After the "four retreats, three returns and one protection" on the shores of Dianchi Lake, for the first time in the history of Dianchi Lake, the lake has been regressed
With the restoration of the wetlands around Dianchi Lake, the variety of flora and fauna in Dianchi Lake has increased significantly. Among them, the number of birds on the shores of Dianchi Lake has increased from 96 in 2012 to 139 at present, and the number of plant species has increased from 238 in 2010 to 290 at present. Aquatic plants such as sea cauliflower and indigenous fish species such as the Dianchi lake golden-threaded catfish have reappeared, and the endangered national rare birds, the painted ibis and white-browed duck, and the wild cormorant that has disappeared for more than 30 years have reappeared in Dianchi Lake
Wen | Pang Mingguang, a reporter for the "Lookout" news weekly
The sky is blue and the water is blue, the grass is green, the fish are playing in the water, the water birds are foraging in the grass... In mid-October, it is late autumn, and the Baofeng Peninsula wetlands on the east bank of Dianchi Lake in Kunming, Yunnan Province, are still full of life.
On 11 October, the fifteenth Conference of the Parties to the Convention on Biological Diversity (COP15) opened in Kunming. As one of the outdoor exhibition and display projects of COP15, the Baofeng Peninsula Wetland, which covers an area of 1633.8 acres, showed the participants from all over the world the protection and management effects of Dianchi Lake and lakeside wetlands, as well as the original natural features and biodiversity of Dianchi Lake.
Wetlands are known as the "kidneys of the earth". For Dianchi Lake, a semi-enclosed plateau lake with a history of more than 3 million years, the wetland is also the "kidney" that maintains the ecological environment and biodiversity of this lake.
Since 2008, Kunming has made great efforts to promote the construction of Dianchi Lake Wetland, and built a 62,900-mu Dianchi Lake Ecological Belt dominated by lakeside wetlands, which is the first time in the history of Dianchi Lake to achieve the lake's entry and retreat. A closed ecological belt with an average width of about 200 meters and a vegetation coverage rate of more than 80% is like a necklace made of emeralds, decorating Dianchi Lake with vitality.
The reclaimed water discharged from the water purification plant flows into Dianchi Lake after being purified by the wetlands of baofeng Peninsula
From vanishing to rejuvenating
"Five hundred miles of Dianchi Lake, rushing to the bottom of the eyes, draped on the shore, happy and empty... He Feng, chief engineer of the Dianchi Plateau Lake Research Institute in Kunming City, said that from the 180-character Grand View Building Long Lian made by the Qing Dynasty poet Sun Qiweng, people can imagine the beauty of Dianchi Lake and the lakeside wetland hundreds of years ago.
He Feng said that in the past, the wetland area around Dianchi Lake was very large, but in the 1960s and 1970s, in order to increase grain production, large-scale reclamation of lakes around Dianchi Lake was transformed into farmland and fish ponds. By the end of the 1990s, the original wetlands around Dianchi Lake had been basically replaced by farmland, greenhouses and fish ponds. "Natural wetlands are almost completely lost, only sporadically distributed."
Since 2008, in order to restore the Dianchi Lake Wetland, Kunming Has launched the ecological construction work of "four retreats, three returns and one protection" on the shore of Dianchi Lake with the construction project of the Wetland around the Lake outside the Dianchi Lake as the core. "Four retreats" means retreating from ponds, fields, check-outs, and retreating people, "three returns" that is, returning forests, wetness, and lakes, and "one protection" that is, protecting water. In accordance with the principle of "minimizing manual intervention and maximizing natural recovery", as of now, Kunming has completed the withdrawal of 48,000 mu of ponds and fields, checked out 2.33 million square meters, and retired 32,000 people; after actual measurement and review, a total of 62,900 mu of Dianchi Lake Ecological Belt with lakeside wetlands as the mainstay has been built.
"In the past, the area around Dianchi Lake has always been a lake retreating, and the ecological environment of the lake has been continuously damaged. The construction of the lakeside wetland is the first time in the history of Dianchi Lake that the lake has been entered and retreated. Fu Wen, director of the Kunming Dianchi Lake Management Bureau, said.
Ye Xiangqiang, designer of the China Academy of Urban Construction, the designer of the Baofeng Peninsula wetland, introduced that 12 plant communities with local characteristics of Yunnan were restored in the wetland, with a total of 101 plant species, including the native submerged plant community of Dianchi Lake and the native sea cauliflower community, etc., to create an "aquatic-wet-terrestrial" composite ecological belt.
In the hidden bird watching gallery of the Baofeng Peninsula wetland, the reporter saw birds such as egrets, pheasants, and black water chickens playing at the water's edge from time to time, and the wetland with fertile grass and water became a paradise for birds. Liu Jialin, deputy director of the Water Affairs Bureau of Guandu District, Kunming City, introduced that indigenous fish species such as Dianchi Lake golden-threaded catfish and Kunming split-bellied fish were stocked in the wetland. "With these small fish and shrimp, as well as local fruit trees such as large dates and wild persimmons, birds can be attracted to feed."
Indigenous fingerlings have re-emerged
It is understood that the restoration of the lakeside wetland is of great significance to Dianchi Lake.
