scholarly journals The occurrence of the new zooplankton species in the Lena river delta

2016 ◽  
Vol 320 (4) ◽  
pp. 473-487
Author(s):  
E.N. Abramova ◽  
I.A. Zhulay
Keyword(s):  
Local Population ◽  
Spring Tide ◽  
Passive Dispersal ◽  
Zooplankton Species ◽  
Local Fauna ◽  
Lena River ◽  
Water Ecosystems ◽  
Sida Crystallina ◽  
Lena River Delta ◽  
Observation Period

The Lena River impact on the water bodies of its catchment area increases in connection of climate warming. During spring floods the river water enters the numerous floodplain water basins, further promotes the passive dispersal of their fauna in the northern direction. The occurrences of new (for the local fauna) zooplankton species repeatedly documented in the lakes on Samoylov Island in the south part of the Lena Delta over the last 15 years. Seven “invasive species” belong to Cladocera, four to Copepoda and one species of Rotifera. Some cladocerans –Sida crystallina (O.F. Muller, 1776), Limnosida frontosa (Sars, 1862), Diaphanasoma brachyurum (Lievin, 1848) and Polyphemus pediculus (Linnaeus, 1761) – several times appeared and disappeared in the floodplain aquatic habitats on Samoilovsky Island during the observation period. Simocephalus vetulus (O.F. Muller, 1776) found conditions here to be favorable and formed the local population in the floodplain pools. Acroperus harpae (Baird, 1834) and Holopedium gibberum Zaddach, 1855 started to settle from low floodplain in neighboring water ecosystems of the first delta terrace with a height of 10–16 m. The spread of resting stages of zooplankton are likely to occur with the participation of waterfowl. In years with extremely high spring tide, the expansion of species, not typical for the area, was of a catastrophic nature. A massive invasion of certain species, for example Holopedium gibberum Zaddach, 1855, can cause a rapid restructuring of the lake biocoenosis and disturb the ecological balance in it, resulting in parasitic epizootic.

scholarly journals Geomorphological structure and neotectonics of the Lena delta

2019 ◽  
Vol 65 (2) ◽  
pp. 186-200
Author(s):  
D. Y. Bolshiyanov ◽  
A. O. Aksenov ◽  
A. S. Makarov ◽  
E. I. Lazareva ◽  
S. A. Pravkin ◽  
...  
Keyword(s):  
Late Pleistocene ◽  
Flow Direction ◽  
Radiocarbon Dates ◽  
Lena River ◽  
Speed Difference ◽  
Main Flow Direction ◽  
Lena River Delta ◽  
Tectonic Movements ◽  
Lena Delta ◽  
Observation Period

New data about geomorphological structure and neotectonic movements of the Lena Delta is presented. Thet are based on results of the Russian-German expeditions Lena-2013, Lena-2014, Lena-2015 and Lena-2018 and include geomorphological profiling with high quality satellite instruments and a number of radiocarbon dates on the Sobo-Sise, Kurungnakh, Jangylakh-Sis and Khardang-Sise islands. These islands consist of the Late Pleistocene Ice Complex (IC) remnants eroded by river and sea, and the first terrace of the Delta, which adjoins the remnants. The first terrace started to form 8,000 years ago in the western part of the Delta and was finally formed in the last millennium in the eastern part of the Delta. From the previous works, it is known that the western part of the Delta is higher than the eastern part. In our work, we explain it by the eneven movements of the Earth’s crust in this region. The aim of the paper is to study the quantitative characteristics of the tectonic movements in the Lena River Delta. For this purpose we present the geomorphological schemes and descriptions of the islands mentioned and compare the terraces heights in the different parts of the Delta. In the Late Pleistocene, according to the heights of the IC remnants, the western part of the Delta rose 1 mm per year faster than its eastern part. In the Holocene the speed difference increased to approximately 2 mm per year, which is shown by the terrace surface’s altitude. The amplitude between the western and eastern parts of this surface is about 4 m. Finally, according to 60-years observation period of the water level in the Laptev Sea, the modern speed difference of the western and eastern parts movement in the Lena Delta is 2 mm per year. As a result, we can observe changes in the main flow direction in the Delta channels from the Olenekskaya branch at the beginning of Holocene to the Bykovskaya branch today.

