THE EFFECT OF GAMMA IRRADIATIONON PROPERTIES OF SOIL HUMIC ACIDSJOANNA STRZELECKA, SŁAWOMIR S. GONET** J. Strzelecka, MSc, Prof. S.S. Gonet, DSc, Department of Soil Science,
Nicolaus Copernicus University in Toruń, ul. Gagarina 9, 87-100 Toruń, Poland
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Plan of the presentation
 Introduction and purpose of the work Material and methods
 Results and discussion
 Conclusions
 References
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

www.montmorillonite.info/Page%2051.jpg

Fig.1. Selected properties of the humic substances.
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Humic acids (HAs)

Mean residence time of HAs in soil is evaluate on about
Humic Substances in Ecosystems 8, Šoporňa13.-17.9.2009
Slovakia
1000years.

Fig.2. The electromagnetic spectrum.

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Source:http://students.umf.maine.edu/~delanonh/images/4845f11eadc9a.jpg

Gamma radiation

paperaluminumFig.3. Ability to penetrate theafla, beta and gamma radiation
by different shields.
lead

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Source: upload.wikimedia.org/wikipedia/commons/thumb/...

Gammaradiation

Purpose of the work
The purpose of this study was to identify
possibly broad diagnosis of nature, depositionand effect scale of gamma radiation on soil
humic acids (Has) and the attempt atanswering the question whether resistant tochemical and microbial decomposition, HAs
are also resistant to gamma radiation, as
seen primarily through the relationship ofdose – effect.
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Material and methods
Symbol of HAsample
LAS

PULTOROrigin
HA extracted from O-horizon of Albic Arenosol
under the pine trees
HA extracted from A-horizon of the Haplic Luvisol
used for agriculture
HA extracted from layer 0-30 of Eutri-FibricHistosol

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Humic acids samples

γγ(0 kGy)Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia(160 kGy)

Gamma radiation
LAS

PUL

TOR

Source of γ : 60Co
Radiation dose : 160 kGy*Time of irradiation: 1,5 months* D = Ē  m-1 [Gy][Gy] = [J  kg-1]

Fig.4. Radiation device RChMγ, commonly known as ”cobalt bomb“.

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

For both series HAs were estimated: elemental analysis, spectra within the scope of the visible andultraviolet light (UV-VIS), infrared spectra (IR), nuclear magnetic resonance spectra (NMR).
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Results and discussion

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Elemental analysis
Table 1. Elemental analysis (in atomic percentage; calculated on ash-free drymass) values of atomic ratios of internal oxidation (ω) of humic acids.
atomic %Sample

LAS

PUL

TOR

Variant

H:C

N:C

O:C

O:H

ω

C

H

N

O

0 kGy

35.4

40.7

2.0

21.9

1.15

0.06

0.62

0.54 0.257

160 kGy

35.5

40.5

1.9

22.1

1.14

0.05

0.62

0.54 0.265

0 kGy

32.8

43.7

2.8

20.7

1.33

0.09

0.63

0.47 0.186

160 kGy

32.9

43.4

2.8

20.8

1.320.090.63

0.47 0.201

0 kGy

35.0

42.3

1.8

20.9

1.210.05

0.59

0.49 0.140160 kGy

34.9

42.3

1.8

21.0

1.210.05

0.60

0.50 0.146

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

UV-VIS
Table 2. Absorbance values in UV-VIS region and quotient of absorbancevalues of humic acids solutions.
SampleVariant

A280

A465

A665

A2/4

A2/6

A4/6

0 kGy

0.970

0.174 0.0306

5.6

31.7

5.7

160 kGy

0.881

0.159 0.0280

5.5

31.5

5.70 kGy

0.829

0.149 0.0298

5.6

27.8

5.0

160 kGy

0.814

0.144 0.0288

5.7

28.3

5.00 kGy

0.845

0.150 0.0301

5.6

28.1

5.0

160 kGy

0.911

0.164 0.0326

5.6

27.9

5.0LAS

PUL

TOR

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

IRFig.5. IR – spectra of Has.
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

NMR
Table 3. Results (in % of peak area) from integration of the 13C-NMR
CP/MAS spectra of humic acids.
Chemicalshift(ppm)
0 – 45LAS0 kGy
160 kGy
20.923.9HA sample
PUL
0 kGy
160 kGy
27.7
27.1

TOR
0 kGy
160 kGy
22.8
23.5

45 – 65

14.2

12.7

15.3

13.7

12.2

11.5

65 – 95

12.5

9.0

12.4

10.8

11.6

10.5

95 – 110

5.5

3.5

2.7

3.5

4.3

4.6

110 – 145

20.2

20.8

17.9

20.1

18.7

17.3

145 – 165

9.5

10.2

6.5

6.7

9.6

9.7

165 – 180

10.0

11.2

12.2

14.0

13.5

13.9

180 – 220

7.1

8.6

5.4

4.3

7.3

9.0

∝

0.85

0.85

0.57

0.66

0.81

0.77

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

250200150100500-50[ppm]250200150100500-50

Fig.6. 13C-NMR CP/MAS spectra of humic acids samples „LAS” before (left) andafter gamma
irradiation(right).
Humic Substancesin Ecosystems
8, Šoporňa 13.-17.9.2009 Slovakia

Conclusions
 HAs are resistant to gamma irradiation at a doseof 160 kGy,
 irradiation of HAs samples did not have influence

on elemental composition and course of spectra
within the scope of the visible and ultraviolet lightand infrared one and 13C-NMR CP/MAS spectra, structure and properties of HAs depend on theirsource of origin (type of soil).
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

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współczesnego środowiska na organizm człowieka, PWN, Warszawa
Gonet S.S., Markiewicz M. (eds.): Rola materii organicznej w środowisku, PTSH,Wrocław, 152, 2007
Jaracz P., Promieniowanie jonizujące w środowisku człowieka, WUW, Warszawa,115, 2001
Kowaliński S., Gonet S.S.: Materia organiczna gleb, [w:] Zawadzki S. (eds.),
Gleboznawstwo, PWRiL, Warszawa, 1999
Silva W.T.L., Silva S.C., Oliveira Rezende M.O., Influence of gamma-radiation on
the behavior of humic acids from peat and tropical soil, Journal of Radioanalyticaland Nuclear Chemistry, 222 (1-2), 29-34, 1997
Silverstein R.M., Webster F.X., Kiemle D.J.: Spektroskopowe metody identyfikacjizwiązków organicznych, Wyd. Nauk. PWN, Warszawa, 502, 2007
Szymański W.: Elementy nauki o promieniowaniu jądrowym dla kierunków
ochrony środowiska, Wydawnictwo Uniwersytetu Mikołaja Kopernika, Toruń, 307,
1999
Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia

Humic Substances in Ecosystems 8, Šoporňa 13.-17.9.2009 Slovakia