Beijing News (reporter Li Yukun) In daily life, we will come into contact with many creatures, such as the fragrant bullfrogs and crayfish on the table, the flowers and plants swaying in the park, the annoying cockroaches in the buildings... Have you ever thought that they could be invasive species?
Recently, a plant called Japanese knotweed has spread wildly in the UK, and the news of serious damage to the building has aroused heated discussion among netizens. Some netizens recalled the suspected invasive species they had encountered in China and expressed concern about China's monitoring of invasive species. On May 21, Yunnan released the List of Invasive Alien Species in Yunnan Province (2019 Edition) (hereinafter referred to as the "List"), which is the first provincial invasive alien species list in China. The "List" includes 441 species and 4 varieties of invasive alien species such as Fushou snail and American cockroach found in Yunnan, of which 50.1% of the origin is from the Americas.
In recent years, China is facing a severe situation of biological invasion, and customs often seize invasive species during inspections. One of the key tasks of the Ministry of Agriculture and Rural Affairs this year is to promote the legislation on the management of alien species and propose the second batch of national key management of invasive alien species list.
On May 8, 2013, a large number of invasive plants covered the river surface of the Pearl River on both sides of the Jinshazhou Bridge in Guangzhou. Photo/Visual China
Bullfrogs, crayfish, American cockroaches and other "on the list"
The so-called invasive alien species refer to alien species that have formed self-regenerative ability in local natural or semi-natural ecosystems, and may or have caused obvious damage or adverse effects to the ecological environment, production or life.
The "List" released by Yunnan this time divides invasive species into 5 categories, including grade I malignant invasive species, grade II. severe invasive class, grade III local invasion class, IV. general invasive class, and V. class to be observed.
Sun Hang, director of the Kunming Institute of Botany of the Chinese Academy of Sciences, introduced that the malignant invasion class refers to the invasive organisms whose biological characteristics have been determined to be insignificant and seriously affect the economic and ecological benefits at the provincial level; the serious invasion class refers to the large loss and impact on the economic and ecological benefits at the provincial level; the local invasion class refers to the large-scale harm at the provincial level; the general invasion class refers to the invasive organisms whose biological characteristics have been determined to be less harmful and are difficult to form a new development trend The pending class is a species that has not yet reached the level of invasion, is still in a state of naturalization, or has an unknown understanding and cannot currently determine future trends.
Among them, the grade I malignant invasion class includes micro-chamomile, hyacinth blue (water hyacinth), brown cloud agate snail, small tube Fushou snail and so on. American cockroach (cockroach), protocellfish (crayfish), bullfrog, etc. belong to the class II serious invasion class.
Sun Hang said that the origin of invasive alien species in Yunnan comes from 6 regions, of which the most species from the Americas, there are 223 species and 1 variant, accounting for 50.1% of all invasive species, "the List will provide scientific support for promoting biodiversity monitoring in Yunnan, and will also provide experience and reference for the compilation and research of the list of invasive alien species in other regions of China." ”
It is understood that the current commonly used ways to prevent and control invasive alien species mainly include artificial control, chemical control, etc., artificial control relies on manpower or mechanical equipment for removal, and chemical control is the use of chemical herbicides to prevent and control. In addition, the population density of invasive alien species can be controlled through biological or natural enemy control, the use of pathogenic microorganisms, etc., or through comprehensive management, combined with one-way technology.
China's customs have seized invasive species many times this year
The tricky situation facing Yunnan is a microcosm of china's biological invasion situation. China is one of the countries most affected by alien invasions, and customs regularly seize invasive species during inspections, with many cases occurring this year alone.
In March this year, when the customs officers of Guangzhou Baiyun Airport under Guangzhou Customs inspected the inbound baggage carried by an African student, they found two live African snails in his bag. The African giant snail is known as the "pastoral killer", and the person concerned said that he wanted to declare customs as a pet.
In April this year, when inspectors at the Qianjiang Customs Post Office under Hangzhou Customs conducted routine inspections of incoming mail, they found an abnormality in a piece of mail from Spain. After opening the box, it was found that there were 8 small boxes containing more than 200 live rat women.
Around the same time, Chengdu Customs seized 8 live scorpions. This batch of scorpions came from the United Kingdom's undeclared product name entry mail, the image was abnormal when passing the X-ray machine, and when it was opened, it was found that there was a scorpion in each of the 8 storage boxes. After testing and identification, it belongs to the South African flat stone scorpion, native to South Africa, with weak toxicity, gentle temperament and slightly neuroticism.
On August 24, 2017, in Berlin, Germany, the invasive species of Protocrayfish (commonly known as "crayfish") appeared in the Tuelgarten Park. Photo/Visual China
"If 'foodies' could solve everything, there would be no biological invasion."
In recent years, Asian carp have been breeding wildly in the United States, threatening the local ecological balance. However, as a material for Chinese cooking, carp is deeply loved by the Chinese people. After learning of the flood of carp in the United States, many netizens said, "Let domestic foodies solve it." Coincidentally, the alien crayfish, a species that invaded China, is also a delicacy on the Chinese table. This has led many netizens to believe that the main reason why invasive species are flooded is that they have not developed a way to eat.
