The ecological degradation and restoration of Baiyangdian Lake, China

Systematic investigations into the distribution of aquatic species and vari ation of community structure in Baiyangdian Lake, the largest natural fresh water body in the Northern China Plain, were conducted during 1993-1994. Wa ter quality of this shallow and eutrophic fake was assessed by qualitative and quantitative analyses of aquatic communities. Chemical and biological d ata in 1990s were compared with data from 1950s, 1970s and 1980s. Results f rom this research showed that Baiyangdian Lake was highly enriched by ammon ia (NH3), nitrate (NO3) and phosphate (PO4) at the present time. The negati ve responses to increase degradation included: (1) a clear decrease in biod iversity; (2) a dramatic increase in individual abundance of tolerant speci es; and (3) a great decline in aquatic products in the recent years. A demo nstration project for water pollution control and ecological restoration in Baiyangdian Lake is proposed.