Biodegradable Liquid Slow-Release Mulch Film Based on Bamboo Residue for Selenium-Enriched Crop Cultivation

). Soil temperature and humidity increased by 0.4 to 2.1 °C and 0.5% to 2.8%, respectively, in the soil covered with PVA@CMC/QL compared to those in other controls, thereby confirming its exceptional moisture retention and insulation capabilities. PVA@CMC/QL combined remarkable weed suppression with only 13.3% weed germination under the mulch. Optimal rhizome growth of pak choi seedlings was observed under the PVA@CMC/QL cover, as demonstrated by the planting of both pak choi seedlings and weeds. Roots and stems increased by 3.8 ± 0.3 and 1.2 ± 0.3 cm, respectively. The weed suppression mechanism of PVA@CMC/QL was explained through the lens of density functional theory. In addition, the selenium content of pak choi seedlings under PVA@CMC/QL cover could reach 28.5 μg/kg, making the mulch film both degradable and highly reusable. This work not only improved the value-added utilization of bamboo residues but also gave new insight into the research on multifunctional bamboo-plastic mulch film.