GEOCHEMISTRY OF N1VEO-EOLIAN SEDIMENTS IN THE NORTHERN PART OF WEDEL JARLSBERG LAND, SPITSBERGEN

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1 Andrzej Górniak Institute of Biology Branch Warsaw University in Białystok Józef Wojtanowicz Institute of Earth Sciences Maria Curie-Skłodowska University Lublin, Poland XX Polar Symposium Lublin, 1993 GEOCHEMISTRY OF N1VEO-EOLIAN SEDIMENTS IN THE NORTHERN PART OF WEDEL JARLSBERG LAND, SPITSBERGEN INTRODUCTION Niveo-eolian processes occurring in the circumpolar and temperate zones cause sedimentation of forms or resedimentation of the earlier forms. The intensity of the processes results in significant transformations of soil cover (Jahn 1969, Gerlach 1986, Górniak 1983). Their role in morphogenesis of Spitsbergen area was emphasized many times (Czeppe 1966, Szczypek 1981,1982, Sinkiewicz 1989). The recorded intensity of niveo-eolian processes in this area (Wojtanowicz 1990) points to the potential importance in soil cover formation and creation of favourable habitation conditions with tundra vegetation devolution (Pirożnikow, Górniak in print). Therefore there have been undertaken chemical studies of niveo-eolian forms deposited in the Arctic area in order to determine fully their role in geochemistry and landscape. Sampling methods and a granulometric analysis were described in the earlier papers (Wojtanowicz 1990) and the average share of each fraction is presented in Tab. 1. In the niveo-eolian sediments collected in 1989 during Geographical Expedition IV, Maria Curie-Skłodowska University, Lublin, the total content of elementary macrocomponents was determined (Pirożnikow, Górniak in print) and the analysis of organic carbon fractional composition was made. CHEMICAL COMPOSITION OF SEDIMENTS Niveo-eolian material was significantly differentiated in grain-size distribution which affects chemical composition of sediments. Therefore the obtained results of chemical analyses were made into four basic groups: sands, clay formations, dusts and eolian-sandy formations on eolian terrace. In the studied material the share of dust fraction mm exceeded 25% and based on soil science the studied formations can be defined as dusty. 333

2 Grain-size distribution being a resultant of range and intensity of eolian processes in one of the factors influencing chemical composition of sediments. Chemical composition is also affected by the type of rocks and eluvium undergoing eolian corrasion. In the studied sediments mineral parts were predominant and the organic part content changed from 0.1 to 14.8% in the forms deposited in Calypsostranda periphery, particularly in the part of deflation tundra (Rzętkowska 1987), the organic part exceeded 10%. In the chemical composition of collected sediments Si0 2 was predominant from 65.8% (Calypsobyen) to 85.18% (Reindeers Valley) and on the average it was 76.6% for all samples. The greatest amount of this compound was found in the sandy sediments on the eolian terrace (Tab. II). However, non-eolian sands and clay forms included a much smaller amount of this compound which points to a different mineralogical composition. The second element as far as the content is concerned was calcium (Ca) whose amount changed from 0.01 % in the sediments from Barentsburg to 12.5% in the eolian sediments from Renardbreen. A significant amount of this element was found in sandy and clay sediments (Tab. II). The lover Si0 2 content in the sandy forms and great Ca content indicate to the presence of calcite in the sand fraction. It is also an evidence of short transport of the form which originates from detrital minerals or from the rocks in the initial stage of physical weathering. In longer transport or advanced weathering processes calcite grains are dissolved. Calcite is rarely found in the fraction finer than thick dust included in postglacial formations (Górniak, unpublished data). Iron and aluminium occurring in sediments show smaller differentiation and their higher contents were found in the sediments of increased amount of organic matter. With slightly advanced soil processes (Melke et. al. 1990), biogeneous accumulation is amain process leading to greater amount of Fe and Al in sediments. Magnesium amount in the sediments was 0.9% on the average, whereas the smallest amounts were found in dusty forms. The other analyzed elements were found in trace amounts among which those of phosphours were the smallest. Its maximum concentration was found in sandy forms and the lowest in dusty ones. (Tab. II). There should be noted a small quantity of sodium in spite of significant part of aerosols of marine origin in the coastal zone. The analyses of contemporary niveo-eolian forms from Svalbard made it possible to compare them with Pleistocene loess forms from Lublin and Przemyśl regions (according to Borowiec, 1970) and contemporary niveo-eolian sediments from Lublin Upland (Górniak 1983) (Tab. III). As follows from the comparison, the niveo-eolian sediments have similar chemical composition. The only differences are found in potassium. The calcium content is similar and the higher contents of iron and aluminium in loesses probably result from the character of indigeneous rock aluvium. The amount of phosphorus is similar. Based on the data of niveo-eolian processes intensity (Wojtanowicz 1990) it 334

