On May 28, the Datengxia Water Conservancy Hub Project carried out fish breeding and stocking activities, releasing a total of 700,000 fish fry of triangular bream, red-eyed trout and green, grass, silver carp and bighead carp, of which 100,000 triangular bream and red-eyed trout fry are the characteristic fish of the Pearl River Basin that lasted for one year and were successfully bred independently and successfully at the Datengxia Fish Breeding and Stocking Station for one year.
Wen Peng, deputy general manager of Guangxi Datengxia Water Conservancy Hub Development Co., Ltd., told reporters that triangular bream and red-eyed trout have important economic value and scientific research value in the Pearl River Basin. Through the implementation of fish breeding and stocking in natural waters, it is possible to effectively supplement the number of fish stocks in the Pearl River Basin, maintain the aquatic biodiversity of the Pearl River, and improve the water ecological environment of the basin.
Construct a water ecological protection system
The Pearl River is the second largest river in China in terms of runoff and is known as a "rich mine" of hydropower resources. In the "Hongshui River Comprehensive Utilization Plan" approved by the State Council, the Datengxia Water Conservancy Hub was identified as the last level of 10 water elevator-level developments, located in the Qianjiang section of the main stream of the Xijiang River in the Pearl River Basin, controlling 56.4% of the area of the Xijiang River Basin and 56% of the water resources of the Xijiang River. Due to its outstanding characteristics such as good regulation performance, strong power generation capacity, high power quality and great social benefits, it has always attracted much attention.
However, at the beginning of the construction of the project, it is facing huge ecological protection pressure, because the construction of the project will directly affect the spawning and survival of a variety of rare and endangered aquatic fish. Wen Peng told reporters that there are 270 species of fish distributed under the dam of the Datengxia Water Conservancy Hub Project, including 33 rare and endemic fish, including monostried eels, Uhara carp, long-rumped fish, albacore light-lipped fish, rare white turtles, lip carp, dark lip carp and so on. An important spawning ground for migratory fish in the Pearl River Basin is not far from the dam site of the Datengxia Water Conservancy Hub Project.
Wen Peng introduced that while building dams and dams on the river to benefit the people, we must also consider how to protect the local ecological environment. The dam area of the Datengxia Water Conservancy Project will block the migration of fish, and the flooding of the reservoir will also cause the fish population to retreat towards the tail and tributaries. In order to minimize the impact of barrage construction on the ecological environment and protect the number and living habits of the original aquatic fish population, the retrospective assessment and research of the environmental impact of comprehensive utilization of the river basin have been carried out before the start of the Datengxia Water Conservancy Hub Project, and two fish crossing channels distributed on the right bank of the main dam of the Qianjiang River and the sub-dam of the Nanmu River, the fish breeding and stocking station of Datengxia, the breeding and stocking station of the guest fish and the rare fish conservation center of the Hongshui River have been carried out, and artificial fish nests and artificial spawning grounds have been set up in some sections of the river. Build a comprehensive water ecological protection system.
"Fish are the owners of the river, and when we build new channels for fish, we have fully considered the applicability of fish." Wen Peng told reporters that in order to make the fish passage closest to the original natural state to the greatest extent, the designer innovated thinking, and re-optimized the fish passage of the Nanmu River sub-dam in accordance with the concept of landscape aesthetics, from the original straight plan layout to the imitation natural arrangement of twists and turns, width and narrowness, and the fish channel structure was also adjusted from ordinary concrete structure to a pile of masonry ecological structure. According to the topographic conditions on the right bank of the dam, the fish channel of the main dam of the Qianjiang River is arranged separately during the non-main flood season and the fish road during the main flood season; in order to make the fish channel smoothly pass through the fish during the operation of different conditions in the downstream water level of the reservoir, a total of 4 fish inlets are set up. "A fishway is planned and built separately in the main dam and the sub-dam of the project, and this unique double fish road layout is rare in the construction of the same type of water conservancy project in China." Wen Peng said.
At present, the natural ecological fish channel of the Nanmu River sub-dam has been completed and opened to water, and the construction of the foundation of the main dam fish road has been completed. When the project is fully completed, the two fish lanes will play a role at the same time, which can meet the needs of rare fish migrating and breeding across the dam.
Visit the "cradle of life" of fish
"We collect wild parents of triangular bream, red-eyed trout, yellowtail carp, silver carp and other fish from the Qianjiang and Xunjiang rivers for artificial breeding, and then look for suitable time to release the fry." In the induction hatching workshop of the fish breeding and stocking station in The Dateng Gorge, Dr. Yuan Ting, the technical leader, told reporters.
Since 2020, Guangxi Datengxia Water Conservancy Hub Development Co., Ltd. has cooperated with the Institute of Water Engineering Ecology of the Chinese Academy of Sciences of the Ministry of Water Resources to focus on artificial breeding research and fry rearing of rare fish, creating favorable conditions for breeding and stocking. The reporter saw at the Datengxia Fish Breeding and Stocking Station and the Hongshuihe Rare Fish Conservation Center that the breeding station and conservation center are equipped with more than 170 advanced induction ponds, foster ponds, and fry breeding tanks, nearly 20 hatchery barrels, incubators, hatchery tanks and induction workbenches, as well as outdoor broodstock ponds, fish finger ponds, and ecological fish ponds. "This is a postpartum recovery pond, a 'confinement center' for fish, and females need to recuperate like human mothers after childbirth." Dr. Yuan Ting introduced it as she walked.
Affected by the water conservancy project are migratory fish, rare and endangered protected fish, and flowing water habitat fish. In addition to the protection of migratory fish using fish passages, the Datangxia Fish Breeding and Stocking Station and the Hongshui River Rare Fish Conservation Center play a vital role in the protection and breeding of the latter two. The breeding station is mainly responsible for the artificial breeding and stocking of rare, endemic and economic fish in the river basin; the conservation center aims to build a breeding and rescue base for endangered and rare fish, takes rare fish such as Chinese sturgeon, lipped carp and Wuyuan carp as the main rescue and protection objects, carries out breeding, breeding, protection, monitoring, research, rescue and other aspects of work, and explores the breeding technology of endangered and rare fish.
Lian Hao, senior engineer of Guangxi Datengxia Water Conservancy Hub Development Co., Ltd., introduced that the fish breeding and stocking station and the rare fish conservation center will gradually establish multi-level germplasm resources protection technology such as rare and endangered fish populations, individuals, sperm eggs, embryos, cells, genes, etc. by strengthening the monitoring of fish resources, understanding and mastering the changes and evolution trends of the water ecology in the Datengxia evaluation area, which will minimize the impact of water conservancy projects on the ecology of the river basin, maintain ecological balance, and create a "cradle of life" for fish in the Pearl River Basin. "We will also carry out the second fish stocking activity in October this year, and plan to release 2.81 million fry such as Ubaran carp, red-eyed trout and triangular bream throughout the year." Lian Hao said.
With the completion of the construction of two fish crossing passages, the Hongshui River Rare Fish Conservation Center, the completion of the construction of five artificial spawning grounds, and the Dayengxia Fish Breeding and Stocking Station and the Guest Fish Breeding and Stocking Station successively put into operation, the Datengxia Water Conservancy Hub Project has basically formed a water ecological protection system of "one conservation center, double breeding station, double fish road, and five artificial spawning habitats", and has become the largest fish breeding base in the Pearl River Basin.
Content source: Zhang Zhirong, Lu Zhou, Xiong Yaozhang