WeChat public account "Half Moon Talk" august 4 news, with the increasingly frequent exchanges between countries and regions, alien species are spreading around the world. In recent years, the number of invasive alien species in China has shown an upward trend, and more than 660 invasive alien species have been discovered, becoming one of the countries with the most serious harm from alien species invasion in the world.
Some invasive alien species have become new dominant populations, endangering biodiversity and ecological security, and causing huge economic losses. At the same time, with the new formats of cross-border e-commerce and international express delivery, the intrusion channels are becoming more diversified, and the ecological security risks caused by them have increased significantly.
More than 660 species of organisms have invaded our country
According to the 2019 Bulletin on the State of China's Ecology and Environment released by the Ministry of Ecology and Environment, 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 are included in the List of Invasive Alien Species in China. The survey results of 67 national nature reserves show that 215 invasive alien species have invaded the national nature reserve, of which 48 invasive alien species have been included in the List of Invasive Alien Species in China.
Invasive alien creature "strange fish" found in Beijiang, Guangdong
Invasive alien species in China's agricultural and forestry ecosystems are growing rapidly. From 2008 to 2010, the second national invasive alien species survey conducted by the former Ministry of Environmental Protection showed that there were 488 invasive alien species in China. "This time the data is more than 30% higher than 10 years ago." An industry insider said.
The invasion channels of alien species are more diversified, and in general, they mainly include three categories: natural invasion, unintentional introduction and intentional introduction. Among them, natural invasion is a biological hazard caused by the natural migration of plant seeds, animal larvae, eggs or microorganisms through air currents, winds, water currents or insects and birds.
Dong Jingao, dean of the College of Plant Protection of Hebei Agricultural University, said: "Purple-stemmed zeland, micro-chamomile, American spotted fly, and grassland night moth are all natural invasions of China. The purple-stemmed Zelan grows wildly everywhere, and its seeds drift with the wind and spread everywhere, very easily spreading. It can grow anywhere and is not afraid of floods. ”
No introduction intended. Lu Yongyue, a professor in the Department of Plant Protection at the College of Agronomy at South China Agricultural University, said unintentional introduction may be the most frequent and most frequent invasion route. On the one hand, when carrying out some activities, humans are not aware of the possibility of carrying and introducing alien species; on the other hand, the knowledge acquired in the past is not rich enough to identify potential alien species, which leads to the occurrence of alien species invasion.
Lu Yongyue introduced that among the recorded invasive alien plant pests, except for a few that were naturally introduced from the border, the others were unintentionally introduced.
Intentional introduction. Due to the needs of agriculture, forestry and fishery development, countries around the world often consciously introduce excellent animal, plant and microbial varieties. Dong Jingao said that due to the lack of a comprehensive and comprehensive risk assessment system, countries around the world have introduced a large number of pests, such as water peanuts and Fushou snails, while introducing excellent varieties. These invasive species have altered the living environment and food chain of the original species, flooding in the absence of natural enemies.
In recent years, the invasion of alien species has become more and more extensive in China. Biological invasions occur in many provinces across the country, involving almost all ecosystems such as farmland, forests, waters, wetlands, grasslands, islands, and urban settlements.
Ecological destruction superimposed on biological pollution
Some invasive alien species are harmful because they reproduce rapidly, their numbers increase geometrically, and due to the lack of natural enemy constraints, they often grow into new dominant species in the local area, seriously damaging local biodiversity and ecological security.
According to the Department of Agriculture and Rural Affairs of Guangdong Province, the red fire ant that first appeared in Zhanjiang, Guangdong Province, in 2004, originated in South America, with its heterogeneous diet, strong fertility, fierce habits and strong competitiveness, and it is easy to form a higher density population in newly invaded areas, threatening agricultural and forestry production, human and animal health, ecological environment, social security, etc.
At present, more than 300 counties and districts in China have detected red fire ants, especially in Guangdong, Fujian, Yunnan and Guangxi. From the perspective of natural ecology, red fire ants attack other insects, birds, bird eggs, etc., which is very damaging to the ecology.
Crayfish are considered delicious by many Chinese people, but in Guizhou Weining Caohai National Nature Reserve, the flooding of crayfish has become a disaster. Ran Jingcheng, director of the Guizhou Provincial Wildlife and Forest Plant Management Station, said: "Unexpectedly, crayfish have become a problem in the management of nature reserves."
