Untitled

Abstract

Variations in Pb concentration in lake sediments reflect changes in the fluxes of this element in the• past. A sediment core from a lake in the Pyrenees (Lake Redo at 2,240 m a.s.L, N_E Spain) was studied, with the aim of reconstructing pastenvironmenial and climatic conditions in the lake and its catchment area. The core was dated usii1g both 210 Pb and 14 C. A surface peak of Pb concentration, which was about 10 tim~s higher than the background level, was found. This peak is attributed to mining activities since the begioping of this century. Although Pb pollution due to the combustion of gasoline is expected to be present, no evidence can be deduced from Pb isotope ratios of sediment due to the masking effect of Pb from mines. A second peak appeared in a deeper layer, with a maximum Pb concentration of about 17 times higher than the background level. The origin of this peak is unclear. All evidence suggests that the ancient peak is due to mining operations in the central Pyrenees area, which were not documented historically.

Fluxes of Al, Fe, Ti, Mn, Pb, Cd, Zn, Ni, Cu, and As in monthly bulk deposition over the Pyrenees (SW Europe): The influence of meteorology on the atmospheric component of trace element cycles and its implications for high mountain lakes

“…The presentday composition of precipitation also suggests that other metals, especially Zn, may become more important from an ecotoxicological point of view. However, the potential importance of historically stored Pb, not only in sediments but also in soils [Camarero et al, 1998], as a future source to the lake ecosystems must not be neglected.…”

“…[33] Among the airborne trace elements with potential toxic effects, Pb is the one that may have caused a greater impact in the Pyrenean lake ecosystems. In the particular case of Lake Redon, its palaeorecord shows an increase in the concentration of acid extractable Pb in sediments from a background value of $20 mg kg À1 in deep sediments up to $350 mg kg À1 in the most recent sediments [Camarero et al, 1998], with an enrichment factor of more than 15. This high enrichment was likely due in a large part to local sources, i.e., mining in the vicinities of Lake Redon catchment, starting as early as the 5th century and peaking around the 7th century and the 1900 -1950s.…”

“…The atmospheric flux of trace elements has changed over time on a global scale, as proved by chronological sequences retrieved from the remotest sites on Earth, such as glacier ice from the Arctic [Hong et al, 1994] and high mountains [Van de Velde et al, 2000]. These changes have caused variations in the biogeochemistry of trace elements in ecosystems, as revealed for instance by natural records from sources as diverse as peat bog sequences [Brännvall et al, 1997;Shotyk et al, 1998;Martinez-Cortizas et al, 2002], lake sediments [Renberg et al, 1994;Camarero et al, 1998], tree rings [Baes and McLaughlin, 1984], and coral formations [David, 2003].…”

“…Here, retention in the terrestrial part may be comparatively low with respect to lowland catch-ments, because a large proportion of the catchment's area is covered by bare rock, soils are thin, and vegetation is scarce. This has lead for instance to the buildup of high concentrations of several trace elements in Pyrenean lake sediments [Camarero et al, 1998;Camarero, 2003], at a level which may be of ecotoxicological relevance.…”

A New Analytic Model to Identify Lead Pollution Sources in Soil Based on Lead Fingerprint

“…Eades [16], Bird [17][18][19], Ferrand [20], and Miller [21] studied lead pollution sources in the aquatic environment. Chiaradia [22,23], Camarero [24], Álvarez-Iglesias [25], and Luo [26] presented detailed analyses about the lead sources in soil and sediments with the Gobeil's model. Kylander [27], Lima [28], and Anderson [29] carried out some similar research using the Gobeil's model in the field of geology and mineral resources.…”