3 was calculated that accumulation of aluminium and calcium whit the material on the snow was about 8 g/m 2, iron 1.5 and Mg, К, P was 0.7 g, 0.1 g and 20 mg/m 2 respectively. Accumulation of biophylic elements; potassium and phosphorus did not exceed 0.5 of the resources of forms assimilable in these soils (Melke et al. 1980). The values show some role of these sediments after melting and sedimentation on the rocks of Heckla Hoek series in forming vascular plants habitats. COMPOSITION OF SEDIMENT ORGANIC SUBSTANCE The organic carbon content in sediments was differentiated as well as the soil of this region (Szerszeń 1974, Melke et. al. 1990, Pirożnikow, Górniak in print). In the studied sediments the organic carbon contents changed from 0.53 to 5.6% and the average was 2.81% (Tab. IV). These values are comparable with those given by Jahn (1969) and higher than the data by Górniak (1983) for Lublin Upland. The greates part almost 46% of carbon constituted the carbon compounds non-extractable by the applied solvents mainly humins and lignins. The similar results were obtained by Szerszeń (1974) while analyzing the soils of Svalbard. The amount of non-active carbon compounds in the niveo-eolian sediments is correlated with the contents of floatable parts. Another group of carbon compounds separated during the analysis were celluloses (extraction by 72% sulphuric acid). These are the remains of unhumificated mosses, lichens and other plants whose greatest part in organic carbon was found in dusty forms of distant transport. Assuming the average accumulation of material calculated by Wojtanowicz (1990), deposits of organic carbon with sediments were 2.02 g/m 2 which constitutes 0.15% of carbon resources in the soil of this region according to the data by Melke et al. (1990). Another group of carbon compounds found in the niveo-eolian sediments are specific soil compounds-humus acids of the average part of 22% organic carbon (Tab. IV). These compounds are found in the studied forms mainly in a free from 51 % to 81 % of the sum of acids in the sediment. In clay and dusty forms of higer floatable part content, the amount of forms connected with sesquioxides and mineral ones significantly increases. Among humus acids, fulvic acids are predominant and their amount is almost twice as great as that of humin acids. It should be noted that in the fraction of free humus compounds, the amount of humin acids is much greater than in the form complexed with mineral parts. These values are close to the data by Szerszeń (1974) from the soils in this area and also the results of studies carried out by Aleksandrova (1951) in Caucasus. The data show that in the case of sedimentation, the humus compounds included in sediments can become a stimulatior of biological activity of cover formations. As follows from many investigations humus acids and particulary fulvic ones are 335

4 destructive both for primary minerals and the whole rock promoting together with mikroorganisms secondary mineral formations (Kowda 1984). As follows from calculations eolian accumulation of humus compounds reaches 780 mg C/m 2. Bitumines constitute the smallest part in organic carbon though their amount in the sandy forms on eolian terrace was high 22% of the carbon sediment. The presence of these compounds in sediments is due to fragments of moss and lichen remains deflated from soils as well as with intense development of algae on snow in the final stage of snow melting. Algae can contain up to 30% of compounds extractable with ethanol and benzene. Summing up the presented results of analyses of niveo-eolian sediments from Svalbard are geochemically differentiated due to the range of deflation processes. The eolian forms deposited on snow are similar to loess sediments in some regions of Poland. The composition of organic substances found in deposits on the snow in this region shows the quality of this substance in the soils of the studied area. REFERENCES Aleksandrova I. V., 1951: Processy gumusoobrazovanija v niekotorych gornykh primitivnykh pochvach. Pochvovedenije, 10. Borowiec J., 1970: Porównanie składu i właściwości lessów występujących na obszarze Polski. Annales UMCS, sect. В, 25, Czeppe Z., 1966: Przebieg głównych procesów morfogenetycznych w południowo-zachodnim Sptisbergenie. Zesz. Nauk. Uniw. Jagiell. CXXVII, Prace Geograficzne, z. 13, Kraków, Gerlach Т., 1986: Erozja wietrzna i jej udział w degradacji gleb w Karpatach. Folia Geogr. Ser. Geographica-Physica, XVIII, Górniak A., 1983: Natężenie procesów niveo-eolicznych na glebach lessowych Działów Grabowieckich w styczniu 1982 r. Prace SKNG UMCS, Lublin, Jahn A., 1969: Niveo-eoliczne procesy w Sudetach i ich działanie na glebę. Probl. Zagosp. Ziem. Górskich, 5(18), Kowda W. A., 1984: Podstawy nauki o glebach. PWRiL, Warszawa, 896 p. Melke J., Chodorowski /., Uziak S., 1990: Soil formation and soil properties in the areas of Lyellstranda, Dyrstad and Logne in the region of Bellsund (West Spitsbergen). Pol. J. Soil Sri. XXIII, Pirożnikow E., Górniak A., Zmiany pokrywy roślinnej i właściwości gleb w sukcesji pierwotnej na przedpolu Werenskioldbreen. Pol. Polar Res. (in print). Sinkiewicz M., 1989: Skutki geomorfologiczne działalności procesów eolicznych na Ziemi Oscara II (Spitsbergen). XVI Sympozjum Polarne. Toruń, Szczypek Т., 1981: Przejawy działalności wiatru na wybrzeżu morskim pod Rasstupet (Sorkappland-Spitsbergen). Studia et dissertationes, Geographia, Szczypek Т., 1982: Działalność eoliczna w rejonie Zatoki Gas (południowy Spitsbergen). Prace Nauk. UŚ, 543, Szerszeń L., 1974: Wpływ czynników bioklimatycznych na procesy zachodzące w glebach Sudetów i Spitsbergenu. Rocz. Glebozn., 25, Wojtanowicz J., 1990: Eolian processes and their intensity in the northern part of Wedel Jarlsberg Land, Spitsbergen. Wyprawy Geograficzne na Spitsbergen, Lublin,

