An ecological wetland zone on the west bank of Taihu Lake near Yixing's Bafang Port is recently selected among the top 10 advanced models of ecological environment in Jiangsu province. [Photo/wxrb.com] |
An ecological wetland zone on the west bank of Taihu Lake near Yixing's Bafang Port was recently selected among the top 10 advanced models of ecological environment in Jiangsu province.
Yixing, a county-level city in Wuxi, Jiangsu, has 48 km of Taihu Lake shoreline. After investigations in various fields, dredging, and restoring lakeside ecological wetland, the zone was finally chosen to create an environment suitable for aquatic plant growth.
The project started construction in November 2014 with a total length of 1,800 meters and an area of 360,000 square meters, stretching from Dinghua Port to Shuangqiao Port's lakeside zone.
Reed is the best aquatic plant to purify water quality in Taihu Lake. However, waves will reduce the survival rate of reeds without a suitable water environment. According to Wu Guoqiang, the project director and a native of the Taihu Lake area, a cofferdam composed of ecological stakes and geotubes was the key to eliminating waves. The ecological tubes have high tenacity and can bear the impact force of nearly 1,000 kg, with silt poured inside and a U-shape. The structure can not only decrease the impact of stormy waves on the dam, but also can ensure a relative static state inside the cofferdam which will further guarantee the safety of the reeds. The security degree of the dam is also increased by the wetland acting as an ecological barrier.
Lin Dalong, an official of the department of water resources of Yixing, said that the "U" shape design of the shallow wetland also provides convenience for rapid removal of blue-green algae in Taihu Lake. Wind will blow the algae to the reeds, with parts absorbed by the reeds and others led into the algal ditch. At present, the structure and construction techniques have achieved several national invention patents and utility model patents.
The project completed construction in April 2017 with a rate of plant coverage exceeding 50 percent and greatly increased biodiversity. Wu Guoqiang said that the area has become a habitat of various birds and more fish have moved there for reproduction. Yixing spends a lot of manpower and material resources every year to continue the stability of the project.
The third-phase restoration work, covering 400,000 square meters, is nearly 70 percent complete and is expected to be finished by the end of this year. By then, a three-km ecological wetland zone will be formed on the west bank of Taihu Lake.