scholarly journals Factors of lowering the Lake Syne levels and measures to improve its ecological state

2020 ◽  
pp. 101-111
Author(s):  
O. M. Kozytskyi ◽  
S. A. Shevchuk ◽  
I. A. Shevchenko ◽  
N. V. Logunova
Keyword(s):  
Water Content ◽  
Air Temperature ◽  
Catchment Area ◽  
Negative Impact ◽  
Ecological Condition ◽  
Water Levels ◽  
Annual Rainfall ◽  
Anthropogenic Pressure ◽  
Ecological State ◽  
Positive Balance

Relevance of research. The consequences of the intensive rise in air temperature can be clearly seen in the example of shallowing natural reservoirs in which, unlike ponds and reservoirs, there it is impossible to regulate runoff. This, in particular, applies to Syne Lake, located on the northwestern outskirts of Kyiv. Since the middle of the last century, the lake and the area around it have undergone significant anthropogenic pressure, which has had a negative impact on its ecological condition. The development of a comprehensive system of measures to improve the ecology of the lake requires a thorough study of the main factors in the formation of the hydrological regime of the reservoir and their discrete assessment. Objective of research is to identify natural and man-made factors that have led to a significant decrease in the Syne Lake levels in recent years and to develop of measures to improve its ecological state. Research results. The increase in evaporation from the water surface, the decrease in precipitation and inflow from the catchment caused a significant decrease in water levels in the lake and its morphological parameters. Since 2001, the area of ​​the water mirror has decreased from 3.4 ha to 2.6 ha, the water level has decreased by more than 1 m, and the shore horizon has shifted to the middle by more than 10 m. The decrease in the water content of the lake was due to changes in the components of its water balance, which was directly affected by factors, both natural and man-made.  As a result of road construction and intensive development of the area around the lake, the catchment area decreased from 758 ha to 21 ha, which caused a sharp decrease in surface runoff to the lake. A modern network of drainage and stormwater systems within the natural catchment area of ​​the lake provides drainage into the Dnieper River. The lake overgrowing and siltation by 1-1.5 m led to clogging of underground springs and, accordingly, to a decrease in pressure underground supply. Other reasons for the lake shallowing are a decrease in precipitation and an increase in air temperature. Having a climatic standard 649 mm in Kyiv in 2019, only 521 mm fell, and in general for the last 5 years the annual rainfall has decreased by an average of 87 mm per year. The average air temperature compared to the climatic standard over the past 10 years has increased by 1.9 °C, and in the hot 2019 - by 2.9 °C, which led to a significant increase in evaporation. Compared to the climatic standard, evaporation from the surface of Kyiv reservoirs has increased over the last 10 years by 127 mm, and in 2019 it reached a record rate of 911 mm. Only due to the increased evaporation from the surface of the lake and reduced rainfall, the lake level in 2019 decreased by 30.4 cm. The results of the performed research show that for the last 5 years the positive balance of moisture in the catchment is maintained. The total amount of precipitation is 161 mm higher than the evaporation for the same period, but it is 2.4 times less than the climatic standard. In low water years as it was 2015 and 2019, the difference between precipitation and evaporation from the catchment area was only 13 and 20 mm, while in the period of 1961-1990 it was 69 mm. This led to a decrease in groundwater levels and, consequently, a decrease in their inflow to the lake. Conclusion. Intensive reduction of the water content of Syne Lake is due to a complex of natural and man-made factors, including the redistribution of runoff outside the catchment as a result of building in the area, siltation of underground feeding sources, reducing rainfall and increasing evaporation due to rising air temperatures. Reducing the intensity of lake shallowing is possible by increasing the inflow of water, by redirecting to the lake surface (after treatment) and drainage runoff from the natural catchment area of ​​the lake and beyond. Clearing and dredging the lake will increase its depth and improve groundwater inflow.

scholarly journals Ecological condition of the small rivers Ik and Syun in the Sharansky District of the Republic of Bashkortostan

2017 ◽  
Vol 6 (4) ◽  
pp. 57-61
Author(s):  
Elvina Rishatovna Nafikova ◽  
Aysylu Airatowna Islamova
Keyword(s):  
Negative Impact ◽  
Hydrological Regime ◽  
Final Analysis ◽  
Ecological Condition ◽  
Water Bodies ◽  
Nature Management ◽  
Small Rivers ◽  
Ecological State ◽  
Republic Of Bashkortostan ◽  
The Republic

