The present study aimed to reveal correlations between environmental events and geochemistry variation and ecological risks of the coastal Tajan River. Sediment quality indices (Cf, Cd, Er, and RI) were applied to achieve the research objectives based on the concentration of toxic metals (As, Cd, Cr, Cu, Ni, Pb, Zn). The probably effective level is based on the concentration of As, Cr, and Ni observed. The coastal zone and the urban sector of the river have experienced a moderate ecological risk since 1975, especially during wet seasons (1988–1997) with a mean sedimentation rate of 2 cm/year. A significant correlation (r=0.439–0.633, p-values < 0.0001) between the toxic metal concentration and the Caspian Sea level fluctuation was obtained. The lowest concentration of toxic metals coincided with the high stand water level. Management practices recommend controlling toxic metals (As, Cd, Ni, Cr, Pb) from the sources and dredging of retention pounds along the Tajan River.

本研究旨在揭示环境事件与塔詹河沿岸的地球化学变化和生态风险之间的相关性。沉积物质量指标（Cf、Cd、Er和RI）用于实现基于有毒金属（As、Cd、Cr、Cu、Ni、Pb、Zn）浓度的研究目标。可能的有效水平基于观察到的 As、Cr 和 Ni 的浓度。自 1975 年以来，沿海地区和河流城市部分经历了中等生态风险，特别是在雨季（1988-1997 年），平均沉积率为 2 cm/年。显着相关性 ( r =0.439–0.633, p-values < 0.0001) 在有毒金属浓度和里海水平波动之间获得。有毒金属的最低浓度与高位水位相吻合。管理实践建议从源头控制有毒金属（As、Cd、Ni、Cr、Pb）并疏浚塔詹河沿岸的滞留点。