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The surge-type Uisu glacier and its forefield in the Tajik part of Eastern Pamir are described. To this end, 1977–2019 Landsat satellite imagery, the DEM, and a high-resolution orthophotomap were used, and detailed geomorphological mapping was carried out. The results show that the present-day position of the terminus of the studied glacier results from a surge that occurred before 1947. Currently, the glacier is losing mass. However, despite the visible characteristics of its thawing, the extent of the terminal zone has remained stable for several decades. Outside the glacier, there are no glacial landforms. This indicates that advances of surging glaciers may not create any surge-diagnostic features in their forefields. On the other hand, the genesis and interactions of landforms can reveal glacier surge, even in the absence of terminal and lateral glacial landforms.

Fire has considerable impact on vegetation and organic soils properties. As we observed that the differences between vegetation of burnt and unburnt areas on the rich fen are visible 11 years after the fire, we assumed that the post-fire changes are long lasting, yet limited exclusively to the burnt areas. In order to check this hypothesis we studied spatial differentiation of physical and chemical properties of soils, and productivity capacities of burnt and unburnt areas in the fen in Biebrza National Park. We took soil samples from the neighboring burnt and unburnt areas, from the depth of 0–30 cm and 30–50 cm. We analyzed 21 parameters of the soils including: pH, ash content, moisture, bulk density, exchangeable K, Na, Ca, available P, N-NH4+, N-NO3−, total N, C, K, Na, Ca, Mg, Fe, P; and calculated C:N, C:P ratios. Surface layer of the burnt soils differed significantly from the unburnt soils in respect of 17 out of 21 parameters. The most pronounced difference was observed for available phosphorous (on average 6 times higher for the burnt soils). The differences in the deeper layer were mostly insignificant. The burnt areas were also characterized by twofold higher plant productivity than recorded for the unburnt areas. The influence of fire on peaty soils was long lasting but mostly limited to the surface layer of the soils. In the case of particular soil features, the post-fire differences were modified by advanced muck formation (moorshing) processes in the unburnt areas. Since the fire led to long lasting increase of fertility, the recovery of fen vegetation is unlikely.

Small, astatic ponds are important features of post-glacial landscape, which support heterogeneity and biodiversity of agricultural areas. In the presented research we explored differences in hydrochemistry and plant cover of 20 small ponds located in Northeastern Poland, characterized by diverse age and developed in differently managed areas. According to our research, though changes in water level are under direct influence of water balance in the catchment, to which belonged the ponds, their hydrochemistry seemed to be shaped by processes at the level lower than the catchment scale. Age of the ponds appeared to be an important factor influencing density and species composition of vegetation developed on the studied ponds.

The article considers the prerequisites for the formation of urbanized agro-production, notes its main advantages and development prospects. The main emphasis is made on intensive urban crop production, which is one of the most dynamically developing areas of city farming. A brief review of the most popular hydroponic systems presented, their specifics are described. We have identified the main vegetable, berry, green and ornamental crops, in the cultivation of which hydroponics technologies are actively used. An important factor in the development of intensive crop production is the introduction of new crops into production. Thus, one of the most perspective directions, in our opinion, is citrus crops. In addition to their highest nutritional value, citrus fruit processing products are widely used in the cosmetic and medical industries. Colossal volume of world production and consumption of citrus fruits has made this crop the most economically important fruit crop in the world. Thus, this article presents statistics on the volume of global production, exports and imports of citrus fruits for 2019. One of the most important consumers of citrus fruits in the world trade is the Russian Federation, but due to climatic conditions, its own production of citrus fruits using classical technologies of ground cultivation is very limited. In this article, the advantages of intensive hydroponics cultivation of citrus crops were hypothesized and a preliminary experiment was conducted. Observation of the experimental plants showed an increase in growth rate relative to their counterparts growing in soil in a winter greenhouse under similar temperature, humidity and light conditions. These preliminary results open wide possibilities for further experiments on selection of cultivars, grafting methods and obtaining productive plants. [ABSTRACT FROM AUTHOR]

The article presents the diagnosis of contamination of light chestnut soils of Volzhsky, Volgograd region with petroleum products and heavy metals using various bioindicators: earthworms of the genus Lumbricus rubbellus and fungus of the genus Botryitis cinerea. The following indicators of bioindication of soil pollution were identified: the survival rate of the earthworms Lumbricus rubbellus, the total microbial number of light chestnut and the mycelium mass of the fungus of the genus Botrytis cinerea. In clay and sandy light chestnut soils that are contaminated with oil and petroleum products, the mortality of earthworms of the genus Lumbricus rubellus was noted on day 7. After 7 days, the spores of the Botrytis cinerea fungus began to grow on the control and light chestnut sandy soil of gas station number 3, and after 14 days -- on other soils. The survival rate of earthworms depends on the quality of petroleum products and does not depend on the granulometric composition of soils. The largest total microbial number of light chestnut soil, estimated by the Botrytis cinerea fungus, is observed in the sandy soil of gas station number 3 (133333 CFU/cm³ of water soil extract), and the smallest -- in the clay soil of gas station number 1 (6773 CFU/cm3 of water soil extract). [ABSTRACT FROM AUTHOR]

