Abstract
Low-density polyethylene (LDPE) and polybutylene adipate terephthalate (PBAT) are two of the main polymers composing mulch films. While LDPE is a recalcitrant material, PBAT is labelled as biodegradable. However, biodegradable mulch films are not degrading in agricultural soils as expected. We evaluated the potential of soilborne microorganisms to degrade: LDPE (LDPEp), commercial LDPE (LDPEm) and PBAT-based mulch films. We exposed mulch (1 cm2) to 15 potential treatments in low-carbon media (LC) for six months and selected four microbial treatments (M): M1: Liquid compost extract, M2: Aspergillus spp + Bacillus simplex; M3: Aspergillus Niger; M4: Aspergillus Fumigatus + Pseudomonas spp.. These were inoculated from the plastisphere to either carbon-free media (CF), another LC batch, autoclaved compost (AC), or compost (C). We also tested three abiotic treatments: 1) Non-abiotic treatment (NT); 2) UV-aged films (UV); and 3) 5% mineral oil media (MO). Weight loss (%) (WL) and Attenuated Total Reflection (ATR-FTIR) spectra were assessed. Some LDPEm treatments showed WL above 3% and oxidation signs were UV M1 and UV M2 in C, and both NT M3 and NT M4 in AC. Only MT N1 in C showed over 3% WL and ATR peak shifts for LDPEp. PBAT-based mulch. Controls did not degrade as quickly as claimed. However, UV M1 in CF, NT M4 in LC, NT M1 and NT M3 in AC, and NT M1 in C enhanced WL and showed ester bond hydrolysis, which indicates degradation. Further analyses will verify whether these results are due to fragmentation, depolymerization, and/or degradation.
Original language | English |
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Title of host publication | 2023 Book of Abstracts: Wageningen Soil Conference |
Subtitle of host publication | Working together on solutions for a sustainable world |
Place of Publication | Wageningen |
Publisher | Wageningen University & Research |
Pages | 50-50 |
Publication status | Published - 2023 |
Event | Wageningen Soil Conference 2023 - Wageningen Duration: 28 Aug 2023 → 1 Sept 2023 https://wageningensoilconference.eu/2023/ |
Conference/symposium
Conference/symposium | Wageningen Soil Conference 2023 |
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City | Wageningen |
Period | 28/08/23 → 1/09/23 |
Internet address |