scholarly journals Spatial-temporal variability of algal bloom in the Dnipro Reservoirs

2019 ◽  
pp. 18-27
Author(s):  
Viktor Vyshnevskyi
Keyword(s):  
Water Temperature ◽  
Algal Bloom ◽  
Remote Sensing Data ◽  
Water Area ◽  
Water Runoff ◽  
Water Colour ◽  
Small Water ◽  
The North ◽  
Large Water ◽  
Favorable Conditions

Using the remote sensing data, first of all, the data of Terra and Aqua satellites, the spatial-temporal patterns of algal bloom in the Dnipro Reservoirs were established. The greatest growth of algae is observed in the Kremenchuts’ke, the smallest — in the Kyivske reservoirs. The reasons for these patterns are formulated. In particular, the growth of algae in the Kyivske Reservoir, primarily in its northern part, is restricted with the significant water colour, the inflow of solid runoff and the relatively low water temperature. A smallest algal bloom during 2013–2018 was observed in 2013. It was caused with a rather large water runoff of the Dnipro River and with significant water colour as well. In addition, the increasing of algal bloom was negatively affected with a significant cloudiness in the second half of summer, when the of algal bloom usually is the greatest. The algal bloom was significant in 2015–2016, which was caused with small water runoff and small water colour. For 2013–2018 the dates of algal bloom beginning and maximum increasing of algae were established. This is usually observed in August when warm, and most importantly, sunny weather occurs. An abnormally late algal bloom was observed 19–22.09.2018, which was facilitated with the corresponding weather. It has been revealed that under favorable conditions, the view of water surface can change significantly during one day. Such rapid changes can not be caused by changes in water temperature, since they are not sharp in the reservoirs. The wind has a great impact on the distribution of algae by water area of the reservoirs. It is able to shift the zone with the largest bloom in any direction. The predominance of the north-eastern wind over the Kremenchuts’ke and Kam’yanske reservoirs in July-August leads to the fact that the greatest algal bloom is observed near their right south-western bank.

WATER RESOURCES OF THE LOWER DANUBE RIVER AND THEIR USE WITHIN THE TERRITORY OF UKRAINE

2020 ◽  
Author(s):  
V.I. Vyshnevskyi ◽  
◽  
S.A. Shevchuk ◽  
T.V. Matiash ◽  
◽  
...  
Keyword(s):  
Remote Sensing ◽  
Water Intake ◽  
Algal Bloom ◽  
Remote Sensing Data ◽  
Water Area ◽  
Danube River ◽  
Water Runoff ◽  
Sensing Data ◽  
Temporal Features ◽  
Warm Weather

The main hydrological characteristic of the Lower Danube River namely its water runoff and sediment yield are presented. Based on SRTM data the area of the river basin within the territory of Ukraine was determined. It is equal to 6454 km2. The basin areas of the largest rivers, flowing into the lakes of the Lower Danube River, were determined too. The features of their hydrochemical regime were studied as well. Based on the remote sensing data it was specified the water area of four largest lakes in this territory namely Kahul, Yalpuh-Kuhurluy, Katlabukh and Kytai. This area at normal water level is as follows: Kahul – 90.6, YalpuhKugurluy – 235, Katlabukh – 60.7, Kytai – 52.9 km2. Using the regular monitoring and remote sensing data, it was studied the water temperature and the ecological state of the lakes. It was evaluated the spatial and temporal features of algal bloom as well. The highest algal bloom is usually observed in August in sunny and warm weather. It was presented the data about the water management and water use on the researched territory. The largest water intake is from the Danube River, much less water intake is from the local lakes. The most of water is used for irrigation needs.

scholarly journals Morpholithodynamics of lagoonal straits of the North-Eastern Sakhalin

