In the past two decades, the residual amount of conventional LDPE plastic film in the soil has increased year by year. Whether the LDPE plastic film can be replaced by a fully biodegradable plastic film is to seek to solve the pollution of the residual plastic film on dry farmland while maintaining high productivity. Basic scientific issues in agricultural development. In response to this key issue, Professor Xiong Youcai's team designed a landfill experiment with different levels of residual film in corn farmland soil from 2018 to 2019. A total of 7 different gradient treatments were set up to compare the differences between conventional LDPE mulch film and fully biodegradable film. . The results showed that no matter what type of residual film was added, the higher the amount of residual film in the soil, the more significant the effect on soil maize productivity and soil physical properties. The effect of plastic residual film on the physical and chemical properties of soil bulk density , porosity, moisture and nutrients was most obvious in the high residue treatment. The presence of residual film changed soil water storage dynamics and final crop water consumption, which in turn affected maize biomass accumulation and final yield throughout the growth period. Soil organic carbon did not change significantly, but total nitrogen increased significantly. In this case, soil C/N decreased, and the effect tended to be aggravated with the increase of residual film addition amount. The microbial biomass C and N decreased with increasing residues, while the microbial biomass C/N ratio did not change significantly after two years of landfill treatment.
Source: https://doi.org/10.1016/j.jhazmat.2021.125521
Recently, the Journal of Hazardous Materials published online Kiprotich Koskei and Alex Ndolo Munyasya, the first authors of , and Prof. Xiong Youcai. Corresponding author's research paper, titled "Effects of increased plastic film residues on soil properties and crop productivity in agro-ecosystem", investigates the effects of long-term mulching of conventional low-density polyethylene (LDPE) mulch and biodegradable mulch on corn farmland The impact of the ecosystem has been systematically observed, evaluated and compared, which has important pioneering value in the research on the production benefits and environmental effects of degradable plastic film enrichment.
This study mainly revealed the mechanism of the influence of two types of residual film on the productivity of farmland maize from the perspective of soil. The above phenomenon occurs because residual film debris can physically hinder the growth of crop roots and soil capillary action. Since the full biodegradable residual film is partially degradable in the soil, the water flow performance of the soil profile is better than that of the plots with the LDPE residual film added. Therefore, other related parameters such as water utilization, nutrient cycling, microbial metabolism , etc. may perform better in the fully biodegradable residual film treatment compared with LPDE. In conclusion, the negative effects of LDPE residual films on soil properties and maize productivity were higher than those of fully biodegradable residual films, but their adverse effects on maize fields were similar.
This research has important pioneering significance in the field of residual film pollution control and dryland agroecology. The first authors Kiprotich Koskei and Alex Ndolo Munyasya are foreign graduate students of Lanzhou University. They have published one of the few high-quality research papers so far. author. The publication of this paper is an important indicator for the improvement of the quality of international student training in Lanzhou University.The research was supported by the National "Ten Thousand Talents Program" Leading Talents Support Fund (2018-29-5), the Open Fund Project of the State Key Laboratory of Grassland Agro-Ecosystems, and the Ministry of Education Overseas Famous Teacher Project (Ms2011LZDX059). About the first author of
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Kiprotich Koskei, male, Kenya nationality, born in 1990, ecology major , master student of Lanzhou University (graduated in 2020). In 2017, he was recommended by the President of Kenya Agricultural University (JKUAT) and selected by the China Scholarship Council. The student went to Lanzhou University to study for a master's degree. The research direction is agroecology , and he was taught by Professor Xiong Youcai. effects and mechanism studies.
Text: Wang Shan Wang Pengyang
Editor: Fan Zhuqing
Editor in charge: Xu Wenyan
