Diversity of the rodent communities in the Turan Desert region

2006 ◽  
Vol 1 (4) ◽  
pp. 153-161 ◽  
Author(s):  
Valery M. NERONOV ◽  
Ludmila A. KHLYAP ◽  
Andrey A. WARSHAVSKY
Keyword(s):  
Desert Region ◽  
Rodent Communities

An ecological approach to mapping remote creative practices: insights from an Australian Desert region

2021 ◽  
pp. 1-20
Author(s):  
Brydie-Leigh Bartleet ◽  
Sarah Woodland ◽  
Naomi Sunderland ◽  
Sandy O’Sullivan
Keyword(s):  
Ecological Approach ◽  
Desert Region

scholarly journals Groundwater physico-chemical properties and water quality changes in shallow aquifers in arid saline wetlands, Ouargla, Algeria

2021 ◽  
Vol 11 (5) ◽  
Author(s):  
Fethi Medjani ◽  
Mohamed Djidel ◽  
Sofiane Labar ◽  
Louiza Bouchagoura ◽  
Chouaib Rezzag Bara
Keyword(s):  
Water Quality ◽  
Chemical Properties ◽  
High Water ◽  
Quality Changes ◽  
Shallow Aquifers ◽  
Shallow Water Table ◽  
Chemical Mechanisms ◽  
Desert Region ◽  
Physico Chemical ◽  
Hypersaline Water

AbstractShallow aquifers are vulnerable to natural geogenic processes as well as anthropogenic influences, and this is especially apparent in desert regions. Within arid and hyperarid climates, evaporation is a controlling hydrologic process leads to an important increase in the concentration of dissolved minerals of both surface water and groundwater. In groundwater, this increase is not only dependent on shallow water table depth, but also on the hydraulic properties of sediments present within the unsaturated zone of the aquifer itself. The main objective of this research is to investigate possible mechanisms that might influence water quality changes under seasonal conditions in shallow aquifers situated within the Saharan desert region of Algeria. In this work, we focus on observed changes in hydrogeochemical characteristics, and the possible responsible processes. Under arid conditions, high water mineralization results in hypersaline water or brine solution formation within shallow aquifers. Due to active physico-chemical mechanisms such as Na+/Ca2+ ion exchange, the successive precipitation of calcite, gypsum, mirabilite or blœdite and halite is induced. Biological processes were also observed as prevalent; evidenced by large measured variations in CO2 load concentrations. These processes contributed to an inverse relationship between CO2 and O2 concentrations within the shallow aquifers studied.

Spatial non-stationarity effects of driving factors on soil respiration in an arid desert region

CATENA ◽  
2021 ◽  
Vol 207 ◽  
pp. 105617
Author(s):  
Jinlong Wang ◽  
Dexiong Teng ◽  
Xuemin He ◽  
Lu Qin ◽  
Xiaodong Yang ◽  
...  
Keyword(s):  
Soil Respiration ◽  
Driving Factors ◽  
Desert Region ◽  
Arid Desert

LITHOBIOTOPES OF THE NEMEGT GOBI BASIN

2021 ◽  
Author(s):  
Tomasz Jerzykiewicz ◽  
Philip J. Currie ◽  
Federico Fanti ◽  
Jerzy Lefeld
Keyword(s):  
Upper Cretaceous ◽  
Alluvial Plain ◽  
Gobi Desert ◽  
Large Species ◽  
Physical Processes ◽  
Desert Region ◽  
Ephemeral Channels ◽  
Temporal Succession ◽  
Asymmetric Distributions ◽  
Rich Fauna

Three distinct but overlapping dinosaur-dominated faunas characterize the Upper Cretaceous Djadokhta, Baruungoyot and Nemegt formations of the Nemegt Basin of Mongolia. Documented faunal differences cannot be explained easily by temporal succession, but can be understood in the light of physical processes controlling life, death, and burial of taxa. The stratigraphy of the Gobi Desert region records tectonically driven geometries, clearly documenting preservational processes different than those acting in most other dinosaur-dominated beds worldwide. Small, asymmetric tectonic grabens were filled with Upper Cretaceous, dinosaur bearing deposits showing asymmetric distributions of facies, here termed Lithobiotopes. The water-lain fluvial and alluvial plain facies of the Nemegt Lithobiotope supported and preserved a fauna dominated by gigantic dinosaurs, but had a preservational bias against smaller animals. The Nemegt passed laterally into interdune facies of the Baruungoyot Lithobiotope, which represented a hostile environment for large species, but preserved smaller animals. This in turn passed laterally into the aeolianite facies of the Djadokhta Lithobiotope, which is characterized by remains of small dinosaurs and a rich fauna of other animals. The Nemegt Gobi Basin can be visualized as an oasis with a central pond supplied with water from ephemeral channels and surrounded by a semi-arid alluvial plain and dune fields.

Simulations on Hydrodynamic Coefficients of Stationary Cactus-Shaped Cylinders at a Low Reynolds Number

2018 ◽  
Author(s):  
J. Wang ◽  
C. Shi ◽  
Y. Liu ◽  
X. Bao
Keyword(s):  
Reynolds Number ◽  
Low Reynolds Number ◽  
Bending Moment ◽  
Hydrodynamic Coefficients ◽  
Rotational Angle ◽  
Desert Region ◽  
Helical Strakes ◽  
Wind Velocities ◽  
Low Reynolds ◽  
Very High

Flexible cylinders, such as marine risers, often experience sustained vortex-induced vibration (VIV). Both helical strakes and fairings are demonstrated to be effective in suppressing VIV, while, helical strakes result in large drag, which increases the rotational angle and bending moment at the riser hang-off location and, fairings are cumbersome in term of storage, installation and maintenance. This study was inspired by the giant Saguaro Cacti which grow in desert region. Saguaro Cacti have shallow root system, but can grow up to fifty feet in height and can withstand very high wind velocities. In this study, numerical simulations of flow past a stationary cactus-shaped cylinder are performed in two-dimensional field at a low Reynolds number of 200. The hydrodynamic coefficients and the vortex-shedding patterns of a cactus-shaped cylinder are compared with those of a circular cylinder. In addition, a set of two cactus-shaped cylinders of tandem arrangement are also studied to investigate the effects of wake. Results showed that a cactus-shaped cylinder can reduce the drag, lift, and Strouhal number, which suggests its potential as an alternative technology to suppress VIV of a riser.

Sign in / Sign up

Export Citation Format

Share Document