ASSESSING EFFICIENCY OF REMEDIATION IN A RADIOACTIVELY CONTAMINATED TERRITORY BY PLOUGHING SOIL

The paper provides results of assessed remediation efficiency in a radioactively contaminated territory by ploughing soil. Efficiency assessment of three soil cultivation technologies was made. Research has shown efficiency in ploughing soil in terms of reduced surface contamination of the territory. EDR levels and levels of β-particle flux density after reploughing of research spots, on the average, have been reduced by 56% and 87% respectively. Radionuclide transfer from the topsoil to underlying horizons can be observed. Maximum activity concentrations at some research spots can be found in soil layers of 20-25 cm. A change in the soil texture is found at remediated spots and in humus content which may point to both deflationary processes and moving silt fractions and humus into the soil depth under gravity and affected by precipitation. The paper also considers the issue of radionuclide carry-away by plants onto the soil daylight surface and the impact by the type of plant root system on this process; an assessment is given to the effect by remediation technologies selected on the process of remediated spots overgrowing with vegetation. On the whole, it is found that soil ploughing to a depth of 30 cm is the most preferable technology with a backset of 180° followed by sowing with steppe vegetation.

1. IAEA TECDOC 745 Rukovodstvo po primeneniyu kontrmer v sel'skom khozyaystve v sluchae avariynogo vybrosa v okruzhayushchuyu sredu, MAGATE, Avstriya, 1994, P. 31.

2. Zhelyazko V.I. Melioratsiya, rekul'tivatsiya i okhrana zemel' / V. I. Zhelyazko, T. D. Lagun. - Gorki: BGSKhA, 2016. - 276 p.: posobie il. ISBN 978-985-467-617-3.

3. Karamysheva Z.V. Botanicheskaya geografiya stepnoy chasti Tsentral'nogo Kazakhstana /Z.V. Karamysheva, E.I. Rachkovskaya // Leningrad: Nauka, 1973. - 277p.

4. Otchet o nauchno-tekhnicheskoy deyatel'nosti Instituta radiatsionnoy bezopasnosti i ekologii NYaTs RK, vypolnennyy v ramkakh meropriyatiya 0346 “Razvitie atomnoy energetiki v Respublike Kazakhstan” za 20102011 gody: IRBE NYaTs RK; ruk. Lukashenko S.N. -Kurchatov, 2011.- 98 p. Otchet NTP, 2011.

5. Panitskiy A.V. Osobennosti vertikal'nogo raspredeleniya radionuklidov v pochvakh uslovno-chistoy territorii byv-shego Semipalatinskogo ispytatel'nogo poligona / A.V. Panitskiy, S.N. Lukashenko, R.Yu. Magasheva // Radiatsionnaya biologiya. Radioekologiya. - 2016. -Vol. 56. - No. 6. - P. 623-638.

6. Polevaya geobotanika. - M.- L.: Nauka, 1959-1976, in 5 volumes. Vol. 1 - 498 p., Vol. 2 - 500 p., Vol. 3 - 530 p., Vol. 4 - 336 p., Vol. 5 - 320 p.

7. Metodologiya otsenki sostoyaniya i kartografirovaniya ekosistem v ekstremal'nykh usloviyakh. - Pushchino: ONTI PNTs RAN, 1993. - 202 p.

8. Kamelin R.V. Florotsenotipy rastitel'nosti Mongol'skoy Narodnoy Respubliki // Botanicheskiy zhurnal. Vol. 72. No. 12. P. 1580-1594.

9. Serebryakov I.G. Zhiznennye formy vysshikh rasteniy i ikh izuchenie //Polevaya geobotanika. - Moscow - Leningrad, 1964. Vol. 3. P. 146-205.

10. Bykov B.A. Dominanty rastitel'nogo pokrova Sovetskogo Soyuza // Alma-Ata. Nauka. 1960-1965. in 3 volumes. V. 1 - 314 p., Vol. 2 - 435 p., Vol. 3 - 461 p.

11. Dzhanpeisov R.D. Vliyanie erozii i deflyatsii na strukturu pochvennogo pokrova polupustyn' i pustyn' Kazakhstana / Dzhanpeisov R.D., Zonov G.V., Smagulov T. // Izd. Nauka, Alma-Ata, 1990, P. 28.

12. Sultanova B.M. Vosstanovlenie antropogenno narushen-noy stepnoy rastitel'nosti Kazakhstana // Materialy konf. “Razvitie geobotaniki: istoriya i sovremennost'”. - Sankt-Peterburg, 2011. P. 113-114.