Crayfish "do not eat vegetarian vegetables if they have meat, and eat mud without vegetables", which is very destructive. In the protected area, crayfish burrow, eat fish and shrimp, aquatic weeds, mud, multiple crayfish together can eat nearly a foot long fish, all kinds of shrimp in the water can not escape the erosion of crayfish, a variety of aquatic weeds have also become food for crayfish. The flooding of crayfish has clearly upset the ecological balance of the sea of grass.
In the Yellow River Delta National Nature Reserve, the erythroceous rice grass has spread more than 60,000 mu, squeezing out the ecological space of local species, reducing the density of benthic animals in the mudflats by 60%, and greatly reducing the foraging and habitat of birds, which seriously threatens the biodiversity of the Yellow River Delta.
Wang Andong, senior engineer of the scientific research center of the reserve, said that the root system of interfluilleine rice grass is developed, which can grow to 50 cm to 100 cm, and the plant grows vigorously and is very thick, gradually encroaching on the alkali canopy of saline land and the habitat of seagrass bed, which is not conducive to the survival and migration of birds.
Dong Jingao said that the area of serious occurrence and harm of invasive insects in forests such as pine wood nematodes, wetland pine mealybugs, and American white moths reaches 1.5 million hectares per year; The area of agricultural infestations such as rice weevils, African large snails, and American spotted diving flies exceeds 1.4 million hectares per year; Ragweed, airplane grass, water hyacinth, rice grass, etc. have spread wantonly, and have reached a situation that is difficult to control.
Invasive alien species also cause serious biological contamination. Dong Jingao said that after the successful invasion of most alien species, growth is difficult to control, causing serious biological pollution and causing irreversible damage to the ecosystem. After invading southern Yunnan, the purple-stemmed Zelan, native to South America, spread to northern Yunnan at a rapid rate, not only unable to grow trees and crops, but also caused asthma in cattle and horses, which brought disaster to livestock production in the invading areas. Worryingly, to this day, people are still helpless against the purple-stemmed Zelan.
"Only part of what was intercepted by customs"
——Import and export trade, cross-border e-commerce caused by the difficulty of control. Chen Aidong, deputy director of the Institute of Environmental Protection of the Yunnan Academy of Agricultural Sciences, said that with the increase in import and export trade in recent years, the risk of alien species invasion brought about by new formats such as international express delivery and cross-border e-commerce has increased significantly, and human carrying and international logistics have become channels for the invasion of alien species.
"The difficulty of control has increased greatly." Chen Aidong said that in the past, there was an invasion of an alien species about every 10 years, and now it may face a new species invasion in two to three years.
A mudflat in Guangxi was invaded by the alien plant Erythroxylum
Lu Yongyue also pointed out that international and regional trade and exchanges are extremely frequent, giving opportunities for the invasion of alien species. At the same time, the source of invasive alien species is complex, involving many countries and regions, as well as a large number of commodities and exchanges, legal and illegal ways, it is difficult to achieve source control and all testing and supervision. "Only a part of the pests in imported goods are intercepted by customs, and the probability of slipping through the net is very high."
--------------------------------------- In the response and management of invasive alien species, "full clarity" and "early detection" are the most important. Regular census of invasive alien species is conducive to the timely discovery of new colonization sites of alien species, and then achieve early detection and rapid response, but the traditional census method of alien species requires the collection of taxonomic experts from different disciplines, and it takes several years to complete a census.
-- The emergency elimination mechanism and response system are not perfect. Chen Aidong said that the current pest invasion includes quarantine pests and non-quarantine pests. For quarantine pests, customs and plant protection plant inspection stations have the responsibility for control and control, and the customs system and talents are relatively complete, but the plant protection plant inspection stations are relatively weak. At the same time, because some organisms have a certain degree of concealment and incubation period, the carrier has diversity and complexity, coupled with the integration of trade, logistics and border ecological integration, prevention and control is more difficult.
"If it is light, it will reduce production by tens of millions of tons, and if it is heavy, there will be no grain to harvest"
The reporter's investigation in Zhejiang, Guangdong, Guangxi, Shandong, Hebei, Guizhou and other places found that invasive alien species seriously threaten the life, health and safety of the masses, bringing huge economic and social risks. Under the background of normalized epidemic prevention and control, invasive alien species and virus-carrying species cannot be ignored when entering through ports, and the purpose of prevention and control should be achieved through targeted special treatment and strengthening of port inspection and quarantine.
