scholarly journals Biodiversity of Vegetation around the Mingechevir Reservoir

2021 ◽  
Author(s):  
Novruzov V Vagif ◽  
İsmailova Zilkhumar
Keyword(s):  
High Pressure ◽  
Deep Water ◽  
Vegetation Cover ◽  
Land Reclamation ◽  
Earth Dam ◽  
Anthropogenic Factors ◽  
Green Cover ◽  
Original Vegetation ◽  
Artificial Reservoirs

Mingechevir reservoir is one of the deep-water artificial reservoirs in the territory of Azerbaijani was created on the Kura River in the 50s. Before the construction of the Mingechevir reservoir, 681 species of plants belonging to 74 families and 325 genera were found here. As a result of our research in the valley in 2019-2021, only 154 species were found, belonging to 24 families and 36 genera. As a result of changes during the last 70 years of the hydrographic regime, the influence of edaphic, physical, anthropogenic factors, the original vegetation cover of the Mingechevir Valley has completely changed, and urbanization, land reclamation and other works have further accelerated these changes. If the successions that have begun are not prevented, there may be a risk of destruction of the high-pressure earth dam built in Europe using the leaching method. With the implementation of the proposed phytomeliorative measures, the bare slopes of the reservoir dam can be turned into a “green cover”.

STUDYING OF TERSKO-SULAKSKAYA LOWLAND VEGETATION UNDER THE RESULTS OF GROUND-BASED RESEARCH AND AUTOMATED INTERPRETATION

1970 ◽  
pp. 29-32
Author(s):  
M. I. Dzhalalova ◽  
A. B. Biarslanov ◽  
D. B. Asgerova
Keyword(s):  
Plant Communities ◽  
Satellite Imagery ◽  
Vegetation Cover ◽  
Anthropogenic Impacts ◽  
Species Abundance ◽  
Remote Sensing Data ◽  
Indigenous Communities ◽  
The State ◽  
Anthropogenic Factors ◽  
Internet Resource

The state of plant communities in areas located in the Tersko-Sulak lowland was studied by assessing phytocenotic indicators: the structure of vegetation cover, projective cover, species diversity, species abundance and elevated production, as well as automated decoding methods. There are almost no virgin soils and natural phytocenoses here; all of them have been transformed into agrocenoses (irrigated arable lands and hayfields, rice-trees and pastures). The long-term impact on pasture ecosystems of natural and anthropogenic factors leads to significant changes in the indigenous communities of this region. Phytocenoses are formed mainly by dry-steppe types of cereals with the participation of feather grass, forbs and ephemera, a semi-desert haloxerophytic shrub - Taurida wormwood. At the base of the grass stand is common coastal wormwood and Taurida wormwood - species resistant to anthropogenic influences. Anthropogenic impacts have led to a decrease in the number of species of feed-rich grain crops and a decrease in the overall productivity of pastures. Plant communities in all areas are littered with ruderal species. The seasonal dynamics of the land cover of the sites was estimated by the methods of automatic decoding of satellite images of the Landsat8 OLI series satellite for 2015, dated by the periods: spring - May 20, summer - July 23, autumn - October 20. Satellite imagery data obtained by Landsat satellite with a resolution in the multispectral image of 30 m per pixel, and in the panchromatic image - 10 m per pixel, which correspond to the requirements for satellite imagery to assess the dynamics of soil and vegetation cover. Lower resolution data, for example, NDVI MODIS, does not provide a reliable reflection of the state of soil and vegetation cover under arid conditions. In this regard, remote sensing data obtained from the Internet resource https://earthexplorer.usgs.gov/ was used.

MOSAICITY OF THE VEGETATION COVER OF THE KOCHUBEY BIOSPHERE STATION PASTURES

1970 ◽  
pp. 40-42
Author(s):  
М. А. Babaeva ◽  
S. V. Osipova
Keyword(s):  
Plant Species ◽  
Vegetation Cover ◽  
Cynodon Dactylon ◽  
Plant Cover ◽  
Avena Fatua ◽  
Living Environment ◽  
Anthropogenic Factors ◽  
Indigenous Species ◽  
Fodder Plants ◽  
Falcaria Vulgaris

