¡ôLi Xin, reporter of China Environment News

As the summer vacation begins, local monitoring agencies along the coast have started annual marine garbage monitoring work. "Marine ecological environment monitoring covers marine environmental quality monitoring, marine ecological monitoring, special monitoring, etc., one of which is the monitoring of marine garbage." Zhang Weiwei, director of the Monitoring Department of the National Marine Environmental Monitoring Center, told reporters.

The 2023 China Marine Ecological Environment Bulletin shows that the average number of floating garbage visually observed at sea is 23 per square kilometer, the average number of beach garbage is 46,311 per square kilometer, and the average number of seabed garbage is 1,201 per square kilometer, of which plastic garbage accounts for 89.8%, 79.1%, and 75.4% respectively.

"According to the monitoring results, the main type of marine garbage is plastic, which accounts for the highest proportion." Zhang Weiwei believes that although the average density of marine garbage and offshore microplastics in China's coastal waters is at a medium-low level compared with similar international survey results, if effective measures are not taken, plastic garbage will continue to accumulate in the marine environment, which will not only affect the people's experience of clear water and clean beaches, but also harm the marine ecosystem. The derived microplastic problems even pose potential risks to human health.

Marine plastic garbage comes from a wide range of sources, with the highest proportion in 58 coastal waters

Marine plastic garbage is the focus and difficulty of marine garbage pollution prevention and control, and it is also one of the pollution problems that the public feels most directly and reflects most strongly. As an emerging hotspot, the impact of marine plastic garbage and microplastics on the marine ecosystem has received widespread attention in recent years.

"By material type, marine garbage can be divided into plastic, rubber, glass, metal, fabric, wood products, and paper products. According to the monitoring data of 58 near-shore waters, the main type of marine garbage is plastic garbage, accounting for about 80%." Zhang Weiwei introduced.

The sources of marine plastic garbage are complex and can enter the ocean through river input, coastal tourism, marine aquaculture, ship transportation, etc. Under the influence of ultraviolet rays, waves, wind, etc., large pieces of plastic garbage will gradually age and break down into microplastics with a diameter of less than 5 mm.

Marine plastic garbage is not only large in quantity, but also widely distributed. They can be found on beaches, sea surfaces, and seabeds. The monitoring methods for marine plastic garbage in different regions are different. Beach plastic garbage monitoring is carried out by sampling at sections set up on the beach. In recent years, drone remote sensing marine garbage monitoring has also been gradually promoted and applied. Monitoring of floating garbage on the sea surface is generally carried out through visual monitoring and sampling by sea surface trawl. "The technical requirements for monitoring floating garbage on the sea surface are relatively high. The monitoring ship needs to maintain a low speed and use special marine garbage sampling equipment to trawle on the side of the ship. After the samples are collected, they are taken back to the laboratory for classification, and the density, quantity, quality, etc. of the garbage are further analyzed." Zhang Weiwei said.

Depending on the size specifications, marine plastic garbage can be divided into extra-large pieces, large pieces, medium pieces and small pieces. "Larger garbage is easier to monitor, such as plastic bottles and packaging bags, which can be identified with the naked eye. But for smaller microplastics, the samples must be digested and density separated in the experiment, and then the chemical composition is identified by means of infrared spectroscopy analysis." Zhang Weiwei said.

Fine monitoring to achieve no obvious plastic garbage in key coastal areas

The "14th Five-Year Plan" Plastic Pollution Control Action Plan proposes to carry out monitoring and investigation of marine plastic garbage and microplastics; implement special cleaning of plastic garbage in bays, estuaries, beaches and other areas, promote coastal cities and counties to establish a long-term mechanism for cleaning up marine plastic garbage, and keep key coastal areas free of obvious plastic garbage.

Recently, the Ministry of Ecology and Environment and four other departments jointly issued the "Action Plan for Cleaning Marine Garbage in Coastal Cities", proposing a three-year dragnet marine garbage cleanup operation in 65 bays adjacent to urban built-up areas in coastal cities and towns in China, and requiring the ecological environment departments (bureaus) of coastal provinces (autonomous regions, municipalities directly under the central government) to guide coastal cities and towns to strengthen marine garbage investigation and survey work. "At the same time, we also encourage areas with conditions to carry out marine garbage monitoring work in county-level waters."

As an important part of the third marine pollution baseline survey, in 2024, coastal areas launched a detailed bay survey, setting up a total of 283 beach garbage on-site survey points and 336 sea surface floating garbage survey points in hot spots where the public is close to the sea. "We also carried out drone remote sensing surveys in hot spots where the public is close to the sea." Zhang Weiwei said.

As the investigation of marine garbage in coastal areas continues to go deeper and more practical, some places have gradually explored new models and means for the prevention and control of marine garbage pollution.

Fuzhou City, Fujian Province, took the lead in building China's first marine garbage image video monitoring network system. By deploying cameras on the beach, it has achieved real-time monitoring of the location, quantity and type of garbage, providing support and guarantee for the normalization of marine garbage prevention and control.

Haikou City, Hainan Province has established a "marine sanitation" system. Staff use drones to conduct inspections at sea, include nearshore waters and beach areas in the daily cleaning scope, efficiently identify the location and type of marine floating garbage, expand the scope of garbage cleaning, and improve the accuracy of identification.

The modern monitoring system is accelerating to help improve the quality and efficiency of beautiful bays

Zhang Weiwei introduced that China's monitoring capabilities in marine plastic garbage are at the international leading level. When formulating the monitoring technical guidelines, it benchmarks the relevant technical specifications of the United Nations Environment Program to achieve monitoring standards and international connection to ensure that the monitoring data are comparable.

How to achieve "monitoring first, sensitive monitoring, and accurate monitoring" and better play the supporting, leading and service role of marine environmental monitoring in marine ecological environmental protection is an inevitable requirement for adapting to the development of the new era. The Implementation Opinions on Accelerating the Establishment of a Modern Ecological Environment Monitoring System points out that it is necessary to accelerate the digital transformation of ecological environment monitoring, innovate monitoring methods, and further enhance the representativeness and coverage of the monitoring network.

"Marine garbage monitoring is a long-term and lasting project. In the future, we will continue to improve the quality and efficiency of monitoring, do a good job in monitoring data analysis, and provide important support for the construction of beautiful bays." Zhang Weiwei introduced that in the "Reference Indicators for the Construction of Beautiful Bays (Trial)", marine garbage is also included as a reference indicator to build a beautiful bay with "clear water, clean beaches, fish and gulls flying, and harmony between people and the sea". The clear water and clean beaches include the task of managing marine plastic garbage.

Plastic Industry Video