Preliminary Findings of Polypropylene Carbonate (PPC) Plastic Film Mulching Effects on the Soil Microbial Community

Abstract

The farmland residual film pollution caused by traditional PE film has an adverse impact on crops and the environment. Polypropylene carbonate (PPC) film is a fully biodegradable film that can alleviate “white pollution”. In this study, the soil physicochemical properties and the composition and function of the soil community of FM (PPC film mulching) and CK (no film) treatments were determined to explore the effect of PPC film mulching on soil and the soil microbial community. Furthermore, the microorganisms at different time periods during the degradation of PPC mulch film were also analyzed. The results showed that film mulching increased soil pH but decreased the contents of EC and SOC, and there was no significant difference in the contents of AP and AK. The relative abundance of the phyla Acidobacteria was increased with film mulching, and the relative abundance of the genera MB_A2_108 also increased in the film mulched soil. Among the soil physicochemical properties, pH and SOC were the most important factors leading to changes in the composition of the bacterial and fungal communities. PPC film mulching had no significant effect on soil microbial community abundance and diversity. In addition, Pseudomonas, Flavobacterium, and Rhizobacter were dominant in the degradation of PPC film. Our research results provide a scientific theoretical basis for soil safety and the large-scale use of PPC biodegradable mulching films and a research foundation for the degradation of PPC plastics.

Research and Application of Polypropylene Carbonate Composite Materials: A Review

“…PPC is degraded by micro-organisms in the soil environment. Although degraded PPC increases the pH of soil, it does not significantly affect the richness of the microbial community in the soil [ 126 ]. Nevertheless, PPC degrades slowly under normal conditions and does not meet usage requirements.…”

Ternary copolymers from carbon dioxide, cyclohexane dicarboxylic anhydride, and propylene oxide with improved thermal and mechanical properties

“…The 1 H and 13 C NMR spectra were recorded on a Bruker DPX-400 spectrometer using deuterated chloroform (CDCl 3 ) as the solvent and tetramethylsilane as an internal standard. Differential scanning calorimetry S C H E M E 1 Ternary copolymerization of CO 2 , PO, and CH (DSC) was measured on a Mettler-Toledo 822 e thermal analyzer in a dry nitrogen environment.…”

“…Copolymerization of CO 2 with epoxides to generate aliphatic polycarbonate is a promising route. Poly(propylene carbonate) (PPC), synthesized by alternating copolymerization of CO 2 and propylene oxide (PO), shows exceptional properties, such as biodegradability, biocompatibility, and gas barrier, 11,12 attracting particular interest in the field of biomedicine, food packaging, and agriculture 12–15 . However, PPC is deficient in low glass transition temperature ( T g ), poor thermal stability, and low mechanical properties (e.g., low Young's modulus and tensile strength), which restrict its wide applications 14–16 …”

“…in the field of biomedicine, food packaging, and agriculture. [12][13][14][15] However, PPC is deficient in low glass transition temperature (T g ), poor thermal stability, and low mechanical properties (e.g., low Young's modulus and tensile strength), which restrict its wide applications. [14][15][16] Four strategies have been developed to improve PPC, (1) terpolymerization to introduce the third monomers through synthesis, [17][18][19][20][21][22][23] (2) crosslinking to form an inter-bonded structure, [24][25][26][27] (3) chain extending 28 or capping 29 of the hydroxyl end groups, and (4) physical blending with nanofillers or other polymers.…”

Effects of Film Mulching on Soil Microbial Diversity and Community Structure in the Maize Root Zone under Drip Irrigation in Northwest China

“…Film mulching can significantly increase soil microbial diversity and bacterial abundance [16]; it can also significantly increase the α-diversity of soil bacteria and have a crucial effect on shaping the soil bacterial community [17]. Bacterial networks in filmmulched soils are more complex and have a higher index of microbial community diversity than those in non-mulched soils [18]. It has also been shown that film mulching agricultural soils accelerates the succession of microbial communities in the soil and affects the stability and diversity of the soil microbial community structure [19].…”