Fluvial Sedimentation in Southern Ontario

1975 ◽  
Vol 12 (11) ◽  
pp. 1813-1819 ◽  
Author(s):  
W. T. Dickinson ◽  
A. Scott ◽  
G. Wall
Keyword(s):  
Suspended Sediment ◽  
Drainage Density ◽  
Low Flow ◽  
Southern Ontario ◽  
Frequency Distributions ◽  
Sediment Yields ◽  
Sediment Loads ◽  
Fluvial Sedimentation ◽  
Sediment Data ◽  
Suspended Loads

Suspended sediment data for Southern Ontario stream have been analyzed with regard to areal and temporal patterns, characteristics of sediment concentrations, and relationships between sediment loads and watershed parameters. The range of annual suspended sediment yields for seven river basins is determined as 5250 to 175 000 kg/year/km2. The daily suspended loads exhibit highly skewed frequency distributions, with mean loads being equalled or exceeded less than 20% of the time and 50% of the annual load occurring during the months of March and April. It is demonstrated that sample loads collected during periods of low flow, and stream rankings determined from low flow data, are not indicative of the annual suspended sediment load picture. No simple model between suspended loads and such basin indices as relief ratio and drainage density is found to be satisfactory for prediction purposes.

scholarly journals Organic matter dynamics and stable isotope signature as tracers of the sources of suspended sediment

2012 ◽  
Vol 9 (6) ◽  
pp. 1985-1996 ◽  
Author(s):  
Y. Schindler Wildhaber ◽  
R. Liechti ◽  
C. Alewell
Keyword(s):  
Organic Matter ◽  
Suspended Sediment ◽  
Brown Trout ◽  
Arable Land ◽  
Atomic Ratio ◽  
High Flow ◽  
Low Flow ◽  
Organic C ◽  
Sediment Loads ◽  
Temporal And Spatial

Abstract. Suspended sediment (SS) and organic matter in rivers can harm brown trout Salmo trutta by affecting the health and fitness of free swimming fish and by causing siltation of the riverbed. The temporal and spatial dynamics of sediment, carbon (C), and nitrogen (N) during the brown trout spawning season in a small river of the Swiss Plateau were assessed and C isotopes as well as the C/N atomic ratio were used to distinguish autochthonous and allochthonous sources of organic matter in SS loads. The visual basic program IsoSource with 13Ctot and 15N as input isotopes was used to quantify the temporal and spatial sources of SS. Organic matter concentrations in the infiltrated and suspended sediment were highest during low flow periods with small sediment loads and lowest during high flow periods with high sediment loads. Peak values in nitrate and dissolved organic C were measured during high flow and high rainfall, probably due to leaching from pasture and arable land. The organic matter was of allochthonous sources as indicated by the C/N atomic ratio and δ13Corg. Organic matter in SS increased from up- to downstream due to an increase of pasture and arable land downstream of the river. The mean fraction of SS originating from upper watershed riverbed sediment decreased from up to downstream and increased during high flow at all measuring sites along the course of the river. During base flow conditions, the major sources of SS are pasture, forest and arable land. The latter increased during rainy and warmer winter periods, most likely because both triggered snow melt and thus erosion. The measured increase in DOC and nitrate concentrations during high flow support these modeling results. Enhanced soil erosion processes on pasture and arable land are expected with increasing heavy rain events and less snow during winter seasons due to climate change. Consequently, SS and organic matter in the river will increase, which will possibly affect brown trout negatively.

scholarly journals Classifications of runoff and sediment data to improve the rating curve method

2017 ◽  
Vol 48 ◽  
Author(s):  
Hossein Khaledian ◽  
Homayoun Faghih ◽  
Ata Amini
Keyword(s):  
Suspended Sediment ◽  
River Flow ◽  
Data Classification ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Low Flow ◽  
Rating Curve ◽  
Sediment Rating Curve ◽  
Curve Method ◽  
Sediment Data

