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Baseline element concentrations are given for Spanish moss (Tillandsia usneoides), loblolly pine (Pinus taeda), and associated soils. Baseline and variability data for ash, Al, Ba, C, Ca, Cd, Ce, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Sr, Th, Ti, V, Y, and Zn are reported; however, not all variables are reported for all media because, in some media, certain elements were below the analytical detection limit. Spatial variation in element concentration among and within 0.5 km grid cells are given for each of the media. In general, only a few elements in Spanish moss showed statistically significant landscape patterns, whereas several elements in loblolly pine and in soils exhibited differences among sampling grids. Significant differences in the concentration of three elements in Spanish moss and eight elements (including total S) in loblolly pine were observed between two sampling dates (November and June); however, the absolute amount of these differences was small. Except for perhaps Ni and Pb concentrations in Spanish moss, element levels in all sample media exhibited ranges that indicate natural rather than anthropogenic additions of trace elements.

Recent investigations on the Kenai Peninsula had two major objectives: (1) to establish elemental baseline concentrations ranges for native vegetation and soils; and, (2) to determine the sampling density required for preparing stable regional geochemical maps for various elements in native plants and soils. These objectives were accomplished using an unbalanced, nested analysis-of-variance (ANOVA) barbell sampling design. Hylocomium splendens (Hedw.) BSG (feather moss, whole plant), Picea glauca (Moench) Voss (white spruce, twigs and needles), and soil horizons (02 and C) were collected and analyzed for major and trace total element concentrations. Using geometric means and geometric deviations, expected baseline ranges for elements were calculated. Results of the ANOVA show that intensive soil or plant sampling is needed to reliably map the geochemistry of the area, due to large local variability. For example, producing reliable element maps of feather moss using a 50 km cell (at 95% probability) would require sampling densities of from 4 samples per cell for Al, Co, Fe, La, Li, and V, to more than 15 samples per cell for Cu, Pb, Se, and Zn.

Samples of C horizons representing three soil orders and 17 series were collected from 77 locations in an area likely to be affected by energy-related developments. In addition, six samples each of topsoil and spoil were collected from a rehabilitated area of the San Juan mine. All samples were analyzed for 50 variables, including measurements of total, DTPA-extractable, exchangeable, and water-soluble element content. Q-mode factor analysis indicated that a three-factor model explained >90% of the variation in the 50 variables, even though many more than three taxonomic groups were represented. The three extreme types of samples were characterized by their physical properties as sandy soils, soils high in silt clay, and spoil material. Soils with common taxonomic properties did not necessarily have similar chemical properties. Samples most closely associated with each of the three theoretical factor compositions were subjected to R-mode factor analysis to reduce the 50 variables to a more manageable number of master variables (R-mode factors), each showing associations of variables independent from the other factors, R-mode factor analysis indicated that variable associations differed for each group of samples identified by Q-mode factor analysis. Therefore, although different samples may contain similar amounts of some elements, the elements maymore » be in different forms and associated with different constituents for each group of samples. Such differences will affect the suitability of these materials for use in mined-land rehabilitation.« less

The utility of DTPA (0.005M, pH 7.3) and EDTA (0.01M, pH 7.0) extractants for measuring the availability of Cu, Fe, Mn, and Zn from uncultivated A- and C-soil horizons to western wheatgrass (Agropyron smithii Rydb.), silver sagebrush (Artemisia cana Pursh), and above-ground biomass was assessed at 21 geochemically diverse sites in the northern Great Plains. Positive relationships between the extractable or the total concentration of these elements in soils to concentrations in plants, as measured by multiple regression, were limited. A-horizon DTPA-extractable levels of Fe and Mn were significant positive independent variables in the prediction of Fe and Mn levels in wheatgrass. C-horizon DTPA extractable levels of Mn and Zn were significant positive independent variables in the prediction of Mn and Zn sagebrush levels. Multiple regression techniques never gave significant relations between EDTA-extractable element levels and plant element levels; however, strong relations were observed between soil pH and metal concentrations in plants. The relation between plant metal concentration and A-horizon pH was always positive and apparently related to soil levels of metal carbonates. These data indicate that caution should be used in the formulation of regulations for plant available levels of these metals in Great Plains soils based solely on extractable levels.

Regulatory guidelines in several western states require that diethylenetriamine pentaacetic acid (DTPA) be used as an extracting agent for estimating the availability of several elements in natural soils, reclaimed mine soils, and strip mine overburden. Because different sample preparation methods may result in conflicting analytical rresults, the effects of different methods of sample preparation are compared for DTPA extraction of cadmium, cobalt, copper, iron, manganese, nickel, lead, and zinc from soil. Samples of A- and C-horizon soils, with known diverse chemical properties, were collected at 21 localities in unglaciated portions of the Northern Great Plains. Each sample was split into three parts. One part was disaggregated to < 10 mesh; the second was disaggregated and grround to < 100 mesh; and the third was disaggregated and sieved, the < 100 mesh portion being retained. The concentration of elements in the DTPA extracts of the samples prepared in these three ways varied by element and by method of preparation. Consistently, for all methods of sample preparation and in both soil horizons, the effect of sample preparation was not significant for nickel; was significant for iron and manganese; and, for cadmium and cobalt, analytical imprecision invalidated the results. Inconsistent results were obtainedmore » for copper, lead, and zinc either between methods of preparation or between soil horizons. Significant linear equations relating the various methods were obtained for copper, iron, manganese, nickel, lead and zinc, but, because of poor analytical precision, not for cadmium and cobalt.« less

