A Method for Semiquantitative Spectrographic Analysis of Plant Ash for Use in Biogeochemical and Environmental Studies

Abstract

A visual comparison method for semiquantitative spectrographic analysis of plant ash by dc arc technique has been applied to a wide variety of plant material. A split slit technique utilizing a Hartmann diaphragm and step filter assemblage enables the simultaneous recording of volatile elements from a short burn at 100% transmission and less volatile elements from a total energy burn at 15% transmission from the same electrode charge. Volatile elements, e.g., Ag, As, Bi, etc., are thus detected at low concentrations without the necessity of a separate analysis. Standards in a plant ash base are prepared in progressively lower concentrations from spectrographically pure powders in ranges applicable to most plants. Results are reported as six possible logarithmically spaced intervals per order of magnitude. Results show the repeatability to be within one reporting interval of the standards at the 68% confidence level and within two reporting intervals of the standards at the 95% confidence level. The over-all speed of the method suggests an application to large numbers of samples, and the analysis of more than 800 samples per man-month attests to the value of this method in reconnaissance studies.

A modification of the U.S. Geological Survey one-sixth order semiquantitative spectrographic method for the analysis of geologic materials that improves limits of determination of some volatile to moderately volatile elements

“…Comrelative standard deviations (RSD) in table 4. The monly acceptable RSDs for the semiquantitative RSDs o~~ained range in magnitude from 0 to 77 emission spectrographic method range from 10 to (Mosier, 1972). Of the 10 RSDs greater precision because of the poor background-to-line than 30 percent, 5 can be attributed to analyses ratios on the upper end of the spectrum where the of nickel and cobalt.…”

Digital release of stream-sediment, heavy-mineral-concentrate, soil, and other geochemical data collected in the Nabesna 1 degree x 3 degrees Quadrangle, Alaska

“…The radiation of each magnetic concentrate was reported as percent equivalent uranium and the lower limit of determination is 0.003 percent (Pan and others, 1980). The ashed spruce needles were analyzed by a semiquantitative, directcurrent arc emission spectrographic method developed by Mosier (1972) for the analysis of plant ash.…”

Geochemical exploration techniques based on distribution of selected elements in rocks, soils, and plants, Vekol porphyry copper deposit area, Pinal County, Arizona

“…The vegetation samples were analyzed for 35 elements by a six-step semiquantitative emission spectrographic method (Mosier, 1972) (100), and Zr (10). These samples were also analyzed for Cu (1), Mo, 3 and Zn (5) by atomic absorption spectrophotometry (Ward and others, 1969;Nakagawa and others, 1975).…”