Mixed Helminthosis in Sheep Intestines in Dagestan

The purpose of the research is studying mixed zoonosis of sheep intestines and helminth biodiversity in the altitudinal zonation of Dagestan. Materials and methods. We used materials in our work that were collected in 1985-2018 from sheep (young animals up to 1 year old, 1 to 2 years old, and 3 years old and older) by seasons of the year. 5,000 fecal samples were tested and 180 intestinal dissections were performed. We used the method of complete helminthological dissection of animals and humans per Skrjabin, the method of sequential washing of feces according to Berman-Orlov, the method of cultivation of gastrointestinal Strongylata larvae in a thermostat, and the method of their differentiation according to Shumakovich by shape, number and location of intestinal cells. Results and discussion. In terms of species, representatives of the genera Nematodirus Ransom, 1907, 7 species, Trichostrongylus Loss, 1905, 5 species, Ostertagia Ransom, 1907, 6 species, and Cooperia Ransom, 1907, 4 species prevail in the plain and sub-mountain belts of Dagestan. At the population level, the species Nematodirus, Haemonchus, Trichostrongylus are more often recorded. H. contortus (Rudolphi, 1803), N. spathiger (Railliet, 1896), N. filicollis (Rudolphi, 1802), T. axei (Cobb., 1879), T. capricola (Ransom, 1907), T. colubriformis (Giles, 1829), Cooperia oncophora (Ranson, 1907), C. punctata (Linstov, 1906), Bunostomum trigonocephalum (Railliet, 1902), and Chabertia ovina (Fabricius, 1788) were observed in the mountain belt.

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Topographic evolution of mountain belts controlled by rheology and surface process efficiency

10.5194/egusphere-egu2020-4317 ◽

2020 ◽

Author(s):

Sebastian G. Wolf ◽

Ritske S. Huismans ◽

Jean Braun ◽

Xiaoping Yuan

Keyword(s):

Steady State ◽

Process Efficiency ◽

Surface Process ◽

Tight Coupling ◽

Active Growth ◽

Term Survival ◽

Erosion Rates ◽

Mountain Belt ◽

Tectonically Active ◽

Mountain Belts

It has been a long-standing problem how mountain belts gain and loose topography during their tectonically active growth and inactive decay phase. It is widely recognized that mountain belt topography is generated by crustal shortening, and lowered by river bedrock erosion, linking climate to tectonics. However, it remains enigmatic how to reconcile high erosion rates in active orogens as observed in Taiwan or New Zealand, with long term survival of topography for 100s of Myrs as observed for example in the Uralides and Appalachians. Here we use for the first time a tight coupling between a landscape evolution model (FastScape) with an upper mantle scale tectonic (thermo-mechanical) model to investigate the different stages of mountain belt growth and decay. Using two end-member models, we demonstrate that growing orogens with high erosive power remain small (<200 km), reach steady state between tectonic in- and erosional material eff-flux, and are characterized by transverse valleys. Contrarily, mountain belts with medium to low erosive power will not reach growth steady state, grow wide, and are characterized by longitudinal rivers deflected by active thrusting. However, during growth both types of orogens reach the same height, controlled by rheology and independent of surface process efficiency. Erosional efficiency controls orogenic decay, which is counteracted by regional isostatic rebound. Rheological control of mountain height implies that there is a natural upper limit for the steepness index of rivers on Earth. To compare model results to various natural examples, we quantify the degree of longitudinal flow of modeled rivers with river &#8220;longitudinality&#8221; in several active or recently active orogens on Earth. Application of the river &#8220;longitudinality index&#8221; gives information whether (parts of) an orogen is or was at steady state during orogenic growth.

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Biodiversity of oribatid mites in the ecosystems of Dagestan and their infection with Moniezia sp. procercoids

Russian Journal of Parasitology ◽

10.31016/1998-8435-2021-15-4-36-42 ◽

2021 ◽

Vol 15 (4) ◽

pp. 36-42

Author(s):

M. M. Zubairova ◽

A. M. Atayev ◽

N. T. Karsakov ◽

Z. M. Dzhambulatov ◽

S. T. Atayeva

Keyword(s):

