scholarly journals Suspended sediment yield characteristics variability in rivers of Kamchatka krai

Author(s):  
L. V. Kuksina

The regularities of spatiotemporal variability of suspended sediment yield characteristics were studied. Based on the analysis of difference-integral yield curves, it was found that most of the rivers in Kamchatka krai are characterized by the presence of two relatively long trends in the suspended sediment yield variability: an increase until the end of the 1970s–early 1980s, and its subsequent decrease. This regularity disturbs in rivers under the influence of volcanic eruptions, where the most significant increasing of sediment yield is observed after major eruptions. Existent maps of mean annual suspended sediment concentration and mean annual specific suspended sediment yield were significantly specified (18 instead 4 and 13 instead two zones were marked respectively). The map of grain-size distribution of suspended sediment was compiled (three zones was marked in region under study). Maximum values of mean annual specific suspended sediment yield (more than 500 t km-2 yr-1), suspended sediment concentration (more than 1000 g m-3) and grain-size of sediments are observed in water runoff of volcanic areas. Minimum values of suspended sediment concentration, specific suspended sediment yield, as well as grain-size of sediments characterized the mainland part of the krai.

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1451 ◽  
Author(s):  
Ludmila Kuksina

This study investigates the spatial and temporal variability of water runoff and suspended sediment yield in rivers in the Kamchatsky Krai territory (in the Far East of the Russian Federation). It is based on data from 269 monitoring stations for the period of hydrometeorological observations (1930–2015). The representativeness and the homogeneity of data on water runoff and suspended sediment yield was examined. Regions with prescribed limits of specific water discharge (L·s−1·km−2) and suspended sediment concentration (mg·L−1) variability were selected in the Kamchatsky Krai territory. Most rivers in this region are characterized by two relatively long trends in these characteristics that increased from the late 1970s to the early 1980s, followed by a subsequent decline (until 2015). Kamchatsky Krai includes 9 specific water discharge and 18 suspended sediment concentration regions. Hydrometeorological data of three zonal types of water runoff and corresponding suspended sediment concentration distribution were described, and five azonal types of water regime were characterized. One of these types was characterized by a nearly uniform distribution of water runoff within the year, due to the predominance of groundwater feeding source, while the rest of them had mixed feeding. The present study is the first study to describe the water regime of rivers on volcanic flanks in the Kamchatsky Krai.


Author(s):  
Ludmila V. Kuksina

Abstract. Key factors of sediment yield formation and variability in the Kamchatsky Krai are relief characteristics and climate (especially precipitation). The last research in climate change in Kamchatka demonstrates climate warming – mean annual air temperature has increased on 1.5 ∘C during the period from 1951 to 2009 in average (the maximum increase was revealed in the west of Kamchatka and in the Kamchatka River valley, the minimum one – in the extreme south and north). Decrease of annual precipitation was observed at the same period. In addition frequency and intensity of precipitation is growing. Thereby described climate changes in Kamchatka influence on sediment yield characteristics directly (influence of precipitation on surface washout formation) and indirectly (through water runoff and hydrological regime of rivers changes). Analysis of spatio-temporal variability in suspended sediment yield demonstrated decrease since late 1970–early 1980 in the most part of rivers in the Kamchatsky Krai. Revealed fluctuations demonstrate very good coincidence with precipitation amount variability. Decrease of precipitation leads to corresponding diminution of rainfall erosive factor in the territory which is the key factor of suspended sediment yield formation and variability in rivers in the Kamchatsky Krai. The value of reduction varies from 1 % to 45 % and involves decrease of erosion rates in the territory. Thereby climate change influences on suspended sediment yield in multiple-valued way. Income of friable volcanic deposits on the catchment surface is the key factor of suspended sediment yield formation and variability in some river basins under the impact of volcanic eruptions, and in combination with raising precipitation it can lead to catastrophic increase of sediment yield.


2013 ◽  
Vol 17 (11) ◽  
pp. 4641-4657 ◽  
Author(s):  
S. B. Morera ◽  
T. Condom ◽  
P. Vauchel ◽  
J.-L. Guyot ◽  
C. Galvez ◽  
...  

Abstract. Hydro-sedimentology development is a great challenge in Peru due to limited data as well as sparse and confidential information. This study aimed to quantify and to understand the suspended sediment yield from the west-central Andes Mountains and to identify the main erosion-control factors and their relevance. The Tablachaca River (3132 km2) and the Santa River (6815 km2), located in two adjacent Andes catchments, showed similar statistical daily rainfall and discharge variability but large differences in specific suspended-sediment yield (SSY). In order to investigate the main erosion factors, daily water discharge and suspended sediment concentration (SSC) datasets of the Santa and Tablachaca rivers were analysed. Mining activity in specific lithologies was identified as the major factor that controls the high SSY of the Tablachaca (2204 t km2 yr−1), which is four times greater than the Santa's SSY. These results show that the analysis of control factors of regional SSY at the Andes scale should be done carefully. Indeed, spatial data at kilometric scale and also daily water discharge and SSC time series are needed to define the main erosion factors along the entire Andean range.