Currently the negative impact of man on aquatic ecosystems is very noticeable. This, in the final analysis, was reflected in the change in the hydrological regime of rivers and lakes. Environmental conditions in many water bodies deteriorated sharply. There are also acute exacerbations of water management situations, deterioration of water use conditions due to the lack of scientifically based principles of nature management in the catchment area, and quantitative and qualitative depletion of water resources due to the combined impact of various sectors of the national economy The ecological state of water bodies largely depends on external influences, the magnitude of which should not exceed the permissible limits. In this case, the ecosystem maintains its stability. The paper deals with the assessment of the ecological state of rivers and their resistance to polluting effects, in particular, an assessment of the quality of the water of the Ik and Syun rivers in the Sharansky District of the Republic of Bashkortostan. Physico-chemical and organoleptic analyses of the rivers have been carried out. The research was conducted in September-May 2016-2017. The analysis of the water was carried out in the analytical laboratories of the Tuimazy inter-district branch of the FBU Center for Hygiene and Epidemiology in the Republic of Bashkortostan. The water quality in the river was estimated using the Mayer index.

Survey of the Ecological State of Eight Man-Made Lakes Within the City Limits of Freiburg, Germany

1992 ◽  
Vol 27 (2) ◽  
pp. 301-310
Author(s):  
Agnes G. Pulvermüller ◽  
Heidulf E. Müller
Keyword(s):  
Escherichia Coli ◽  
Water Quality ◽  
Biochemical Oxygen Demand ◽  
Secchi Depth ◽  
Oxygen Demand ◽  
Ecological Condition ◽  
Ecological State ◽  
Biological Parameters ◽  
The City ◽  
Oxygen Profiles

Abstract The survey of the ecological condition of eight lakes within the city limits of Freiburg included hydrochemical measurements and analyses (oxygen profiles, Secchi depth, pH, biochemical oxygen demand) together with biological parameters (chlorophyll a, phytoplanktonbiomass, Escherichia coli counts), as well as parasitic examinations. Only some of the investigated parameters are presented here. Seven of the eight lakes were found to be eutrophic. The process of eutrophication appears to be still in progress. One lake can be considered to be hypertrophic. Schistosome dermatitis was observed. The water quality in general was considered to be acceptable; suggestions to maintain or improve the water quality are made.

scholarly journals Projection of Hydro-Climatic Extreme Events under Climate Change in Yom and Nan River Basins, Thailand

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 665
Author(s):  
Chanchai Petpongpan ◽  
Chaiwat Ekkawatpanit ◽  
Supattra Visessri ◽  
Duangrudee Kositgittiwong
Keyword(s):  
Climate Change ◽  
Air Temperature ◽  
Extreme Events ◽  
River Basins ◽  
Annual Rainfall ◽  
Extreme Floods ◽  
Extreme Flood ◽  
Rcp 8.5 ◽  
Near Future ◽  
Far Future

Due to a continuous increase in global temperature, the climate has been changing without sign of alleviation. An increase in the air temperature has caused changes in the hydrologic cycle, which have been followed by several emergencies of natural extreme events around the world. Thailand is one of the countries that has incurred a huge loss in assets and lives from the extreme flood and drought events, especially in the northern part. Therefore, the purpose of this study was to assess the hydrological regime in the Yom and Nan River basins, affected by climate change as well as the possibility of extreme floods and droughts. The hydrological processes of the study areas were generated via the physically-based hydrological model, namely the Soil and Water Assessment Tool (SWAT) model. The projected climate conditions were dependent on the outputs of the Global Climate Models (GCMs) as the Representative Concentration Pathways (RCPs) 2.6 and 8.5 between 2021 and 2095. Results show that the average air temperature, annual rainfall, and annual runoff will be significantly increased in the intermediate future (2046–2070) onwards, especially under RCP 8.5. According to the Flow Duration Curve and return period of peak discharge, there are fluctuating trends in the occurrence of extreme floods and drought events under RCP 2.6 from the future (2021–2045) to the far future (2071–2095). However, under RCP 8.5, the extreme flood and drought events seem to be more severe. The probability of extreme flood remains constant from the reference period to the near future, then rises dramatically in the intermediate and the far future. The intensity of extreme droughts will be increased in the near future and decreased in the intermediate future due to high annual rainfall, then tending to have an upward trend in the far future.

scholarly journals Testing Evapotranspiration Estimates Based on MODIS Satellite Data in the Assessment of the Groundwater Recharge of Karst Aquifers in Southern Italy

