Dostopnost kovin v onesnaženih tleh po remediaciji z metodo stabilizacije : doktorska disertacija

Tica, Dragana (author), Leštan, Domen (mentor), Veber, Marjan (comentor)

Z delom, predstavljenim v doktorski disertaciji, je bila raziskana učinkovitost stabilizacije oz. imobilizacije potencialno strupenih kovin (PSK;Pb, Zn, Cu in Cd) z dodajanjem hidroksiapatita (HA) in komercialnega stabilizanta Slovakita tlem, onesnaženimi s PSK. Raziskan je tudi vpliv živih okoljskih dejavnikov (deževniških vrst L. terrestris in D. veneta, kot modelni vrsti) na usodo imobiliziranih PSK v remediranih tleh. Z različnimi ekstrakcijskimi testi je bilo dokazano, da se je z dodajanjem aditivov tlom (5% w/w) znižala biodostopnost in mobilnost PSK (ekstrakcije z dietilentriaminpentaocetno in etilendiamintetraocetno kislino), posledično tudi fitodostopnost PSK v tleh (ekstrakcije z CaCl2 in NH4OAc), in da so PSK prešle iz bolj mobilnih v manj mobilne ali nemobilne frakcije (sekvenčna ekstrakcija). Znižanje oralne biodostopnosti PSK v remediranih tleh je bilo dokazano na primeru dodajanja 5 % HA tlem (Unified BARGE Method). Stabilizacija tal je izboljšala funkcionalnost in kakovost tal; Ž- glukozidazein dehidrogenaze (DHA) ter z glukozo inducirano dihanje (zvišano do5,2- kratnika po dodatku aditivov) so se izkazali kot najobčutljivejši parametri pri spremembah pH, CEC in potencialne biodostopnosti PSK ter posledično kot primerni potencialni indikatorji kakovosti tal. Dostopnost PSK je bila zaradi delovanja deževnikov povečana s čimer je bil končni učinek stabilizacije zmanjšan, obenem pa je bilo izboljšano funkcionalno stanje tal (porast z glukozo induciranega dihanja in DHA aktivnosti). Za povečanje učinkovitosti stabilizacije onesnaženih tal sta bili po dodatku HA dodani tri natrijeva sol [S,S]-EDDS in melasa.

• Language: Slovenian
• Keywords: potencialno strupene kovine, biodostopnost, onesnaženost tal, stabilizacija, hidroksiapatit, Slovakit, kalcijev polisulfid, funkcionalnost tal, encimska aktivnost, deževniki, disertacije
• Work type: Doctoral dissertation
• Typology: 2.08 - Doctoral Dissertation
• Organization: BF - Biotechnical Faculty
• Publisher: [D. Tica]
• Year: 2013
• Number of pages: XIV, 102 f.
• PID: 20.500.12556/RUL-76687
• UDC: 631.4:502/504:543.2(043.3)=163.6
• COBISS.SI-ID: 786039
• Publication date in RUL: 30.12.2015

TICA, Dragana, 2013, Dostopnost kovin v onesnaženih tleh po remediaciji z metodo stabilizacije : doktorska disertacija [online]. Doctoral dissertation. D. Tica. [Accessed 20 March 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=76687

Secondary language

• Language: English
• Title: Accessibility of metals in contaminated soils after remediation with stabilization method

Abstract

The aim of doctoral work was to evaluate the effectiveness of stabilization i.e. imobilization of potentially toxic metals (PTMs; Pb, Zn, Cu and Cd) by adding hydroxyapatite (HA) and commercial stabilizant Slovakite to soil contaminated with PTMs. The impact of biotic environmental factors (two earthworms species L. terrestris and D. veneta, as a model species) on the fate of imobilised PTMs in remediated soil was also considered. By means of different extraction tests it was determined that both aditives (5 % w/w each) were successful in lowering PTMs bioaccessibility and mobility (extraction tests with dietylenetriaminepentaacetic acid and ethylenediaminetetraacetic acid), phytoaccessibility (extractions with 0,01 M CaCl2 and NH4OAc) as well as in converting the most labile PTMs chemical forms into less labile soil fractions (sequential extraction). Oral bioaccessibility of PTMs was effectively reduced by the addition of 5 % hydroxyapatite (in gastrointestinal fraction concentration of Pb was reduced from 4 to 14 times after remediation), which was determined by UBM (Unified BARGE Method). At the same time functionality and quality of soil were improved due to soil stabilization; activity of Ž- glucosidase and dehydrogenase (DHA) as well as glucose-induced respiration (increased even 5,2 times after remediation) were most sensitive parameters to pH, CEC and PTM potential bioaccessibility changes in the soil, demonstrating their potential as indicators of soil quality. General increase of PTMs bioaccessibility was noticed after earthwormʼs incubation, indicating that the stabilization effect may decrease over time. On the other hand soil functioning after remediation was improved due to earthwormʼs activity. It was reflected in the increased induced respiration rate and increased DHA activity. We also tried to improve soil stabilization by adding tri-sodium salt of [S,S]- ethylenediaminedisuccinate and molasses after soil mixing with hydroxyapatite.

• Keywords: potentially toxic metals, heavy metals, bioaccessibility, soil pollution, remediation, stabilization, hydroxyapatite, Slovakite, calcium polysulfide, soil functionality, enzyme activity, earthworms