The regularities of changes in the resistance of different groups of fodder plants to adverse conditions were studied. This is due to the physiological properties that allow them to overcome the harmful effects of the environment. As a result of research species - plant groups with great adaptive potential to the harsh continental semi-desert conditions were identified. Monitoring observation and experimental studies showed too thin vegetation cover as a mosaic, consisting of perennial xerophytic herbs and semishrubs, sod grasses, saltwort and wormwood, as well as ephemera and ephemeroids under the same environmental conditions, depending on various climatic and anthropogenic factors. This is due to the inability or instability of plant species to aggressive living environment. It results in horizontal heterogeneity of the grass stand, division into smaller structures, and mosaic in the vegetation cover of the Kochubey biosphere station. The relative resistance to moderate stress was identified in the following species from fodder plants Agropyron cristatum, A. desertorum, Festuca valesiaca, Cynodon dactylon, Avena fatua; as for strong increasing their abundance these are poorly eaten plant species Artemisia taurica, Atriplex tatarica, Falcaria vulgaris, Veronica arvensis, Arabidopsis thaliana and other. On the site with an increasing pressure in the herbage of phytocenoses the number of xerophytes of ruderal species increases and the spatial structure of the vegetation cover is simplified. In plant communities indigenous species are replaced by adventive plant species. The mosaic of the plant cover of phytocenoses arises due to the uneven distribution in the space of environmental formation, i.e. an edificatory: Salsola orientalis, S. dendroides, Avena fatua, Cynodon dactylon, Artemisia taurica, A. lercheanum, Xanthium spinosum, Carex pachystyli, under which the remaining components of the community adapt. Based on the phytocenotic indicators of pasture phytocenoses it can be concluded that the vegetation cover is in the stage of ecological stress and a decrease in the share of fodder crops and an increase in the number of herbs indicates this fact.

Modeling Dynamic Shock Loads for High-Pressure/Deep-Water Tubing-Conveyed Perforating Operations in the Gulf of Mexico

2012 ◽  
Author(s):  
Rick L. Giunta ◽  
Cam Van Le ◽  
Martin F. Schoener-Scott ◽  
Ryan Neal Anderson ◽  
Joshua Monroe Glass
Keyword(s):  
High Pressure ◽  
Gulf Of Mexico ◽  
Deep Water ◽  
Shock Loads

scholarly journals Experimental study of growth kinetics of CO2 hydrates and multiphase flow properties of slurries in high pressure flow systems

RSC Advances ◽  
2019 ◽  
Vol 9 (56) ◽  
pp. 32873-32888 ◽  
Author(s):  
Xiao-fang Lv ◽  
Jiang-wei Zuo ◽  
Yang Liu ◽  
Shi-Dong Zhou ◽  
Da-yong Lu ◽  
...  
Keyword(s):  
Experimental Study ◽  
High Pressure ◽  
Growth Kinetics ◽  
Deep Water ◽  
Oil And Gas ◽  
Flow Properties ◽  
Field Development ◽  
Water Transportation ◽  
Oil And Gas Pipelines ◽  
Kinetics Of

The formation and accumulation of hydrates in high pressure oil and gas pipelines bring great risks to field development and deep-water transportation.

scholarly journals Rheology of THF hydrate slurries at high pressure

2020 ◽  
Vol 75 ◽  
pp. 16
Author(s):  
Paulo H. de Lima Silva ◽  
Mônica F. Naccache ◽  
Paulo R. de Souza Mendes ◽  
Adriana Teixeira ◽  
Leandro S. Valim
Keyword(s):  
High Pressure ◽  
Low Temperature ◽  
Natural Gas ◽  
Deep Water ◽  
Flow Behavior ◽  
Oil Industry ◽  
Production Lines ◽  
Oil Emulsions ◽  
Slurry Viscosity ◽  
Financial Losses

One of the main issues in the area of drilling and production in deep and ultra-deep water in the oil industry is the formation of natural gas hydrates. Hydrates are crystalline structures resembling ice, which are usually formed in conditions of high pressure and low temperature. Once these structures are formed, they can grow and agglomerate, forming plugs that can eventually completely or partially block the production lines, causing huge financial losses. To predict flow behavior of these fluids inside the production lines, it is necessary to understand their mechanical behavior. This work analyzes the rheological behavior of hydrates slurries formed by a mixture of water and Tetrahydrofuran (THF) under high pressure and low temperature conditions, close to the ones found in deep water oil exploration. The THF hydrates form similar structures as the hydrates originally formed in the water-in-oil emulsions in the presence of natural gas, at extreme conditions of high pressure and low temperature. The experiments revealed some important issues that need to be taken into account in the rheological measurements. The results obtained show that the hydrate slurry viscosity increases with pressure. Oscillatory tests showed that elasticity and yield stress also increase with pressure.

Application of High Pressure Jet Grouting Technology in the Seepage Control of Earth Dam Reinforcement

2011 ◽  
Vol 291-294 ◽  
pp. 3259-3263
Author(s):  
Cong Jiao Zhang ◽  
Shi Bao Zhang ◽  
Feng Shan Fan
Keyword(s):  
High Pressure ◽  
Technological Process ◽  
Earth Dam ◽  
Construction Equipment ◽  
Dam Foundation ◽  
Jet Grouting ◽  
Design Requirements ◽  
Wall Construction ◽  
Construction Practice

Based on the construction practice of strengthening dam foundation and cross-strait dam end (0+149～0+330) high pressure jet grouting impervious wall of an earth dam, this paper expounds the construction equipment, technological process, construction parameters and construction method of high pressure jet grouting impervious wall construction. By analyzing the impervious wall’s depth, continuity, strength, permeable rate, the quality of the wall is eligible, and its indexes comfort the design requirements. The experiences are useful in similar earth dam reinforcement construction.

