What would the ideal, or future, Dianchi Lake water body look like?
On January 20, General Secretary Xi Jinping, who was inspecting in Yunnan, came to the ecological wetland of the Xinghai Peninsula of Dianchi Lake to inspect the protection and governance of Dianchi Lake. A glass "ecological tank" at the scene is eye-catching: snow white and elegant sea cauliflower blooms on the water, Dianchi Lake golden thread catfish swim through, and the toothless mussels in the back corner inhabit the bottom of the tank. Li Weiwei, deputy director of the Kunming Zoological Museum of the Chinese Academy of Sciences, who is responsible for the layout of the ecological tank, introduced: "Sea cauliflower, golden thread catfish and toothless mussels represent the indigenous plants, fish and snail mussels of Dianchi Lake, respectively, and this miniature version of the ecosystem is the ideal state that the waters of Dianchi Lake are expected to achieve in the future." ”
She continued: "The protection and governance of Dianchi Lake has entered a new window period, and has also ushered in a period of opportunities for scientific and technological innovation. Gradually shifting from engineering governance to more and more indigenous species will return and reappear, and the biodiversity of Dianchi Lake will be richer, forming a three-dimensional and balanced ecosystem. ”
The golden mackerel that shines in the sun is known as the "Dianchi Antique": it survived more than three million years ago when Dianchi Lake was formed, but with the destruction of the living environment, it disappeared from the lake in the 1980s; with the breakthrough of artificial breeding technology and the continuation of breeding and stocking activities, it has now reappeared in the upper reaches of the Panlong River in the Yunnan River. The fate of a fish is so closely related to Dianchi Lake, which enlightens the current lake governance and restoration.
From endangered national grade II protected animals to today's tens of millions of artificial breeding capabilities; from rare extremely small populations in the wild to mountain breeding species; from exiting the lake to issuing a warning to humans, to re-entering the lake to biological treatment of the water body of Dianchi Lake - what kind of "rise and fall" has the Dianchi golden ray catfish, which ranks first among the "four famous fishes in Yunnan", experienced?
The Mystery of Disappearance: Dianchi Lake's "Early Warning" to People
The babbling water is crystal clear, and the Yunnan light-lipped fish, Kunming split-bellied fish, Yunnan pan-catfish and Dianchi lake golden-threaded catfish wander in groups with their heads and tails. Clusters of sea cauliflower float along the water, and the flowers dot the water. In the late spring, the reporter came to Kunming Songming Black Dragon Pond, as if mistakenly entering the peach blossom source, saw the long-lost sea cauliflower and wild fish, and felt comfortable.
Pan Xiaofu, a teacher from the Kunming Institute of Zoology of the Chinese Academy of Sciences, "a word urges people in deep dreams": "Think about it, in the past, five hundred miles of Dianchi Lake, all the rivers into Dianchi Lake, were like this!" ”
When this kind of Dianchi Lake comes to the bottom of the eye, how should it be "happy and empty"? But it's all there! Pollution in Dianchi Lake peaked at the turn of the century, and people saw the "green paint" dianchi lake water after the cyanobacteria outbreak, and the foul smell was avoided. As the poet laments: Have you really had those — lake blue, turquoise blue, azure blue, deep blue, peacock blue? Many of the customs of Dianchi Lake that were once there have also been left in the literature or memory. If nothing else, the Dianchi golden thread catfish is an example.
Dianchi lake golden-threaded catfish, commonly known as goldfish and small holefish, was once the "flagship species" of Dianchi Lake. Adult fish like to eat small fish and shrimp, and are the first of the "four famous fish in Yunnan" - the other three are Dali bowfish in the Erhai Sea, the white fish in Fuxian Lake and the big head carp in Xingyun Lake, which can be described as a famous fish in the plateau.
But the golden line catfish disappeared in the Lake of Dianchi Lake in the 1980s, what is the reason?
