At present, the invasion of alien species has become a major ecological security and biosecurity problem facing the world, and the continent is one of the countries most seriously harmed by invasive alien species in the world. In response to the increasing risk of invasive alien species, the mainland is also making countermeasures.
The report of the 20th National Congress of the Communist Party of China clearly pointed out that "strengthen biosecurity management and prevent the invasion of alien species". On August 1 this year, the "Measures for the Management of Invasive Alien Species" issued by the Ministry of Agriculture and Rural Affairs, the Ministry of Natural Resources, the Ministry of Ecology and Environment, and the General Administration of Customs were officially implemented. The Ministry of Agriculture and Rural Affairs took the lead in launching a national survey of invasive alien species this year in order to find out the bottom number, determine the risks, and promote prevention and control.
Wan Fanghao, a researcher at the Chinese Academy of Agricultural Sciences and a member of the National Key Research and Development Program "Biosecurity" key special expert group, told the Beijing News reporter that a survey of invasive alien species has been rolled out across the country, which is also the first time to conduct such a large-scale census of invasive alien species. When the census is over, the newly discovered species will be entered into the database, and the distribution area, development status of these species will be analyzed according to the big data, the economic losses will be assessed, and invasive species will be selected from them to strengthen prevention and control according to "one policy".
Increasingly frequent invasions of alien species
This summer, a "strange fish" in Ruzhou, Henan Province, broke into the human social platform. To round it up, a park drained the lake. It is about 70 centimeters long, with very hard scales, three tail fins, spots on its body, and a flat mouth that resembles a crocodile - this is the origin of its name "crocodile gar".
It is a fierce carnivorous fish from North America, extremely destructive, with hard scales and poisonous teeth that make it have few natural predators. If released into natural waters, it will prey on native species. Without food, it can also attack humans and endanger people working in the water.
Last fall, a wanted warrant in Wuhan was on the hot search, and the object of the wanted was a crazy yellow flower. It is not the "yellow flower of yesterday", but the "golden flower of Canada" with strong vitality.
In the 30s of the 20th century, it was introduced as an ornamental flower in Shanghai, Nanjing and other places. A plant has tens of thousands of seeds, which can take root and germinate even on the barren land blown down by the wind, and squeeze out the nutrients and sunlight required for the growth of other plants, resulting in the death of a large area of local plants and shrubs.
Earlier, last spring, red fire ants also caused heated discussions. This is a small brownish-red creature that lived in South America for a long time, and was introduced to China in 2004, occupying almost the entire south and even continuing further west and north. It not only infests farmland, but also attacks humans - there is a sting needle in its tail, which will have a burning tingling sensation after being stung, and pus will grow when the pain disappears.
The short video platform can also brush strings of pink balls like mulberries, or lying on paddy fields, irrigation channels, or hanging on the stems and leaves of crops. They are the eggs of Fushou snails, which videographers often crush with gloves – they have a strong reproductive rate, spread faster, spread parasitic infections and harm food crops, and have been listed as one of the first 16 most harmful alien species to invade China.
Wan Fanghao, a researcher at the Chinese Academy of Agricultural Sciences and a member of the key special expert group of the National Key Research and Development Program "Biosecurity", told the Beijing News reporter that with the accelerated development of global economic integration, the global invasion of alien species has shown a rapid growth trend, but it is far from reaching saturation, "this is not only the status quo of China, but also the status quo of the world."
China is one of the countries most seriously harmed by the invasion of alien species. According to the 2020 Communiqué on the State of China's Ecological Environment released by the Ministry of Ecology and Environment in May last year, more than 660 invasive alien species have been found across the country. Among them, 71 species have caused or have potential threats to natural ecosystems, and have been included in the List of Invasive Alien Species in China, and 219 species have invaded national nature reserves. According to media reports, among more than 660 invasive alien species, the most are invasive plants, with 370 species, accounting for more than half; It is followed by animals, with 220 species, accounting for 1/3, including a small number of fungi, prokaryotes and protists.
Prevention and control of the dilemma
The invasion of alien species is like a butterfly flapping its wings, setting off a storm thousands of miles away.