Reliability Based Deep Water Spool Piece Design

2013 ◽  
Author(s):  
Naresh Juluri ◽  
Elie Dib ◽  
Sherif el-Gebaly ◽  
Philip Cooper
Keyword(s):  
Monte Carlo Simulation ◽  
High Pressure ◽  
Monte Carlo ◽  
Deep Water ◽  
Square Root ◽  
Bending Moments ◽  
Industry Practice ◽  
Fabrication Tolerances ◽  
Outside Diameter ◽  
A Current

Long spools are often required to absorb the end expansion of deep water high pressure and high temperature flowlines. These spools typically have significant metrology and fabrication tolerances. Metrology and spool fabrication tolerances lead to misalignments at the connector hub face. Residual loads then arise from spool deformation due to the installation forces that are required to match-up the connector faces. It is a current industry practice to design the spools for multiple independent tolerances at extreme limits in all directions. Previous project experience shows that the Algebraic Sum (AS) combination of multiple independent tolerances at extreme limits may result in large spools where the probability of occurrence of these tolerances at extreme limits is quite low. The use of less conservative SRSS (square root of sum of squares) combination has been suggested in this paper as an alternative to the Algebraic Sum combination. Due to the large number of misalignment components, the probability of exceeding the loads in the spool and at the connector obtained by the SRSS method is small and is within the applicable failure probabilities defined in DNV-OS-F101. The SRSS method is demonstrated in this paper by using a Monte Carlo simulation. Five different spools have been analysed to demonstrate the suitability of using SRSS misalignments when the spools are designed to DNV-OS-F101. The spools considered include 10″, 16″ and 20″ outside diameter spools to represent different sizes at different loading combinations. Maximum bending moments in the spool and maximum moments at the connector have been considered to check the SRSS feasibility. The results indicate that it is acceptable to use SRSS misalignments as an alternative to AS misalignments. Considering SRSS misalignments in preference to AS leads to reduced spool size and reduced loadings on connectors.

Benefits and Deep Water Install Ability Challenges of Residual Curvature Method for Lateral Buckling Mitigation

2017 ◽  
Author(s):  
Erwan Karjadi ◽  
Phil Cooper ◽  
Henk Smienk ◽  
Ferry Kortekaas
Keyword(s):  
High Pressure ◽  
Deep Water ◽  
Local Buckling ◽  
Bending Moment ◽  
Lateral Buckling ◽  
Curved Pipe ◽  
Fea Model ◽  
Water Pipelines ◽  
Residual Curvature ◽  
Curved Section

One way to control lateral buckling in the operation phase for High Pressure High Temperature (HPHT) pipelines is by deliberately introducing residual curvature sections at intervals along the pipeline by adjusting the straightener settings of the pipelay tower, as described in a patent held by Statoil [1]. This method has been applied with reel-lay installation for a number of shallow water pipelines in Europe (Statoil’s Skuld project and Total’s Edradour project). The paper presents the benefits as well as the feasibility of the use of Residual Curvature Method (RCM) to control lateral buckling for deep water applications which involves high top tension in the overbend and high pressure and twist of the RC section in the sagbend. The study cases consider the application of the method for pipelines in 1850m water depth which are pushing the pipe top tension close to the limit of the capacity of the tensioners of Heerema Marine Contractor’s (HMC) Reel-lay vessel the Aegir. There are some challenges of the application of the residual curve method for deep water pipelines. Due to high top tension, some potential issues are investigated during lowering of the curved section from the straightener, passing the tensioners and through the J-lay tower into the water to the seabed. Detailed analyses have been performed to check the interaction of the residual curved pipe section against the tensioners (the effect of the squeeze load on the RC section) and to assess the maximum bending moment generated when the residual curved section is under high top tension below the tensioners against the Load Controlled Condition (LCC) for local buckling bending moment limit. Another consideration is the increase of hydrostatic pressure in deep water which could limit the allowable bending moment in the sagbend when lowering the curved sections to the seabed. Discussions are presented to the feasibility of the concept including the proposed ways of mitigation for the aforementioned potential issues. The paper will also show an improved prediction of pipe twist/roll by comparing a published analytical 2D plane solution against the 3D FEA model prediction. The improved prediction, which considers the out of plane bending component of the pipe catenary, results in an increase of pipe twist in the sagbend section. This reduces the bending moment in the residual curved section when entering the sagbend and increases the probability to roll the curved section over to the horizontal plane on the seabed.

Sign in / Sign up

Export Citation Format

Share Document