Short-term climate and vegetation dynamics in Lena River Delta (northern Yakutia, Eastern Siberia) during early Eocene

Palaeoworld ◽  
2021 ◽  
Author(s):  
Olesya V. Bondarenko ◽  
Nadezhda I. Blokhina ◽  
Tatiyana A. Evstigneeva ◽  
Torsten Utescher
Keyword(s):  
Vegetation Dynamics ◽  
River Delta ◽  
Early Eocene ◽  
Eastern Siberia ◽  
Short Term ◽  
Lena River ◽  
Lena River Delta

The Rock Magnetic Portrait of the Devonian Section of Stolb Island (Lena River Delta)

2021 ◽  
Vol 501 (1) ◽  
pp. 906-911
Author(s):  
D. V. Metelkin ◽  
A. I. Chernova ◽  
V. A. Vernikovsky ◽  
N. E. Mikhaltsov ◽  
V. V. Abashev
Keyword(s):  
River Delta ◽  
Lena River ◽  
Lena River Delta

scholarly journals Sentinel-1 SAR Interferometry for Surface Deformation Monitoring in Low-Land Permafrost Areas

2018 ◽  
Vol 10 (9) ◽  
pp. 1360 ◽  
Author(s):  
Tazio Strozzi ◽  
Sofia Antonova ◽  
Frank Günther ◽  
Eva Mätzler ◽  
Gonçalo Vieira ◽  
...  
Keyword(s):  
Time Series ◽  
Surface Displacement ◽  
Deformation Monitoring ◽  
In Situ Measurements ◽  
River Delta ◽  
Sar Interferometry ◽  
The Arctic ◽  
Lena River ◽  
Lena River Delta

Low-land permafrost areas are subject to intense freeze-thaw cycles and characterized by remarkable surface displacement. We used Sentinel-1 SAR interferometry (InSAR) in order to analyse the summer surface displacement over four spots in the Arctic and Antarctica since 2015. Choosing floodplain or outcrop areas as the reference for the InSAR relative deformation measurements, we found maximum subsidence of about 3 to 10 cm during the thawing season with generally high spatial variability. Sentinel-1 time-series of interferograms with 6–12 day time intervals highlight that subsidence is often occurring rather quickly within roughly one month in early summer. Intercomparison of summer subsidence from Sentinel-1 in 2017 with TerraSAR-X in 2013 over part of the Lena River Delta (Russia) shows a high spatial agreement between both SAR systems. A comparison with in-situ measurements for the summer of 2014 over the Lena River Delta indicates a pronounced downward movement of several centimetres in both cases but does not reveal a spatial correspondence between InSAR and local in-situ measurements. For the reconstruction of longer time-series of deformation, yearly Sentinel-1 interferograms from the end of the summer were considered. However, in order to infer an effective subsidence of the surface through melting of excess ice layers over multi-annual scales with Sentinel-1, a longer observation time period is necessary.

scholarly journals Lena River Delta formation during the Holocene

2014 ◽  
Vol 11 (3) ◽  
pp. 4085-4122 ◽  
Author(s):  
D. Bolshiyanov ◽  
A. Makarov ◽  
L. Savelieva
Keyword(s):  
Sea Water ◽  
River Delta ◽  
The Arctic ◽  
Laptev Sea ◽  
Lena River ◽  
Sea Levels ◽  
Marine Terraces ◽  
Delta Formation ◽  
Carbon Reservoir ◽  
Lena River Delta

