LOESSFEST'09 | Aug. 31st – Sept. 3rd, 2009 |Novi Sad-Serbia
Highly Resolved Color Indices Recorded at Stari Slankamen Loess-Paleosol Sequence (Vojvodina, Serbia)
Basarin, B.1, Machalett, B.2, Milojković, N.1, Marković, S.B.1, Lukić, T.1,
Vasiljević, Dj. A.1
1Chair of Physical Geography, Faculty of Sciences, University of Novi Sad, Serbia
2Humboldt-University of Berlin, Department of Geography, Unter den Linden 6, D-10099 Berlin, Germany
Loess-paleosol sequences in the Vojvodina region (Serbia), located in the confluence area of the rivers Danube, Sava and Tisza, are thought to be among the oldest and most complete Pleistocene terrestrial paleoclimatic records in Europe (Marković et al., 2008).
Stari Slankamen exposure is located in the eastern part of the Srem Loess Plateau, on the right bank of Danube river, near by the river mouth of the Tisza into the Danube. The geographical coordinates of the site under the study are 45º7’58” φN and 20º18’44” λE. It is thought to be a unique archive of Pleistocene climate variability, characterized by considerable high sedimentation rates during Middle and Late Pleistocene.
Wet and dry colors were determined using Munsell soil color chart. In order to present the change of color of the loess and interstratified paleosols on a curve throughout the profile, the colors in Munsell notation were quantified in RGB color system. For each wet and dry color the RGB values were obtained, thus providing a unique way of showing theone of the most striking features of loess paleosol sequence on a curve. Munsell colorswere also converted in L*a*b* color space for calculating the redness, yellowness and lightness of the exposed sequence.
Rubification and melanization represent common soil development indices. Rubification and melanization indices were calculated following Harden (1982), using spread sheet developed by Taylor (1988) and Vidić and Lobnik (1997).
Calculated soil development indices show increase with depth and time. This trend corresponds well with other investigated exposures in Euroasia (e.g. Vidić et al., 2004, Marković et al., 2009).
Highest values are obtained in basal red clay complex and VS 5, which indicates that during the formation of these pedocomplexes conditions were different then those when younger steppic soils were formed.
Laboratory measurements indicate that under relatively dry and warm soils and sediments such as the soils of the Mediterranean region hematite formation is enhanced (Torrent et al., 1982). Hematite formation is intensified under warm, alternating wet and dry climatic conditions. However, temperatures and precipitation play an important role. Low temperatures in the winter months will cause the goethite formation over hematite, but on the other hand increasing winter temperatures and precipitation will enhance hematite evolution (Buggle et al., 2008, Cornell and Schwertmann, 2003). Calculated indices show gradual paleoclimatic transition from sub-Mediterranean to dry continental climate in this part of Europe. This transition occurred during the periods of steppic soil formation, probably during the development of VS 4 (Buggle et al.,2008). The reason for this conclusion is the rubification values which start to decrease in this part of the investigated profile.
Presented paleopedological indices imply that during Pleistocene paleoclimatic conditions changed from semi humid subtropical to relatively dry steppic environments. Similar paleoclimatic trend has been observed at other Serbian loess- paleosol sequences (Marković et al., 2009), as well as, other equivalent Eurasian loess-paleosol records (e.g. Ding et al., 2002).