Yang Junxing, a researcher at the Kunming Institute of Zoology of the Chinese Academy of Sciences, has been dealing with fish for 37 years. He explained: "The reasons are comprehensive, the main reasons are the survival, the great changes in the spawning environment, and the competition is not as good as alien species, and indiscriminate fishing and water pollution are also the reasons." ”
Dianchi lake golden thread catfish is a "delicate" fish. Every year from December to March, it will swim to the springs around Dianchi Lake and the underground dark river to lay eggs, the water temperature is 18-20 degrees, it must be clean water. It carefully lays eggs to the surface of underwater gravel and enters a 7-8 day incubation period, while the incubation period of "four big fish" such as green, grass, silver carp and bighead carp is only two or three days. This means that if there is no spawning environment such as Longtan and Underground River, or if the spawning migration channel is blocked, the Dianchi Lake golden line catfish will suffer a fatal blow. In the last century, Dianchi Lake was large-scale around the lake for farming, the construction of breakwaters and other projects, many longtan were masonry into ponds for irrigation, water, coupled with the shrinkage and pollution of the river into the Dianchi River, the golden line catfish had to "flee" from dianchi lake, "remnants" in some surrounding longtan.
According to historical records, the construction of land around the lake in Dianchi Lake began at the end of 1969, and at least 100,000 people dumped stones and dirt into Dianchi Lake every day, and after three major "battles" of embankment, drainage and soil filling, which lasted for 8 months, the "Dam Bridge Smoke Willow", one of the eight scenic spots in Kunming, became black humus. In the end, the area of land reclamation around the lake was 30,000 mu. However, many years later, the utilization rate of newly built land is only 40%, and "a bag of bad rain can burn in dry weather." From 1971 to 1982, the cumulative grain production was 4.07 million kilograms, less than a quarter of the grain used by the field-making army that year. At that time, the landmaking of the battlefield had its special historical background and considerations, but the ecological price paid was irreparable.
For a long time, Dianchi Lake has also been a production-oriented lake, and the task of increasing the output of aquatic products to "solve the stomach problem" is huge. Before 1957, the fish in Dianchi Lake were mainly native fish. In the late 1960s, silver carp and grass carp stocked in Dianchi Lake became the mainstream, and in 1969 the catch of aquatic products was 3080 tons. Since 1973, Giant river prawns and white shrimp have been the main catches in Dianchi Lake, and aquatic production increased to 8 363 tonnes in 1975. In the 1980s, the exotic species of silverfish began to become the main product, and the production of this alone reached 3500 tons.
Wang Yong, deputy director of the Fishery Administration Supervision and Administration Department of Dianchi Lake, joined the work in 1988 and has been dealing with fisheries ever since. He said that it was not until 2010 that native fish species, that is, artificially bred Dianchi golden ray catfish, were released into Dianchi Lake from the perspective of water treatment. The introduction of the "Four Big Fish" rich vegetable basket, especially the accompanying wheat ear fish, anchovies, etc., has made the golden thread catfish unbearable - the elemius will eat its fertilized eggs laid on the gravel.
Yang Junxing said: "The 'fragile and delicate' breeding of indigenous fish such as the golden thread catfish just shows that they have a high degree of dependence on the healthy water environment of Dianchi Lake, and the general secretary said that the landscape, forest, field and lake grass is a living system, and this system is interlocked, and it is impossible to lack that chain." He believes that the withdrawal of the Dianchi lake is actually an early warning to humans that Dianchi lake has been "sick", but this warning was not taken seriously at that time, or it was not understood.
Dianchi Lake disappeared not only the golden thread catfish. In the 1960s, there were 26 species of indigenous fish in Dianchi Lake, and now only 4 species exist in the lake. At present, there are 15 endangered or vulnerable species of indigenous fish species in Dianchi Lake, and 8 species are listed on the IUCN Red List of Threatened Species.
There are more than 70 species in the genus Goldenrod, which is a species-rich family in the carp family. If there is a Dianchi Lake golden line catfish, there are also Fuxian golden line catfish in Fuxian Lake and Yangzong Haiyang Zong golden line catfish – standing on the top of Kunming Liangwang Mountain, you can enjoy a panoramic view of the Three Lakes. So how much impact does a species of goldenrod have even if it goes extinct?