2019 ◽  
pp. 79-94
Author(s):  
V. V. Afanasev
Keyword(s):  
Additional Data ◽  
Three Dimensional ◽  
Remote Sensing Data ◽  
Water Area ◽  
The North ◽  
North Eastern ◽  
Geological Information ◽  
History Of ◽  
Three Dimensional Models ◽  
And Migration

The results of the analysis of geospatial and geological information on the structure and dynamics of the lagoon coast of the North-Eastern Sakhalin are presented. On the basis of a number of parameters of the coastal erosion-accumulation processes and migration of lagoon straits during the period 1927–2014. the morpholithodynamics system of the North-Eastern Sakhalin was considered. The volume of sediments transported during the migration of the straits, was estimated with the help of three-dimensional models, in which, parallel with time-averaged areas of erosion and accumulation, additional data were used, namely: bathymetry of the straits and adjacent water area, characteristics of the relief of the barrier forms and geological information obtained as a result of georadar survey and drilling. Georadar data, together with remote sensing data, have made it possible to create a model of sedimentation, which formed the basis for the analysis of the history of the coast formation beyond the period of observations. Currently, we can trace the situation as long as to the middle of the XIXth century.

scholarly journals Transmit the heat of rivers to surface seawater

2021 ◽  
Vol 276 ◽  
pp. 01010
Author(s):  
Dongfang Yang ◽  
Linzhen Wei ◽  
Ming Feng ◽  
Shengjun Zhang ◽  
Danfeng Yang
Keyword(s):  
Water Temperature ◽  
Coastal Waters ◽  
Seawater Temperature ◽  
Jiaozhou Bay ◽  
Water Area ◽  
Interval Length ◽  
Surface Seawater ◽  
Temperature Changes ◽  
The North ◽  
Temperature Area

Based on the survey materials of the waters of Jiaozhou Bay in April and August 1981, this article studies the water temperature and horizontal distribution in the surface waters of Jiaozhou Bay. The results have showed that the water temperature ranged within 7.52–30.90°C in April and August, and the length of interval of water temperature was 23.38°C. The water temperature of the ocean was above 7.00°C. It indicated that the water temperature of the entire water body of Jiaozhou Bay was relatively high in April and August, in terms of the changes of water temperature. In April, the water temperature in the water body of Jiaozhou Bay ranged within 7.52–13.70°C, and the length of temperature interval was 6.18°C. In Jiaozhou Bay, from the northeastern coastal waters along the northern coastal waters to the northwestern coastal waters, the range of water temperature changes was 12.82–13.70°C, and the interval length of seawater temperature changes was 0.88°C. From the northern area to the southern area, the range of water temperature changes was 7.52–13.70°C, and the interval length of seawater temperature was 6.18°C. In August, the range of water temperature changes was 24.60–30.90°C, and the interval length of seawater temperature was 6.30°C. In the eastern area of Jiaozhou Bay, the water temperature in the coastal waters of the estuary of Jiaozhou Bay was 30.90°C, forming a high temperature area. In the coastal waters of Jiaozhou Bay from the northwest to the north, the range of water temperature changes was 27.32–27.37°C and the interval length of seawater temperature was 0.05°C. In April and August, the increase of water temperature in the coastal waters from the northeast along the north to the northwest of Jiaozhou Bay was mainly caused by the shortwave radiation from the sun and sky and the longwave radiation from the atmosphere which continuously offered heat to the seawater. In April, it formed a circular water area with low temperature centered with the central water area of Jiaozhou Bay, whose water temperature ranged within 7.52–8.51°C. Thus, there was no heat source to provide heat to the central waters of Jiaozhou Bay, resulting a loop-locked low water temperature area in the center of the bay. In August, in the eastern part of Jiaozhou Bay, that is, the coastal waters in the estuary of Haibo River, the water temperature reached a relatively high value, 30.90°C. The source of the increase in water temperature was the transportation of heat from Haibo River, which transferred the heat of the river to the surface seawater.

