A field study of the relationship between sulfide-bound metals and bioaccumulation by Limnodrilus sp. in a heavily polluted river.
Acid volatile sulfide (AVS) has been regarded as an important factor controlling metal bioavailability in anoxic sediments, but its effect on metal accumulation under natural conditions is poorly understood. Here, a field study of the influence of AVS on metal accumulation by Limnodrilus sp. in a heavily polluted river is provided. Most of the study area was subject to anaerobic and strongly reducing conditions, and the concentration of trace metals in surface sediments was high, as were the concentration of AVS and simultaneously extracted metals (SEM; average AVS = 20.3 μmol g(-1), average ∑SEM5 = 9.42 μmol g(-1); ∑SEM5 refers to the sum of SEMCd, SEMCu, SEMPb, SEMNi, and SEMZn). Only a few species and small quantities of benthic invertebrates were found, and Limnodrilus sp. was dominant. There was no correlation between trace metal accumulation and (SEM-AVS), and in stations where (SEM-AVS) <0, the absolute value of bioaccumulation was high (average ∑BIO5 = 4.07 μmol g(-1); ∑BIO5 refers to the sum of BIOCd, BIOCu, BIOPb, BIONi, and BIOZn), indicating that there was no relationship between (SEM-AVS) and metal accumulation in Limnodrilus sp. This was likely because Limnodrilus sp. ingest sediment particles as their main food source, so pore water metals play a minor role in their bioaccumulation (BIO) of materials. However, ∑BIO5 was significantly correlated with ∑SEM5 (r = 0.795, p < 0.01), revealing that the large number of sulfide-bound metals (SEM) in sediments may play an important role in metal accumulation in Limnodrilus sp., which can assimilate sulfide-associated metals by the help of the digestive fluids in the digestive systems.
School of Civil Engineering and Transportation, South China University of Technology, Guangzhou, 510641, China, hjlifeng@scut.edu.cn.
Feng
F
Li
Xiang-Yun
XY
Zeng
Yun-Jun
YJ
Yu
Chang-Hua
CH
Wu
Ge
G
Mai
Wei-Wei
WW
Song
Yan-Mao
YM
Wen
Zhi-Peng
ZP
Duan
Jia-Yu
JY
Yang
D000818:Animals; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry; D007448:Invertebrates; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D009835:Oligochaeta / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry*; D013440:Sulfides / Q000032:analysis / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*
D019216:Metals, Heavy; D013440:Sulfides; D014874:Water Pollutants, Chemical