Cave creatures are one of the most mysterious biological groups on Earth and are an excellent material for studying the survival and adaptation of organisms in extreme environments. Yang Junxing introduced: "Every creature is a 'heavenly book', containing hidden geological knowledge and evolutionary information, a species disappears, and a page in the book is torn off." ”
Dr. Wang Xiaoai, who also works at the Kunming Institute of Zoology of the Chinese Academy of Sciences, understands biodiversity from the perspective of genetic diversity, she said: "There is genetic diversity only when there is diversity of species, and the rich genes brought by it are the resource bank for human beings to cope with various uncertain changes, such as responding to various epidemic infectious diseases, etc. Also need to use genetic research. ”
The work of breeding: "Seize the last chance that God has left us"
One day in 2003, Yang Junxing received a strange transoceanic phone call.
The other party claimed to be from the Global Environment Facility (GEF), planned to fund his research on the restoration of aquatic biodiversity in Dianchi Lake, and expressed his willingness to provide $980,000 in scientific research funding. Yang Junxing's first reaction: "It's not a scam call, what do you get back for so much money?" ”
The call came from Tony Victor, biodiversity officer for east Asia and the Pacific at the Global Environment Facility, and the money was distributed by the World Bank as a grant — Yang Junxing's team had previously completed the artificial breeding of the trout in Fuxian Lake, which attracted the attention of GEF. With this money, Yang Junxing turned his eyes to the Dianchi golden thread catfish, which he had long been "begging for".
In 2004, the Kunming Institute of Animals of the Chinese Academy of Sciences established a rare fish breeding base in Dabanqiao, Kunming, about 23 acres. Pan Xiaofu recalled that from the unit to take the No. 74 bus for more than an hour, then turn to the No. 11 bus, go to Dabanqiao, and then change the "motorcycle" to spend five yuan to get to the base, and the base is surrounded by contiguous farmland.
With funding and a base, Yang Junxing's team began to look for fish in the wild. They traveled through the dragon ponds and streams scattered around Dianchi Lake, and eventually found small populations of wild golden herring in Songming Black Dragon Pond and Muyang River. Recalling in the office now, Yang Junxing said: "This may be the last chance that God left us to save the Dianchi Golden Thread Catfish, and without the support of the Chinese Academy of Sciences, the Yunnan Provincial Development and Reform Commission, the Environmental Protection Department and the Science and Technology Department, we would not be where we are today." ”
Dianchi lake goldenrod survives well in the wild, but when it comes to the laboratory, it does not breed, and the sperm and eggs of the goldfish in the pond are always immature, cannot be artificially inseminated, and some fish do not even excrete sperm.
The researchers began to analyze the conditions required for the breeding of the Dianchi lake golden-threaded catfish: what to eat to help them mature sexually, so that the bait recipe highly fits their "wild recipe"; the temperature, water flow, light conditions required for natural breeding in the wild, and then artificially creating an spawning environment...
Cold and summer, Yang Junxing's team has walked around the Dianchi Lake golden line catfish for more than three years. Yang Junxing said: "Fish can't speak, and during the breeding period, they are used to hiding, and they can only rely on a little observation to accumulate." ”
Pan Xiaofu has been stationed since the establishment of the base, and the Dianchi golden line bream is active at night, and they sleep on the fish pond during the breeding period. "Engaging in scientific research will not be able to fish on people", Pan Xiaofu recalled: "Observing fish at night is tired, turning over and seeing the sky full of stars, it is also fun." In those sleepless nights, Pan Xiaofu named his newborn son Haoming: I hope to remember this pen in the vast Dianchi Lake.
Sprouts! In 2007, the laboratory finally produced more than 300 fry. After Yang Junxing's team explored the sexual maturity law of golden thread catfish, its fertilization rate increased from more than 30% in one hour to 70% within half an hour. Since then, the embryonic development of dianchi golden ray catfish, the transformation and growth of feeding habits of juvenile fish, the fertility of fish, and the relationship between egg diameter size and embryo survival have also been clarified one by one.