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 118
Author(s):  
Giovanni Ruggieri ◽  
Vincenzo Allocca ◽  
Flavio Borfecchia ◽  
Delia Cusano ◽  
Palmira Marsiglia ◽  
...  
Keyword(s):  
Groundwater Recharge ◽  
Air Temperature ◽  
Southern Italy ◽  
Remotely Sensed ◽  
Actual Evapotranspiration ◽  
Annual Rainfall ◽  
Karst Aquifers ◽  
Southern Apennines ◽  
Remotely Sensed Data ◽  
Empirical Formulas

In many Italian regions, and particularly in southern Italy, karst aquifers are the main sources of drinking water and play a crucial role in the socio-economic development of the territory. Hence, estimating the groundwater recharge of these aquifers is a fundamental task for the proper management of water resources, while also considering the impacts of climate changes. In the southern Apennines, the assessment of hydrological parameters that is needed for the estimation of groundwater recharge is a challenging issue, especially for the spatial and temporal inhomogeneity of networks of rain and air temperature stations, as well as the variable geomorphological features and land use across mountainous karst areas. In such a framework, the integration of terrestrial and remotely sensed data is a promising approach to limit these uncertainties. In this research, estimations of actual evapotranspiration and groundwater recharge using remotely sensed data gathered by the Moderate Resolution Imaging Spectrometer (MODIS) satellite in the period 2000–2014 are shown for karst aquifers of the southern Apennines. To assess the uncertainties affecting conventional methods based on empirical formulas, the values estimated by the MODIS dataset were compared with those calculated by Coutagne, Turc, and Thornthwaite classical empirical formulas, which were based on the recordings of meteorological stations. The annual rainfall time series of 266 rain gauges and 150 air temperature stations, recorded using meteorological networks managed by public agencies in the period 2000–2014, were considered for reconstructing the regional distributed models of actual evapotranspiration (AET) and groundwater recharge. Considering the MODIS AET, the mean annual groundwater recharge for karst aquifers was estimated to be about 448 mm·year−1. In contrast, using the Turc, Coutagne, and Thornthwaite methods, it was estimated as being 494, 533, and 437 mm·year−1, respectively. The obtained results open a new methodological perspective for the assessment of the groundwater recharge of karst aquifers at the regional and mean annual scales, allowing for limiting uncertainties and taking into account a spatial resolution greater than that of the existing meteorological networks. Among the most relevant results obtained via the comparison of classical approaches used for estimating evapotranspiration is the good matching of the actual evapotranspiration estimated using MODIS data with the potential evapotranspiration estimated using the Thornthwaite formula. This result was considered linked to the availability of soil moisture for the evapotranspiration demand due to the relevant precipitation in the area, the general occurrence of soils covering karst aquifers, and the dense vegetation.

Comparison of Water Thickness Profiles of Compressed PEMFC GDLs

2011 ◽  
Author(s):  
Pradyumna Challa ◽  
James Hinebaugh ◽  
A. Bazylak
Keyword(s):  
Water Content ◽  
Liquid Water ◽  
Water Distribution ◽  
Polymer Electrolyte Membrane ◽  
Water Injection ◽  
Liquid Water Content ◽  
Gas Diffusion ◽  
Injection Rate ◽  
Water Levels ◽  
Ex Situ

In this paper, through-plane liquid water distribution is analyzed for two polymer electrolyte membrane fuel cell (PEMFC) gas diffusion layers (GDLs). The experiments were conducted in an ex situ flow field apparatus with 1 mm square channels at two distinct flow rates to mimic water production rates of 0.2 and 1.5 A/cm2 in a PEMFC. Synchrotron radiography, which involves high intensity monochromatic X-ray beams, was used to obtain images with a spatial and temporal resolution of 20–25 μm and 0.9 s, respectively. Freudenberg H2315 I6 exhibited significantly higher amounts of water than Toray TGP-H-090 at the instance of breakthrough, where breakthrough describes the event in which liquid water reaches the flow fields. While Freudenberg H2315 I6 exhibited a significant overall decrease in liquid water content throughout the GDL shortly after breakthrough, Toray TGP-H-090 appeared to retain breakthrough water-levels post-breakthrough. It was also observed that the amount of liquid water content in Toray TGP-H-090 (10%.wt PTFE) decreased significantly when the liquid water injection rate increased from 1 μL/min to 8 μL/min.

