关键词: 玉米, 不同厚度地膜, 连续覆盖, 土壤物理性状, 地膜残留量

Abstract: To investigate the effects of different thickness plastic film mulching on soil physical properties and plastic film residues in soil, this paper carried out 4 continuouse years studies by adopting a field trial. The results showed that: ①soil compactness and soil bulk density decreased in 0~40 cm soil layer as the thickness of plastic film increased. The soil bulk density for treatments of 0.010 mm and 0.012 mm decreased by 1.25% and 2.43%, respectively, while, that of 0.006 mm increased by 0.76% compared to 0.008 mm（CK）. ②From planting to bellbottom, daily average soil temperature for treatments of 0.006 mm, 0.010 mm and 0.012 mm increased by -0.90℃, 0.23℃ and 0.40℃ in 0~5 cm and -0.50℃, 0.19℃ and 0.28℃ in 5~10 cm soil, compared to that of the CK. The temperature increasing effect gradually weakened with the maize growing. ③In 25 d after irrigation, the soil water contents for treatments of 0.006 mm, 0.008 mm, 0.010 mm and 0.012 mm were 166.73 mm, 170.42 mm, 190.00 mm and 195.97 mm, respectively, decreased by 46.81%, 45.75%, 39.32% and 37.62%, respectively, compared to that  irrigation after 5 d  in 0~100 cm soil layer. ④In 0~30 cm soil layer, the amount of film residue in shallow soil was significantly more than that in deep soil, the film blocks with area of less than 4 cm2 were significantly more than that with area of 4~25 cm2 and above 25 cm2. The total accumulative film residues reached 79.03 kg/hm2, 57.68 kg/hm2, 50.32 kg/hm2, 53.58 kg/hm2 in 4 years for treatments of 0.006 mm, 0.008 mm, 0.010 mm and 0.012 mm. The residues for treatment of 0.006 mm were significantly higher than that of the CK. The plastic film with more than 0.008 mm of thickness was suggested to be used widely in crop production by comprehensive analysis of soil physical properties and influence of film residues.

Key words: maize, different plastic film thickness, continuous mulching, soil physical property, film residues