In mid-March, the reporter came to the fish base in Dabanqiao. The bucket shifted from star to star, an airport highway shortened the journey a lot, and new houses for relocated households with reservoirs were built around the base, and the Shanghai-Kunming high-speed rail flying frame was in front of them. In the hatchery, in the steel basin with a diameter of two or three meters, you can see the juvenile fish of the Dianchi Lake golden-threaded catfish. The young Dr. Zhang Yuanwei pointed to the fertilized eggs and said, "The fish eggs are stuck to the attachment, and from the initial breeding of three hundred to tens of millions of them now, the species of the golden thread catfish has been preserved!" ”
There are four levels of preservation of a species: population preservation, individual preservation, cell preservation, and molecular preservation. Wang Xiao'ai, a self-proclaimed "cell keeper" - "freezes" the cells of Dianchi golden herring in liquid nitrogen at minus 196 degrees Celsius, and then restores its activity when needed. In addition to the Dianchi lake golden ray catfish, she also gave more than 30 kinds of Yunnan indigenous fish "file card" to achieve cellular level preservation. Wang Xiaoai is also a doctor of Teacher Yang Junxing, and Zhang Yuanwei is her classmate and husband. From the older generation of scientists, the younger ones read the feelings and responsibilities. Zhang Yuanwei mastered the hybridization technology of Dianchi golden thread catfish and carp, which is very conducive to the promotion of industrialization, which means patents and money. Now instead of Pan Xiaofu in the base, he said that he would not do it here just to figure out money.
It should be noted that in the south of Caiyun, known as the "biological kingdom", there are 629 species of freshwater fish, of which 594 are indigenous species, accounting for about 40% of the country's freshwater fish, ranking first in the country, while there are currently 138 species of indigenous fish in Yunnan that are extinct, critically endangered, endangered and vulnerable. From these figures, it is not difficult to understand the special significance of Yang Junxing's team work. Teacher Yang said, "Protecting biodiversity has global value, my hair is gray, but there are still many endangered fish waiting for us." ”
Out of the laboratory, the Dianchi lake golden thread catfish will face two directions: release into the water body of Dianchi Lake, return to the ancestral world, purify the water body of Dianchi Lake; sustainable development and utilization of artificial breeding, "swim" back to the public table, and improve the well-being of the people. Since 2010, the water body of Dianchi Lake has released golden line catfish for the first time, which is the artificial breeding of fish fry by Yang Junxing's team. Ten years later, how are they doing?
Ecological governance: biodiversity restoration requires "embroidery effort"
In the spring season, a piece of news is particularly interesting: 36 pincer-billed storks appear in the Dianchi Wetland. Painted ibises, listed on the IUCN Red List of Threatened Species, have also reappeared in Dianchi Lake. The wild birds recorded around Dianchi Lake are constantly refreshed, including 10 or 20 species of stone sandpipers, iron-billed sandpling sandpipers, three-toed sandpipers, and white-winged floating gulls. In recent years, the wetland restored by Dianchi Lake has become a natural "bird's nest". After more than 10 years of restoration, dianchi lakeshore has formed an ecological belt with a width of about 200 meters, an area of about 33.3 square kilometers, and 80% vegetation coverage, and a "green dragon" protects Dianchi Lake.
Since the "Ninth Five-Year Plan" has been included in the national key river basin water pollution prevention and control, Dianchi Lake governance is a major event related to the overall situation of Yunnan and the key project of ecological civilization construction, Yunnan Province, Kunming City fully implement the "six major projects", one session after another. In 2016, the water quality of the whole lake rose from inferior class V. to class V., the first to pick the "inferior class V. hat"; in 2018, it rose to class IV., the best in 30 years; in 2019, the water quality of the whole lake of Dianchi Lake continued to remain in class IV. With perseverance for more than 20 years, the treatment of Dianchi Lake has achieved remarkable results, and it has also changed from a single pollution control to "equal emphasis on pollution control and ecological restoration".
