Study On The Characteristic Of Plastic Film Residue And Its Effect On Maize Growth In Typical Regions

Plastic film which has been becoming one of the most important materials for agricultural production is used widely in agriculture and promotes the agricultural development and farmers'income. But because of the limitation of plastic film's material,there are much plastic film residue in soil which causes pollution.Plastic film residue has affected on soil's quality,crop's growth,use of straw,animal husbandry,agro-mechanization and ecology seriously.There are two parts in our research: investigate the plastic film residue in the typical regions in North and Northwest China to find out the characteristics according to collect and analyse the plastic film residue;to find out the harm of plastic film residue on maize in field.We choose two typical regions-Handan in Hebei Province and Shihezi in Xinjiang Province to investigate the plastic film residue in cotton field and sample and analyse the data.The results show that pollution in Shihezi is more serious than in Handan and the average weight of plastic film residue are in 59.1 kg·ha^-1 and 103.4 kg·ha^-1 in Handan and in 200.0 kg·ha^-1 and 400.0 kg·ha^-1 in Shihezi.There are regularities in plastic film residue:Pollution in these two regions are serious.Plastic film residue distribute regularly in spatio-temporal,weight,amount,configuration.Plastic film residue changes with the planting patterns and agricultural operation.The weight and amount of plastic film residue increase year by year.It concentrates in shallow layer mainly.The amount and weight of plastic film residue changes in a spatio-temporal law.There are more plastic film residue in shallow layer than in deeper layer.Different areas of plastic film residue distributes significantly and the larger is heavier than the smaller.The amount ratio of 3 kinds of plastic film residue(<4 cm²:4～25 cm²:>25 cm²) is 7:2:1.The distribution of plastic film residue changes with the turning over and ploughing the field and the plastic film residue in deeper layer increase.The total amount of plastic film residue,amount in deeper layer and the fragmentation index of plastic film residue increase after turning over.Different planting models affected on the plastic film residue in configuration,amount and weight.The experiment on plastic film residue-maize indicates that the plastic film residue affects on maize's growth and more plastic film residue affects more.It's more significantly in early stages such as seeding stage than in later stages.The effect weakens or disappears with maize grows.The hight don't changes significantly in different stages.The stem diameter decrease with the increase of plastic film residue significantly in seedling,jointing and maturity and not significantly in tasseling.The leaf area in seedling stage decrease significantly and not different in maturity.The biomass of root,stem and leaf indicates that it's obviously that more plastic film residue limit the growth of maize more.All the data aren't significantly different in later stages especially in maturity.There are not significant difference of plastic film residue's effect on 100-seed weight,ear hight,length,diameter and yield.Ear rows and row grains don't changes regularly.It is because that the root of maize in seedling stage is weaker.It's more obviously in early stages than in later stages.The maize in later stages becoming more stronger and higher resistibility.The harm of plastic film residue falls in last stages.