0 .6 0 0 .6 2 I I I 26 18 22 4 .4 3 .8 2 .4 1 .1 5 0 .6 8 0 .5 3 IV 28 17 22 3 .1 1 .8 3 .4 0 .8 7 0 .3 1 0 .7 4
I - A ( 3 - lb cm) black e a r t h s , Aj_ (3 -1 5 cm) brown and p o d zo l s o i l s
II - A (3 0 -4 0 cm) black e a r t h s , В (3 0 -5 0 cm) brown s o i l s , A2 1,20-40 cm) p o d zo l s o i l s I I I - A/C (5 0 -8 0 сei) black e a r t h s , С (8 0 -9 5 cm) brown s o i l s , B (45-bO cm) p o d zo l s o i l s
IV - С (7 5 -1 1 0 cm) black e a r t h s , С (1 2 0 -1 5 0 cm) brown s o i l s , С (7 0 -1 0 0 cm) p o d zo l s o i l s
In soil p rofiles th e m ean co n te n t of to ta l lead does no t show any b ro ad e r oscillations in sev eral horizons w ith in th e com pass of a given soil ty p e (Tab. 2). Som e slig h t accu m u latio n w as found in only th e up p er lay e rs (horizon I) of th e ex am in ed profiles. A ccum u lation of lead in th e u p p e r la y e r of soils w as also no ted by H e r r m a n n [5] a nd S w e i n a nd M i t c h e l l [14].
W hen considering p a rtic u la r soil p rofiles (Fig. 2) w e fin d out th a t th e
only exception is profile No. 8 (podzol soil) in w hich lead accu m u lated
in horizon II. The n a rro w e st q u a n tita tiv e oscillations of lead in sev eral horizons of th e profiles w ere observed in brow n soils.
S O L U B L E F O R M S
The m ean so lu bility of soil lead in 2.5% acetic acid is about 2% in all soil ty p es (Tab. 1). In th e ex am in ed soil profiles th e m ean so lub ility of th is m icro elem en t did not show an y g re a te r differen ces in sev eral horizons, except horizon IV of black e a rth s an d brow n soils w here it w as p ro n o u n ced ly low er (Tab. 2).
In th e ex am ined su rface sam ples th e m ean co n ten t of soluble form s of lead in black e a rth s and b row n soils keeps at alm ost th e sam e level (T ab.l),
Fig. 2. D istrib u tio n of lea d in th e p ro files of th e ex a m in ed so ils 1 — t o t a l c o n t e n t , 2 — s o l u b l e f o r m s
w h ile in podsol soils it is pro n o u n ced ly low er, th e m ean for all ex am in ed su rface sam ples being 0.63 ppm .
The m ost fre q u e n t values foun d fo r b lack e a rth s are fro m 0.30 to 0.80 ppm (51% of th e to ta l q u a n tity of sam ples), for brow n soils from 0.40 to 0.70 ppm (61%) an d in podzol soils fro m 0.20 to 0.40 ppm (75%) (Fig. 3).
In black e a rth s som ew hat h ig h er co n ten t of soluble lead is c o rrelated w ith its g e n e ra lly h ig h er co n tent, w hile in bro w n soil it is due to h ig h er so lu b ility coefficient (Tab. 1).
S ev eral a u th o rs em phasize th e g rea t influ ence of th e organic sub stan ce co n ten t in soil upon th e so lu b ility of m icroelem ents, in clu d in g lead [12]. In th e exam in ed surface sam ples th e re w as found, th o u g h not proved, th a t th e conten ts of soluble form s of lead ten d e d to increase along w ith th e in creasin g co n ten t of organic m atte r. This dependence is m ore pro nou nced in brow n an d podsol soils ta k e n to g eth er, th a n in black earth s.
It w as also fou nd th a t the co n ten t of soluble form s of lead ten d e d to increase along w ith th e in creasin g co n ten t of silt an d clay, how ever th is dependence has not been p roved m ath em atically .
126 E. R oszyk
Fig. 3. F req u en cy of d eterm in ed so lu b le co n ten ts of so lu b le lead in th e e x a m in ed so il ty p es
1 — b l a c k e a r t h s , 2 — b r o w n s o i l s , 3 — p o d z o l s o i l s
The m ean co n ten t of soluble form s in th e soil profiles (Tab. 2) did n o t show an y sig n ifican t d iffe re n tia tio n w ith in the sam e soil typ e. The only exception w as horizon IV of black e a rth s an d brow n soils, poorer in m ore re a d ily soluble form s of lead, th is being due to a low er so lub ility coefficient in th a t horizon.
