tailieunhanh - BIOGEOCHEMICAL, HEALTH, AND ECOTOXICOLOGICAL PERSPECTIVES ON GOLD AND GOLD MINING - CHAPTER 5

Nồng độ vàng trong các vật liệu khác nhau vô sinh thu thập trên toàn thế giới (nước mưa, nước biển, lakewater, bụi không khí, đất, tuyết, nước thải bùn, trầm tích) được liệt kê và thảo luận trong chương này, cũng như dữ liệu tương tự cho các nhà máy trên cạn và thủy sản, động vật không xương sống trên cạn và dưới nước , cá, và con người (Eisler 2004). 5,1 phi sinh học vật liệu Nồng độ vàng trong không khí, lớp vỏ của trái đất, nước ngọt, nước mưa, nước biển, trầm tích, bùn thải, tuyết, đất, đá. | CHAPTER 5 Gold Concentrations in Field Collections Gold concentrations in various abiotic materials collected worldwide rainwater seawater lakewater atmospheric dust soils snow sewage sludge sediments are listed and discussed in this chapter as well as similar data for terrestrial and aquatic plants terrestrial and aquatic invertebrates fishes and humans Eisler 2004 . ABIOTIC MATERIALS Gold concentrations in air the earth s crust freshwater rainwater seawater sediments sewage sludge snow soil and volcanic rock are summarized in Table . Most gold in ocean surface waters comes from fallout of atmospheric dust. Riverine sources of gold into seas and oceanic coastal waters are minor as judged by studies of manganese transport Gordeyev et al. 1997 . Dissolved gold was discovered in seawater in 1872 and many unsuccessful attempts to recover the gold commercially from seawater have since been made Puddephatt 1978 . The most famous attempt was made by German scientists in the years 1920 to 1927 with the intention of paying off the German war debt incurred during World War I. The method was based on reduction to metallic gold using sodium polysulfide Puddephatt 1978 . Unfortunately the German calculations of pg Au L were 100 to 400 times higher than the recently calculated range for dissolved oceanic gold of to pg L Gordeyev et al. 1997 . At these low concentrations it was not possible to directly determine what gold species were present. However based on redox potentials of gold compounds and seawater composition it is probable that AuCl2-predominates with smaller amounts of AuClBr- as well as bromo- iodo- and hydroxy complexes of Au Puddephatt 1978 in oxidation states of Au0 Au and Au 3 Karamushka and Gadd 1999 . Dissolved gold may be usable as a tracer of hydrothermal influence on bottom waters near vents. Concentration of gold in bottom water samples of the mid-Atlantic ridge in 1988 near hydrothermal vents was pg L vs. pg L at