Modelling pavement temperature for winter maintenance operations

2004 ◽  
Vol 31 (2) ◽  
pp. 369-378 ◽  
Author(s):  
Aly Sherif ◽  
Yasser Hassan
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Negative Impact ◽  
Weather Conditions ◽  
Statistical Modelling ◽  
Dew Point ◽  
Road Maintenance ◽  
Winter Maintenance ◽  
Pavement Surface ◽  
Pavement Temperature

Road and highway maintenance is vital for the safety of citizens and for enabling emergency and security services to perform their essential functions. Accumulation of snow and (or) ice on the pavement surface during the wintertime substantially increases the risk of road crashes and can have negative impact on the economy of the region. Recently, road maintenance engineers have used pavement surface temperature as a guide to the application of deicers. Stations for road weather information systems (RWIS) have been installed across Europe and North America to collect data that can be used to predict weather conditions such as air temperature. Modelling pavement surface temperature as a function of such weather conditions (air temperature, dew point, relative humidity, and wind speed) can provide an additional component that is essential for winter maintenance operations. This paper uses data collected by RWIS stations at the City of Ottawa to device a procedure that maximizes the use of a data batch containing complete, partially complete, and unusable data and to study the relationship between the pavement surface temperature and weather variables. Statistical models were developed, where stepwise regression was first applied to eliminate those variables whose estimated coefficients are not statistically significant. The remaining variables were further examined according to their contribution to the criterion of best fit and their physical relationships to each other to eliminate multicollinearities. The models were further corrected for the autocorrelation in their error structures. The final version of the developed models may then be used as a part of the decision-making process for winter maintenance operations.Key words: winter maintenance, pavement temperature, statistical modelling, RWIS.

scholarly journals Simulation and Assessment of Groundwater for Domestic and Irrigation Uses

2019 ◽  
Vol 5 (9) ◽  
pp. 1877-1892 ◽  
Author(s):  
Majed Rodhan Hussain ◽  
Basim Sh. Abed
Keyword(s):  
Cross Sections ◽  
Three Dimensional ◽  
Water Quality Assessment ◽  
Alluvial Fan ◽  
Water Levels ◽  
Specific Yield ◽  
Annual Rainfall ◽  
Steady State Condition ◽  
Groundwater Samples ◽  
One Year

The alluvial fan of Mandali located between latitude 30˚45’00” N longitude 45˚30’00” E in east of Diyala Governorate, Iraq. Thirty-five wells were identified in the study area with average depth of 84 m and estimated area of 21550 ha. A three-dimensional conceptual model was prepared by using GMS program. From wells cross sections, four geological layers have been identified. The hydraulic conductivity of these layers was calculated for steady state condition, where the water levels for nine wells distributed over the study area were observed at same time. Afterward, PEST facility in the GMS was used to estimate the aquifer hydraulic characteristics. Other characteristics such as storage coefficient and specific yield have been determined from one year field observations that were collected by General Authority of Groundwater, Diyala Governorate. Also, the observations were used for calibration of unsteady state model. Then wells were hypothetically redistributed and increased to 103 wells, assuming a distance of 1500 m between the wells, a well productivity rate of were 7 l/s, annual rainfall rate was used for recharging. Three different wells operating times were suggested and these 6, 12, and 18 hr/day with total discharge of 150, 300, 450 m3/day and maximum drawdown of 7, 11, and 20 m respectively. For water quality assessment, the collected groundwater samples were analysed at the laboratory.  Results showed that the TDS in all wells was ranged from 1000-3000 mg/l but TDS in well number 18 was exceeded 3000 mg/l which indicate that the groundwater in this well is not recommended to be used for irrigation. According to Iraqi standard for drink (IQS 2009), it can be used for drinking if saline treatment units were provided.

scholarly journals PRODUCTIVITY AND QUALITY OF SUGAR CONTENT, TOTAL ACID, PH, AND GANDARIA FRUIT WATER LEVELS (BOUEA MACROPHYLLA GRIIFF) IN DIFFERENT GEOGRAPHICAL CONDITIONS IN AMBON ISLAND (AN ANALYSIS OF MALUKU ENDEMIC PLANTS)

2020 ◽  
Vol 1 (1) ◽  
pp. 52-62
Author(s):  
Pamella Mercy Papilaya
Keyword(s):  
Water Content ◽  
Sampling Method ◽  
Sugar Content ◽  
Total Sugar ◽  
Water Levels ◽  
Endemic Plants ◽  
Total Acid ◽  
Acid Ph ◽  
Acidity Level