Abstract. The Lena River Delta, the largest delta of the Arctic Ocean, differs from other deltas because it consists mainly of organomineral sediments, commonly called peat, that contain a huge organic carbon reservoir. The analysis of Delta sediment radiocarbon ages showed that they could not have formed as peat during floodplain bogging, but accumulated when Laptev Sea water level was high and green mosses and sedges grew and were deposited on the surface of flooded marshes. The Lena River Delta formed as organomineral masses and layered sediments accumulated during transgressive phases when sea level rose. In regressive phases, the islands composed of these sediments and other, more ancient islands were eroded. Each new sea transgression led to further accumulation of layered sediments. As a result of alternating transgressive and regressive phases the first alluvial-marine terrace formed, consisting of geological bodies of different ages. Determining the formation age of different areas of the first terrace and other marine terraces on the coast allowed the periods of increasing (8–6 Ka, 4.5–4 Ka, 2.5–1.5 Ka, 0.4–0.2 Ka) and decreasing (5 Ka, 3 Ka, 0.5 Ka) Laptev Sea levels to be distinguished in the Lena Delta area.

scholarly journals Dynamics of the relief and sesmotectonic activity of the modern structures in the delta of the river lena

2019 ◽  
pp. 62-77
Author(s):  
L. P. Imaeva ◽  
G. S. Gusev ◽  
V. S. Imaev
Keyword(s):  
Transition Zone ◽  
North American ◽  
Active Faults ◽  
River Delta ◽  
The Arctic ◽  
Main Element ◽  
Dominant Factor ◽  
Lena River ◽  
Lithospheric Plates ◽  
Lena River Delta

This paper presents seismogeodynamic analysis of modern structures located in the Lena river delta. These structures are key elements in the tectonic evolution of the shelf–continent transition zone in the Arctic segment of the boundary between the Eurasian and North American lithospheric plates. The geological structure of the Lena river delta is predetermined by the junction of the ancient Siberian platform and the Mesozoic Laptev Sea plate. These two large geoblocks of the crust, which differ in age, are separated by a fragment of the Kharaulakh segment of the Verkhoyansk fold system. In our study aimed to reveal regularities in seismotectonic destruction of the crust, we analyzed the geological and geophysical data on the crustal structure, active faults, modern structural plan, dynamic characteristics of the modern relief, and hydrological features characterizing of the flow redistribution in the Lena riverbed. A system of active faults identified in the Lena river delta shows a contrasting kinematic plan of the junction zone of the main geostructures. According to the analysis results, shear faulting is a dominant factor of impact on the morphologic features and seismogeodynamic activation of the modern structures. A regional right-lateral strike-slip fault of the sublatitudinal strike is traced as a major structural boundary that cuts the Lena river delta into several geodynamic segments. Seismotectonic destruction of the crust in the segments differs in types (transpression, transtension and compression). The above-mentioned fault is not only the main element of the kinematic plan of the newest structures in the Lena river delta – it controls the general structural pattern and seismotectonic parameters of active fault zones in the entire northern sector of the Verkhoyansk marginal suture. The seismogeodynamic analysis results obtained in our study provide a reliable basis for estimating potential seismic hazard of the modern structures in the Lena river delta and updating the available seismic zoning maps of the shelf–continent transition zone in the Arctic segment of the boundary between the Eurasian and North American lithospheric plates.

scholarly journals Organic carbon and total nitrogen stocks in soils of the Lena River Delta

2012 ◽  
Vol 9 (12) ◽  
pp. 17263-17311 ◽  
Author(s):  
S. Zubrzycki ◽  
L. Kutzbach ◽  
G. Grosse ◽  
A. Desyatkin ◽  
E.-M. Pfeiffer
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Active Layer ◽  
River Delta ◽  
River Terrace ◽  
Total N ◽  
Lena River ◽  
Carbon Mass ◽  
Organic Carbon Pool ◽  
Lena River Delta