2013 ◽  
Vol 1 (No. 1) ◽  
pp. 23-31 ◽  
Author(s):  
Bečvář Martin

Sediment is a natural component of riverine environments and its presence in river systems is essential. However, in many ways and many places river systems and the landscape have been strongly affected by human activities which have destroyed naturally balanced sediment supply and sediment transport within catchments. As a consequence a number of severe environmental problems and failures have been identified, in particular the link between sediments and chemicals is crucial and has become a subject of major scientific interest. Sediment load and sediment concentration are therefore highly important variables that may play a key role in environment quality assessment and help to evaluate the extent of potential adverse impacts. This paper introduces a methodology to predict sediment loads and suspended sediment concentrations (SSC) in large European river basins. The methodology was developed within an MSc research study that was conducted in order to improve sediment modelling in the GREAT-ER point source pollution river modelling package. Currently GREAT-ER uses suspended sediment concentration of 15 mg/l for all rivers in Europe which is an obvious oversimplification. The basic principle of the methodology to predict sediment concentration is to estimate annual sediment load at the point of interest and the amount of water that transports it. The amount of transported material is then redistributed in that corresponding water volume (using the flow characteristic) which determines sediment concentrations. Across the continent, 44 river basins belonging to major European rivers were investigated. Suspended sediment concentration data were collected from various European basins in order to obtain observed sediment yields. These were then compared against the traditional empiric sediment yield estimators. Three good approaches for sediment yield prediction were introduced based on the comparison. The three approaches were applied to predict annual sediment yields which were consequently translated into suspended sediment concentrations. SSC were predicted at 47 locations widely distributed around Europe. The verification of the methodology was carried out using data from the Czech Republic. Observed SSC were compared against the predicted ones which validated the methodology for SSC prediction.


2018 ◽  
Author(s):  
Jérémy Lepesqueur ◽  
Renaud Hostache ◽  
Núria Martínez-Carreras ◽  
Emmanuelle Montargès-Pelletier ◽  
Christophe Hissler

Abstract. Hydromorphodynamic models are powerful tools to predict the potential mobilization and transport of sediment in river ecosystems. Recent studies even showed that they are able to satisfyingly predict suspended sediment matter concentration in small river systems. However, modelling exercises often neglect suspended sediment properties (e.g. particle site distribution and density), even though such properties are known to directly control the sediment particle dynamics in the water column during rising and flood events. This study has two objectives. On the one hand, it aims at further developing an existing hydromorphodynamic model based on the dynamic coupling of TELEMAC-3D (v7p1) and SISYPHE (v7p1) in order to enable an enhanced parameterisation of the sediment grain size distribution with distributed sediment density. On the other hand, it aims at evaluating and discussing the added-value of the new development for improving sediment transport and riverbed evolution predictions. To this end, we evaluate the sensitivity of the model to sediment grain size distribution, sediment density and suspended sediment concentration at the upstream boundary condition. As a test case, the model is used to simulate a flood event in a small scale river, the Orne River in North-eastern France. The results show substantial discrepancies in bathymetry evolution depending on the model setup. Moreover, the sediment model based on an enhanced sediment grain size distribution (10 classes) and with distributed sediment density outperforms the model with only two sediment grain size classes in terms of simulated suspended sediment concentration.


Author(s):  
L. Kuksina ◽  
N. Alexeevsky

Abstract. Research into the spatial and temporal variability of suspended sediment flux (SSF, t year−1) has been conducted for rivers in the Kamchatka Krai (in the far east of the Russian Federation). The study of long-term fluctuations in SSF was based on difference-integral curve analysis. Most of the rivers in the region are characterized by two relatively long-term trends in SSF; increases from the late 1970s to the early 1980s, followed by a subsequent decline. Kamchatka was divided into regions based on similar conditions of specific suspended sediment yield (SSSY, t km−2 year−1) followed by a determination of the various factors controlling it. New maps of suspended sediment concentration (SSC, mg L−1) and SSSY for Kamchatka also were constructed and, based on this study, there currently appear to be 18 SSC and 13 SSSY regions, as opposed to 4 and 2 regions, respectively, as had been determined in the 1970s. The influence of volcanoes on SSF can be substantial, and can increase up to 5-fold after eruptions; SSC can reach 6∙105 mg L−1 in rivers draining the flanks of volcanoes.


Sign in / Sign up

Export Citation Format

Share Document