Salt Marshes ◽

Oribatid Mite ◽

Infection Intensity ◽

Oribatid Mites ◽

Altitudinal Zonation ◽

Different Types ◽

Different Seasons ◽

Mountain Belts ◽

River Valleys

The purpose of the research is studying the oribatid mite biodiversity on the Dagestan pastures in terms of altitudinal zonation and their infection with Moniezia sp. procercoids.Materials and methods. Oribatid mites were collected in different seasons of 1990–2020 on different types of pastures of the plain, foothill, and mountain belts of Dagestan. A total of 16,000 specimens of oribatid mites were collected. 120 sets of lamb intestines were dissected. Oribatid mites were collected using the Tulgren funnel. The method of complete helminthological dissection according to K. I. Skrjabin was used in the work.Results and discussion. On low-lying wet pastures of the flat belt, up to 5800 oribatid specimens were recorded per 1 m² with 38.0% prevalence of infection (PI) with moniezia cysticercoids; 675 specimens were collected on the steppe lands with the PI of 12.5%, up to 140 specimens were collected on salt marshes with the PI 0.9%, and 52 specimens were collected in the semi-deserts with the PI 0.4%. In the foothill steppes, 1,300 oribatids specimens were found per 1 m² with their procercoid infeсtion up to 18.0%, 2100 specimens with 16.0% were collected along river valleys, and 120 specimens with the PI of 0.5% on mountain plateaus. Lambs on low-lying wetlands of the lowland belt were infected with Moniezia sp. by 72.0% with the infection intensity (II) of 8-116 specimens, on steppe pastures by 67.5% at the II of 5–36 specimens, on salt marshes by 18.0% with the II of 2–8 specimens, and in semi-deserts by 12.0% with the II of 2–5 specimens. In the foothill steppes, lambs were infected with Moniezia sp. by 68.0% with the II of 9–64 specimens, along river valleys by 69.0% with the II of 11–62 specimens, and on mountain plateaus by 12.0% with the II of 2–4 specimens.

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From Structures to Mountain Belt Dynamics – a global and multidisciplinary perspective

10.5194/egusphere-egu21-2490 ◽

2021 ◽

Author(s):

Christoph von Hagke

Keyword(s):

Multiple Scales ◽

Imaging Techniques ◽

Large Data ◽

Data Sets ◽

Mechanical Heterogeneity ◽

Mountain Belt ◽

Structural Work ◽

Geodynamic Processes ◽

Mountain Belts ◽

Multidisciplinary Perspective

Understanding the formation of mountain belts requires integrating quantitative insights on multiple scales. While this has long been known, it is now possible to enlarge the scales of observation by exploiting global data sets, making use of data sets covering large regions, or including automated data analysis. At the same time the lower limit of observation is pushed farther, and by now structures can be routinely analyzed at the micro- or even nano-scale over large areas making use of digital imaging techniques.In this talk I will present results from a variety of geological settings illustrating the use of large data sets for better understanding of mountain belt dynamics. To this end, I will integrate micro-structural work, numerical and analog models, and regional studies of fault geometries and their time evolution constrained by digital field techniques and low-temperature thermochronometry. A particular focus will be laid on the role of mechanical heterogeneity and strain localization through time. It is shown that in some regions geodynamic processes are responsible for local fault geometries, while in others much more local factors such as rheological contrasts of individual layers or even the changes of rheology through time plays a major role. Multiscale studies exploiting digital techniques and including the dimension of time provide an exciting avenue for state of the art and future geological studies.

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The effects of a Meso-Alpine collision event on the tectono-metamorphic evolution of the Peloritani mountain belt (eastern Sicily, southern Italy)

Geological Magazine ◽

10.1017/s0016756817000413 ◽

2017 ◽

Vol 155 (2) ◽

pp. 422-437 ◽

Cited By ~ 2

Author(s):

STEFANO CATALANO ◽

ROSOLINO CIRRINCIONE ◽

PAOLO MAZZOLENI ◽

FRANCESCO PAVANO ◽

ANTONIO PEZZINO ◽

...

Keyword(s):

Southern Italy ◽

Shear Zones ◽

Surface Expression ◽

Accretionary Wedge ◽

Lateral Shear ◽

Metamorphic Overprint ◽

Collision Event ◽

Mountain Belt ◽

Mountain Belts ◽

Positive Tectonic Inversion

AbstractThe Peloritani Mountains, in the southern part of the Calabrian Terranes, southern Italy, have been classically interpreted as the product of the Paleogene brittle deformation of the European continental back-stop of the Neotethyan subduction complex. This reconstruction conflicts with the occurrence of an Alpine metamorphic overprint that affected portions of both the Variscan metamorphic units and part of the Mesozoic sedimentary covers of the mountain belt. New field data, integrated with petrographic, micro- and meso-structural analyses and stratigraphic investigation of the syn-tectonic terrigenous covers, well constrain a Paleogene collision event along the Africa–Nubia convergent margin that caused the exhumation of the Alpine metamorphic units of the Peloritani Mountains. The syn-collisional exhumation was associated with shearing along two major Africa-verging crustal thrusts arising from the positive tectonic inversion of the former European palaeomargin. Early tectonic motions occurred within the mountain belts and produced the exhumation of the external portions of the edifice. Later tectonic motions occurred along the sole-thrust of the entire edifice and caused the definitive exhumation of the entire mountain belt. The whole crustal thrusting lasted for a period ofc. 10 Ma, during the entire Oligocene. The definitive southwestward emplacement of the Peloritani Mountain Belt onto the Neotethyan accretionary wedge was followed by two Late Oligocene – Early Miocene NW–SE-oriented right lateral shear zones, replacing the previous crustal thrust. These two strike-slip belts are interpreted as the surface expression of the deep-seated suture zone between the colliding Africa and Europe continental crusts.