Abstract. The Lena River Delta, which is the largest delta in the Arctic, extends over an area of 32 000 km2 and likely holds more than half of the entire soil organic carbon mass stored in the seven major deltas in the northern permafrost regions. The geomorphic units of the Lena River Delta which were formed by true deltaic sedimentation processes are a Holocene river terrace and the active floodplains. Their mean soil organic carbon stocks for the upper 1 m of soils were estimated at 29 kg m−2 ± 10 kg m−2 and at 14 kg m−2 ± 7 kg m−2, respectively. For the depth of 1 m, the total soil organic carbon pool of the Holocene river terrace was estimated at 121 Tg ± 43 Tg, and the soil organic carbon pool of the active floodplains was estimated at 120 Tg ± 66 Tg. The mass of soil organic carbon stored within the observed seasonally thawed active layer was estimated at about 127 Tg assuming an average maximum active layer depth of 50 cm. The soil organic carbon mass which is stored in the perennially frozen ground below 50 cm soil depth, which is excluded from intense biogeochemical exchange with the atmosphere, was estimated at 113 Tg. The mean nitrogen (N) stocks for the upper 1 m of soils were estimated at 1.2 kg m−2 ± 0.4 kg m−2 for the Holocene river terrace and at 0.9 kg m−2 ± 0.4 kg m−2 for the active floodplain levels, respectively. For the depth of 1 m, the total N pool of the river terrace was estimated at 4.8 Tg ± 1.5 Tg, and the total N pool of the floodplains was estimated at 7.7 Tg ± 3.6 Tg. Considering the projections for deepening of the seasonally thawed active layer up to 120 cm in the Lena River Delta region within the 21st century, these large carbon and nitrogen stocks could become increasingly available for decomposition and mineralization processes.

scholarly journals Trace metal distribution in pristine permafrost-affected soils of the Lena River Delta and its Hinterland, Northern Siberia, Russia

2013 ◽  
Vol 10 (2) ◽  
pp. 2205-2244 ◽  
Author(s):  
I. Antcibor ◽  
S. Zubrzycki ◽  
A. Eschenbach ◽  
L. Kutzbach ◽  
D. Bol'shiyanov ◽  
...  
Keyword(s):  
Trace Elements ◽  
Organic Matter ◽  
Trace Metal ◽  
Climatic Changes ◽  
River Delta ◽  
Metal Distribution ◽  
Background Concentrations ◽  
Lena River ◽  
Trace Metal Distribution ◽  
Lena River Delta

Abstract. Soils are an important compartment of ecosystems and have the ability to immobilize chemicals preventing their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since the Arctic ecosystems are considered to be very sensitive to climatic changes as well as to chemical contamination. This study characterizes background levels of trace metals in permafrost-affected soils of the Lena River Delta and its hinterland in northern Siberia (73.5° N–69.5° N) representing a remote region far from evident anthropogenic trace metal sources. Investigations on total element contents of iron (Fe), arsenic (As), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), lead (Pb), cadmium (Cd), cobalt (Co) and mercury (Hg) in different soil types developed in different geological parent materials have been carried out. The highest concentrations of the majority of the measured elements were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex) in the Lena River Delta region. Correlation analyses of trace metal concentrations and soil chemical and physical properties at a Holocene estuarine terrace and two modern floodplain levels in the southern-central Lena River Delta (Samoylov Island) showed that the main factors controlling the trace metal distribution in these soils are organic matter content, soil texture and contents of iron and manganese-oxides. Principal Component Analysis (PCA) revealed that soil oxides play a significant role in trace metal distribution in both top and bottom horizons. Occurrence of organic matter contributes to Cd binding in top soils and Cu binding in bottom horizons. Observed ranges of the background concentrations of the majority of trace elements were similar to background levels reported for other pristine arctic areas and did not exceed mean global background concentrations examined for the continental crust as well as for the world's soils.

Sign in / Sign up

Export Citation Format

Share Document