This view is clearly biased. Liao Wanjin, a professor at the School of Life Sciences of Beijing Normal University, told the Beijing News that if "foodies" can solve all problems, there will be no biological invasion.
Liao Wanjin said invasive species are only a tiny fraction of alien species. The reporter consulted the Database of Alien Species in China and found that there are 754 invasive species in China. Among them, invasive plant species are the most numerous, 1.4 times and 4.4 times that of invasive animals and microorganisms, respectively. From the source point of view, invasive plants are mainly from North and South America, invasive animals are mainly from Asia, and invasive microorganisms are mainly from North America.
Not long ago, a creature called Japanese knotweed invaded the United Kingdom and caused a local ecological crisis, which triggered heated discussion among netizens, who were worried that this terrible species would also invade China.
Liao Wanjin introduced that Japanese knotweed is a variant, introduced to Britain in the 19th century, molecular markers reveal that the British Japanese knotweed is a large clone, mainly relying on clone growth, basically no genetic variation. This variant crosses with another species of the same genus to produce a hybrid that has some genetic variation.
"Does China have Japanese knotweed?" The English version of flora of China says there is no such species, but in the published paper, researchers at the Wuhan Botanical Garden and Guizhou Normal University believe that Japanese knotweed is distributed in southern China, and this species is an indigenous Species in China. Liao Wanjin said that the genus where knotweed is located is called "Shou Wu genus", and the invasive species do not cause harm in the place of origin mainly because of natural enemies.
background
Multi-sectoral release of a list of multiple invasive species this year will push for legislation
China's relevant departments have always been vigilant against biological invasions, and many departments have issued a list of invasive species.
The list of invasive alien species jointly released by the former State Environmental Protection Administration (and later the former Ministry of Environmental Protection) and the Chinese Academy of Sciences has been published in four batches. In January 2003, the former State Environmental Protection Administration and the Chinese Academy of Sciences jointly released the first list of alien invasions, a total of 16 species, typical species such as hyacinth (water hyacinth); in January 2010, the former Ministry of Environmental Protection and the Chinese Academy of Sciences jointly formulated, the Ministry of Environmental Protection issued the second batch of alien invasion list, a total of 19 species, the more famous such as the original crawfish (crayfish); in August 2014, the General Office of the Ministry of Environmental Protection released the list of the third batch of alien invasions. There are 18 species, such as the Common Brazilian Turtle, and in December 2016, the General Office of the Ministry of Environmental Protection released the fourth list of alien invasions, with a total of 18 species.
In 2007, the former Ministry of Agriculture and the former General Administration of Quality Supervision, Inspection and Quarantine issued a list of quarantine pests entering China, which is divided into 435 species in six categories. In 2017, the list was updated with the addition of 6 new quarantine pests, including fuso sheep mealybug, cassava powdery mealybug, sunflower black stem disease, and allogeneic amaranth weeds, and the new list included 441 species of insects, molluscs, fungi, prokaryotes, nematodes and weeds. In addition, China also has a list of animals and plants and their products and other quarantine items that are prohibited from being carried or mailed into the country, and live animals other than cats and dogs are prohibited. In 2013, the former Ministry of Agriculture published a list of 52 invasive alien species under national key management.
It is worth mentioning that the "2019 Key Points for agricultural and Rural Science and Education Environmental Energy Work" issued by the Ministry of Agriculture and Rural Affairs this year proposes to promote the legislation on the management of alien species and put forward the second batch of national key management of invasive alien species list.
Inventory
Those invasive species common in our country
1. Invasive species climbing onto the table
Protocellum crawfish, bullfrog, African giant snail
bullfrog. Photo/Visual China
Some species that invaded China have become a delicacy on the table, typical of which are protocell shrimp, bullfrogs, African snails and so on.
The original crawfish is the famous freshwater crayfish in Guijie Street, native to North America, entered China in the 1930s, the edible value was excavated in the 1960s, the breeding fever continued to rise, the introduction of species in disorder everywhere, and the large-scale spread from the 80s to the 90s of the last century. Protocellfish can endanger indigenous species by snatching up survival resources, preying on native flora and fauna, and carrying and transmitting pathogenic sources.
Bullfrog, also known as the American frog, is native to the eastern part of the Rocky Mountains of North America and was widely introduced around the world because of its edibleness, and was introduced to China in 1959. Bullfrogs are highly adaptable, have a wide range of diets, have fewer natural enemies, have a long lifespan, have strong reproductive ability, have obvious competitive advantages, and are easy to invade and spread.
The African giant snail is also the dish of some people, alias French snail, native to the east coast of Tanzania, Zanzibar, Pemba Island, Madagascar around the island. At present, it has spread to Guangdong, Hong Kong, Hainan, Guangxi, Yunnan and other places in China. Its eggs and larvae can be spread with ornamental plants, wood, vehicles, packaging boxes, etc., and the egg stage can be mixed into the soil for transmission. They bite off the young shoots, shoots, young leaves and stem skins of various crops and have become pests that harm crops, vegetables and ecosystems.
