Eiliv Steinnes

Use of mosses (Hylocomium splendens and Pleurozium schreberi) as biomonitors of heavy metal deposition: From relative to absolute deposition values

Concentrations of 48 elements in the ground growing mosses Hylocomium splendens and Pleurozium schreberi have been compared with wet deposition data for the same elements at 13 Norwegian sites. Significant positive correlations were found for V, Fe, Co, As, Y, Mo, Cd, Sb, Ce, Sm, Er, Tl and Pb in Hylocomium splendens, and for Mg, V, Fe, Co, As, Se, Y, Mo, Cd, Sb, Tl and Pb in Pleurozium schreberi. Regression equations for transforming moss concentration data to absolute deposition rates have been calculated for those of the above elements which are of interest from a pollution point of view. The concentration levels of Li, Be, Mg, Ca, Zn, Ge, As, Se, Sr, Y, Zr, Sn, Cs, Ba, La, Ce, Pr, Nd, Sm, Ho, Yb, Hf, Ta and U were similar in the two moss species. Hylocomium splendens had highest concentrations of Cr, Fe, Co, Ni, Cu, Ga, Nb, Mo, Sb, Eu, Gd, Tb, Dy, Er, Tm, Lu, W, Tl, Pb and Th, whereas V, Mn, Rb and Cd were highest in Pleurozium schreberi. No variations were observed in the concentrations of the studied elements during the sampling season.

Mosses as biomonitors of atmospheric heavy metal deposition: Spatial patterns and temporal trends in Europe

In recent decades, mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals. Since 1990, the European moss survey has been repeated at five-yearly intervals. Although spatial patterns were metal-specific, in 2005 the lowest concentrations of metals in mosses were generally found in Scandinavia, the Baltic States and northern parts of the UK; the highest concentrations were generally found in Belgium and south-eastern Europe. The recent decline in emission and subsequent deposition of heavy metals across Europe has resulted in a decrease in the heavy metal concentration in mosses for the majority of metals. Since 1990, the concentration in mosses has declined the most for arsenic, cadmium, iron, lead and vanadium (52-72%), followed by copper, nickel and zinc (20-30%), with no significant reduction being observed for mercury (12% since 1995) and chromium (2%). However, temporal trends were country-specific with sometimes increases being found.

A critical evaluation of the use of naturally growing moss to monitor the deposition of atmospheric metals

Abstract Mosses have been used extensively to monitor atmospheric deposition of heavy metals and other trace constituents. In this paper, evidence from multi-element moss surveys is used to discuss the feasibility of this technique and to critically evaluate factors that may lead to misinterpretation of results. Two aspects receive particular attention: (1) calibration against precipitation data to allow transformation of element concentrations in moss to deposition rates and (2) contribution to the elemental composition of the moss from sources other than air pollution, such as marine influence, windblown soil dust, and uptake from soil via higher plants and subsequent transfer to mosses. Specific problems with the use of mosses as biomonitors in the Arctic are also discussed.

Large scale multi-element survey of atmospheric deposition using naturally growing moss as biomonitor

Abstract Data for 26 elements from a nationwide survey in Norway using the moss Hylocomium splendens as a biomonitor are used to illustrate the feasibility of this technique for multi-element studies of airborne trace elements from local point sources, transboundary air pollution, and natural cycling processes. Contributions from non-atmospheric sources such as windblown soil dust and leaching from vascular plants are identified and discussed. Long range atmospheric transport appears to strongly dominate the deposition of several pollutant trace elements in Norway.

Moss (Hylocomium splendens) used as biomonitor of atmospheric trace element deposition: Estimation of uptake efficiencies

Concentrations of Na, Mg, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Rb, Sr, Mo, Cd, Sb, Ba, La, Pb and Bi in Hylocomium splendens were compared with bulk deposition measurements of these elements at six background stations in Norway. Long-range transported elements (V, Cu, Zn, As, Mo, Cd, Sb, Pb and Bi) showed generally significant correlations between moss and wet deposition, and uptake efficiencies relative to that of Pb were estimated to be: V, 40–55%; Cu, 50%; Zn, 35%; As, 10–25%; Mo, 40–60%; Cd, 50–65%; Sb, 35–55%; Bi, 30–40%. The range apparent for some elements is attributed to competition with sea-salt cations in coastal areas. V, Cu, Zn and possibly Mo showed general background levels in the moss, which may be due to essential functions of these or contribution from sources other than atmospheric deposition.

Atmospheric trace element deposition: Principal component analysis of ICP-MS data from moss samples

Data from a Norwegian survey on atmospheric deposition, including 33 elements in 495 moss samples collected in 1990, are presented. The biomonitor moss used was Hylocomium splendens, and the analyses were carried out by ICP-MS. Principal component analysis is used to identify possible sources of the elements determined in the mosses. Dominant factors represent long-range atmospheric transported elements (Bi, Pb, Sb, Mo, Cd, V, As, Zn, Tl, Hg, Ga), windblown mineral particles (Y, La, Al, Li, U, Th, Ga, Fe, V, Cr), local emission sources (Ni, Cu, Co, and As; Zn, Cd, and Hg; Fe, Cr, and Al), transport from the marine environment (Mg, B, Na, Sr, Ca), and contribution from higher plants (Cs, Rb, Ba, Mn). Comparison of the results with similar surveys from 1977 and 1985 show a decreasing contribution of most long-range transported elements to southern Norway.

