A study on the characteristics of diatoms and ecological environment pollution in the main water of Tianjin, China

Sugur Enh,Ziyao Yang,Bo Liu,Dexuan Lan,Ping Cuo Dolka,Pengyi Ma,Heng Zhang,Zhifei Wang,Jing Fang,J Sun,Z Li,X Liu

doi:10.1051/e3sconf/202129003014

Abstract

Twenty lake bottom surface layers mud and water samples in the Qilihai Wetland and the Beidagang Reservoir in Tianjin were taken to do diatoms analysis. More than 6000 diatoms were identified and divided into 117 species and 28 genera. Based on the calculation of DAIpo(Diatom Assemblage to organic water pollution), the water pollution level of the Beidagang Reservoir can be divided into: Xenosaprobic, β -oligosaprobic, α -oligosaprobic, β -mesosaprobic, from clear to slightly cloudy water. The water pollution level of Qilihai wetland can be divided into: extremely oligarchy dirt belt, β oligarchy dirt belt, α oligarchy dirt belt, β Medium dirt belt, that is, the water quality is clear to slightly turbid. The water quality of the Beidagang Reservoir is clearer than that of the Qilihai Wetland. The physical and chemical indexes such as EC, pH, TN, TP and CODMn were determined for the water samples, and the correlation between DAIpo and these measured values was analyzed. The results showed that the degree of water pollution detected was consistent with the conclusion obtained by diatom analysis. The results show that the water quality of the Beidagang Reservoir and the Qilihai Wetland was mildly polluted in the spring and summer of 2019, but the eutrophication is more serious.

Highlights

Many scholars analyzed the ecological changes of water environment by using the characteristics of diatom species and their community combinations, and combine the nutritional status index, sediment pollution degree, total phosphorus content, EC, pH and other water environment factors, as well as the main component analysis method, to analyze and evaluate the aquatic ecological environment
In the 1990s, Van Dam et al revealed that the diatoms are very effective in indicating pH, salinity, organic nitrogen, oxygen saturation, humus, and eutrophication (Van Dam H,et aL 1994)
By analyzing the diatoms in the surface mud samples of the lake bottom, which were collected from the surface layer of the lake bottom from the edge of the Qilihai Wetland, the Beidagang Reservoir in Tianjin and the Duliujian River, and the physical and chemical index such as EC, PH, TN, TP and CODMn were measured

Summary

Introduction

Many scholars analyzed the ecological changes of water environment by using the characteristics of diatom species and their community combinations, and combine the nutritional status index, sediment pollution degree, total phosphorus content, EC, pH and other water environment factors, as well as the main component analysis method, to analyze and evaluate the aquatic ecological environment. Watanabe et al (1986) proposed a calculation method, DAIpo, based on adhesion diatoms to evaluate water pollution. Many scholars have made many achievements in the study of Tianjin’s wetland environment by different methods.Diatom analysis has been widely used in the restoration of paleoenvironment of the coastal plains of China, but it has been applied less in the monitoring and evaluation of water quality, especially in North China. Based on the sediment sampling of the Qilihai Wetland and the Beidagang Reservoir, diatom species were identified. By summarizing the genus of diatoms , DAIpo (Diatom Assemblage Index to organic water pollution) was calculated, and through the pollution index, the pollution degree of different water bodies in the same period is classified quantitatively

Research areas and methodology

Diatoms from the Beidagang reservoir and Qilihai wetland

Beidagang reservoir

Qilihai wetland

Conclusion