2. Invasive species introduced by mistake due to greening and other reasons
Hyacinth, lantana, a Canadian yellow flower
A yellow flower in Canada. Photo: Chinese Plant Image Library
The first invasive species many people hear about is the water hyacinth mentioned in textbooks, scientifically known as the hyacinth. Yunnan Dianchi Lake was once heavily polluted, and the local government believed that large-scale cultivation of water hyacinth was the best way to control Dianchi Lake. However, water hyacinths multiply too quickly, causing new pollution.
It is native to northeastern Brazil and is now found in warmer regions of the world. In China, it is mainly distributed in 19 provinces (autonomous regions and municipalities directly under the central government) in southern Liaoning, north China, east China, central China and south China, and it grows as weeds in the Yangtze River Basin and the southern regions.
Lantana is a beautiful flower, also known as the five-colored plum, which is often cultivated as a flowering shrub. Lantana is native to tropical America and has become a global pantropical pest. At the end of the Ming Dynasty, it was introduced to Taiwan by the Spaniards, and because the flowers were more beautiful, they were widely cultivated and introduced, and then fled. Lantana often forms dense monooptimal communities, which seriously hinders and crowds out the survival of other plants, and is a vicious competitor to pastures, forest farms, tea gardens and orange groves in southern China.
A yellow flower in Canada, also known as Milan, happiness flower, people who often arrange flowers may not be strangers. Native to North America, the Canadian yellow flower is cultivated and naturalized in temperate zones in the Northern Hemisphere. It was introduced to China in 1935 as an ornamental plant, and spread into a weed in the 1980s. It often invades urban gardens, suburbs, wastelands, riverbank highways and railway lines, and also invades low-mountain and sparsely forested wetland ecosystems, seriously depleting soil fertility; long flowering periods and large amounts of pollen can lead to pollen allergies.
3. The most disgusting invasive species
German cockroach, American cockroach
German cockroach. Image source: List of invasive alien species in China (third and fourth batches)
If most invasive species survive in the wild and therefore fail to attract enough attention from humans, there is one invasive species that is deeply repugnant and causes "extreme discomfort", and its name is the German cockroach, that is, the cockroach. They are extremely fertile, breeding 5-6 generations a year.
The German cockroach is native to South Asia, and some scholars believe that it originated in Africa. It spreads over long distances with inter-regional economic trade. At present, it is distributed all over the world, and China is now mainly distributed in Beijing, Liaoning, Heilongjiang, Shanghai, Fujian, Guangdong, Guangxi and other places. German cockroach secretions can spoil food, causing human poisoning. It will bite and destroy food, paper, cultural relics, electronic equipment, etc., while carrying a variety of pathogenic bacteria such as dysentery bacteria, tuberculosis bacteria and other pathogenic bacteria and threatening human health.
The German cockroach also has a distant relative of the same purpose that has also become a flood of invasive species in China, the American cockroach. Also known as cockroaches, the American cockroach has a more terrifying characteristic, and when there are no males, females can reproduce asexually.
Native to northern Africa, the American cockroach may have been brought into the Americas from Africa during the period of black trafficking. At present, it is widely distributed in various provinces and cities in China. The excrement and degeneration of the American cockroach have allergens on the epidermis, which can cause rashes, asthma and other diseases; the American cockroach can also carry a variety of pathogenic bacteria, such as dysentery, pseudomonas aeruginosa, Proteus, etc., which is an important vector for many infectious diseases of livestock and humans.
4. Invasive species that are often mistakenly released
Brazilian tortoise, "scavenger" fish
Brazilian tortoise. Image source: List of invasive alien species in China (third and fourth batches)
In recent years, in order to restore the ecology, the relevant departments have often organized releases. However, some "flooded with love" people do not distinguish between species, release at will, and have also become the reason for the proliferation of some exotic species, such as the Brazilian turtle.
Native to the south-central United States, along the Mississippi River to the area around the Gulf of Mexico, the Brazilian turtle has been found to have wild individuals on all continents except Antarctica, and has successfully invaded Europe, Africa, Australia and other areas.
In the 1980s, Brazilian turtles were introduced to the mainland via Hong Kong and then quickly flowed throughout the country. Pet discarding, breeding escape, wrong release, etc. have led to its widespread presence in the wild, and China has become the country with the largest number of Brazilian turtles in the world. The Brazilian tortoise crowds out native species, posing a serious threat to native turtles in invasive areas and is also the main culprit in the spread of Salmonella.
Another invasive species that is often mistakenly released is the "scavenger", scientific name leopard print lipid catfish. Scavengers are also called spoonbills, garbage fish, people who like to raise fish are not unfamiliar with this fish, generally put two in the fish tank, clean up the bottom of the garbage and the tank wall moss.
Scavengers are native to South America and are widely distributed in the Amazon River Basin. In 1980, scavengers were introduced to China as ornamental fish. Because adult scavengers eat a large amount of food, in addition to moss and other algae, they will also feed on the eggs of other fish and will also swallow fry. This fish has no natural enemies in the country, is extremely easy to survive, and breeds in large quantities, which seriously occupies the living space of native fish.
Beijing News reporter Li Yukun Editor Zhang Chang Proofreader Lu Aiying