Relationships between organic matter, black carbon and persistent organic pollutants in European background soils: Implications for sources and environmental fate.

Black carbon (BC) and total organic carbon (TOC) contents of UK and Norwegian background soils were determined and their relationships with persistent organic pollutants (HCB, PAHs, PCBs, co-planar PCBs, PBDEs and PCDD/Fs) investigated by correlation and regression analyses, to assess their roles in influencing compound partitioning/retention in soils. The 52 soils used were high in TOC (range 54-460 mg/g (mean 256)), while BC only constituted 0.24-1.8% (0.88%) of the TOC. TOC was strongly correlated (p<0.001) with HCB, PCBs, co-PCBs and PBDEs, but less so with PCDD/Fs (p<0.05) and PAHs. TOC explained variability in soil content, as follows: HCB, 80%; PCBs, 44%; co-PCBs, 40%; PBDEs, 27%. BC also gave statistically significant correlations with PBDEs (p<0.001), co-PCBs (p<0.01) and PCBs, HCB, PCDD/F (p<0.05); TOC and BC were correlated with each other (p<0.01). Inferences are made about possible combustion-derived sources, atmospheric transport and air-surface exchange processes for these compounds.

Conifer needles as biomonitors of atmospheric heavy metal deposition: comparison with mosses and precipitation, role of the canopy.

Concentrations of seven elements (As, Cd, Cr, Mn, Pb, V, Zn) in mosses (Hylocomium splendens, Pleurozium schreberi, Eurhynchium angustirete) and needles of Norway spruce (Picea abies) and juniper (Juniperus communis) were determined at 48 sites in Lithuania. Conifer needles consistently showed many times lower concentrations than mosses collected at the same site. Correlations between heavy-metal concentrations in needles and mosses indicated that accumulation processes may be similar, but mosses appear to be clearly preferable as biomonitors of atmospheric deposition because of their higher elemental concentrations and more quantitative reflection of deposition rates. Precipitation in the open field and under the canopy was investigated at two stations with respect to the same metals. The canopy was shown to retain a considerable part of lead, whereas elements such as Zn and Mn were enriched in precipitation under the canopy. Study of metal concentrations in moss growing, respectively, below and outside the canopy showed that none of so studied elements was significantly retained by the canopy. Most of the metals (Cu, Fe, Zn, Cr, Ni, V) were leached from the canopy to a smaller or greater extent.

Atmospheric deposition of trace elements in Norway: Temporal and spatial trends studied by moss analysis

The atmospheric deposition of sixteen trace elements, as inferred by their concentration in moss samples collected in 1985 from 500 sites in Norway, is compared with data from a similar survey in 1977. The deposition patterns of V, Zn, As, Se, Cd, Sb, and Pb are substantially influenced by long-range transport from other parts of Europe, but a general decline is evident from 1977 to 1985, most strongly for Pb. For Cr, Fe, Co, Ni, and Cu the deposition patterns are largely determined by contributions from point sources within Norway and on the Kola peninsula close to the Russian/ Norwegian border. The moss data for Br, I, and partly Se reflect airborne supply from the marine environment, whereas Al and Sc serve as indicators of contributions from soil dust. Contributions to the trace element concentrations in moss from sources other than atmospheric deposition are identified and discussed.

Evidence of large scale heavy-metal contamination of natural surface soils in Norway from long-range atmospheric transport

Abstract Results from a nationwide survey of natural surface soils show several heavy metals to be present in substantially higher concentrations in southernmost Norway than in areas farther north. Mean values in this region are as follows (corresponding values from the far north in parentheses): Pb, 111.3 ppm (8.7); Zn, 84.1 ppm (34.6); Cu, 13.5 ppm (8.7); As, 5.9 ppm (1.1); Sb, 2.4 ppm (0.22); Se, 2.0 ppm (0.23); Cd, 1.38 ppm (0.18). The concentrations of most metals decrease regularly along a northerly gradient. Comparison with data from other investigations in Norway regarding air pollution with heavy metals and levels of metals in different soil horizons strongly suggest that long-range transport of metals from other parts of Europe is the main reason for the excess accumulation of metals in the southern topsoils. Only in the case of Cu was this source found to be of minor importance. Deposition from metal smelters within Norway and in bordering areas of Russia are shown to cause elevated levels locally of copper and zinc in particular. High relative levels of Se in coastal areas at all latitudes are assumed to be derived from airborne transport of Se originating from biogenic processes in the ocean.