Identifying the effects of environmental factors on benthic diatom assemblages in typical tributaries of Taizi River, northeast China using the CCA method

Abstract

Rivers are one of the important sources of water supply and benthic diatoms are a crucial part of the river ecosystem. It is necessary to investigate the effects of environmental factors on river benthic diatoms. In this study, the benthic diatom assemblages, environment factors including physical–chemical factors, and altitude factors were intensively investigated in gradient tributaries of Taizi River, northeast China. The CCA method was used to explore the relationships between benthic diatom assemblages and environmental factors. The results demonstrated that the altitude, distance to river source, water temperature, TN, SS, average water depth, TP, and CODCr were the environmental factors that accounted for significant (P < 0.05) portions of the total variance in species composition. These suggest that the diatom assemblage is a good indicator of environmental change, and it is not only sensitive to physical–chemical factors but also significantly sensitive to large-scale factors (e.g., altitude, distance to river source). HIGHLIGHTS The diatom assemblage is a good indicator of environmental change.; Altitude, distance to river source, water temperature, TN, SS, average water depth, TP, and CODCr were the environmental factors that determine the community structure of diatoms.; The diatom assemblage is also sensitive to large-scale factors (e.g., altitude, distance to river source).;

Keywords

• benthic diatom
• cca
• taizi river