Atmospheric lead deposition in an ombrotrophic peat bog of Southern Poland

Poster (2010)

Traces metal inputs in the Misten bog (East Belgium): Level of contamination and spatial variability

Poster (2010)

Environmental changes in two lakes of Northern Patagonia (Chile): A 1000 yr reconstruction based on pollen and charcoal.

Poster (2010)

Multiproxy, multicore palaeoenvironmental study during the last millennium in the Misten peat bog (Hautes Fagnes, East Belgium).

Poster (2010)

Geochemical evidence (C, N and Pb isotopes) of recent anthropogenic impact in south-central Chile from two environmentally distinct lake sediment records

in Journal of Quaternary Science (2010), 25(7), 1100-1112

In this paper, we compare the elemental and isotopic (C, N, Pb) geochemistry of lake sediments from two contrasted environments in south-central Chile. The first lake, Laguna Chica de San Pedro (LCSP), is ... [more ▼]

In this paper, we compare the elemental and isotopic (C, N, Pb) geochemistry of lake sediments from two contrasted environments in south-central Chile. The first lake, Laguna Chica de San Pedro (LCSP), is situated in the urbanised area of the Biobio Region (36°S). The second lake, Lago Puyehue (40° S), is located 400 km to the southeast of LCSP and within an Andean national park. Our aim is to identify environmental impacts associated with increasing industrial activities and land degradation during the last 150 a. In LCSP, shifts in C/N atomic ratios, 13C and 15N from 1915-1937 to the late 1980s are attributed to successive land degradation episodes in the lake watershed. Based on a Pb isotopic mixing model, we estimate that up to 20% of lead in LCSP sediments is supplied from urban atmospheric pollution. By contrast, human impact in the watershed of Lago Puyehue is very limited. We observe no change in organic geochemistry during the last 150 a and lead contamination remains lower than 5%, even during the last decades. Although contamination levels are much higher in LCSP than in Lago Puyehue, a peak in anthropogenic Pb is recorded during the same period (1974-1976) at both sites. This maximum contamination level is consistent with increased industrial activity in the vicinity of Concepción. [less ▲]

Development of lead-210 measurement in peat using polonium extraction. A procedural comparison

in Geochronometria (2010)

Two chemical treatments for lead-210 measurement were compared on the sub-surface samples of a core from an ombrotrophic bog from East Belgium. The classical procedure involves a concentrated acid ... [more ▼]

Two chemical treatments for lead-210 measurement were compared on the sub-surface samples of a core from an ombrotrophic bog from East Belgium. The classical procedure involves a concentrated acid extraction of polonium. However, this treatment represents substantial health risks together with unknowns regarding both the degree of cleanliness and the Po extraction rate, and most importantly, is rather time consuming. We developed here an improved procedure involving an ashing step prior to acid extraction. This allows substantial improvements such as: 1/ the use of a relatively small amount of acid compared to the classical procedure and 2/ the substantial reduction of a total sample digestion time. Measurements of 210Pb concentrations were conducted by alpha spectrometry. Results show a good agreement of unsupported 210Pb activity obtained for both procedures, although some unknowns remain concerning the adsorption of 210Po on the plastic test tube, the volatilization of a small amount of ash, or the absorption of alpha particle at the alpha source surface. This however should not affect the 210Pb measurement as all the samples are spiked prior to ashing (i.e. the recoveries are fully monitored). Through this study, we are suggesting researchers to follow this new procedure in order to increase safety, cleanliness, better recovery and substantial time gain. [less ▲]

Anthropogenic impacts in North Poland over the last 1300 years -- A record of Pb, Zn, Cu, Ni and S in an ombrotrophic peat bog

in Science of the Total Environment (2009)

Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb–Zn ores ... [more ▼]

Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb–Zn ores and coal were the main sources of Pb, other heavy metals and S over Northern Poland up until the industrial revolution. After review of the potential mobility of each element, most of the historical interpretation was based on Pb and Pb isotopes, the other chemical elements (Zn, Cu, Ni, S) being considered secondary indicators of pollution. During the last century, leaded gasoline also contributed to anthropogenic Pb pollution over Poland. Coal and Pb–Zn ores, however, remained important sources of pollution in Eastern European countries during the last 50 years, as demonstrated by a high 206Pb/207Pb ratio (1.153)relative to that of Western Europe (ca. 1.10). The Pb data for the last century were also in good agreement with modelled Pb inventories over Poland and the Baltic region. [less ▲]

Holocene evolution of deep circulation in the North Atlantic constrained by sedimentary radiogenic tracers.

Conference (2009)

Holocene environmental changes in lake sediments from Northern Chilean Patagonia

Poster (2009)

3D anatomy of Heinrich Layer 2.

Poster (2009)