Under the epidemic, the importance of food security has been further highlighted. The reporter learned from the interview that the risk of invasion of alien species exists for a long time, such as grassland moths, desert locusts, etc., which affect food security and need to be paid attention to.
In April this year, Qingdao Customs intercepted the quarantine pest of wheat dwarf muscular fungus from imported Lithuanian wheat, which was the second time that China intercepted the fungus from Lithuanian wheat, and it was also the second time that Qingdao Customs District intercepted the germ from imported wheat after 15 years.
According to Su Maowen of the Animal and Plant Quarantine Department of Qingdao Customs, wheat dwarf smut disease has been listed as an important quarantine disease by more than 40 countries in the world, which is harmful to wheat, has high costs of prevention and control, and is extremely difficult to eradicate. China has not yet had this disease, once the wheat dwarf mussel disease bacteria into China and spread with imported wheat, will have a serious impact on China's wheat production, light production of tens of millions of tons, heavy grain can not be harvested, serious threat to China's food security.
The grassland moth that invaded China in 2019 has spread to nearly 1,500 administrative counties and districts in 25 provinces across the country, and the area of more than 15 million mu occurred in the country last year. In Guangdong, the harm plant rate of corn plots in some areas exceeds 60%, and the damage plant rate of corn plots that are not sprayed in time or not in place is even 100%, almost no harvest, and also endanger crops such as sugarcane, peanuts and bananas.
Grassland nocturnal moth larvae and adults Guo Cheng/Photo
Wang Huasheng, deputy director of Guangxi Plant Protection Station, said that since the Tenth Five-Year Plan, the state has invested in the construction of more than 1,000 regional monitoring stations to undertake a type of disease and insect epidemic monitoring task, but some monitoring stations are difficult to complete the tasks of forecasting and prevention and control guidance due to insufficient funds. The prevention of diseases and insect pests of invasive alien plants is related to national food security and the quality and safety of agricultural products, and it is recommended to increase public financial support, and include subsidies for disease and pest monitoring in the financial annual budget to ensure that all localities complete the monitoring and prevention tasks.
Fushou snail, which is common in southern China, can cause rice yields to be reduced by 7% to 15%, and in severe cases, it can be reduced by 50%, and even harvests are cancelled. Once a large-scale outbreak occurs, it will pose a serious threat to rice production and food security.
Some exotic fish entering the farmed waters not only increase feed consumption, but also reduce fishery output. Some predatory exotic fish, such as alligator eels, will cause harvests in farmed waters.
It is especially important to be vigilant against pathogenic pests
In the context of normalized epidemic prevention and control, it is more necessary to pay attention to foreign pathogenic pests.
On March 16 this year, Tianjin Customs detected quarantine pest ragweed in a batch of 78.93 tons of oat seeds imported from the United States. This is the first time ragweed has been detected in oat seeds at ports across the country.
Ragweed was included in the list of the first invasive alien species in China in 2003, which not only destroys the ecology, but also endangers human health. Recently, ragweed was found in Taiping Mountain and Qingdao Botanical Garden in Qingdao, Shandong. Liu Jie, deputy chief physician of the Department of Otorhinolaryngology of Qingdao Shinan District People's Hospital, said that ragweed is widely spread, endangering agriculture, ecology and human health, and its pollen has become one of the important causes of allergic rhinitis and asthma in China.
In addition to plants, some insects also endanger human health. In the insect behavior laboratory of the Zhejiang Academy of Agricultural Sciences, the reporter saw several ant nests as observation objects. In an observation box only half a square meter in size, dense red fire ants drilled in and out of the soil, and the soil was eroded into holes. "Don't look at such a small nest, there are at least tens of thousands of red fire ants in it." Dr. Lu Yaobin, director of the Institute of Plant Protection and Microbiology of Zhejiang Academy of Agricultural Sciences, said.
Lu Yaobin told reporters that red fire ants not only affect agricultural production, but also affect human health. Red fire ant nest and ordinary ants are not the same, shaped like sandbags, people do not pay attention to stepping on it, red fire ants will immediately gush out like a tide of stinging attack, people with allergies are stung, will produce severe burning pain, followed by redness, high fever, severe shock and death.