MONITORING THE DYNAMICS OF THERMOABRASION COASTS AT KHARASAVEY AREA, WESTERN YAMAL (KARA SEA)

2017 ◽  
Author(s):  
Dmitry Kuznetsov ◽  
Dmitry Kuznetsov ◽  
Anatoliy Kamalov ◽  
Anatoliy Kamalov ◽  
Nataliya Belova ◽  
...  
Keyword(s):  
Human Impact ◽  
Remote Sensing Data ◽  
Kara Sea ◽  
Motor Vehicles ◽  
Yamal Peninsula ◽  
Western Coast ◽  
Frozen Ground ◽  
Coastal Dynamics ◽  
The North ◽  
Ice Content

The dynamics of thermoabrasion coasts on loose sediments under permafrost conditions are highly variable due to several factors: length of the dynamic period of the year, mechanic composition of the frozen ground and its ice content, hydrometeorological conditions, and human impact. Multiannual monitoring of the coastal zone was carried out by Lab. Geoecology of the North (Moscow State University) at the 22 km long Kharasavey deposit site, Western Coast of Yamal Peninsula (Kara Sea). The methods include direct measurements and observations (repeated topographic survey of shore transects from 1981 to 2012) along with remote sensing data analysis (images from 1964 to 2011). This allowed producing detailed characteristics of coastal dynamics. At the site, thermoabrasion coasts occupy the most part, and accumulative coasts are present in the north. Data on natural relief forming factors and ground composition are included in the detailed geomorphologic map of the site. Shore retreat rate shows correlation to amounts of wind-wave energy and to specific wind directions. Human impact on the coast includes dredging at the port channel, mining of sand, driving motor vehicles, and deposition of construction debris. Relations between shore retreat rate and aforementioned factors were studied, including dependencies on ice content, and shore segmentation was carried out. This allows for coastal dynamics forecasts in the region.

scholarly journals Phosphorous runoff risk assessment and its potential management using wollastonite according to geochemical modeling

2019 ◽  
Vol 4 (1) ◽  
pp. 787-794 ◽  
Author(s):  
Aneela Hayder ◽  
Stephen Vanderburgt ◽  
Rafael M. Santos ◽  
Yi Wai Chiang
Keyword(s):  
Risk Analysis ◽  
Algal Blooms ◽  
Agricultural Land ◽  
Algal Bloom ◽  
Risk Mitigation ◽  
Geochemical Modeling ◽  
Geochemical Modelling ◽  
Water Runoff ◽  
Phosphorus Pollution ◽  
Contaminate Drinking Water

AbstractLoss of phosphorus from agricultural land through water runoff causes serious detrimental effects on the environment and on water quality. Phosphorous runoff from excessive use of fertilizers can cause algal blooms to grow in nearby water systems, producing toxins that contaminate drinking water sources and recreational water. In this study, a risk analysis of the algal toxin micro-cystin-LR and the mitigation of phosphorus from agriculture runoff is discussed. A risk analysis was performed on the algal bloom toxin microcystin-LR considering the Lake Erie algal bloom event of 2011 as a case study. Toxicity risk analysis results show that relatively low concentrations of microcystin-LR compared to recent case studies pose an acute health risk to both children and adults, and a significant increase in the risk of developing cancer is suggested but subject to further study given the assumptions made. This study investigated the potential of using wollastonite to mitigate phosphorus pollution, considering thermodynamic conditions of a constructed wetland receiving influent water from agriculture runoff, by using geochemical modelling. Geochemical modelling results show that wollastonite can react with phosphorus and capture it in the stable mineral form of hydroxyapatite, offering a possible strategy for risk mitigation of phosphorous runoff. A removal efficiency of 77% of phosphorus using wollastonite is calculated with the help of geochemical modelling.

scholarly journals Spatial Pattern Change and Ecosystem Service Value Dynamics of Ecological and Non-Ecological Redline Areas in Nanjing, China

