Abstract:
Using methods of questionnaire and field survey, we analyzed mulching film utilization, collecting and residue pollution in peanut field of Henan Province.The results showed that mulching film in peanut field was mostly with 0.004-0.006 mm of thickness with 45 kg·hm
-2.Most peanut farmers collected residual film by hand-picking.The average residual film amount was within 15.0-40.0 kg·hm
-2 in 0-30 cm depth of peanut field, which was lower than the national standard of 75 kg·hm
-2(GB/T 25413-2010) at the first pollution level.The amount of residual film increased with the mulching years.The total amount of residual film in peanut field was 15.0, 26.9 and 40.0 kg·hm
-2 for 5 years, 10 years and 15 years, respectively.Film residuals were mainly distributed in the 0-10 cm depth of soil, and majority of them was in the sizes of 4-25 cm
2 or >25 cm
2.Based on the national standard of 75 kg·hm
-2 at the first pollution level, and mulching plastic film amount of 45 kg·hm
-2 and residual ratio of 5.92%-6.65% annualy, we estimated that the safety years of film application in peanut field of Henan province was 25-29 years.