Hypogymnia enteromorpha and Usnea spp. were collected in the Little Bald Hills ultramafic region of Redwood National Park, California, to establish element-concentration norms. Baselines are presented for Ba, Ca, Cu, Mn, Ni, P, Sr, V, and Zn for both lichen species; for Li, Mg, and K for H. enteromorpha; and for Al, Ce, Cr, Co, Fe, Na, and Ti for Usnea. Element concentrations of future collections of this same material can be used to monitor possible air quality changes anticipated from mining activities planned nearby. The variability in the element concentrations was partitioned between geographical distance increments and sample preparation and analysis procedures. In general, most of this variability was found in samples less than a few hundreds of meters apart rather than those at about 1 km apart. Therefore, except for Ba and Co, no large geographical element-concentration trends were observed. Samples of both species contained elevated levels of Ni and Mg, which probably reflect the ultramafic terrain over which they occur.

Plutonium-239 in the fine particulate soil fraction of surface dust is subject to suspension by air currents and is a potential health hazard to humans who may inhale it. This respirable particulate fraction is defined as particles less than or equal to 5 micrometers. The respirable fraction of surface dust was separated by ultrasonic dispersion and a standard water-sedimentation procedure. Plutonium concentration in this fraction of off-site soils located downwind from the Rocky Flats Nuclear Weapons Plant (Jefferson County, Colorado) were as much as 380 times the background concentration. It is prposed that this method of evaluation defines more precisely the potential health hazard from the respirable fraction of plutonium-contaminated soils.

In response to earlier findings or elevated levels of selenium in the Kendrick area, two detailed geochemical surveys were conducted in 1988 to stud y the distribution of selenium in soils (0-1 m depth), and new growth of associated big sagebrush (Artemisia tridentata Nutt.) and alfalfa (Medicago sativa L.). A survey of the native rangeland focused on specific geologic units as sources of selenium; whereas, a gridded survey of the irrigated lands assessed the extent of its mobilization, transport, and concentration. Only three of the approximately 200 soil samples contained total selenium slightly greater than the 3.3 ppm maximum baseline established for soils from the northern Great Plains. In contrast, selenium concentrations in about one-fifth of the big sagebrush samples exceeded the 1.1 ppm maximum baseline established for this species from the West. Selenium tended to be elevated, but not uniformly so, in both soils and sagebrush collected from areas underlain by the Cody Shale of Cretaceous age. Alfalfa from about 15% of the irrigated fields contained selenium in excess of about 4 ppm, levels reported to be potentially hazardous to livestock if fed over prolonged periods. Most of these samples were concentrated in an area of 11 contiguous sections where selenium-enriched surface and drain waters also occurred. The agricultural soils just to the north of this seleniferous area had slightly higher levels of selenium compared to those elsewhere in the irrigated lands. At present, the cause for this displaced anomaly is unclear. Followup sampling in 1989 of two fields where selenium levels in alfalfa collected in 1988 were 25 and 15 ppm yielded samples that contained only 0.2 and 0.7 ppm, respectively. This dramatic and puzzling temporal disparity may be explained by marked differences in weather patterns and irrigation practices for the 2 years. Such a disparity underscores the need to monitor a potentially seleniferous area over an extended period.

Mean concentrations of 35 elements, ash yields, and pH have been estimated for samples of soils and other unconsolidated surficial materials from 266 collection locations throughout Alaska. These background values can be applied to studies of environmental geochemistry and health, wildlife management, and soil-forming processes in cold climates and to computation of element abundances on a regional or worldwide scale. Limited data for an additional eight elements are also presented. The concentration values for 35 elements in 266 samples were plotted on maps by symbols representing classes of concentration frequency distributions. These plotted symbols form patterns that may or may not be possible to interpret but nevertheless show differences that are observable at several geographical scales. The largest pattern is one of generally low concentrations of many elements in materials from arctic and oceanic tundra regions, as contrasted to their often high concentrations in samples from interior and southeastern Alaska. The pattern for sodium is especially pronounced. Intermediate-sized patterns are shown, for example, by the generally high values for magnesium and low values for silicon in the coastal forest region of southeastern Alaska. Many elements occur at low concentrations in samples from the Alaskan peninsula and the Aleutian Islands. Themore » degree of confidence in patterns of element abundance is expected to be in direct proportion to the number of samples included in the area. As the patterns become smaller, the probability increases that the patterns are not reproducible. 42 figures, 3 tables.« less