2021 ◽  
Vol 18 (8) ◽  
pp. 4224
Author(s):  
Minghui Yang ◽  
Yu Xie
Keyword(s):  
Spatial Pattern ◽  
Ecosystem Service ◽  
Remote Sensing Data ◽  
Water Area ◽  
Ecosystem Service Value ◽  
Bottom Line ◽  
Research Issues ◽  
Service Value ◽  
Ecological Protection ◽  
Ecological Conservation

Ecological conservation red line (ECRL) is gaining increasing academic attention as delimiting the minimum space scope of ecological protection and the bottom line of ecological security. Taking Nanjing as a case study, we divided the territory into ecological and non-ecological redline areas (ERAs and NERAs, respectively). This paper highlights two key research issues based on the 2005, 2010, 2015 and 2018 annual remote sensing data: (i) quantitative analysis of the Ecological Redline Policy (ERP) validity by conducting a horizontal comparison of the ERAs and NERAs; and (ii) exploration of the land-use transitions and spatial pattern changes affecting ecosystem service value (ESV). Results showed that delineating ECRL could effectively slow down the decline rate of ESV. The trend of eco-quality deterioration was greater than eco-quality improvement in Nanjing, presenting an ESV that declined slightly in the whole. According to our findings, we suggest that reasonably increasing eco-lands (woodland and water area) and decreasing construction land will enhance the regional ESV. Meanwhile, promoting the transition from production space to ecological space and depressing the encroachment of living space on other space types, will be instrumental in mitigating the ESV decline. The results of this study are expected to provide valuable implications for spatial planning and sustainable development in Nanjing.

scholarly journals Horizontal Movement of Fast Ice in the North Water Area

1977 ◽  
Vol 19 (81) ◽  
pp. 547-554 ◽  
Author(s):  
Hajime Ito ◽  
Fritz Müller
Keyword(s):  
Sea Ice ◽  
Water Area ◽  
Physical Characteristics ◽  
Stress Strain ◽  
Horizontal Movement ◽  
The North ◽  
North Water ◽  
Fast Ice ◽  
External Forces

AbstractThe understanding of the horizontal movement of fast ice is important for applied sea-ice mechanics. A case study, carried out in conjunction with a polynya known as North Water, is presented in this paper. The displacements of the fast-ire arches which separate the polynya from the surrounding ice-covered sea, were measured and found to be small. It is, therefore, confirmed that these arches prevent the influx of large quantities of sea ice into the polynya. The results are then explained in terms of the external forces (wind and current), the stress- strain situations and some physical characteristics (temperature and thickness) which were measured simultaneously.

scholarly journals Applications of Satellite Thermal Infrared Images for Monitoring North Water during the Periods of Polar Darkness

1980 ◽  
Vol 25 (93) ◽  
pp. 425-438
Author(s):  
B. Dey
Keyword(s):  
Satellite Images ◽  
Open Water ◽  
Thermal Infrared ◽  
Water Area ◽  
Infrared Images ◽  
Baffin Bay ◽  
The North ◽  
Thermal Infrared Images ◽  
North Water

AbstractThe study reported here illustrates the unique value of NOAA thermal infrared (TIR) images for monitoring the North Water area in Smith Sound and northern Baffin Bay during the periods of polar darkness. Wintertime satellite images reveal that, during the months of December through February, open water and thin ice occur in a few leads and polynyas. However, in March, the areas of open water and thin ice decrease to a minimum with a consequent higher concentration of ice. Two ice dams, in northern Kennedy Channel and in northern Smith Sound, regulate the flow of ice into northern Baffin Bay and also determine the areal variations of open water and thin ice in Smith Sound.

A massive summer-kill of the dog-whelk, Nucella lapillus, on the north Cornwall coast in 1995: freak or forerunner?