5 Adresses of the authors: dr Andrzej Górniak, Institute of Biology Branch Warsaw University in Białystok, Świerkowa 20b, Białystok, Poland prof, dr hab. Józef Wojtanowicz, Institute of Earth Sciences UMCS, Akademicka 19, Lublin, Poland GEOCHEMIA OSADÓW N1VEO-EOLICZNYCH W PÓŁNOCNEJ CZĘŚCI ZIEMI WEDELA JARLSBERGA, SPITSBERGEN Streszczenie Analizowano zróżnicowane pod względem litologicznym współczesne osady niveo-eoliczne na Spitsbergenie; były to osady piaszczyste, gliniaste i pylaste (Tab. I). W składzie chemicznym (Tab. II) dominuje SiO z o zawartości 65,8-85,2%; średnio 76,6% i Ca o zawartości 0,01-12,5%; średnio 4,27%. Z porównania z plejstoceńskimi lessami Polski południowej lessami lubelskimi i przemyskimi wynika, że analizowane osady niveo-eoliczne mają zbliżony do lessów skład chemiczny. Jedyne większe różnice dotyczą potasu (K), którego w utworach niveoeolicznych Spitsbergenu jest zdecydowanie mniej (Tab. III). Przeanalizowano także skład substancji organicznej w utworach niveo-eolicznych (tab. IV). Zawartość С org. waha się w przedziale 0,5-5,6%; średnia wartość 2,8%. Największy udział w zawartości węgli organicznych mają huminy i ligniny, natomiast stosunkowo mały bituminy. Wydzielono grupę kwasów humusowych, które stanowią 22% węgla organicznego. Wśród kwasów humusowych dominują kwasy fulwowe, a ich udział jest blisko dwukrotnie większy niż kwasów huminowych. Skład substancji organicznej w utworach niveo-eolicznych odzwierciedla jakość tej substancji w gjebach badanego obszaru. Praca wykonana w ramach realizacji projektu badawczego (Grant KBN) nr

6 Tab. I. Grain-size distribution of niveo-eolian forms Niveo- Clay Eolian Eolian,sandy eolian forms dusts forms on eolian sadds terrace Number of samples mm 0,1 0,8 2,0 17, ,6 1,6 0,1 5,8 1-0,3 23,1 19,0 2,1 11,4 0,5-0,25 14,6 9,0 1,0 6,6 0,25-0,10 26,9 16,3 6,1 27,7 0,10-0,05 16,0 24,3 39,8 17,2 0,05-0,01 8,6 21,9 34,6 11,1 0,01-0,005 1,6 3,1 8,2 2,4 0,005 2,5 4,0 6,1 O.i. Mz 2,08 3,27 4,75 1,84 J Sk, 1,75 0,14 2,25-0,04 1,69 0,14 2,55-0,20 КС 1,06 0,87 1,53 0,95 Tab. II. Chemical composition of niveo-eolian forms in % s.m Kind Number of form of samples Si0 2 Al Fa Ca Mg К Na P i'uveo-eolian sands 8 74,67 3,61 0,93 5,68 0, ,02 0,0^3 Clay forms 1 73,16 2,40 0,93 4,28 0,96 0,06 0,01 0,010 Eolian dusts 2 81,56 3,53 1,29 0,41 0,58 0,09 0,02 0,007 Eolian,sandy forms on eolian terrace 1 85,18 3,13 0,30 0,75 0,95 0,03 0,01 0,011 Average 12 76,57 3,46 0,98 4,27 0,90 0,06 0,02 0,

7 Tab. Ш. Comparison of chemical composition of loesses and niveo-eolian materials from Sptisbergen (% by weight) Compound Loesses Niveo-eolian in Lublin region in Przemyśl region materials Si0 2 71,7 70,8 76,6 re 1,27 1,96 0,98 A1 3,96 4,60 3,46 Ca 4,83 3, Mg 0,84 0,86 0,90 X 1,51 2,39 0,06 p 0,02 0,02 0,02 Tab. IV. Fractional composition of organic carbon of niveo-eolian forms (% org. C) Kind of form Niveo-eolian sands Clay forms Eolian dtists Solian sandy forms on eolian terrace Number of samples % org.с 2,90 3,28 2,69 1 > 1 5 Bitumens 8,45. 10,0 4,31 22,48 Humus acids including fulvic acids humin acids С kh : С kfc 25,85 16,20 9,65 0,60 14,60 9,37 5,23 0,56 24,92 18,31 6,61 0,36 51,87 16,27 35,60 2,18 Chemicelluloses and celluloses 15,65 16,86 41,93 15,20 Humins j 50,05 i 58,46 28,84 10,55 339