Suchergebnisse

AbstractLake Dianchi is a large lake, which is listed in the 'Three Important Lakes Restoration Act in China'. The water quality has deteriorated from class II in the 1970s to class V today, with an attendant increase in the frequency and intensity of the formation of blue algae blooms. From 2003 to 2006, a water quality monitoring programme was implemented for eight regional zones in Lake Dianchi. It monitored the following substances: carbon (C), nitrogen (N), phosphorus (P), sulphur (S), calcium (Ca), magnesium (Mg), iron (Fe), potassium (K), sodium (Na), zinc (Zn), copper (Cu), manganese (Mn) and chlorine (Cl), together with water temperature, pH, total hardness and total salt content. Data were analysed using regression models to determine the impacts of these substances and conditions for the formation of blue algae bloom, and to assess their relationship with chlorophyll a. The results showed a significant relationship between chlorophyll a and C, P, N, Cl, Fe, Mg, water temperature, pH, total hardness and total salt. There was no significant relationship between chlorophyll a and total manganese (TMn), Mn, sulphate (SO42−), soluble total manganese STMn, Ca, Zn, K, Na and Cu. The study showed that the concentration of chlorophyll a in different regions of the lake was different, indicating that the mix of chemicals in a region has a different impact on pollution levels throughout Lake Dianchi.