1999 ◽  
Vol 79 (1) ◽  
pp. 103-109 ◽  
Author(s):  
P.E. Gibbs ◽  
J.C. Green ◽  
P.L. Pascoe
Keyword(s):  
High Mortality ◽  
Laboratory Experiments ◽  
Algal Bloom ◽  
Extended Period ◽  
Littorina Littorea ◽  
Nucella Lapillus ◽  
Sewage Outfall ◽  
The North ◽  
Algal Toxicity ◽  
Calm Weather

In the summer of 1995 a massive kill of the dog-whelk, Nucella lapillus, occurred in Bude Bay on the north Cornish coast. High mortality was detectable along 12 km of shoreline. The only other intertidal species affected appeared to be another neogastropod, Ocenebra erinacea. The cause of the kill is unknown but the evidence suggests that it occurred in early July following an extended period of warm, calm weather in June. Possible causes of this event are discussed: algal toxicity may have been responsible since an algal bloom was detected offshore in July in the area. Laboratory experiments exposing gastropods to different species and concentrations of microalgae, designed to test whether N. lapillus is more sensitive than Monodonta lineata and Littorina littorea, gave inconclusive results. No comparable kill has occurred in the Bude area for at least 20 y, but it is suggested that nutrients from a newly-constructed, offshore sewage outfall may now stimulate local algal bloom development during calm weather periods.

scholarly journals Djankuat glacier station in the North Caucasus, Russia: a database of glaciological, hydrological, and meteorological observations and stable isotope sampling results during 2007–2017

2019 ◽  
Vol 11 (3) ◽  
pp. 1463-1481 ◽  
Author(s):  
Ekaterina P. Rets ◽  
Viktor V. Popovnin ◽  
Pavel A. Toropov ◽  
Andrew M. Smirnov ◽  
Igor V. Tokarev ◽  
...  
Keyword(s):  
Wind Speed ◽  
Precipitation Amount ◽  
Turbulent Fluxes ◽  
Water Runoff ◽  
North Caucasus ◽  
Time Step ◽  
Glacier Surface ◽  
The North ◽  
Meteorological Observations ◽  
The Impact

Abstract. This study presents a dataset on long-term multidisciplinary glaciological, hydrological, and meteorological observations and isotope sampling in a sparsely monitored alpine zone of the North Caucasus in the Djankuat research basin. The Djankuat glacier, which is the largest in the basin, was chosen as representative of the central North Caucasus during the International Hydrological Decade and is one of 30 “reference” glaciers in the world that have annual mass balance series longer than 50 years (Zemp et al., 2009). The dataset features a comprehensive set of observations from 2007 to 2017 and contains yearly measurements of snow depth and density; measurements of dynamics of snow and ice melting; measurements of water runoff, conductivity, turbidity, temperature, δ18O, δD at the main gauging station (844 samples in total) with an hourly or sub-daily time step depending on the parameter; data on δ18O and δ2H sampling of liquid precipitation, snow, ice, firn, and groundwater in different parts of the watershed taken regularly during melting season (485 samples in total); measurements of precipitation amount, air temperature, relative humidity, shortwave incoming and reflected radiation, longwave downward and upward radiation, atmospheric pressure, and wind speed and direction – measured at several automatic weather stations within the basin with 15 min to 1 h time steps; gradient meteorological measurements to estimate turbulent fluxes of heat and moisture, measuring three components of wind speed at a frequency of 10 Hz to estimate the impulse of turbulent fluxes of sensible and latent heat over the glacier surface by the eddy covariance method. Data were collected during the ablation period (June–September). The observations were halted in winter. The dataset is available from PANGAEA (https://doi.org/10.1594/PANGAEA.894807, Rets et al., 2018a) and will be further updated. The dataset can be useful for developing and verifying hydrological, glaciological, and meteorological models for alpine areas, to study the impact of climate change on hydrology of mountain regions using isotopic and hydrochemical approaches in hydrology. As the dataset includes the measurements of hydrometeorological and glaciological variables during the catastrophic proglacial lake outburst in the neighboring Bashkara valley in September 2017, it is a valuable contribution to study lake outbursts.

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