Gandaria plant grows with tree habitus with a height of up to 27 m Spread of gandaria plants in Maluku, generally on Ambon Island and Saparua on Ambon Island, gandaria plants are spread from the coast to the hills. This study aims to determine the quality of sugar content, total acid, pH, water content and production of gandaria fruit (Bouea macrophylla Griff) in different geographical conditions on the island of Ambon using a purposive sampling method and laboratory analysis. The results showed that at an altitude of 0-400 asl with a production of 654 kg, 400-700 asl with a production of 681 kg and an altitude of 700-1100 asl producing 925 kg and the height of the place also affected the quality of gandaria with an average total sugar of 12.69%, content water 80.18%, acidity level 6.81% and pH 3. It was concluded that the higher the altitude of the place will affect the production and quality of gandaria fruit (Bouea macrophylla Griff).

scholarly journals Influence of the quality of drinking water supply sources on the formation of the ecologically-dependent pathology of the population of the Republic of Dagestan

2021 ◽  
Vol 15 (4) ◽  
pp. 168-176
Author(s):  
M. G. Daudova ◽  
R. B. Bagomedova ◽  
K. K. Bekshokov ◽  
M. M. Medzhidova ◽  
S. M. Nakhibashev ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Negative Impact ◽  
Kidney Diseases ◽  
Ecological Condition ◽  
Drinking Water Quality ◽  
Chemical Contamination ◽  
The Republic

Aim. Study of the influence of drinking water quality on the ecologically-dependent morbidity of the population of the Republic of Dagestan.Material and Methods. Methods of current and retrospective analysis of regional health indicators and methods of mathematical-statistical and medical-geographical analysis were used. Statistical processing of the results was carried out using the STATISTICA and Excel software packages. When carrying out laboratory studies on the quality of drinking water, we used a Lumex atomic absorption spectrometer "MGA-915MD".Results. Numerous hygiene studies indicate the direct impact of unsatisfactory drinking water quality on the health of a population. The relationship between sanitary and chemical indicators and the incidence rate for a number of nosological forms has been proven. It is generally accepted that human health is influenced by lifestyle factors (working, living and relaxation conditions), heredity and the ecological condition of the area of residence, including the quality of drinking water. Although it is not possible to differentiate the share of the negative effect caused by the consumption of poor quality drinking water but the incidence of certain nosological forms (cancer of the esophagus, gastrointestinal tract and kidney diseases) in the those regions of the Republic of Dagestan under consideration correlates with the characteristics of drinking water.Conclusion. The problem of pollution of water supply sources for the population in the dynamics of the long-term remains a priority concern. The quality and safety of drinking water are decreasing, which cannot but have a negative impact on public health. Correlation linkages between indicators of drinking water quality and oncological morbidity of the population were also established in indicators below the maximum permissible concentrations, which corresponds to a typical logistic model of causal relationships and serves as evidence of the high dependence of health disorders on chemical contamination of water supply sources. 

scholarly journals Probability Assessment of Slope Instability in Seasonally Cold Regions under Climate Change

2021 ◽  
Author(s):  
Yulong Zhu ◽  
Tatsuya Ishikawa ◽  
Tomohito J. Yamada ◽  
Srikrishnan Siva Subramanian
Keyword(s):  
Climate Change ◽  
Slope Stability ◽  
Water Content ◽  
Air Temperature ◽  
Climate Changes ◽  
Slope Instability ◽  
Climate Factors ◽  
Cold Regions ◽  
The Past ◽  
Assessment Approach

Abstract This paper proposes an effective approach for evaluating the influences of climate change on slope stability in seasonally cold regions. Firstly, to semi-quantitatively assess the effects of climate changes on the uncertainty of climate factors, this study analyzes the trend of the two main climate factors (precipitation and air temperature) by the regression analysis using the meteorological monitoring data of the past 120 years in different scales (e.g., world, country (Japan), and city (Sapporo)), and the meteorological simulation data obtained by downscaling the outputs of three different regional atmospheric models (RAMs) with lateral boundary conditions from three different general circulation models (GCMs). Next, to discuss the effects of different climate factors (air temperature, precipitation, etc.) and to determine the key climate factors on the slope instability, an assessment approach for evaluating the effects of climate changes on slope instability is proposed through the water content simulation and slope stability analysis using a 2-dimensional (2D) finite element method (FEM) homogeneous conceptual slope model with considering freeze-thaw action. Finally, to check the effectiveness of the above assessment approach, assessment of instability of an actual highway embankment slope with the local layer geometry is done by applying the past and predicted future climate data. The results indicate that affected by global warming, the air temperature rise in some cold cities is more serious. The predicted future weather will affect the shape of the normal density curve (NDC) of the distribution of slope failures in one year. The climate changes (especially the increase in precipitation) in the future will increase the infiltration during the Spring season. It will lengthen the time that the highway slope is in an unstable state due to high volumetric water content, thereby enhancing the instability of the slopes and threatening more slopes in the future.

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