Pacific Geographical Institute, Russian Academy of Sciences, Far Eastern Branch, 690041, Radio Str., 7, Vladivostok, Russia.
State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, PR China.
Sci Total Environ. 2014 Nov 15;499:196-211. doi: 10.1016/j.scitotenv.2014.08.015. Epub 2014 Sep 2.
This paper compares the distributions of dissolved and particulate forms of Mn, Fe, Ni, Cu, Zn, Cd, and Pb in the estuaries of the largest rivers in East Asia: the Amur River and the Changjiang (Yangtze River). High suspended solid concentrations, elevated pH, and relatively low dissolved trace metal concentrations are characteristics of the Changjiang. Elevated dissolved Fe and Mn concentrations, neutral pH, and relatively low suspended solid concentrations are characteristics of the Amur River. The transfer of dissolved Fe to suspended forms is typical in the Amur River estuary, though Cd and Mn tend to mobilize to solution, and Cu and Ni are diluted in the estuarine system. Metal concentrations in suspended matter in the Amur River estuary are controlled by the ratio of terrigenous riverine material, enriched in Al and Fe, and marine biogenic particles, enriched in Cu, Mn, Cd, and in some cases Ni. The increase in dissolved forms of Mn, Fe, Ni, Cu, Cd, and Pb compared with river end-member is unique to the Changjiang estuary. Particle-solution interactions are not reflected in bulk suspended-solid metal concentrations in the Changjiang estuary due to the dominance of particulate forms of these metals. Cd is an exception in the Changjiang estuary, where the increase in dissolved Cd is of comparable magnitude to the decrease in particulate Cd. Despite runoff in the Amur River being lower than that in the Changjiang, the fluxes of dissolved Mn, Zn and Fe in the Amur River exceed those in the Changjiang. Dissolved Ni, and Cd fluxes are near equal in both estuaries, but dissolved Cu is lower in the Amur River estuary. The hydrological and physico-chemical river characteristics are dominated at the assessment of river influence on the adjoining coastal sea areas despite differences in estuarine processes.
本文比较了东亚最大河流——黑龙江和长江的河口区溶解态和颗粒态形式的 Mn、Fe、Ni、Cu、Zn、Cd 和 Pb 的分布。高悬浮物浓度、高 pH 值和相对低的溶解态痕量金属浓度是长江的特点。高溶解态 Fe 和 Mn 浓度、中性 pH 值和相对低的悬浮物浓度是黑龙江的特点。在黑龙江河口区，溶解态 Fe 向悬浮物转化是典型的，尽管 Cd 和 Mn 倾向于向溶液中迁移，Cu 和 Ni 在河口系统中被稀释。黑龙江河口悬浮物中金属浓度受陆源河流物质与富 Al 和 Fe 的比值控制，而海洋生物成因颗粒则富含 Cu、Mn、Cd，在某些情况下还富含 Ni。与河流端元相比，长江河口区 Mn、Fe、Ni、Cu、Cd 和 Pb 的溶解态增加是独特的。由于这些金属的颗粒态占主导地位，因此长江河口悬浮物中金属的总体浓度并不能反映颗粒-溶液相互作用。Cd 是长江河口的一个例外，其中溶解态 Cd 的增加与颗粒态 Cd 的减少相当。尽管黑龙江的径流量低于长江，但黑龙江的溶解态 Mn、Zn 和 Fe 通量超过了长江的通量。尽管在两个河口区 Ni 和 Cd 的通量相近，但在黑龙江河口区 Cu 的通量较低。尽管在河口过程方面存在差异，但在评估河流对毗邻沿海海域的影响时，水文和物理化学河流特征占据主导地位。
