Technological watch

Polyethylene film mulch (PM) is a kind of widely used technology to improve crop yields worldwide; however, because of a problem related with plastic residual pollution, it has gradually been replaced by biodegradable plastic film mulch (BDP). Although BDP has helped to solve the plastic residual pollution, its consequences in terms of greenhouse gas (GHG) emissions have rarely been revealed. Related knowledge is important for forming low-carbon development strategies for the plastic industry and agriculture. The objective of this study is to evaluate the influence of BDP on GHG emissions at different stages of its life cycle, and determine whether replacing polyethylene (PE) film with BDP film is a helpful way to reduce national GHG emissions. The results of this study suggest that the application of BDP improved the GHG emissions associated with agricultural inputs, but induced lower GHG emissions at the growing stage and the waste disposal stage, and resulted in lower total area-scale GHG emissions. Compared to the no mulch (NM) cultivation system, the yield-scale carbon footprint was reduced in both the PM and BDP cultivation systems, which meant that both PM and BDP produced lower GHG emissions than NM for the production of the same amount of grain. It was concluded that BDP is not only a measure to control the problem of plastic residue pollution in agriculture, but it can also mitigate the GHG emissions.