scholarly journals DYNAMICS OF SPRING RUNOFF FLUCTUATIONS FOR THE RIVERS OF THE DON AND DNIEPER BASINS IN THE BELGOROD REGION

Author(s):  
Andrey Kornilov ◽  
Vladimir Reshetnikov ◽  
Evgeniya Kornilova ◽  
Maria Lebedeva
Keyword(s):  
2004 ◽  
Vol 5 (6) ◽  
pp. 1076-1090 ◽  
Author(s):  
Kevin Werner ◽  
David Brandon ◽  
Martyn Clark ◽  
Subhrendu Gangopadhyay

Abstract This study compares methods to incorporate climate information into the National Weather Service River Forecast System (NWSRFS). Three small-to-medium river subbasins following roughly along a longitude in the Colorado River basin with different El Niño–Southern Oscillation signals were chosen as test basins. Historical ensemble forecasts of the spring runoff for each basin were generated using modeled hydrologic states and historical precipitation and temperature observations using the Ensemble Streamflow Prediction (ESP) component of the NWSRFS. Two general methods for using a climate index (e.g., Niño-3.4) are presented. The first method, post-ESP, uses the climate index to weight ensemble members from ESP. Four different post-ESP weighting schemes are presented. The second method, preadjustment, uses the climate index to modify the temperature and precipitation ensembles used in ESP. Two preadjustment methods are presented. This study shows the distance-sensitive nearest-neighbor post-ESP to be superior to the other post-ESP weighting schemes. Further, for the basins studied, forecasts based on post-ESP techniques outperformed those based on preadjustment techniques.


Author(s):  
Sabine Mellman-Brown ◽  
Dave Roberts ◽  
Bruce Pugesek

The hydrology of the Snake River in Grand Teton National Park is partly determined by releases from Jackson Lake Dam. The dam was first built in 1908 and became part of the National Park system GTNP was expanded to include most of Jackson Hole. Completion of the present structure of Jackson Lake Dam occurred in 191 7 and resulted in an increase above the natural level of Jackson Lake of 11.9 m. The Bureau of Reclamation (BOR) manages the dam and sets discharge schedules, primarily to meet agricultural needs, and to a lesser extent the needs of recreational river use. Major changes to the hydrological regime of the Snake River include lower than natural peak releases, decrease in frequency of extreme flood events, and unusually high flows from July to September. In addition, peak releases prior to 1957 were not synchronized with spring runoff but shifted to July or early August. Changes in inundation frequencies of floodplains, inundation duration and timing of peak flows have profound effects on the extent and composition of the riparian zone.


Author(s):  
A.I. Petelko ◽  

The materials of scientific research for a number of years on the formation of melt water runoff on autumn plowing with stock-regulating forest belts of a combined design with low-growing shrubs are presented. It was revealed that the spring runoff depends on the main natural factors: moisture, soil freezing and snow deposition.


2021 ◽  
pp. 117-127
Author(s):  
M. V. GEORGIEVSKY ◽  
◽  
N. I. GOROSHKOVA ◽  
V. A. KHOMYAKOVA ◽  
A. V. STRIZHENOK

The article presents an analysis of the impact of climate change on the main characteristics of ice phenomena, snow cover and the water regime in the Small Northern Dvina River basin occurring in recent decades. Recently, a significant climate warming has been observed in the basin. As a result, winters are getting warmer and shorter. There is also an increase in winter precipitation and the number of thaws. Climate warming directly affects the duration of snow cover, which decreases both due to the later formation and to the earlier destruction of snow. There is also a slight downward trend in the annual values of the maximum snow water equivalent, which may be the result of an increase in the number of thaws in winter, when a part of the snow cover melts contributing to the winter river runoff. The analysis of the main characteristics of the ice cover on the rivers of the studied basin shows that their changes are similarly to changes in the snow cover: there is a reduction in the freeze-up period due to its later formation and earlier complete destruction. The maximum ice thickness on the rivers of the basin also tends to decrease. There is an increase in winter and a decrease in spring runoff. Predictive estimates of changes in the observed trends in the future are presented in the fi nal part of the article based on the CMIP5 project data.


1992 ◽  
Vol 16 ◽  
pp. 225-230 ◽  
Author(s):  
Richard Kattelmann ◽  
Yang Daqing

Although less than 100 mm of precipitation generally falls during the winter months in the upper Ürümqi River basin, an uneven snowpack of 20 to 100 cm depth is present in early spring. When the surface of this snow cover begins to melt in April, the meltwater is not immediately transformed into streamflow. Several processes are responsible for the five to 15 days of delay in streamflow generation: refreezing in the snow cover itself, creation of a basal ice layer at the snow-soil interface, growth of superimposed ice on the glaciers of the basin, ice formation in stream channels and restoration of high albedo by snowstorms that occur about once a week in spring.


2009 ◽  
Vol 66 (7) ◽  
pp. 1153-1168 ◽  
Author(s):  
Clint C. Muhlfeld ◽  
Thomas E. McMahon ◽  
Durae Belcer ◽  
Jeffrey L. Kershner

We used radiotelemetry to assess spatial and temporal spawning distributions of native westslope cutthroat trout ( Oncorhynchus clarkii lewisi ; WCT), introduced rainbow trout ( Oncorhynchus mykiss ; RBT), and their hybrids in the upper Flathead River system, Montana (USA) and British Columbia (Canada), from 2000 to 2007. Radio-tagged trout (N = 125) moved upriver towards spawning sites as flows increased during spring runoff and spawned in 29 tributaries. WCT migrated greater distances and spawned in headwater streams during peak flows and as flows declined, whereas RBT and RBT hybrids (backcrosses to RBT) spawned earlier during increasing flows and lower in the system. WCT hybrids (backcrosses to WCT) spawned intermediately in time and space to WCT and RBT and RBT hybrids. Both hybrid groups and RBT, however, spawned over time periods that produced temporal overlap with spawning WCT in most years. Our data indicate that hybridization is spreading via long-distance movements of individuals with high amounts of RBT admixture into WCT streams and stepping-stone invasion at small scales by later generation backcrosses. This study provides evidence that hybridization increases the likelihood of reproductive overlap in time and space, promoting extinction by introgression, and that the spread of hybridization is likely to continue if hybrid source populations are not reduced or eliminated.


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