scholarly journals EVALUATION OF POSSIBLE CHANGES IN THE RIVER LINE OF THE OKA BASIN FOR THE COMING PERIOD OF THE FIRST HALF OF THE XXI CENTURY

Author(s):  
G. Kh. Ismaiylov ◽  
◽  
N.V. Muraschenkova ◽  

A retrospective analysis and assessment of long-term changes in the annual and seasonal runoff of the Oka River basin over a long 131-year observation period (1881 / 1882–2011/2012) was performed. The changes in the annual distribution of the Oka river runoff over the seasons of the year (spring flood, summer-autumn and winter low water) from its annual value for the selected time periods (before and after 1976/1977) are considered. It has been noted that over the past decades, river runoff has been formed in new climatic conditions associated with global changes and, as a result, regional climate. The assessment of possible changes in the annual and seasonal runoff of the Oka River basin (to the final alignment – the city of Kaluga, with a basin area of 54,900 km2 ) in the first half of the 21st century is carried out. In assessing changes in the river flow of the Oka basin for the future period, the method of trends (trends) is used, based on the identification of cycles in fluctuations in hydrological characteristics and unidirectional trends (trends) inherent in individual phases (ups and downs) of these cycles, as well as to the establishment of functional (correlation) relationships between environmental factors (climatic, anthropogenic) and the nature of the response (river flow). In this case, the trend model serves as an alternative to the homogeneity hypothesis of long-term fluctuations in river flow. The change in the future values of the river flow of the Oka basin was estimated using averaged data of 30-year periods of time characterized by relative stationarity of climatic and hydrological conditions. The dynamics of the average 30-year values of the annual runoff in the upper reaches of the Oka River (the closure target is the city of Kaluga for the period 1881/1882–2011/2012) is considered. Possible forecasted mean annual values of the annual flow of the Oka River for the first half of the 21st century are obtained

Author(s):  
Tetiana Bauzha ◽  
Liudmyla Gorbachova

Abstract In the last decades, according to researches of scientists of the world becomes more evident that the global and regional climate changes impact on the water regime of rivers and leads to break of the stationarity of observations series. In this study we analysed the long-term (since the beginning of the observations to 2012) average annual flow of the Southern Buh River Basin (37 gauging stations) and its cyclical fluctuations during a long period of time. The methodological approaches based on the using of hydro-genetic methods for estimation the homogeneity and stationarity of hydrological series were used. We researched that series of observations are homogeneous and stationary. However, not all series of observations were representative for determination of the stable average value. The presented results illustrate that the long-term fluctuations of the average annual flow at all gauging stations is synchronous. Therefore, the climatic conditions of the flow formation are homogeneous. However, these fluctuations are not always synchronous phase. We found out that the average annual flow in this basin fluctuates and has decreasing trend in the last decade. It is due to cyclical fluctuations of the river flow. We calculated the statistical parameters for all gauging stations.


2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Raka Maulana ◽  
Yulianti Pratama ◽  
Lina Apriyanti

<p>Some areas in the city of Bandung is an area that dilitasi by the flow of the river, to prevent the introduction of garbage into the river basin is necessary to note the waste management systems in residential areas along the river. Cidurian river has a length of 24.86 Km along the river flow. Consists of the city of Bandung and Bandung regency. Administrative regions Cidurian River past eight (8) districts, from the region in the District Kiaracondong precisely Village Babakan Babakan Sari and Surabaya populous and the most densely populated. Thus, there should be community-based waste management in the form of a reduction in resources to prevent potential entry of waste into the river basin. Planning waste reduction will be divided into two, namely the reduction of inorganic waste with waste bank then the reduction of organic waste with absorption holes biopori, and bio reactor mini determination of the reduction is determined by the results of the analysis of the sampling covers the composition and garbage, then the result of the measurement characteristics test and analysis results questionnaire.</p>


2021 ◽  
Vol 21 ◽  
pp. 100206
Author(s):  
Connie A. Woodhouse ◽  
Rebecca M. Smith ◽  
Stephanie A. McAfee ◽  
Gregory T. Pederson ◽  
Gregory J. McCabe ◽  
...  