C om parison of th e co n ten t of acetic acid soluble lead in sev eral soil ty p es (Tab. 2) show s th e m ean values in all th e horizons of black e a rth s to be about tw ice h ig h er th a n those in b ro w n and podsol soils. In the ex am ined soils th e re w as not found an accu m ulatio n of soluble form s in th e su rface layer, w h a t is p a rtly co nfirm ed by S w ein and M itchell's re su lts [14].
1. T he m ean c o n ten t of to ta l lead in th e ex am in ed soils w as 28 ppm , th e black e a rth s being som ew hat m ore a b u n d a n t in th is elem en t th a n b row n and podsol soils.
2. The m ean c o n ten t of lead soluble in 2.5% acetic acid w as in th e exam in ed soils 0.63 ppm . Its m ean con ten t black e a rth s and brow n soils w as m ore or less sim ilar, only in podsol soils being pron o u n ced ly low er.
3. In th e su rface lay e r of th e exam in ed soils th e re w ere foun d sig ni fic a n t positive dependences b etw een th e to ta l co n ten t of lead an d th e co n ten t of clayey p articles, as w ell as b etw een P b an d pH in 1 N KC1.
4. In th e genetic horizons of th e ex am ined soil profiles th e re w ere found no sign ificant d ifferen ces in th e m ean to ta l co n ten t of lead as w ell as in the co n ten t of its form s soluble in 2.5% acetic acid.
REFERENCES
[I] B o r a t y ń s k i K. , R o s z y k E., R o s z y k o w a St., T y s z k i e w i c z M. , Z i ę t e c k a M.: Z aw artość p r z y sw a ja ln y c h form Cu, Mn, Mo, Zn w n ie k tó rych typ ach g leb D oln ego Ś lą sk a p o w sta ły c h na u tw orach p y ło w y ch . R oczn. Gleb., 13, z. 1, 1967, 57.
12] В о г к e n J. G., K u l i h A. A.: S o d ierża n ije m ik r o e le m ie n to w w p oczw ach a łta jsk o g o k raja. M ik roelem . w S ielsk . C hozj. i M ed., K ije v 1963.
[3] B o r k e n J. G., K u l i h A. A.: V ersch m u tzu n g von K u ltu rp fla n zen . D eu tsch e L an d w irt. P resse, 330, 1966, 35.
[4] F i l i p o v i c Z., S t a n k o v i c B., D u s i c Z.: D istrib u tio n of Cu, Pb, Zn, N i and Co in so il in rela tio n to pH ch an ges. S o il Sei., 96, 1961, 147.
[5] H e r r m a n n P.: R ech erch es g éo ch im iq u es en m a tière d’a gricu ltu re. L an d w irt. C entr., II A bt., 1966, 2823.
[6] L a k a n e n E.: On th e a n a ly sis of so lu b le trace elem en ts. A n n al. A gric. F en ia e, 1, 1962, 109.
[7] M i t c h e l l R. L.: S p ectro ch em ica l m eth o d s in so il in v e stig a tio n s. S o il Sei., 83, 1957, 1.
[8] P r i n c e A. L.: T race e le m e n ts d e liv e r in g cap acity of 10 N e w J e r se y so il ty p es as m easu red by sp ectrograp h ic a n a ly se s of so il and m atu re corn le a v e s. S o il Sei., 84, 1957, 413.
[9] R a d o w A. S., K a ń k o w A. G.: К w op rosu o k a czestw ien n o j sp ek traln oj c h a ra k teristik ie m a k ro - i m ik r o e le m ie n to w w sw ie tło k a szta n o w y ch p oczw ach w o łg o g ra d sk o j ob ła sti na p rim ierje uczchoza “G ornaja P o lja n a ”. M ik roelem . w S ielsk . Chozj. i M ed., K iev 1963.
[10] R o s z y k E.: Z aw artość form og ó ln y ch i rozp u szczaln ych w a n a d u , chrom u, m an gan u , nik lu , k ob altu i m ied zi w n iek tó ry ch g leb a ch D oln ego Ś lą sk a w y tw o rzo n y ch z g lin p y la sty c h i u tw o ró w p y ło w y ch . Zesz. N auk. W SR w e W roc ła w iu , in press.
[II] S i 11 a n p ä ä M.: T race elem en ts in fin n ish so ils as rela ted to so il te x tu r e and organ ic m a tter content. Journ. Sei. A gric. Soc. of F in lan d , 34, 1962, 34. [12] S i l l a n p ä ä M.: On th e e ff e c t of so m e so il factors on th e so lu b ility of trace
elem en ts. A grogeolog. P u b lic., 81, H elsin k i 1962.
[13] S i l l a n p ä ä M. , L a k a n e n E.: R ea d ily so lu b le tra ce elem en ts in fin n ish soils. A n n al. A gric. F en ia e, 5, 1966, 298.
