Record of denudation processes in the sediments of a tundra lake (Petuniabukta, Central Spitsbergen)

On the eastern coast of Petunia Bay there is a complex of tundra lakes at various stages of geosuccession. A characteristic feature is the occurrence of tundra lakes on raised sea terraces. The geoecosystem of raised sea terraces with tundra lakes is clearly separated from the neighboring geoecosystems in terms of geology, lithology, morphology, hydrology and phytosociology. The lowest erosion-accumulation terraces from the middle and younger Holocene range from 5 to 16 m a.s.l. The terraces are composed of marine gravel and rock deposits with a significant content of calcium carbonate and the remains of malacofauna. The research results indicate diverse sources of origin of denudation solutes occurring in coastal lakes. The conducted research contributed to the creation of a model of the functioning of tundra lakes. Mapping and field tests of bedrock sediments were carried out in designated geoecological zones around lakes: sampling of sediments for mechanical and petrographic composition, measurement of humidity, temperature, specific conductivity EC, pH and calcium carbonate content in the soil. In addition, drilling was carried out in the lake sediments and around the lake, based on which the nature and rate of denudation processes were estimated.