Abstract:

Agricultural film residues which limit crop growth and cause soil pollution become increasingly serious. Exploring the effects of agricultural film residues with different amounts on the growth of maize and soil environment can provide theoretical support for the scientific and rational use of agricultural film. In this study, the distribution of residual film in maize farmland with film mulching in Hetao irrigation region of Inner Mongolia was taken as the research object, and 6 residual film gradients were set, including 0 (CK), 75kg·ha⁻¹, 150kg·ha⁻¹, 300kg·ha⁻¹, 450kg·ha⁻¹ and 600kg·ha⁻¹, and the effects of different amounts of the agricultural film residues on maize yield and its components, root weight and taproot number, soil moisture content and bulk density were analyzed. The results showed that: (1) there was a negative correlation between the amount of film residues and the yield of maize, and there was a significant difference in the yield when the amount of film residues exceeded 300kg·ha⁻¹ (P<0.05). With the increase of film residues, the bald tip of maize increased, and the 100-grain weight decreased significantly (P<0.05). (2) The increase of the film residues reduced the root quality and taproot numbers of maize, which were not conductive to the growth and development of the root system, and the ability of the root system to absorb water and nutrients from the soil decreased. (3) The film residues hindered the transport of soil water, soil water seeped slowly when the amount of film residues reached 300−450kg·ha⁻¹, and the film residues over 600kg·ha⁻¹ hindered the migration of soil capillary water and the infiltration of precipitation. Therefore, the use of scientific and reasonable ways to control soil residual film pollution control and recycle plastic film to reduce plastic film residues in the soil is helpful to promote the improvement of maize yield and soil quality, and realize the green and sustainable development of agriculture.

Key words: Agricultural film residue, Maize root, Soil environment