doktorska disertacija
Simon Gluhar (Author), Domen Leštan (Mentor)

Abstract

Namen doktorske dizertacije je prispevati k boljšemu razumevanju tehnologije pranja tal s kelatnim ligandom EDTA, raziskati vpliv EDTA na tla in širše okolje in s tem opredeliti, ali lahko to tehnologijo označimo kot zeleno in trajnostno rešitev za remediacijo tal, onesnaženih s potencialno strupenimi elementi. Z dodajanjem ničvalentnega železa v tla med postopkom remediacije smo preprečili emisije ostankov kelatov EDTA s strupenimi elementi iz tal že 6 dni po remediaciji pH-nevtralnih karbonatnih tal in 7 dni po remediaciji kislih tal. Raziskali smo vpliv remediacije tal na razgradnjo herbicidov, kot pomembne funkcije kmetijskih tal. S pomočjo FOMC modela smo določili vrednost DT50 za posamezne herbicide. Pri kislih tleh se je DT50 povečala pri izporoturonu za 16 %, bentazonu 21 %, mekoprop-P-ju 42 %, S-metolaklor-u 111 %. Pri karbonatnih tleh se je DT50 remediiranih tal pri mekoprop-P-ju povečala za 3 %, medtem ko se je pri ostalih treh znižala za do 30 %. Vedno pa je bila DT50 manjša kot povprečna, objavljena v literaturi. Nadalje smo učinkovitost in varnost uporabe EDTA primerjali z biorazgradljivimi kelatnimi ligandi GLDA, EDDS in IDS. S kvantitativno analizo, pri kateri smo uporabili osem različnih za remediacijo relevantnih kategorij, je pokazala na vrstni red primernosti: EDTA> GLDA> IDS> EDDS. Remediirana tla so omogočala podobno rast ajde (F. esculentum) in celo boljšo rast kitajskega zelja (B. rapa) v primerjavi z originalnimi tlemi. Aktivnosti stresnih encimov antioksidativnega preventivnega sistema v kitajskem zelju in fizikalne lastnosti tal so bile podobne pri remediiranih in originalnih tleh. Podobno je bilo tudi funkcioniranje tal, ki smo ga ocenili preko merjena mikrobnega dihanja in aktivnosti talnih encimov, ki sodelujejo pri kroženju C, N in P v tleh. Tla, remediirana z EDTA, so v primerjavi s tlemi, remediiranimi z biorazgradljivimi kelatnimi ligandi, funkcionirala bolje. Vpliv remediacije na tla in rastline: ajda, špinača, radič, motovilec, solata, česen, čebula, por, korenje in koleraba, smo preučili tudi v realnih razmerah na demonstracijskem vrtu z 9 gredicami, vsaka s 1,75 t zračno suhih tal. Kljub temu, da so bila pred remediacijo tla nadpovprečno onesnažena (Pb 1854, Zn 3833 in Cd 21 mg kg–1), smo pri večini rastlin uspeli zmanjšati koncentracijo Pb pod zakonsko določeno mejo, razen pri ajdi in korenju. Koncentracije Cd so bile pri večini rastlin pod ali blizu zakonsko določene meje, le pri korenju, špinači in radiču so bile meje prekoračene. Remediacija z EDTA je zmanjšala vsebnost Pb, Zn in Cd v tleh za 71, 28 in 53 %, ni pa imela večjega pomembnega vpliva na lastnosti in funkcioniranje tal.

Keywords

remediacija tal;EDTA;sekundarne emisije EDTA;razpad herbicidov v remediiranih tleh;biorazgradljivi kelatorji;doktorske disertacije;

Data

Language: Slovenian
Year of publishing:
Typology: 2.08 - Doctoral Dissertation
Organization: UL BF - Biotechnical Faculty
Publisher: [S. Gluhar]
UDC: 502.174:627.533:632.954(043.3)
COBISS: 35482883 Link will open in a new window
Views: 483
Downloads: 88
Average score: 0 (0 votes)
Metadata: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Other data

Secondary language: English
Secondary title: Environmental risks after remediation of soils contaminated with potentially toxic elements using chelating agent
Secondary abstract: The aim of the doctoral dissertation was to contribute to a better understanding of soil washing technology using the chelate ligand EDTA, to investigate the effects of EDTA on soil and the environment in a broader sense, and to determine whether this technology can be considered a green and sustainable solution for the remediation of soil contaminated with potentially toxic elements. By adding zero-valent iron to the soil during the remediation process, we prevented the emission of residues of EDTA chelates with toxic elements from the soil as early as 6 days after the remediation of pH-neutral carbonate soils and 7 days after the remediation of acidic soils. We investigated the impact of soil remediation on herbicide degradation as an important function of agricultural soil. Using the FOMC model, we determined the DT50 value for individual herbicides. In acidic soils, DT50 increased by 16% with isporoturon, 21% with bentazone, 42% with mecoprop-P and 111% with S-metolachlor. In carbonate soils, the DT50 value of remediation soils for mecoprop-P increased by 3%, while it decreased by up to 30% for the other three herbicides. However, the DT50 was always lower than the average value published in the literature. In addition, the efficacy and safety of EDTA was compared with the efficacy and safety of biodegradable chelate ligands GLDA, EDDS, and IDS. A quantitative analysis, in which we used eight different remediation-relevant categories, showed the order of suitability: EDTA> GLDA> IDS> EDDS. The remediated soil allowed a similar growth of buckwheat (F. esculentum) and an even better growth of Chinese cabbage (B. rapa) compared to the original soil. The activity of the stress enzymes of the antioxidant prevention system in Chinese cabbage and the physical properties of the soil were similar in the remediated and original soils. Similarly, soil function was assessed by measuring microbial respiration and the activity of soil enzymes involved in the circulation of C, N, and P in soil. Soils remediated with EDTA performed better compared to soils remediated with biodegradable chelate ligands. The effects of remediation on soil and plants: buckwheat, spinach, radicchio, lamb`s lettuce, lettuce, garlic, onion, leek, carrot, and kohlrabi were also examined under realistic conditions in a demonstration garden with 9 raised beds, each with 1.75 t of air-dry soil. Despite the fact that the soil had an above-average contamination before the remediation (Pb 1854, Zn 3833 and Cd 21 mg kg–1), we succeeded in reducing the Pb concentration in most plants, with the exception of buckwheat and carrots, to below the legal limit. Cd concentrations in most plants were below or near the legal limit in most plants, only carrots, spinach, and chicory exceeded the limits. Remediation with EDTA reduced the Pb, Zn, and Cd contents in soil by 71, 28, and 53%, respectively, but had no significant effect on soil properties and function.
Secondary keywords: soil remediation;secondary emissions of EDTA;dissipation of herbicides in remedited soil;biodegradable chelators;
Type (COBISS): Doctoral dissertation
Study programme: 0
Embargo end date (OpenAIRE): 1970-01-01
Thesis comment: Univ. v Ljubljani, Biotehniška fak.
Pages: XI f., 86 str., [2] str. pril.
ID: 12118321