Cadmium in the Amazonian Guajará Estuary: Distribution and remobilization

Inputting history of heavy metals into the inland lake recorded in sediment profiles: Poyang Lake in China

“…Moreover, the vertical metal concentration profile in river sediment can indicate not only the pollutants in sources but also the pollutants transported or contributed into reservoir through the river [1]. The history of heavy metals distribution can be assessed by taking vertical sediment core samples from river-beds, as the makeup of sediment cores reflects the geochemical and contamination history of source region, including any anthropogenic impact, and can act as a useful indicator of metal pollution flux [4,8,9]. At a regional scale, multiple terrestrial sources of natural (erosion, leaching) and anthropogenic origin (e.g.…”

“…So, the sedimentary metals could well reflect the metals contamination in aquatic system at depositing times. The vertical concentration profile of metals in sediment cores can be used to reveal the degree of metal pollution in recent decades [4][5][6]. In order to reveal detailed information on historical inputs and trends of heavy metals pollution, it is essential to establish the depositional history of the sediments through vertical profiles [7].…”

Cadmium distribution in sediment profiles of the six main rivers in southern Taiwan

“…The Cd concentration variation trend with sediment depth have similar pattern in Odiel river at southern Spain [16]. The Cd concentration in six main rivers sediment of Taiwan is very low if compared with the total mean Cd concentration of the whole Amazonian Guajará Estuary sediment samples (469 ± 164 mg/kg) [4]. But the purpose of this research was focused on the correlation and variation of Cd affected by other most seriously polluted heavy metals in river sediment of Taiwan.…”

“…The measurements of heavy metals in water and suspended solid collected from river are not conclusive due to water discharge fluctuations and low residence time. The history of heavy metals distribution can be assessed by taking vertical sediment core samples from river-beds, as the makeup of sediment cores reflects the geochemical and contamination history of a given region, including any anthropogenic impact, and can act as a useful indicator of metal pollution flux [2][3][4]. Metals concentration in sediments usually exceeds those in overlying water by three to five orders of magnitude [5].…”

Historical levels of heavy metals reconstructed from sedimentary record in the Hejiang River, located in a typical mining region of Southern China

“…A systematic study of the presence and evolution of industrial activities in mining areas, however, is difficult because of a lack of historical archives (Grousset et al, 1999). We can only analyze the field archives of past environmental conditions through the vertical concentration profiles of metals in sediment cores, and this can be used to reveal heavy metal pollution that occurred in recent decades (Nascimento et al, 2006;von Gunten et al, 1999).…”