Geochemical background

The global geochemical background and enormous industrial environmental pollution have increased, thus, there are all the bases to speak about the beginning of biogeochemical formation development which has a direct influence on the ecological system condition in general as well as on the population health. 

In order to assess natural soil geochemical background concentrations, samples were collected from various soil horizons and discrete depth intervals from hand-dug pits. A total of 72 sites were sampled during the 2007 and 2008 field seasons yielding an average density of approximately 1 site per 800 km2 that is double the nominal density of a site per 1600 km2 for the NASGLP. Samples were collected from the surface layer (0 to 5... 

KEYWORDS soil geochemistry, low-density geochemical mapping, geochemical background, continental-scale geochemical mapping, soil... 

Of the 30 lakes that were cored 9 reached geochemical background concentrations and had current concentrations and/or fluxes that are decreasing to present. Five additional lakes that did not reach geochemical background were included for comparison to current wet deposition. Linear models of recovery were estimated on the most recent decreasing trend of concentration and/or flux and by ignoring episodic or short term increases in fluxes or concentrations (Fig. 1). 

There are only about a dozen published studies on Se isotopes and only two on Cr isotopes. This chapter summarizes what has been learned thus far, and almost all of this work concentrates on aqueous reactions at earth surface temperatures. It also attempts to provide some geochemical background and reviews some relevant points from the sulfur isotope literature, which provides insight into the isotopic systematics of Se and Cr. 

Evaluation of Geochemical Background at Regional and Local Scales by Fractal Filtering Technique ... 

In this chapter, the application of multifractal inverse distance weighted (MIDW) interpolation method and a fractal filtering technique, named spatial and spectral analysis or simply (S-A) method (Cheng, 2003), will be illustrated to evaluate geochemical background at the regional and local scale. For this purpose, two case studies will be discussed for two different Italian areas ... 

Albanese, S., Cicchella, D., De Vivo, B., and Lima, A. (2006). Geochemical background and baseline values of toxic elements in stream sediments of Campania region (Italy). J. Geochem. Explor. 93, 21-34. doi 10.1016/j.gexplo.2006.07.006. 

Definition of Geochemical Background and Baseline at an Urban Scale 155... 

Lima, A. (2008). Evaluation of geochemical background at regional and local scales by fractal filtering technique Case studies in selected Italian areas. In Environmental geochemistry Site characterization, Data analysis, Case histories (B. De Vivo, H. E. Belkin, and A. Lima, eds.). Elsevier (this volume). 

The utilization of gamma spectrometry for the quantitative determination of low level activity radionuclides in the natural environment is limited because the influence of the natural geochemical background is very strong, but the technique is often used in the study of airborne radioactivity [6, 7]. Low-level gamma spectrometry is used principally to determine the activity of nuclides such as Co, Cs, and Pb (Fig. 15.1). 

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