Geodatabase and WebGIS project for long-term permafrost monitoring at the Vaskiny Dachi Research Station, Yamal, Russia

The research station Vaskiny Dachi (VD) in central Yamal, Western Siberia was established in 1988. Continuous monitoring of the permafrost state is conducted since 25 years, which allows collecting a large amount of data related to permafrost state and environment of this region. To store and visualise the geospatial data, containing our knowledge of the research area and research topic, we created a geodatabase (GDB) to operatively process different types of geospatial data. The produced GDB contains so far 11 vector feature datasets and raster data in the same coordinate system. The vector data represent: 1) bathymetry; 2) social-economic objects; 3) field data; 4) geomorphology; 5) hydrography; 6) landscapes; 7) permafrost; 8) snow; 9) topography; 10) vegetation; 11) long-term measurement grids and transects (Circumpolar Active Layer Monitoring (CALM) transect, CALM measurement grid). All these feature datasets contain 60 feature classes of spatial data in total. Some of the geodata layers are directly linked to data bases of field data. The raster data contain 37 layers, including a digital ele vation model with derivatives, a map of snow distribution for the key site, ba thymetric maps and other maps of different scale. Moreover, the key area is a site for international research projects and the ongoing exchange of the data is supported by the VD GDB. Geographical Information System (GIS) allows collecting, storing and processing geospatial data from different sources in a wide range of types and formats. WebGIS platforms allow displaying the geospatial data for different users, giving the impression of the general pro cesses on the certain geographic area. Also, we use the WebGIS service to publish the data and to make it available for the larger community. This paper is an overview on the permafrost studies at the VD research station, the GDB for permafrost monitoring as well as the established Yamal WebGIS project

Гидрологические и гидрохимические исследования в дельте р. Лены весной 2015 и 2016 гг.

The results of hydrological and hydrochemical research of on bodies of water: ducts and lakes of the delta of the Lena River are reported here. Studies were performed during the 2015/16 summer (July-August) and winter (April) expeditionary seasons. The present work also introduces the results of field hydrochemical analyzes made immediately after sampling. The values of hydrochemical and hydrophysical indicators of ducts and lakes such as electrical conductivity, pH, permanganate oxidability, concentration of dissolved organic carbon, water color and absorption of colored organic matter were received. This obtained values supplemented significantly the available information on the delta water bodies in winter.Приведены результаты выполненных во время экспедиционных сезонов 2015–2016 гг. в летний (июль–август) и зимний (апрель) гидрологических и гидрохимических исследований на водных объектах — протоках и озерах дельты реки Лены. В работе представлены также результаты гидрохимических анализов, выполненных непосредственно в поле, сразу после отбора проб. Получены величины таких гидрохимических и гидрофизических показателей воды проток и озер, как электропроводность, водородный показатель рН, перманганатная окисляемость, концентрация растворенного органического углерода, цветность воды и абсорбция окрашенного растворенного органического вещества (CDOM), что существенно дополнило имеющиеся сведения о водоемах дельты в зимний период

Sediment-water interaction as an important factor of Arctic lake thermic regime

Research of polar lakes helps to obtain a new in information about limnic process in Polar Regions. It is well known - that these areas are most sensitive to climate change, and therefore even a small shift of the important parameters in aquatic environments can play a huge role for water ecosystems. The thermic regime of polar lakes has its own peculiarities. The water temperature variability in polar lakes usually ranges between 0 and 18 °C , the icecover thickness can reach up to 2 m. The freeze-up usually occurs in the first month of autumn, the breaking up of ice starts beginning of June. Current studies present the particularities of the thermokarst lakes and their thermic regime. The thermal regime was modelled using the thermohydrodynamic model “Flake” developed by Russian – German research team (www.lakemodel.net). Input data for this model are meteorological characteristics as well as lake morphometric measurements. Except climatic parameters what else is the thermic regime of lakes affected by? In our opinion, the heat turnover in the lacustrine sediments of the lake is one of the important processes that can give an additional thermic information. Lacustrine sediments represent a specific bottom “sediment chuck” between lake water body and a depression. Sediment properties such as thickness, humidity, grain-size, organic content and geochemical composition, significantly determine the physical characteristics that influence the lacustrine thermal regime. The thickness of the lacustrine bottom sediment is one of the important characteristics for lake thermal regime modeling, especially in the lakes of the Arctic permafrost regions . This parameter is included in the aforementioned thermodynamic model. Numerical experiments were conducted to test the impact of sediment thickness on the thermal regime. Thickness of the lacustrine sediments were varied from 1 m to 5 m. Modeled results show that the dynamics of the thermic fluxes were similar for sediments with thicknesses of 3 m and 5 m. The maximum positive heat flux was calculated for a thickness of 3 m. The highest negative thermic flux was calculated for a sediment thickness of 1 m. In deep reservoirs, bottom sediments significantly slow down the freezing of the reservoir, since heat accumulates during the summer period. Other physical characteristics of bottom sediments also affect the thermal regime of lakes. For example, wet bottom sediments warm slower because of their low heat capacity. The destruction of organic matter in the water also influences the thermal regime. Heat flow from the organic matter decomposition in sediments, can be quite significant. In the framework of this study, the mechanisms heat flow in lacustrine bottom sediments are analyzed and their parameterization in thermic modeling tested