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Erosional response of an actively uplifting mountain belt to cyclic rainfall variations

Earth Surface Dynamics Discussions ◽

10.5194/esurfd-2-971-2014 ◽

2014 ◽

Vol 2 (2) ◽

pp. 971-1004 ◽

Cited By ~ 1

Author(s):

J. Braun ◽

C. Voisin ◽

A. T. Gourlan ◽

C. Chauvel

Keyword(s):

Power Law ◽

Coming Out ◽

Numerical Solutions ◽

Rainfall Variability ◽

Time Lag ◽

Mountain Range ◽

Stream Power ◽

Mountain Belt ◽

Rainfall Variations ◽

Mountain Belts

Abstract. We present an approximate analytical solution to the stream power equation describing the erosion of bedrock in an actively uplifting mountain range subject to periodic variations in precipitation rate. It predicts a time lag between the climate forcing and the erosional response of the system that increases with the forcing period. The predicted variations in the sedimentary flux coming out of the mountain are also scaled with respect to the imposed rainfall variations in a direct proportion to the discharge exponent, m, in the stream power law expression. These findings are confirmed by 1-D and 2-D numerical solutions. We also show that the response of a river channel is independent of its length and thus the size of its catchment area, implying that all actively eroding streams in a mountain belt will constructively contribute to the integrated signal in the sedimentary record. We show that rainfall variability at Milankovitch periods should affect the erosional response of fast uplifting mountain belts such as the Himalayas, Taiwan or the South Island, New Zealand, and predict 1–10 thousand years offsets between forcing and response. We suggest that this theoretical prediction could be used to independently constrain the value of the poorly defined stream power law exponents, and provide an example of how this could be done, using geochemical proxy signals from an ODP borehole in the Bengal Fan.

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Constraining tectonic uplift and advection from the main drainage divide of a mountain belt

Nature Communications ◽

10.1038/s41467-020-20748-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Chuanqi He ◽

Ci-Jian Yang ◽

Jens M. Turowski ◽

Gang Rao ◽

Duna C. Roda-Boluda ◽

...

Keyword(s):

Analytical Solutions ◽

Tectonic Uplift ◽

Horizontal Advection ◽

Migration Direction ◽

Mountain Belt ◽

Southern Taiwan ◽

Mountain Belts ◽

And Migration ◽

Advection Velocity ◽

Northeastern Sicily

AbstractOne of the most conspicuous features of a mountain belt is the main drainage divide. Divide location is influenced by a number of parameters, including tectonic uplift and horizontal advection. Thus, the topography of mountain belts can be used as an archive to extract tectonic information. Here we combine numerical landscape evolution modelling and analytical solutions to demonstrate that mountain asymmetry, determined by the location of the main drainage divide, increases with increasing uplift gradient and advection velocity. Then, we provide a conceptual framework to constrain the present or previous tectonic uplift and advection of a mountain belt from the location and migration direction of its main drainage divide. Furthermore, we apply our model to Wula Shan horst, Northeastern Sicily, and Southern Taiwan.

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Erosional response of an actively uplifting mountain belt to cyclic rainfall variations

Earth Surface Dynamics ◽

10.5194/esurf-3-1-2015 ◽

2015 ◽

Vol 3 (1) ◽

pp. 1-14 ◽

Cited By ~ 20

Author(s):

J. Braun ◽

C. Voisin ◽

A. T. Gourlan ◽

C. Chauvel

Keyword(s):

Power Law ◽

Coming Out ◽

Numerical Solutions ◽

Rainfall Variability ◽

Time Lag ◽

Mountain Range ◽

Stream Power ◽

Mountain Belt ◽

Rainfall Variations ◽

Mountain Belts

Abstract. We present an approximate analytical solution to the stream power equation describing the erosion of bedrock in an actively uplifting mountain range subject to periodic variations in precipitation rate. It predicts a time lag between the climate forcing and the erosional response of the system that increases with the forcing period. The predicted variations in the sedimentary flux coming out of the mountain are also scaled with respect to the imposed rainfall variations in a direct proportion to the discharge exponent, m, in the stream power law expression. These findings are confirmed by 1-D and 2-D numerical solutions. We also show that the response of a river channel is independent of its length and thus the size of its catchment area, implying that all actively eroding streams in a mountain belt will constructively contribute to the integrated signal in the sedimentary record. We show that rainfall variability at Milankovitch periods should affect the erosional response of fast uplifting mountain belts such as the Himalayas, Taiwan or the South Island, New Zealand, and predict 1000 to 10 000-year offsets between forcing and response. We suggest that this theoretical prediction could be used to independently constrain the value of the poorly defined stream power law exponents, and provide an example of how this could be done, using geochemical proxy signals from an ODP borehole in the Bengal Fan.

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