A very typical case is the water hyacinth. In the fifties and sixties of the 20th century, water hyacinth was introduced to China as pig feed, but it soon flooded and encroached on the living space of other species. Zhang Guoliang, a doctor from the Institute of Environment and Sustainable Development of the Chinese Academy of Agricultural Sciences, once told the media that the manual salvage of water hyacinth alone costs 100 million yuan per year, and the cost of chemical prevention also reaches tens of millions of yuan.
Behind the huge economic losses is the difficulty of prevention and control.
Jing Zhen, associate professor of Northeast Forestry University, pointed out in his paper that the current quarantine system of the mainland is only for some known invasive alien species, and its standards and categories in the process of quarantine and prevention rely on alien species that have caused damage, but the prevention of those species that are unknown and potentially threatening to cause damage is low.
In addition, Jing Zhen pointed out that the list of invasive alien species currently issued by the mainland has not included most of the alien species that may be threatening, only the species that have caused harm and damage to the ecological environment, the scope of the listed alien species is not comprehensive, and in the existing list of invasive alien species on the mainland, the invasive species that have caused damage are not designated according to different risk levels.
According to the 2019 Communiqué on the State of China's Ecological Environment issued by the Ministry of Ecology and Environment, more than 660 invasive alien species have been found across the country. Among them, 71 species that have threatened or have potential threats to natural ecosystems have been included in the List of Invasive Alien Species in China. However, species like the crocodile gar are not among them.
"Because of human, material and financial reasons, we can only prevent and control some key alien species now. In addition, the extent of the economic losses caused by alien species requires further information. Wan Fanghao said.
On the other hand, it is the indifference of public consciousness. The Internet has brought the world closer, and dangerous alien species may travel to the ocean as novel pets along the postal list and express delivery.
Previously, there were media reports that on the online shopping platform, someone bought a Brazilian solomon spider for 110 yuan, and the female spider of the same size was 158 yuan, and the merchant would attach a novice breeding package, which declared that "the shelves are in line with the requirements." In fact, when these "outsiders" are abandoned and released, they flow into the natural environment.
"In the past, it could take ten days and eight days for an alien species to enter, but now with the rapid development of logistics, it may arrive in half a day, and this dispersal and spread is the focus of research in the next step." Wan Fanghao pointed out.
Chinese solutions and experiences
"Our country's research on the invasion of alien species started relatively late, and the real large-scale research began at the beginning of the 21st century." Wan Fanghao introduced that for more than 20 years, the national level has begun to carry out the census prevention and control of alien species, and during the 14th Five-Year Plan period, the "Key Special Project for Research on Key Biosafety Technologies" was included in the national key research and development plan.
Over the years, a Chinese program to combat the invasion of alien species has been formed in this process. It is understood that at present, the mainland has formed a Chinese program that can effectively respond to biological invasions, that is, Operation 4E. From early warning & prevention (E1, early warning & prevention) and detection and monitoring (E2, early monitoring & rapid detection), to medium-term suppression and interception (E3, early eradication & blocking), to late joint control and mitigation (E4, Entire Mitigation), involving multiple links.
In terms of prevention, "an analysis of the habitat distribution of 200 invasive alien species has been completed. Typical application cases include the Guangdong Red Fire Ant Prevention and Control Command Center System, which can monitor the red fire ant prevention and control area in Guangdong Province. ”
In terms of action monitoring, "more than 700 species (including local species) of molecular detection and intelligent identification technologies have been developed, as well as an intelligent monitoring platform for more than 120 invasive plants." ”
In terms of extinguishing and interception, it includes four links: early eradication and extinction, interception of corridor nodes, ecological barrier barrier, and source control of epidemic areas. "At present, more than 50 invasive organisms have been eliminated and intercepted."
In terms of joint control and disaster reduction, four links, including traditional biological control, ecological alternative restoration, regional joint prevention and control, and cross-border collaborative governance, have also been widely used.
Ragweed, a malignant invasive weed native to North America, is found in most of southern to northeastern mainland China, although it is a grass, its roots are thicker than the thumb. Its biggest problem is that its pollen is very toxic and is very easy to cause allergies in people. According to Wan Fanghao, ragweed pollen allergy patients account for 2%-3% of the total population in ragweed occurrence areas, with more than 14.5 million people suffering from allergies and direct medical expenses of 1.45 billion yuan per year.
