Abstract:

As the governed grain producing area in Inner Mongolia, the north foot of Yinshan Mountain has faced the problem of farmland residual film pollution. Biodegradable plastic film is widely accepted to be an important approach to solve the farmland remnants of membrane fouling. It is significant to study biodegradable plastic film (PBAT/PLA) in increasing temperature and preserving soil moisture, degrading performance and its effects on crop yield and economic benefits for the farmland residual film pollution prevention, ecological environment and the green and high-quality development of agriculture. In this paper, three kinds of PBAT/PLA biodegradable plastic films, one kind of common polyethylene plastic (PE) mulch films, and bare land treatment (labeled as F1, F2, F3, CK, and OF) were carried out in potato experiment. The results showed that soil temperature gradually increased from May to June with a peak in the middle of July to August, and then decreased to a lower level. Compared with PE film, no significant difference was detected in average soil temperature and soil water content in potato germination and seedling stage (May to June) (P>0.05), which could meet the growth demand of potato in early growth stage. F1 and F2 treatments entered the induction stage 42-56 days after mulching, and all the crops in that season could enter the crushing stage before harvest, and the degradation rate was 34.2%-42.7%. After landfilled for 365 days, the degradation basically completed. From 68 to 84 days after mulching, F3 treatment entered the induction period, and the degradation rate of crops is 15.5%-28.0% before harvest, and the degradation is basically completed 365-540 days after landfilled. The yields and economic benefits of the three kinds of biodegradable film mulching crops were 49.6-58.5 t∙hm^-2 and 15600-24200 yuan∙hm^-2, respectively, and insignificant difference was found from those of PE films (P>0.05). The crop yield and economic benefit of F1 and F2 treatments were significantly higher than those of bare land (P<0.05), in which the crop yield was increased by 36.9% and 38.3%, and the economic benefit increased by 14300 and 15000 yuan∙hm^-2, respectively. Compared with PE films, crop yield increased by 4.1% and 5.2%, respectively. According to the comprehensive evaluation of degradation performance and crop yield, F1 and F2 treatments had better degradation performance, improved crop yield and protected cultivated land ecological environment in the northern foot of Yinshan Mountain in Inner Mongolia.

Key words: north foot of Yinshan Mountain in Inner Mongolia, potato, biodegradable plastic film, degradation rate, yield, benefit

摘要：

内蒙古阴山北麓作为内蒙古的粮食主产区,普遍存在农田残膜污染的问题。应用全生物降解地膜是解决农田残膜污染的重要途径,研究聚己二酸对苯二甲酸丁二醇酯/聚乳酸（PBAT/PLA）全生物降解地膜增温保墒性能、降解性能及其产量经济效益对于解决农田残膜污染、保护生态环境、实现农业绿色高质量发展具有重要意义。本研究在马铃薯田开展了3种PBAT/PLA全生物降解地膜、1种普通PE地膜和裸地处理（分别标记为F1、F2、F3、CK和OF）的覆膜栽培试验和降解地膜填埋试验。结果表明,各覆膜处理5—6月土壤温度逐渐升高,7—8月中旬达到作物生育期峰值,随后降低至较低水平。与普通PE地膜相比,3种全生物降解地膜在马铃薯发芽、幼苗期（5—6月）平均土壤温度和土壤含水量未形成显著差异（P>0.05）,能够满足马铃薯生育前期的生长需求。F1和F2处理在作物覆膜后42—56 d进入诱导期,当季作物收获前均能进入破碎期,降解率为34.21%—42.74%,填埋365 d后基本降解完全;F3处理覆膜后68—84 d进入诱导期,作物收获前降解率为15.47%—28.04%,填埋365—540 d基本降解完全。3种全生物降解地膜作物产量和经济效益分别为49.64—58.53 t∙hm^-2和1.6×10⁴—2.4×10⁴ yuan∙hm^-2,未与普通PE地膜形成显著差异（P>0.05）。F1和F2处理作物产量和经济效益显著高于裸地（P<0.05）,其中作物产量分别提高36.85%和38.27%,经济效益分别增加1.43×10⁴ yuan∙hm^-2和1.5×10⁴ yuan∙hm^-2;与普通PE地膜相比,作物产量分别增加4.1%和5.18%。根据降解性能和作物产量综合评价,在内蒙古阴山北麓马铃薯种植条件下,F1和F2处理具有较好的降解性能,且在提高作物产量、保护耕地生态环境方面具有较好效果。

关键词: 内蒙古阴山北麓, 马铃薯, 全生物降解地膜, 降解率, 产量, 效益