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Geochemical background in soils: a linear process domain? An example from Istria (Croatia) 总被引：1，自引：1，他引：0
Definition of geochemical background in exploration and environmental geochemistry has always been regarded as contingent
upon scale and investigated locality but mostly under assumption that hosts of processes that produce the data more or less
conform individually to Gaussian law of “central tendencies”. Recently, understanding of pedogenesis as synergetic process
being characterized by non-linear dynamics renders thermodynamic approach directly applicable in assessment of geochemical
thresholds, with concepts of linearity and normality set alongside in solving the problems of soil geochemistry. Seen from
this perspective the work is an attempt to relate conceptual fundamentals of non-linear dynamical theory to basic statistical
methods in order to elucidate the nature and origins of element subpopulations hidden in the original geochemical data from
the soils of Istrian Peninsula (western Croatia). To this purpose the two major groups of soils were selected for analysis
depending on the type of bedrock as one of the main soil-forming factors. Geochemical data were subjected to the trimming
procedure by which the outliers were removed from the total data collective and attributed to non-linear causes precluding
simple cause-and-effect relationships as the sine qua non of Gaussian distribution. Geochemical background is then defined as the normal range of data of the remaining (trimmed) dataset
indicating the “thermodynamic branch” of the specific soil processes as opposed to outliers being described as dissipative
structures. 相似文献
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The chronostratigraphy of the latest Middle Pleistocene aeolian and alluvial activity on the Island of Hvar,eastern Adriatic,Croatia 
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下载免费PDF全文 Lara Wacha Igor Vlahović Sumiko Tsukamoto Marijan Kovačić Ozren Hasan Davor Pavelić 《Boreas: An International Journal of Quaternary Research》2016,45(1):152-164
Pleistocene aeolian sands and alluvial deposits can frequently be traced along the Mediterranean coast. Such deposits also exist along the eastern Adriatic coast and the nearby islands. Four stratigraphical sections of these deposits were studied on the Island of Hvar with the purpose of establishing a chronological framework of the aeolian–alluvial depositional system, using luminescence dating and magnetic susceptibility stratigraphy. Luminescence dating was applied on coarse‐grained feldspar and quartz grains separated from the sands. Both quartz optically stimulated luminescence (OSL) and feldspar post‐IR infrared stimulated luminescence (pIRIR) age estimates are in good agreement, with values ranging between 167±24 to 120±12 ka (OSL) and 179±18 to 131±18 ka (pIRIR measured at 290 °C) after a fading correction for the pIRIR signal. The results can be clearly correlated to around the end of oxygen isotope stage (OIS) 6 and the beginning of OSI 5, indicating that the aeolian accumulation of sands was a result of the Penultimate Glacial and climate fluctuations at the beginning of the Last Interglacial. Variations in magnetic susceptibility (MS) data can be interpreted alongside these dating results; several stronger peaks detected at the very end of the Penultimate Glacial and the initial stage of the Last Interglacial cycle most probably indicates more intensive pedogenesis resulting from a more favourable climate, probably because of climate changes. Breccias related to major bounding surfaces in association with evidence of soil formation and bioturbation could be the result of more favourable climate conditions and changes during the transition from OIS 6 to OIS 5 (Penultimate Glacial–Last Interglacial). These results are in agreement with similar data from the wider Mediterranean area. 相似文献
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Tamara Markovic Slobodan Miko Sanja Kapelj Renato Buljan Ozren Larva Zoran Peh 《Journal of Geochemical Exploration》2006,88(1-3):124
The Croatian south part of the country is mainly composed of strongly krastified carbonate rocks. Also in this south part of Croatia is lacking of large depressions and poljes with thick covers. Some karst poljes and depressions may have thick covers, like for example the Vransko polje. The Vransko polje is characterised by an intensive agricultural activity. At the centre of the polje is located a karst spring (Turanjsko jezero), which is used for the water supply of the town Biograd and its surroundings. Total metals, nutrients (nitrate, ammonia, phosphate), organic matter content and cation exchange capacity (CEC) were measured in soil samples collected from the polje. Metals and nutrients were also measured in the water samples of channel Kotarka (which is passing through the area) and three springs (Turanjsko jezero, Kakma and Tinj). Measured total concentrations of metals of soil samples were treated by R-cluster multivariate statistical analysis. The result of statistical analysis showed grouping of metals with similar behaviour. Content of metals and nutrients were low in the spring samples but high in the water sample of the channel Kotarka, because the channel drains the water from the surroundings. Although agricultural activity in the Vransko polje is high, there is no high anthropogenic influence on groundwater and soil. They are both of good quality. 相似文献
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