Estimation Of Plastic Waste Inputs From Chinese Coastal Land Areas Into The Ocean

With the development of China's economy and the improvement of human consumption level,the production of plastic waste is increasing.Plastics,due to its difficult degradation characteristics,coupled with inappropriate human treatment,flowed into the ocean through rivers and human activities at sea.In 2010.up to 4.8 million tons to 12.7 million tons of plastic waste flowed into the ocean.According to statistics,marine plastic garbage accounts for 60-80%of all garbage worldwide,Such a huge amount of plastic waste has caused great harm to the marine ecosystem.Large volume of plastic will entangle marine organisms,causing drowning,suffocation,death or being eaten by other organisms.Toxic substances enriched in plastic waste and chemical substances produced in its degradation process have endangered ecosystems through biological chains,and ultimately threaten human health.In this study,multiple linear regression models were used to estimate plastic waste production in land areas within 50 km of China's coast.On the basis of this,the amount of plastic waste entering into large quantities is estimated.Taking Shanghai as an example,based on the plastic waste output from 2000 to 2013,the plastic waste output from 2019 to 2030 is predicted.The results show that:(1)The output of plastic waste in the land area of 50 km coastal area of China can be divided into four levels:The output of plastic waste in Guangzhou,Dong guan and Foshan ranges from 1.2 million tons to 1.4 million tons.The output of plastic waste in Shanghai,Suzhou,Ningbo,Shenzhen,Zhuhai and other cities ranges from 0.9 million tons to 1.2 million tons.Binzhou,Wei fang,Lianyungang,Tianjin,Dalian and other cities have 0.7-0.9 million tons of plastic waste;Tangshan,Rizhao,Ningde.Haikou and other cities have 0.5-0.6 million tons of plastic waste.There are also individual cities that cannot estimate production because of lack of data.In addition,the consumption structure of residents is also an important factor.The more developed the commodity economy,the more disposable waste will be produced.(2)The output of plastic waste is positively correlated with the degree of urban economic development.The more developed the urban economy,the more people there are,the more waste they produce.For example,in Guangzhou,Shanghai,Jiaxing.Ningbo.Shenzhen,Zhuhai and Suzhou,the output of plastic waste is more than 900,000 tons.Most of these cities belong to the first and second-tier cities with high economic level,large population and large consumption.For example,Weihai,Taizhou,Qinhuangdao,Rizhao.Zhanjiang,Ningde,Jieyang,Tangshan and other cities mostly belong to the third and fourth-tier cities.Their economic level is lower than that of the first and second-tier cities,and their resident consumption level is lower,so the amount of plastic waste generated is lower than that of the economically developed areas.On the other hand,the proportion of urban waste plastics imports in China is also very large,and most of them are concentrated in southeast coastal cities,mainly in Guangdong,Zhejiang,Jiangsu and other places.(3)According to the economic conditions of these cities,the perfection of plastic waste management facilities,the characteristics of waste recycling and foreign research methods,the amount of plastic waste entering the land area within 50 km of the coast of China is calculated by 1.7%,3.2%and 4.6%.The main factors affecting the amount of plastic waste into the sea are as follows:the first is that climate conditions,topography,vegetation,waste management facilities and so on.It is difficult to estimate the amount of plastic waste entering into the sea accurately.The second,based on the different levels of municipal garbage management.Some municipal garbage management systems and domestic waste disposal infrastructure is perfect.Garbage classification and recycling efficiency is high and the amount of garbage entering into large quantities is relatively small,so suitable for small proportion,some cities are backward in economy,which garbage treatment measures and management systems are insufficient.Plastic garbage into the sea is large,so suitable for large proportion.The third,plastic waste is recyclable solid waste.There are many people engaged in plastic waste recycling in cities of our country,and the utilization rate of plastic waste recycling is generally high.The total amount of plastic waste is multiplied by four proportions;the amount of plastic waste into the sea can be obtained.The results show that according to the three conversion rates,the amount of plastic waste is 35.2×104 t,66.8x 104 t and 96.Ox104 t,respectively.Because plastic has the characteristics of recycling,more people are engaged in plastic waste recycling.Plastic waste is classified and recycled from the source.China is also an importer of plastic waste before 2018,and the comprehensive utilization rate of plastic waste is generally high.According to the national conditions of municipal waste management in China and related literature,the conversion rate of plastic waste entering into ocean in China is closer to 1.7%.(4)Taking Shanghai as an example,based on the known output of plastic waste from 2000 to 2013,the output of plastic waste from 2019 to 2030 is predicted.The results show that Shanghai's plastic waste output reached 1.217 million tons in 2013.On this basis,the future output of plastic waste in Shanghai increased from 1.53 million tons in 2019 to 2.036 million tons in 2030,with a growth rate of 33%.If human beings do not control the management of plastic products and plastic garbage reasonably,the output of plastic garbage will increase on a large scale,thus threatening the marine ecosystem and human health.