[14] S w e i n D. J., M i t c h e l l R. L.: T race e lem en ts d istrib u tion in so il p ro files. J. S o il Sei., 11, 1960, 347.
[15] V u o r i n e n J.: On th e a m ou n ts of m in or ele m e n ts in fin n ish so ils. J. S ei. A gric. Soc. of F in lan d , 30, 1958, 30.
[16] W a r r e n H. V., D e l a v a u l t R. E.: L ead in sa m e food crops and trees. J. Sei. Food A gric., 13, 1962, 96.
130 E. R oszyk E. K O S Z Y K LE C O NTEN EN T D U PLO M B D A N S D ES C E R T A IN S SO L S P O U D R E U X DE B A S S E -S IL É S IE C h a i r e d e la C h i m i e A g r i c o l e d e l ’É c o l e S u p é r i e u r e d ’A g r i c u l t u r e a W r o c l a w R é s u m é
D ans 94 é c h a n tillo n s pris de la cou ch e su p e r fic ie lle et 9 p ro files des terres noires, des sols bruns et des sols p o d so liq u es p ro v en a n ts des fo rm a tio n s pou d reu ses, on a in d iq u é a v ee la m eth o d e sp ectro g ra fiq u e le co n ten en t du plom b total et d isso lu b le dans le 2,5 °/o d’acid e acidique.
On a co n sta té une p lu s gran d e q u a n tité du plom b total dans le s couches su p e r fic ie lle s des terres noires en com p araison a v ee le s m êm es cou ch es des sols bruns et des sols p od soliq u es.
L ’a n a ly se m a th ém a tiq u e a d ém on tré un e corrélation p o sitiv e en tre le co n ten t du plom b et la q u an tité des form es a rg ileu ses et le pH du sol.
L es éch a n tillo n s p ro v en a n ts des sols p od soliq u es p o sséd a ien t m oin s des form es d isso lu b les du plom b que c eu x des terres noires et des sols bruns.
On n ’a pas co n sta té des d iffe r e n c e s sig n ific a tiv e s en tre la q u a n tité to ta le du plom b et des ses fo rm es d isso lu b les en tre le s d iffé r e n ts n iv e a u x g en etiq u es des p ro fils des touts les tip es du sol, q u o i’que la co n ten a n ce m o y e n n e du plom b d iso lv é dans les d iffé r e n ts n iv e a u x g en etiq u es des terres n oires est d eu x fois p lu s gran d e que c e lle des sols bruns et des sols p od soliq u es, grace au p lu s grand c o e ffic ie n t de so lu b ilité.
E. R O S Z Y K
BLEI G EH ALT IN EIN IG E F E IN SA N D B Ö D E N DES SC H L E SIE N S
L e h r s t u h l f ü r B o d e n k u n d e , L a n d w i r t s c h a f t l i c h e H o c h s c h u l e , W r o c l a w
Z u s a m m e n f a s s u n g
In 94 P roben aus der A ck erk ru m e so w ie in 9 P ro filen des S ch w a rzerd e-, B ra u n erd e- und P o d so lty p es, g e b ild e t v o n F e in sa n d fo rm a tio n en , w u rd e der G esa m tg eh a lt an B le i s o w ie sein e lö s lic h e n F orm en in 2,5% E ssig sä u relö su n g b estim m t.
Es w u rd e fe s tg e s te llt, dass der G esa m tg eh a lt an B lei in S ch w a rzerd en etw a s höher als in B rau n erd en und P od solb od en lieg t. D ie m a th em a tisch e A n a ly s e der E rg eb n isse w ie s e in e p o sitiv e K orrelation zw isch en G esa m tg eh a lt an B lei und dem T o n g eh a lt so w ie dem p H -W ert der u n tersu ch ten B öden an.
D ie aus der A ck erk ru m e en tn o m m en en P rob en der P od solb od en sind im V erg leich zu den S ch w a rzerd e- und B rau n erd ep rob en ärm er an lö slic h e n B le i v erb in d u n g en .
A lle B o d en ty p en w ie s e n k ein e w e se n tlic h e n U n tersch ied e b etreffs der m ittleren W erte des G esa m tg eh a ltes an B lei so w ie sein er lö slic h e n F orm en in den ein zeln en g e n e tisc h e n H orizon ten der u n tersu ch ten P r o file auf. D ie M ittelw erte an lö slich en
B lei in den g e n e tisc h e n H orizon ten der S ch w a rzerd e lie g e n u n g efä h r z w e im a l höher als in den H orizon ten der. B rau n erd en und P od sole, da in S ch w arzerd en der L ö slic h k e itsk o e ffiz ie n t und der G esa m tg eh a lt an B lei h öh er sind.
