On The Current Status And Prevention & Control Countermeasures Of Plastic Film Residue Contamination In The Hetao Irrigation Area Of Inner Mongolia

Plastic film mulching technology,as a major planting measure in arid and semi-arid areas,has made a significant contribution to food security in China.However,the problems of unreasonable plastic film use and unfavorable recycling,coupled with the fact that plastic film itself is fragile and difficult to degrade,have led to the emergence of serious plastic film residue contamination,which has caused great harm to soil health and crop growth.In view of this,it is necessary to have an accurate and comprehensive picture of residual film pollution in agricultural fields,as it is of great significance for agricultural production security and ecological environmental protection.Given the lack of an overall survey of plastic film residues in the river-loop irrigation area,this study aims to address this issue by combining questionnaire surveys,field sampling surveys and remote sensing techniques to investigate the current status of residual film pollution in the river-loop irrigation area.A comprehensive analysis of the relationship between film year,film crop,soil texture,recycling method,plastic film residue and net plastic film residue in the year is conducted,and reasonable suggestions for future plastic film pollution prevention and control are proposed.The results of the study showed that:（1）The residues of plastic film in the Hetao Irrigation Area of Inner Mongolia range from 18.20～418.60 kg·hm^-2with a mean value of 131.11 kg·hm^-2.Among them,the residues in Urad Qianqi are the highest with a mean value of 164.70 kg·hm^-2,followed by Linhe District with 128.15 kg·hm^-2.The residual amount was 164.70 kg·hm^-2,followed by Linhe District with 128.15 kg·hm^-2,both of which belong to the moderately polluted area;while the residual amounts in Hanggin Rear Banner,Wuyuan County and Dengkou County are 117.56 kg·hm^-2,110.23 kg·hm^-2and 86.8 kg·hm^-2,respectively,all of which belong to the lightly polluted area.In addition,the years of film mulching 0～10 years,10～20 years,20～30 years and more than 30 years accounted for 28.12%,28.18%,24.63%and 19.07%of the total area of farmland.（2）The amount of plastic film residue is influenced by the age of film mulching,crop type and recycling or not.It is found that the amount of plastic film residue is significantly（P<0.05）affected by plastic film mulching age,which shows that the degree of residual film contamination increased with film mulching age.In the Hetao Irrigation Area,maize and sunflower have the largest area and thus are the main cover crops.The plastic film residue in the maize area is 132.77 kg·hm^-2,which is larger than that in the sunflower area(127.88 kg·hm^-2).The important factor affecting the amount of plastic film residue in Hetao Irrigation Area is whether plastic film was recycled or not.The recovery rate of plastic film in the study area is only 38.10%,and the average residual amount of plastic film in the recovered plots is 108.28 kg·hm^-2,which is lightly polluted and significantly lower than the moderate pollution(145.03 kg·hm^-2)in the non-recovered plots.Among them,the residual amount of plastic film is the most serious in the plots with sandy loam texture(153.84 kg·hm^-2).（3）It is necessary to improve the market monitoring system in the Hetao Irrigation Area and to promote effective ways of recycling film residues.For the government,consideration should be given to increasing the number of relevant policies and regulations and related subsidies,as well as promoting environmental protection through multiple channels.In addition,recycling outlets should be established in accordance with each county,and film recycling machines should be introduced.In this way,plastic film residues can be managed from the source of production,production process,sales process and management in many aspects to minimize the pollution caused by plastic film.In this thesis,the current status of plastic film residues in typical mulch planting areas of Hetao Irrigation Area is mapped,and the main influencing factors of plastic film residues are clarified,which provides some theoretical reference and scientific basis for scientific planning and management of film mulching planting.Through this,it helps to recycle used plastic film in Hetao Irrigation Area and promote the green and sustainable development of agriculture in Hetao Irrigation Area,thus responding to the construction of national ecological civilization.