Case study on rehabilitation of a polluted urban water body in Yangtze River Basin

Abstract

In the past three decades, the fast development of economy and urbanization has caused increasingly severe pollutions of urban water bodies in China. Consequently, eutrophication and deterioration of aquatic ecosystem, which is especially significant for aquatic vegetation, inevitably became a pervasive problem across the Yangtze River Basin. To rehabilitate the degraded urban water bodies, vegetation replanting is an important issue to improve water quality and to rehabilitate ecosystem. As a case study, a representative polluted urban river, Nanfeihe River, in Hefei City, Anhui Province, was chosen to be a rehabilitation target. In October 2009 and May 2010, 13 species of indigenous and prevalent macrophytes, including seven species emergent, one species floating leaved, and five species submersed macrophytes, were planted along the bank slopes and in the river. Through 1.5 years' replanting practice, the water quality and biodiversity of the river had been improved. The concentrations of total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH 4 + -N) declined by 46.0, 39.5, and 60.4 %, respectively. The species of macrophytes increased from 14 to 60, and the biodiversity of phytoplankton rose significantly in the river (p<0.05). The biomasses of zooplankton and benthos were also improved after the vegetation replanting. The study confirmed that vegetation replanting could alleviate the increasing water pollution and rehabilitate the degraded aquatic ecosystem. The case study would be an example for polluted urban waters restoration in the middle-downstream area of Yangtze River Base.

Phytotoxicity assessment of atrazine on growth and physiology of three emergent plants

“…The plants commonly distributed in ponds, lakes, ditches, and quiet streams and being used as species to improve water quality and rehabilition of aquatic ecosystems for the removal of nitrogen and phosphorus (Vymazal 2013;Wu et al 2013). Our objective was to determine growth and physiological responses of emergent plant exposure to atrazine, contributing to the phytotoxicity assessment database.…”

Acclimation of Hydrilla verticillata to sediment anoxia in vegetation restoration in eutrophic waters

“…Ecological restoration of eutrophic waters has been a research focus in China over the past decade, and rehabilitation of aquatic vegetation is one of the most important issues (Dai et al 2012;Wu et al 2013a). Low light availability resulting from the overgrowth of algae or turbidity in eutrophic water bodies is considered the main factor responsible for the failure of submerged macrophyte restorations.…”

Enzyme activities in pilot-scale constructed wetlands for treating urban runoff in China: temporal and spatial variations

“…Two parallel pilot-scale ICW systems (each was composed of a IVCW and HSSF-CW in series) were constructed on the bank of Nanfeihe River, a tributary and the biggest pollution source of Chaohu Lake, in Heifei, China, which was described in detail by Wu et al (31˚52´40.89´´N, 117˚13´22.89´´E; elevation, 13 m; called site 4 in their report) [21,22].…”