Relationships between colored dissolved organic matter (CDOM), dissolved organic carbon (DOC) and dissolved mineral substances in different surface waters of the Lena River delta

In order to understand the influence of surrounding catchment characteristics on the CDOM concentration different types of surface waters in the Lena river delta region were investigated regarding their geochemical composition. The Lena River Delta consists of three geomorphological main terraces that differ in their relief, hydrological and cryolithological characteristics, which possibly influences the content of dissolved substances in their associated water bodies and in the neighboring river branches. During summer seasons of 2013-2014 water samples were collected from river branches as well as from lakes and melt-water streams on the first and the third main terraces and analyzed them for concentrations of colored dissolved organic matter (CDOM), dissolved organic carbon (DOC), and main and trace elements (Na, K, Mg, Ca, HCO3, F, Cl, SO4, Fe, Si, Sr). This type of research was carried out for surface waters in the Lena delta region for the first time. Statistical analysis revealed several correlations between CDOM, DOC and mineral ions. For example, R-squared (the coefficient of determination) for CDOM and Cl and for CDOM and Na in Lena River branches were 0.52 and 0.51, respectively. Correlation between CDOM and F was also found for melt-water streams from the Ice Complex (third terrace) (R-squared = 0.5). Analysis of the relationship between CDOM and DOC showed strong correlation of these parameters for lakes (R-squared = 0.98) and lower correlation for river branches (R- squared = 0.48). In streams formed by the thawing of Ice Complex deposits on the third terrace was found the highest values of CDOM and DOC, but a correlation between them was not observed. A clear dependency was found out between CDOM and DOC correlation and the location of lakes on different terraces with specific permafrost conditions. A stronger correlation was observed for the lakes located on the third terrace (Ice Complex) compared to lakes located on the first terrace (Samoylov Island). Usually, lakes on the first terrace get flooded by river waters during spring, whereas lakes of the third terrace are not affected by river water inflow and have more stable conditions. The Lena delta branches are influenced by differing surrounding conditions, therefore CDOM and DOC concentrations change during summer season and did not show strong correlations

Vulnerability of Polar lakes according to investigation of Yamal peninsula, the Lena River delta, and East Antarctica oases water objects

During last 10 years investigations on Polar region lakes have been done that allow compare changing in their regimes with previous studying a half century ago. For analysis of lakes vulnerability/stability three mark regions have been chosen: The Lena River delta, Yamal peninsula and East Antarctic oases. Mark parts of Arctic and Antarctic give some very similar information about lacustrine ecosystem but in other processes different. Our investigation of lacustrine sediment cores show quite high self-cleaning of Arctic lakes according to analysis of a cations exchange capacity between near-bottom water and up layer of a core. Intensive natural eutrophication and lake succession stages replacement are available. Against a background stable glacial lakes in Antarctic there are “active” Arctic thermokarst and alas lakes. In Antarctic drying oases areas have been noticed. As a result, reduction of lakes amount as well as increasing of catchments without outflow were observed. In contrast to Antarctic oases deglaciation water system in Arctic become humidity. So, quantity of small lakes rises and lake outflow upwards. Therefore, there are two main reasons of lake ecosystem features non-conformity. One of them is a climate change, in general, and its different evidence, from another side - drying and humidification in Antarctic and Arctic correspondingly, for instance. Sometimes understanding of possibility of lakes features changes is a complicated fact. Furthermore, composition of separate components of ecosystem parts is unequal of a character of a new changed system. Lake vulnerability of both Polar Regions could be the same against the differences of their parts. Using for further ecosystem progress prediction the non-additive parameters like vulnerability/stability is more correct, consequently. The last point of view is Polar lakes is more open to environmental change, mostly to insolation and biogenic elements income, than to anthropogenic impact from Polar stations in these regions