2021 ◽  
pp. 98-104
Author(s):  
G. KH. ISMAIYLOV ◽  
◽  
N. V. MURASCHENKOVA ◽  
I. G. ISMAIYLOVA

The results of the analysis and assessment of long-term changes in the qualitative characteristics of the Oka River runoff are presented. To analyze the temporal dynamics of the variability of the average annual and maximum concentrations of pollutants in the runoff of the Oka River, we used long-term observational data on typical pollutants for the period 1984-2019. The assessment of the state of the quality of surface waters of the Oka River was carried out according to the values of the concentrations of pollutants in the upper, middle and lower reaches of the river. The dynamics of the main pollutants of the following indicators is considered: ammonium nitrogen, oil products, copper and zinc compounds and easily oxidized organic substances. It was found that in the upper reaches of the river (according to observations of the Oka – Orel city) the main pollutants are ammonium nitrogen and copper compounds, the average annual concentrations of which respectively increased to 9 values. A similar situation was observed downstream of the river (the Oka River – Kaluga city). As a result of the analysis, it was revealed that more noticeable changes in the concentration of pollutants are observed in the section of the river from the city of Murom to the city of Dzerzhinsk. Near the city of Murom, the content of oil products in the water sharply increases. From the beginning of the study period (1984) and until 1995, the average annual concentration varied from 5 to 30 values, and the maximum concentration in the year in creased to 87 values. After 2000, the content of oil products in water dropped sharply and the average annual value did not exceed 3 values, and the maximum concentration was 4-6 values. The paper analyzes the frequency of cases of exceeding the maximum permissible concentrations of pollutants in the Oka River in the mouth of the river. There was a high repeatability of the content of copper compounds in water, which varied from 70 to 88%. The frequency of cases of excess of easily oxidized organic matter in the mouth of the Oka River varied from 64 to 74%. Relatively low, although stable, the repeatability of the content of oil products in water remained, which ranged from 23 to 42%.


2021 ◽  
Author(s):  
Hanna Bolbot ◽  
Vasyl Grebin

&lt;p&gt;The current patterns estimation of the water regime under climate change is one of the most urgent tasks in Ukraine and the world. Such changes are determined by fluctuations in the main climatic characteristics - precipitation and air temperature, which are defined the value of evaporation. These parameters influence on the annual runoff distribution and long-term runoff fluctuations. In particular, the annual precipitation redistribution is reflected in the corresponding changes in the river runoff.&lt;br&gt;The assessment of the current state and nature of changes in precipitation and river runoff of the Siverskyi Donets River Basin was made by comparing the current period (1991-2018) with the period of the climatological normal (1961-1990).&lt;br&gt;In general, for this area, it was defined the close relationship between the amount of precipitation and the annual runoff. Against the background of insignificant (about 1%) increase of annual precipitation in recent decades, it was revealed their redistribution by seasons and separate months. There is a decrease in precipitation in the cold period (November-February). This causes (along with other factors) a decrease in the amount of snow and, accordingly, the spring flood runoff. There are frequent cases of unexpressed spring floods of the Siverskyi Donets River Basin. The runoff during March-April (the period of spring flood within the Ukrainian part of the basin) decreased by almost a third.&lt;br&gt;The increase of precipitation during May-June causes a corresponding (insignificant) increase in runoff in these months. The shift of the maximum monthly amount of precipitation from May (for the period 1961-1990) to June (in the current period) is observed.&lt;br&gt;There is a certain threat to water supply in the region due to the shift in the minimum monthly amount of precipitation in the warm period from October to August. Compared with October, there is a higher air temperature and, accordingly, higher evaporation in August, which reduces the runoff. Such a situation is solved by rational water resources management of the basin. The possibility of replenishing water resources in the basin through the transfer runoff from the Dnieper (Dnieper-Siverskyi Donets channel) and the annual runoff redistribution in the reservoir system causes some increase in the river runoff of summer months in recent decades. This is also contributed by the activities of the river basin management structures, which control the maintenance water users' of minimum ecological flow downstream the water intakes and hydraulic structures in the rivers of the basin.&lt;br&gt;Therefore, in the period of current climate change, the annual runoff distribution of the Siverskyi Donets River Basin has undergone significant changes, which is related to the annual precipitation redistribution and anthropogenic load on the basin.&lt;/p&gt;


2012 ◽  
Vol 43 (1-2) ◽  
pp. 73-90 ◽  
Author(s):  
Fei Yuan ◽  
Liliang Ren ◽  
Zhongbo Yu ◽  
Yonghua Zhu ◽  
Jing Xu ◽  
...  

Vegetation and land-surface hydrology are intrinsically linked under long-term climate change. This paper aims to evaluate the dynamics of potential natural vegetation arising from 21st century climate change and its possible impact on the water budget of the Hanjiang River basin in China. Based on predictions of the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC-SRES) A1 scenario from the PRECIS (Providing Regional Climates for Impact Studies) regional climate model, changes in plant functional types (PFTs) and leaf area index (LAI) were simulated via the Lund-Potsdam-Jena dynamic global vegetation model. Subsequently, predicted PFTs and LAIs were employed in the Xinanjiang vegetation-hydrology model for rainfall–runoff simulations. Results reveal that future long-term changes in precipitation, air temperature and atmospheric CO2 concentration would remarkably affect the spatiotemporal distribution of PFTs and LAIs. These climate-driven vegetation changes would further influence regional water balance. With the decrease in forest cover in the 21st century, plant transpiration and evaporative loss of intercepted canopy water will tend to fall while soil evaporation may rise considerably. As a result, total evapotranspiration may increase moderately with a slight increase in annual runoff depth. This indicates that, for long-term hydrological prediction, climate-induced changes in terrestrial vegetation cannot be neglected as the terrestrial biosphere plays an important role in land-surface hydrological responses.


Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 167 ◽  
Author(s):  
Ashley Fisher ◽  
Kiana Saniee ◽  
Charis van der Heide ◽  
Jessica Griffiths ◽  
Daniel Meade ◽  
...  

We use climatic conditions that are associated with known monarch butterfly overwintering groves in California to build a Maxent model, and focus on the fine scale probability of overwintering grove occurrence in a topographically complex region of the state (Santa Barbara County). Grove locations are known from recent and historical surveys and a long-term citizen science database. The climatic niche model performs well, predicting that overwintering habitat is most likely to occur along the coast and at low elevations, as shown by empirical data. We then use climatic variables in conjunction with climate change scenarios to model the future location of overwintering habitat, and find a substantial shift in the predicted distribution. Under a plausible scenario, the probability of occurrence of overwintering habitat directly reflects elevation, with coastal regions having a reduced probability relative to today, and higher elevation sites increasing in probability. Under a more extreme scenario, high probability sites are only located along ridgelines and in mountaintop regions of the county. This predicted shift in distribution is likely to have management implications, as sites that currently lack monarchs may become critical to conservation in the future. Our results suggest that estimating the size of the western overwintering population in the future will be problematic, unless annual counts compensate for a shift in the distribution and a potential change in the number and location of occupied sites.


2019 ◽  
Author(s):  
Katixa Lajaunie-Salla ◽  
Aldo Sottolichio ◽  
Sabine Schmidt ◽  
Xavier Litrico ◽  
Guillaume Binet ◽  
...  

Abstract. In view of future coastal hypoxia widespreading, it is essential to define management solutions to preserve a good quality of coastal ecosystems. The lower Tidal Garonne River (TGR, SW France), characterized by the seasonal presence of a turbidity maximum zone and urban water discharges, is subject to episodic hypoxia events during summer low river flow periods. The future climatic conditions (higher temperature; summer droughts) but also an increasing urbanization could enhance hypoxia risks near the city of Bordeaux in the next decades. A 3D model of dissolved oxygen (DO), which couples hydrodynamics, sediment transport and biogeochemical processes, is used to assess the efficiency of different management solutions on TGR oxygenation during summer low-discharge periods. We have runned different scenarios of reduction of urban sewage overflows, displacement of urban discharges downstream from Bordeaux, and/or temporary river flow support during summer period. The model shows that each option limits hypoxia, but with variable efficiency over time and space. Sewage overflow reduction improves DO levels only locally near the city of Bordeaux. Downstream relocation of wastewater discharges allows to reach better oxygenation level in the lower TGR. The support of low river flow limits the upstream TMZ propagation and dilutes TGR waters with well-oxygenated river waters. Scenarios combining wastewater network management and low water replenishment indicate an improvement in water quality over the entire TGR. These modelling outcomes constitute important tools for local water authorities to develop the most appropriate strategies to limit hypoxia in TGR.


2007 ◽  
Vol 34 (10) ◽  
pp. 1276-1288 ◽  
Author(s):  
Daryl MacLeod ◽  
Susanna Ho ◽  
Ryan Wirth ◽  
Ludo Zanzotto

Waste tire crumb rubber materials (CRM) were used to modify paving asphalts. The mixing time, hot-storage stability, Superpave grades, pumping and handling properties, phase separation tests, and repeated creep properties of the modified asphalts were studied using base asphalts of different hardness. Applying the Long-Term Pavement Performance (LTPP) program and the Transportation Association of Canada (TAC) model, optimal levels of CRM and suitable base asphalts were selected for the climatic conditions of Lethbridge, Alberta, Canada. High-temperature grade bumping protocol, regarding traffic volume and speed, was also considered. With joint efforts from the Tire Recycling Management Association of Alberta (TRMA), Husky Energy, and the City of Lethbridge, three test sections in different Lethbridge locations with various traffic volumes were paved from the years 2003 to 2005. So far, the City of Lethbridge is pleased with the initial performance of the test sections.Key words: waste tire, crumb rubber materials (CRM), paving asphalt, recycled, modification, Superpave, repeated creep, field test.


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