On the one hand, wetlands can purify the pollutants flowing into Dianchi Lake, especially for non-point source pollution in the rainy season. He Feng said that the reason why wetlands are called "kidneys of the earth" is because after various sewage flows into wetlands, plants in wetlands can not only adsorb particulate pollutants, but also decompose and absorb pollutants such as nitrogen and phosphorus in sewage, reducing the pollution load of lakes. In addition, wetland plants can also absorb carbon dioxide and harmful gases in the air, effectively fixing most of the carbon in plant residues.
In the Xinghai Peninsula wetland of Dianchi Lake, the reporter observed the purification effect of the wetland on the water quality of the Dianchi Lake. Upstream of the Xinghai Peninsula wetland is the seventh and eighth water purification plants in Kunming. Wu Guosha, head of the Lakeside Wetland Protection and Management Center of guandu District Water Affairs Bureau, introduced that after the reclaimed water treated by the water purification plant flows into the wetland, it flows into the wetland after layers of purification such as cobblestones, metasequoia, reeds, grasslands and so on in the wetland, and its water quality can be improved from class V to class IV., effectively reducing the pollution load of the lake.
Wetlands, on the other hand, are the most biodiverse system in the world. According to reports, wetlands cover only 6% of the earth's surface, but provide a living environment for 20% of the known species on the earth, which plays an important role in maintaining global species diversity and building a complete ecosystem.
Cheng Lianyuan, secretary of the Kunming Municipal Party Committee, said that at present, a closed ecological belt with an average width of about 200 meters and a vegetation coverage rate of more than 80% in the area has been initially constructed in the Area of Dianchi Lake. With the restoration of the wetlands around Dianchi Lake, the species of animals and plants on the shores of Dianchi Lake have increased significantly in recent years. Among them, the number of birds on the shores of Dianchi Lake has increased from 96 in 2012 to 139 at present, and the number of plant species has increased from 238 in 2010 to 290 at present. Aquatic plants such as sea cauliflower, which have disappeared for many years, and indigenous fish species such as the Dianchi lake golden herring, have reappeared, and the endangered national rare birds, the colored ibis and the white-browed duck, and the wild cormorant that has disappeared for more than 30 years have also reappeared in Dianchi Lake.
"The Dianchi Lake in that memory is back"
Cyanobacteria outbreaks, deterioration of water quality, stink... For a long time in the past, when Kunming people mentioned Dianchi Lake, they could only sigh helplessly. People passing by Dianchi Lake are always covered by the stench and leave in a hurry.
In recent years, under the systematic treatment of a number of treatment projects, the water quality of Dianchi Lake has improved significantly. In 2016, the water quality of the whole lake of Dianchi Lake was upgraded from inferior class V. to class V. for the first time, and the hat of "inferior class V. was removed; from 2018 to 2020, the water quality of the whole lake of Dianchi Lake reached class IV. for three consecutive years.
It is understood that the restoration and protection of The Dianchi Lake wetland in Kunming is advancing in the direction of standardization and standardization. Fu Wen introduced that since 2018, Kunming has formulated and promulgated four local standards for the construction of Dianchi Lakeside Wetland, monitoring procedures, management and protection procedures and plant application directory, filling the gap in the design, construction, monitoring, management and protection of wetlands in Kunming.
In addition, in order to standardize the protection measures and behaviors of waterbird habitats in Dianchi Lake, provide technical support for the restoration of waterbird habitats, and effectively protect waterbirds in Dianchi Lake Wetland, Kunming City has also formulated local standards for "Restoration of Waterbird Habitat in Dianchi Lakeside Wetland". "This is also the first standard for the restoration of waterbird habitats in China." He Feng said.
Under the comprehensive treatment, Dianchi Wetland has become a beautiful business card of Kunming and has repeatedly won awards at home and abroad. For example, Haidong Wetland and Laoyuhe Wetland were rated as "the most beautiful wetlands in China", and Dounan Wetland and Nandianchi National Wetland Park were awarded the International Federation of Landscape Architects' Outstanding Award for Stormwater Management in the Asia-Africa Middle East region, as well as the Outstanding Award for Wildlife, Biodiversity, Habitat Improvement or Construction, respectively.
With the improvement of water quality, the wetlands around Dianchi Lake are open to the public free of charge, becoming a good place for citizens and tourists to relax and vacation. People walk, ride and fly kites in the wetlands to get up close and personal with the "Mother Lake". According to Kunming Dianchi Lake Investment Co., Ltd., during this year's National Day holiday, Chenggong Dounan Wetland, Guandu Wangguan Wetland and South Dianchi National Wetland alone received about 136,000 tourists.
"The Dianchi Lake in that memory is back." Chen Jiajia, a kunming resident in his late forties, said that when he was a child, his father would take him to swim in dianchi Lake, and after swimming up to the shore, his father would always buy him a bottle of hawthorn soda. Chen Jiajia is a kayaking enthusiast, and when he is not busy on weekdays, his favorite thing to do is to meet three or five friends and kayak in the wetlands of Dianchi Lake and the boathouse river upstream.
In 2019, a team of more than 40 partners of Chen Jiajia and kayak clubs became one of the 100 "Citizen River Chiefs" teams in Kunming. Since then, he and his partner have often kayaked, collecting garbage in the water while advising the citizens fishing on the shore. "Such a beautiful Dianchi Lake, wetlands, rivers, we have the obligation to protect it." I'd rather offend people than Dianchi. Chen Jiajia said. ■