E. R O S Z Y K
OŁÓW W N IEK TÓ R Y C H G LEB AC H PYŁO W Y C H I P Y L A ST Y C H D OLNEGO Ś L Ą S K A
K a t e d r a C h e m i i R o l n e j W S R , W r o c ł a w
S t r e s z c z e n i e
W 94 próbkach p o w ierzch n io w y ch i 9 p ro fila ch czarn ych ziem , gleb b ru n a tn y ch i gleb b ielico w y ch , w y tw o r z o n y c h na u tw orach p y ło w y c h i p y la sty ch , oznaczono m e todą sp ek tro g ra ficzn ą zaw artość o ło w iu ogóln ego i rozp u szczaln ego w 2,5% k w a sie o ctow ym .
W w a r stw ie w ierzch n ie j b a d a n y ch gleb stw ierd zon o n ieco w ię k sz e n a g ro m a d ze n ie ogóln ego o ło w iu w czarn ych ziem iach w p orów n an iu z g leb a m i b ru n atn ym i i b ielico w y m i. A n a liza m a tem a ty czn a całości b ad an ych gleb w y k a z a ła dodatnią zależność ogóln ej zaw artości o ło w iu od za w a rto ści części ila sty c h oraz pH (ln KC1) gleb.
P róbki p o w ierzch n io w e gleb b ie lic o w y c h są w y ra źn ie u b oższe w fo rm y rozp u sz c za ln e o ło w iu w p o ró w n a n iu z czarn ym i ziem ia m i i g leb a m i b ru n atn ym i.
W e w sz y stk ic h typ ach g le b o w y c h brak isto tn y ch różnic p om ięd zy og ó ln y m i za w a rto ścia m i o ło w iu i jego fo rm a m i rozp u szczaln ym i w p o szczeg ó ln y ch p oziom ach g en e ty c z n y c h b ad an ych p rofilów . Z u w a g i na w y ż sz y w sp ó łc z y n n ik ro zp u szcza l n ości i og'ôlnie w y ższą zaw artość śr e d n ie zaw artości o ło w iu rozp u szczaln ego w p o ziom ach g e n e ty c z n y c h czarnych ziem są około d w u k ro tn ie w y ż sz e od zaw artości w p oziom ach gleb b ru n atn ych i b ielico w y ch .
э. Р О Ш И К С ВИ Н ЕЦ В Н Е К О Т О РЫ Х П Ы Л Е ВА ТЫ Х И П Ы Л Е В И Д Н Ы Х П О Ч В А Х Н И Ж Н Е Й С И Л ЕЗИ И К а ф е д р а А г р о х и м и и В ы с ш е й С е л ь с к о х о з я й с т в е н н о й Ш к о л ы в г. В р о ц л а в Р е з ю м е В 94 п ов ер хн остн ы х о б р а зц а х и 9 р а зр е з а х ч ерн ы х, б ур н ы х и п одзол и сты х почв обр азов ан н ы х из пы леваты х и п ы л еви дн ы х о т л ож ен и й о п р едел ял и по сп ек тр огр аф и ч еск ом у м етоду со д ер ж а н и е свинца валового и растворимого в 2,5% у к сусн ой кислоте. В п ов ерхностн ом слое и ссл едов ан н ы х почв установили немного больш ее 9*
132 н ак оп лен и е валового свинца в ч ер н ы х почвах, по сравн ении с почвами буры м и и подзолисты м и. М атем атическая обработка д а н н ы х для и ссл едов ан н ы х почв в целом п ок азала п ол ож и т ел ьн ую зависим ость валового со д ер ж а н и я свинца от со д ер ж а н и я илистой ф р ак ц и и и от pH (ln KCl) почв. О бразцы с пов ерхностн ого слоя п одзол и ст ы х почв отчетливо м енее богаты растворимы ми ф орм ам и свинца, по сравнении с черны ми и буры ми почвами. Во в сех п оч в ен н ы х ти п ах нет сущ еств ен н ы х р азн и ц м е ж д у средним в а л о вым сод ер ж ан и ем свинца и его растворимы ми ф орм ам и в отдель н ы х ген ети ч е ск и х гор и зон тах и ссл едов ан н ы х п р оф и л ей . С редн ее со д ер ж а н и е растворим ого свинца в ген ети ч еск и х гор и зон тах ч е р ны х почв, всл едстви е бол ее вы сокого к о эф ф и ц и ен та растворим ости и больш ей и х обогащ енности этим элем ентом , почти д в ухк р атн о вы ш е от со д ер ж а н и я в го р и зон тах б ур ы х и п о дзол и ст ы х почв.
