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Salinity is a highly important problem in arid and semi-arid regions. Consequently, the analysis of soil salinity plays a crucial role in environmental sciences. Environmental variables show spatial variability and statistical tools able to analyze and describe the spatial dependence and quantify the scale and intensity of the spatial variation are needed. Moreover, the spatial prediction has special importance for agricultural transformation of the land or for environmental restoration (selection of the most appropriate species adapted to soil salinity). In this paper we propose a methodological framework based on geostatistics to model the spatial dynamics of soil salinity measurements to further analyze the case of a region in southeastern Spain. [ABSTRACT FROM AUTHOR]

Total suspended particulate samples (TSP) were collected and concentrations measured during seventeen months in the vicinity of a ceramic industrial area. A method of fractionating was applied to the samples in order to obtain two fractions corresponding to mineral particulate coming from dust emissions (Upper-F fraction) and to amorphous matter (carbon plus small amounts of S, Ca, Fe, etc) coming mainly from traffic and other combustion processes. Also for TSP samples several element concentrations were measured following two previous treatments: extraction of elements mainly associated with the soluble fraction of the samples (B, Fe, P, As, NO2-, NH4+, Cl-, F) and acid digestion for trace metals and elements mainly associated with the non-soluble fractions of the samples (Fe, As, Cd, Ni, Pb, Zn Ca). Seasonal differences and the influence of meteorological parameters (temperature, relative humidity, pressure and wind conditions) on the air pollution levels, particles as well as ions, were studied. Results show different seasonal and weekly evolution for mineral and amorphous carbonaceous particles because of the different origins in dust emissions or combustion processes respectively, and the different physical properties such as size grain. Of the ions analyzed Fe, Ca and Zn were clearly associated to mineral phases and consequently related to dust emissions, and NO2-, NH4+, P, Cl- were related to amorphous matter coming from combustion. Ni and Cd show lower levels than those reported as guideline values and the source is mainly related to the enrichment of these elements in clay materials. B and As content result in elevated concentrations, with the tendency to increase during cold months. The emission of these elements was associated with vaporization or volatilization during high temperature ceramic processes. The original gaseous state is influenced by temperature. In the winter the content for B and As is higher due to enhanced condensation of gas-phase boron onto particles, while in the summer the increase of air temperature results in elevated evaporation. [ABSTRACT FROM AUTHOR]