Pan Min of the Dianchi Plateau Lake Research Institute spoke highly of the achievements of the Dianchi Lake Treatment of the Lake interception and "four retreats and three returns" in that year, of which "four retreats and three returns" refers to the realization of returning lakes, forests, and wetlands through the withdrawal of ponds, fields, people, and check-outs. "People retreating into the lake and recuperating are the 'production beds' of the biodiversity of Dianchi Lake," she said: "Through engineering measures, we will first solve the problem of external pollution, and then turn to the ecological governance of lake water, which is also a common experience of international lake governance." ”
In a biologically balanced and ecologically healthy lake, there should be no "one fish alone". Since 2010, more than 1.8 million gold-lined catfish have been released into Dianchi Lake. At the same time, there are also indigenous fish such as Dianchi high-backed crucian carp, Yunnan light-lipped fish, Dianchi silver white fish and so on - they have all experienced the "ups and downs of fate" that disappeared and reappeared in Dianchi Lake.
Pan Xiaofu introduced that the golden mackerel is in the upper layer of the food chain of Dianchi Lake, preying on small fish and shrimp such as silver fish, small fish and shrimp eat plankton, and plankton is the largest consumer of algae, and it is algae that causes water bodies such as green paint and smell. As the most important flagship species in Dianchi Lake, the flourishing of the goldenrod can improve the structural ratio of fish communities and help other indigenous fish to restore their populations.
However, after ten years of release, the population recovery of the golden mackerel in Dianchi Lake is still not ideal. Although people found stocks of stocked golden herring in the upper reaches of the Panlong River, "no small fry were found, indicating that the artificially released fish may not have bred", Wang Xiaoai was a little disappointed. Why? Yang Junxing analyzed that one is that the number of releases is small, and it is like finding a needle in a haystack in Dianchi Lake; the second is that the overall ecological environment of Dianchi Lake is not healthy and ideal - for the golden thread catfish, the migratory environment of Longtan and Dark River is still blocked, and the "natural spawning field" is not restored enough.
The researchers found an interesting phenomenon: the Longtan stream in many temples along the Dianchi Lake can also retain some wild species of indigenous fish, and the surrounding ecology is less damaged. Pan Xiaofu said: "Academically, we have noticed the protective effect of the 'Sacred Mountain Sacred Realm' on species, and in the final analysis, it is due to the psychology of awe, and people's understanding of nature is 'de-utilitarian'. ”
In the vicissitudes of the sea, it is not easy to restore the "habitat" of the Dianchi lake golden thread catfish! But if biodiversity is used as a measure, the Dianchi Lake golden line catfish is like a touchstone and navigational beacon, inspiring people to move towards a higher level of Dianchi Lake governance! Taking Longtan as an example, some of them have dried up and annihilated, some have been cut off into water intakes, and some are not clear to whom to manage, and the Longtan connected to Tuna was once part of Dianchi Lake. Pan Min believes: "If the engineering governance is effective and obvious, then the ecological governance and biodiversity restoration of Dianchi Lake must be embroidered for a long time, and the trivial work must respect science." ”
Starting from the governance of ecology, people will face the balance between innovative adjustment of ideas and indicators. For example, the current lake governance pays great attention to water quality indicators, and several types of water even determine the success or failure of the work. From this baton, the most effective approach is to build a large number of buildings, and tend to artificially maintain the high water level of the lake. However, a pool of clear water does not necessarily represent biodiversity and lake health, and from a systematic point of view, high maintenance water levels may inhibit aquatic plant growth and flood shallows where fish spawn. Yang Junxing reminded: "The early governance has laid a good foundation, but if there is no reproduction of indigenous organisms and the self-purification function of the lake, the cost of artificially maintaining water quality is very large." ”
However, the selection of indicators such as biodiversity to measure lake governance is both a phased issue and an operational issue. Pan Min admitted that the idea of Daofa nature and one lake and one policy sounds quite beautiful, but how should the complex index system be designed to be scientific? Can such an indicator system be implemented? Can a quantitative assessment be used for assessment? Pan Min said: "The research on indicators in this area of Dianchi Lake has just begun, but it is also the focus and direction of future work. ”
General Secretary Xi Jinping profoundly pointed out: Dianchi Lake is a jewel embedded in Kunming, we must take out the momentum of holding on to the green mountains and not relaxing, in accordance with the concept of landscapes, forests, fields, lakes and grasses is a community of life, strengthen comprehensive management, systematic governance, source governance, and redouble our efforts to do a better job in the governance of Dianchi Lake.
