Mulch film residue contamination in typical areas of North China and countermeasures

Characteristics of the mulch film contamination in typical areas of North China was primarily investigated. The investigation results showed that the amount of mulch film residues were respectively 5.629, 7.369 and 2.822 kg·hm^－2 in the soil of the plastic film greenhouse, vegetable field and crop field for the sampled areas of Hebei Province, and the level of mulch residues were respectively 4.169, 3.682 and 2.430 kg·hm^－2 in the soil of plastic film greenhouse, vegetable field and crop field for the sampled areas of Heilongjiang Province. There were significant differences in the average amount of mulch residues among the different sample sites, but all the average residue levels in the soil sample site using plastic film were obviously higher than those in the soil sample site where plastic film was not applied. Besides the crop field, the mulch film residues were greater in the soil samples of the other two fields of Hebei Province than in the soil samples of the other two fields of Heilongjiang Province. The sizes of film residues were mostly within about 10～15 cm for the two areas. Based on the status of mulch film contamination, the countermeasures were suggested.