There are many parasites of Fushou snail, which is an intermediate host for the curling spiny mouth fluke and the Guangzhou tube roundworm, which poses a greater threat to human health. Ma Yongbing, deputy director of the aquatic products station of the Guiyang Municipal Bureau of Agriculture and Rural Affairs and senior aquatic engineer, said that every year from April to May is the breeding period of Fushou snails, and the young eggs of Fushou snails are bright pink, which is curious, but in order to avoid parasitic infection, it is recommended not to touch.
Inspection and quarantine personnel explain to villagers the harm of foreign pest Fushou snail Song Weiwei /photo
Liu Yusheng, deputy dean of the College of Plant Protection of Shandong Agricultural University, said that in view of invasive alien species with strong vitality and great harm, it is necessary to establish a normalization mechanism, study their growth laws and natural enemies like local pests, and be prepared to fight a protracted war and curb the occurrence of disasters.
Build a dam and guard the gate of the country
In view of the rapid spread, wide distribution and great influence of invasive alien species, it is necessary to improve legislation, strengthen supervision, guard the country's door, and effectively prevent it.
-- Improving legislation. Dong Jingao, dean of the College of Plant Protection of Hebei Agricultural University, and Lu Yongyue, professor of the Department of Plant Protection of the College of Agronomy of South China Agricultural University, said that at present, China still lacks systematic and targeted laws and regulations to prevent the invasion of alien species. The existing Laws of the People's Republic of China on the Quarantine of Animals and Plants Entering and Leaving the Country, the Forestry Law of the People's Republic of China, the Agricultural Law of the People's Republic of China and other laws, although they involve the prevention and control of invasive alien species, mainly focus on import quarantine and introduction, and lack a unified system. It is recommended to improve the institutional system, promote the legislative work of the Biosecurity Law, and promote the formation of a regulatory synergy.
-- Popularizing prevention and control methods. The interviewed experts and grass-roots cadres believe that the prevention and control methods that have proved effective in practice can be summarized and promoted in a timely manner, and targeted special treatment of invasive species can be carried out.
For the management of red fire ants, the Institute of Plant Protection and Microbiology of Zhejiang Academy of Agricultural Sciences provides experience. "How to spot red fire ants is the key. We developed traps according to the life rules of the red fire ant, and inserted the bait, and the red fire ant was easily found. Lu Yaobin said, "After discovery, the two-stage control method is generally adopted." The first stage is to release the poisonous bait, and after the red fire ant moves the poisonous bait back to the nest to share, the whole nest of red fire ants may gradually die. In the second stage, after half a month, we will monitor again, and if we find that there are still red fire ants, we will inject liquid pesticides to achieve the purpose of complete elimination. ”
Ran Jingcheng, director of the Guizhou Wildlife and Forest Plant Management Station, told reporters that the control methods of Fushou snail include physical control, agricultural control, and biological control. "Physical control is to destroy the spawning site of Fushou snails by digging up aquatic weeds and eradicating weeds in the field, while manually picking up and eliminating snails, as well as removing Fushou snail egg blocks. Agricultural control is done by flood irrigation, so that the egg blocks are submerged in water during the incubation period. Juvenile Snail is the food of ducks, which can be raised in rice paddies to achieve the purpose of biological control. ”
-- Strengthening quarantine inspection and law enforcement at ports. Animal and plant quarantine departments at customs ports are the first line of defense to effectively block biological invasions. It is recommended to continue to increase the intensity of quarantine inspection at ports and strengthen the allocation of inspection facilities and equipment and animal and plant quarantine professionals. Tao Dayun, director of the International Department of the Yunnan Academy of Agricultural Sciences, said that agriculture, forestry and grassland, customs, ecological environment and other departments should work closely together to effectively pay equal attention to foreign and domestic quarantine, establish a unified coordination and management agency, follow up and monitor for a long time, and formulate strategies to prevent new biological invasion events.
-- Strengthening international cooperation. Biological invasion is a common problem facing the world, and China has participated in and implemented international conventions such as the Convention on Biological Diversity and the Convention on International Trade in Endangered Species of Wild Fauna and Flora. It is advisable to continue to strengthen international cooperation, share resources and jointly seek solutions. Use the international biological invasion database to explore the law of biological invasion in China and establish a database of biological species that pose a threat to China.
(Originally titled "More than 660 Species Have Invaded China!") Invasive alien species increase by 30% in ten years")
Source: WeChat public account "Half Moon Talk"