"We have an old saying in China that the praying mantis catches the cicada and the yellow finch, and we decided to try to find its natural enemies and use biological control." After strict scientific and administrative procedures, Wan Fanghao's team introduced 7 kinds of ragweed natural enemies from the place of origin, and finally screened out 2 species of ragweed curly moth and broad polyfirefly leaf beetle. The former eats stems and intercepts nutrients, while the latter gathers and eats leaves.
Will these two insects, both alien species, also cause new ecological disasters? Wan Fanghao explained that field tracking experiments had been carried out for many years before the introduction, which confirmed the host specificity of these two natural enemies insects and was highly safe for other native plants.
After the predators entered, the ragweed was quickly defeated. After years of large-scale promotion and application, these two insects have successfully established natural populations in 19 provinces, and have spread from the central release area to the surrounding areas year by year. "In some areas that have been large-scale biocontrol centers, the mortality rate of ragweed plants has reached more than 90%." Wan Fanghao revealed that it will be released in Xinjiang and other places next.
Wan Fanghao believes that on the issue of preventing and controlling the invasion of alien species, it is inseparable from the government's support for the coordination of various departments, the participation of professionals and grassroots personnel in various industries, and the popularization of science education. "We have also found that many invasive alien species are first discovered by volunteers or grassroots farmers, which is a problem of knowledge popularization, and we must first understand it."
Comprehensive census of invasive alien species
In response to the problem of invasive alien species, the Ministry of Agriculture and Rural Affairs and other five ministries and commissions issued the "Work Plan for Further Strengthening the Prevention and Control of Invasive Alien Species" at the beginning of this year, which clearly requires: by 2025, the status of invasive alien species will be basically clarified, the system of laws, regulations and policies will be basically sound, the work pattern of joint prevention and control and group prevention and mass treatment will basically take shape, and the trend of the spread of major invasive species and the risk of invasion will be effectively curbed.
The Beijing News reporter learned that a census of invasive alien species has been launched across the country, which is also the first time to conduct such a large-scale census of invasive alien species.
It is understood that the census work is divided into surveys and key monitoring. The number of invasive alien species nationwide is the primary issue that needs to be clarified in the survey; Priority monitoring is to investigate 164 key invasive alien species.
The census was led by the Ministry of Agriculture and Rural Affairs, with the participation of the General Administration of Natural Resources, Customs, Environmental Protection, Housing and Construction, and Forestry and Grassland. Li Zhihong, professor of the Department of Plant Biosecurity, College of Plant Protection, China Agricultural University, believes that this census will have a more detailed and accurate grasp of the existing invasive alien species species, distribution areas, and harm degrees on the mainland.
In January 2022, the Ministry of Agriculture and Rural Affairs added a new ministry-level key laboratory, namely the Key Laboratory of Plant Quarantine Pest Monitoring, Prevention and Control of the Ministry of Agriculture and Rural Affairs, led by China Agricultural University and jointly established by the Institute of Plant Protection of the Chinese Academy of Agricultural Sciences and Nanjing Agricultural University. The purpose of the construction of the key laboratory is to further strengthen and promote the prevention and control of phytosanitary pests and invasive alien species.
Wan Fanghao told the Beijing News reporter that when the census is over, the newly discovered species will be entered into the database, and the distribution area, development status of these species will be analyzed according to big data, economic losses will be assessed, and invasive species will be selected from them, and prevention and control will be strengthened according to "one policy".
A significant proportion of the invasive alien species identified on the continent have been introduced unintentionally. The insidious nature of invasive alien species highlights the importance of national participation. Wan Fanghao believes that for the general public, it is necessary to strengthen the publicity and study of the "Biosecurity Law", actively fulfill the responsibility of plant quarantine, participate in popular science education, volunteer to participate in prevention activities, and standardize the release behavior.
"Raise awareness, strengthen responsibility, prevent all people, build walls." Wan Fanghao said that it will be a long battle.
Beijing News reporter Li Zhao, editor Yuan Guoli, proofreader Wu Xingfa