Agricultural Films to Be Replaced by Biodegradable Products Made from Fallen Leaves

by Jeong Ilwoong

Published 30 Apr.2026 08:28(KST)

Biodegradable products made from fallen leaves are emerging as a potential alternative to conventional agricultural films. Agricultural films are widely used in rural areas to suppress weed growth and retain soil moisture. However, most agricultural films are made of plastic, making post-use collection difficult. Residual materials left in the soil are also known to cause environmental pollution, highlighting the need for alternative products.

(From top left to bottom) Professor Jae-wook Myung of the Department of Civil and Environmental Engineering, Dr. Choi Sae-hyung, doctoral candidate Yongjun Cho, master's candidate Hoseong Moon, (right) doctoral candidate Pham Thanh Trung Ninh. KAIST

On April 30, KAIST announced that a research team led by Professor Jae Wook Myung of the Department of Civil and Environmental Engineering has developed an eco-friendly agricultural "mulch film" made from fallen leaves.

Mulch film is a material commonly used in the agricultural sector to cover soil. The development of mulch film from fallen leaves is significant in that it transforms non-edible biomass, which was previously discarded as waste, into high-value functional materials.

Most mulch films currently in use are made of polyethylene (PE, a representative petroleum-based plastic), making post-use collection challenging and causing environmental issues due to residual microplastics left in the soil.

The research team utilized fallen leaves as a way to replace PE-based mulch films with biodegradable products. They extracted nanocellulose from fallen leaves using a deep eutectic solvent composed of citric acid and choline chloride, and then combined this nanocellulose with biodegradable polymer polyvinyl alcohol to produce a composite film.

In particular, the entire manufacturing process was carried out using water as the solvent rather than harmful organic solvents, further enhancing the eco-friendliness of the product.

The "fallen leaf film" developed by the research team exhibited excellent performance in blocking ultraviolet (UVA and UVB) rays and preventing soil moisture loss (moisture retention), making it suitable for practical use in agricultural settings. Ryegrass grown with this film even showed better growth when using the fallen leaf film compared to other films.

Conceptual diagram of the recycling use of fallen leaf film. KAIST

The biodegradability, which is a prerequisite for addressing soil pollution, was also confirmed to be excellent. In an actual soil biodegradation experiment, 34.4% of the fallen leaf film decomposed within 115 days, a faster rate than existing biodegradable films.

Furthermore, there was no plant toxicity (adverse effects on plant germination or growth) observed during the decomposition process, indicating that the film does not negatively affect the germination and early growth of ryegrass and Brassica rapa.

Professor Myung stated, "This research is meaningful because it goes beyond the simple disposal of fallen leaves and transforms them into functional materials that can protect the agricultural environment. The process, which is based on fallen leaves and water-resources that do not compete with food sources-shows promise as a sustainable technology for replacing agricultural plastics in the future."

Meanwhile, Pham Thanh Trung Ninh, a doctoral candidate in the Department of Civil and Environmental Engineering, participated as the first author of this research. The findings were recently published in the international academic journal "Green Chemistry," which covers the fields of chemistry and environmental science.