Yang Junxing understands this: the future fate of the Dianchi lake golden line catfish depends on the effectiveness of "comprehensive management, systematic governance, and source governance".
The way to use: "swimming back to the table" is the most reliable protection
In 1638, the great traveler Xu Xiake entered Yunnan from Shengjingguan and stopped in Kunming. In this year, he wrote the "You Taihua Mountain Chronicle", which said that the goldfish "is no more than four inches large, the fat is in the middle, and the head and tail of gold are like a thread, which is the treasure of Dianchi Lake". This is the Dianchi lake golden ray catfish.
Pan Xiaofu Xingchong led the reporter to see a longtan at the foot of Kunming's West Mountain, and he deduced that Xu Xiake had passed by there, climbed the Taihua Temple, and wrote "The Record of Touring The Taihua Mountain". Local community officials also intend to introduce the golden thread catfish and continue to write a period of history. But the scene was disappointing: the Longtan That may have bred the Golden Thread Catfish has dried up, and the tourism development has also made the stream unrecognizable, which is very different from the original ecological beauty described by Xu Xiake in the past.
However, the villagers of Baicao Village in Biji Town, Xishan District, are also actively busy with the Dianchi Lake Golden Thread Catfish. Baicao Village is located on the edge of Dianchi Lake, the village has two large and small dragon ponds, and there have always been Dianchi Lake golden thread catfish to survive. The village is clean and tidy, and I want to use the golden thread to create rural tourism. When the reporter arrived, the longtan in the village had just been dredged. Wang Xue, the leader of the group, said: "The golden line catfish swim back to the dark river to hide, and after the construction, tourists can see the wild golden line catfish, which is the highlight of our Baicao Village." ”
How to mobilize the masses to love and take the initiative to restore the living environment of the golden thread catfish? Pan Min believes that it is important to achieve "benefit-sharing" in the conservation of biodiversity and biological governance in Dianchi Lake - it is very important to benefit from it and more talents will participate.
More than ten years ago, Yang Junxing had vigorously promoted the three-dimensional breeding mode of "sea cauliflower- golden thread catfish - mussels", which is an enlarged "ecological tank", hoping to be applied to the farmland around Dianchi Lake, "four retreats and three returns", and also strived to build a test field for the project. But as the project was completed, the pattern stopped. In the eyes of his old classmate Zhou Wei, a retired professor at Southwest Forestry University, although the "ecological tank" culture is good, it is a bit "not in time" - at that time, how to quickly make the water clear in Dianchi Lake was the most urgent task, and the effect of flower fish mussels was slow. And now Professor Zhou Wei feels that the time for "ecological tank" breeding has come. He said: "The advantage of this model is that the villagers benefit, selling sea cauliflower and golden thread catfish can make money, and can purify the water quality of Dianchi Lake to enhance biological diversity, which is worth promoting in 'rotational grazing' in Dianchi Lake." ”
With the transformation of Dianchi Lake governance from one lake governance to watershed governance, it is undoubtedly of far-reaching significance to develop the economic value of Dianchi Lake golden line catfish and let more "three-dimensional wetland ecological tanks" bloom in the river basin to replace other industries. But is this way possible? What are the challenges?
After 13 years and 4 consecutive generations, Yang Junxing's team finally cultivated the breeding species of Dianchi Golden Thread Based on the wild Dianchi Golden Thread Catfish: "Catfish You No. 1". The growth rate of "Catfish No. 1" is 40% faster than that of wild species, and the intermuscular spines are optimized by 80%, which can be directly chewed and swallowed when cooked, and can be cultivated on a large scale.