To elucidate the dynamics of terrestrial leaf waxes in a high-altitude lake system, we performed compound-specific radiocarbon analysis (CSRA) of long-chain n-alkanes in two sediment core sections from Lake Karakul (Pamirs, Tajikistan) and in surface soil samples from the catchment area. We aimed to answer the question whether the n-alkanes are delivered into the lake sediment with substantial delay due to storage in soils, which may cause a potential bias when used as paleoenvironmental proxies. In the surface soils, the CSRA results reveal an age range of n-alkanes from modern to 2278 ± 155 cal BP. In the two sediment core samples, three of the four n-alkane ages fell on the lower ends of the 1σ-uncertainty ranges of modeled ages of the sediments (based on AMS 14C-TOC and OSL dating results). We conclude that sedimentary leaf waxes represent compounds with intermediate turnover time in soils, for example originating from alluvial plains close to the shores. Overall, the results provide evidence that sedimentary leaf wax compounds in this cold and arid setting are potentially older than the conventional age model indicates, but these findings need to be interpreted in context of the generally large uncertainty ranges of such age models. [ABSTRACT FROM AUTHOR]

Thanks to their unique physical, chemical, and biological properties, raised bogs are considered archives of past hydrological and vegetation changes, which in the case of ombrotrophic bogs may reflect alterations of paleoclimate. Detailed studies on the past transformations of bogs provide researchers with necessary knowledge to anticipate future changes of these ecosystems. The aim of this research was to find a good and easily obtainable paleoenvironmental proxy that can be used in preliminary studies with no need for advanced equipment and extra costs. For our studies three raised bogs were chosen, whose genesis and history have been comprehensively described by other authors according to micro- and macrofossil data. We performed chemical analyses on the samples from the cores taken from the described bogs. Obtained results were compared with accessible data on the bogs' development and underwent statistical analysis. In general, geochemical features of peat presented in this article corresponded well with the accessible micro- and marcofossil data, and content of non-hydrolysable lipids in peat turned out to be the best indicator of water level on the studied bogs. [ABSTRACT FROM AUTHOR]

• The Neolithic Kelteminar settlement existed on lacustrine fine-textured sediments. • The concept of a great lake was rejected in favour of small local lake. • Polygenetic soils allowed reconstructing the environmental changes. • Disappearance of the lake led to abandonment of the area by Neolithic stockbreeders. • Gypsisols are underestimated in soil maps of the area in favour of Calcisols. The Neolithic Kelteminar culture developed in Central Asia mainly along the paleochannels of the Zerafshan delta. However, many settlement sites were identified at approximately 200 m a.s.l without a clear relation to known water bodies. The present study aimed to test the hypothesis on the Neolithic settlement on the lacustrine sediments of a postulated great lake, based on a geomorphological and pedological investigation. This investigation was performed at Ayakagytma "The Site", one of the best documented Kelteminar settlements near the Ayakagytma depression, about 130 km north of Bukhara in the Kyzylkum Desert, Uzbekistan. The investigation was conducted in the catena localised at the transition from the dry-steppe plateau to the bottom of the Ayakagytma Depression. Soil profiles at the archaeological site consist of fine-stratified, fine-textured sediments, free of coarse fragments. The morphology, texture, and geochemistry of the sediments suggest their lacustrine origin and differ substantially from those identified on a high plateau (old, coarse-textured alluvium) and in the depression (stratified, variably textured alluvium and clay-textured regolith, rich in bedrock fragments). The composition of n-alkanes and sterols in the buried A horizons allowed the differentiation between the terrestrial, transitional, and lacustrine origin of biomass and supported the reconstruction of the environmental conditions accompanying the sedimentation of organic matter. The study area has experienced successive climatic and hydrological changes, currently reflected in the unique features of soil sequence starting with relict Gypsisols on the high plateau, Solonchaks (archaeological site in the transitional zone), and Fluvisols and Gleysols in the depression. Favourable conditions for a Neolithic settlement existed along the shoreline of a small lake in the transitional zone between the depression and the plateau. The disappearance of the lake after the destruction of the limestone barrier was the most probable reason for the permanent abandonment of the area by Neolithic stockbreeders. [ABSTRACT FROM AUTHOR]