In May 2018, "Guiyou No. 1" passed the certification of the Ministry of Agriculture, becoming the first new aquaculture species in Yunnan Province to be certified by the state. In the previous decade, the Ministry of Agriculture approved 182 new aquatic varieties, but Yunnan was left behind, but its abundant fish resources could not be transformed into industrial advantages.
Yang Junxing said: "An endangered fish can produce benefits, swimming back to the people's table, is the most reliable protection, but also to promote the ecological governance of lake basins." "So the variety is there, is the marketing open?"
More than 200 kilometers out of Kunming to Huize County, Qujing City. Walking through the belly of Wumeng Mountain, tracing up the source of the Bison Stable River, the sound of water is noisy, all the way to the mountain flowers, and then open for another hour, I came to the breeding base of The Dianze Aquatic Products Company and met Li Jianyou.
Li Jianyou has long cooperated with Yang Junxing's team and is committed to the industrialization promotion of Dianchi golden line catfish. The base culture is mainly sturgeon, but more than 40 species of Yunnan indigenous fish are raised, which are often released to the nearby Niulan River, which is also the starting point of the Dianchi Lake water replenishment project.
Although the market price of Dianchi Lake golden line catfish is as high as 670 yuan a kilogram, the sales volume is limited and the promotion is not open. Li Jianyou concluded: First, the fish is small, more than thirty kilograms, not like large fish to do "hard dishes" to sell; the second is that the growth period of the breeding species is still slow, growing to more than 30 grams in two years; the third is that the popularity is not high, after all, it has only been one or two years since it has become a new breed.
However, Li Jianyou, who usually loves to study, pondered and practiced the "micro-flow rice field breeding golden line catfish": set up water outlets and inlets in one side of the rice field, and dig a ditch on the side of the rice field. Through rice field water volume control, the water temperature can be adjusted to affect the fish's eating habits and breeding period; when the rice is cut, the fish enter the ditch, overcoming the seasonality of rice field fish farming. Li Jianyou said: "This set of technology is simple and mature and easy to copy, and the scale of gold wire catfish culture is no longer a problem, but it still needs the joint efforts of the government and the people to promote it, and there is still a long way to go." ”
The invention of Li Jianyou's "raising indigenous fish in rice fields" coincides with Yang Junxing's idea of "three-dimensional wetland". Yang Junxing introduced that Yunnan has many mountainous areas, less large water surfaces, and many small pit ponds and streams with clean cold water, which is suitable for the growth of local indigenous fish. How does yunnan, the largest number of endemic fish species in the country, benefit the border ethnic areas? The industrialization of Dianchi lake golden line catfish is not only useful for the ecological governance of the Dianchi Lake Basin, but also a "pathfinder" for environmental protection and utilization in the province.
The goal of sustainable use of the Dianchi lake golden herring is precisely the ecological restoration under the "benefit-sharing". If you've seen dianchi lake before, you know how worthwhile this recovery is. Liu Hongkuan, an 85-year-old man in Baicao Village, recalled that when he was young, there were more fish in the water than leaves, and goldfish were active at night, standing in the ditch and hitting their feet, not afraid of people at all. He said that goldfish are like satin clothes, and they are more expensive than ordinary fish, which is delicious! Baicao Village is not much, and the gold thread fish in the Golden Thread Cave are called many - "At that time, Dianchi Lake, oh, born to raise, hungry people"!
From the old man's intoxicated expression, the reporter seemed to see the Dianchi Lake that was "full of joy and emptiness": there were reeds in the sky and the ground, dotted with some green feathers and Danxia; there was fragrant rice and ten thousand acres of clear sand; there could be watching the fishing fires of the half-river, the two rows of autumn geese and the falling smoke. Up close, flocks of golden thread catfish pass between Longtan Creek and Dianchi Lake, shining in the sun, "the beginning and tail of gold are like a line"...
At this time, the reporter understood the meaning of Pan Xiaofu's words. He said: "Protecting the Dianchi lake golden thread catfish is also protecting our nostalgia." ”