In this study, data classification method was evaluated to increase accuracy of estimating suspended sediment load. To achieve this objective, suspended sediment in Chehelgazi and Khalifeh-Tarkhan rivers in Kurdistan, Iran, were estimated using Sediment Rating Curve (SRC) method in three different approaches of data classification. At first, measured data were modeled without classification. Then, data based on flow statues were divided into two series as high and low flow. Eventually, based on sediment concentration, the data were divided into low and high sediment concentration. Long-term runoff and sediment data were used to calibrate rating curve model. The estimated values were compared with recorded data and the performances of these models were evaluated using statistical criteria. The results indicated an effective role of data classification to improve estimating sediment transportation by rating curve method. In one of the stations, it was observed that due to classification based on river flow and sediment concentration, model efficiency was increased about 45% and 28%, respectively. Furthermore, in case of improving efficiency of SRC method, classifying data based on flow statues was found to be more effective than sediment concentration. The results of this study can be used to improve the management of the basin by more accurately estimating the amount of suspended sediments transporting in the rivers draining to reservoirs.

scholarly journals Copula-Based Infilling Methods for Daily Suspended Sediment Loads

Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1701
Author(s):  
Jenq-Tzong Shiau ◽  
Yu-Cheng Lien
Keyword(s):  
Suspended Sediment ◽  
Conditional Distribution ◽  
Sediment Load ◽  
Distribution Model ◽  
Rating Curve ◽  
Similar Frequency ◽  
Sediment Rating Curve ◽  
Sediment Loads ◽  
Recorded Data ◽  
Sediment Data

Less-frequent and inadequate sampling of sediment data has negatively impacted the long and continuous records required for the design and operation of hydraulic facilities. This data-scarcity problem is often found in most river basins of Taiwan. This study aims to propose a parsimonious probabilistic model based on copulas to infill daily suspended sediment loads using streamflow discharge. A copula-based bivariate distribution model of sediment and discharge of the paired recorded data is constructed first. The conditional distribution of sediment load given observed discharge is used to provide probabilistic estimation of sediment loads. In addition, four different methods based on the derived conditional distribution of sediment load are used to give single-value estimations. The obtained outcomes of these methods associated with the results of the traditional sediment rating curve are compared with recorded data and evaluated in terms of root mean square error (RMSE), mean absolute percentage error (MAPE), Nash-Sutcliffe efficiency (NSE), and modified Nash-Sutcliffe efficiency (MNSE). The proposed approach is applied to the Janshou station located in eastern Taiwan with recorded daily data for the period of 1960–2019. The results indicate that the infilled sediments by the sediment rating curve exhibit better performance in RMSE and NSE, while the copula-based methods outperform in MAPE and MNSE. Additionally, the infilled sediments by the copula-based methods preserve scattered characteristics of observed sediment-discharge relationships and exhibit similar frequency distributions to that of recorded sediment data.

scholarly journals Organic matter dynamics and stable isotopes for tracing sources of suspended sediment

2012 ◽  
Vol 9 (1) ◽  
pp. 453-483 ◽  
Author(s):  
Y. Schindler Wildhaber ◽  
R. Liechti ◽  
C. Alewell
Keyword(s):  
Organic Matter ◽  
Suspended Sediment ◽  
Brown Trout ◽  
Arable Land ◽  
Atomic Ratio ◽  
High Flow ◽  
Low Flow ◽  
Organic C ◽  
Erosion Processes ◽  
Sediment Loads

Abstract. Suspended sediment (SS) and organic matter in rivers can harm brown trout Salmo trutta by impact on health and fitness of free swimming fish and siltation of the riverbed. The later results in a decrease of hydraulic conductivity and therefore smaller oxygen supply to the salmonid embryos. Additionally, oxygen demand within riverbeds will increase as the pool of organic matter increases. We assessed the temporal and spatial dynamics of sediment, carbon (C) and nitrogen (N) during the brown trout spawning season and used C isotopes as well as the C/N atomic ratio to distinguish autochthonous and allochthonous sources of organic matter in SS loads. The visual basic program IsoSource with 13Ctot and 15N as input isotopes was used to quantify the sources of SS in respect of time and space. Organic matter fractions in the infiltrated and suspended sediment were highest during low flow periods with small sediment loads and lowest during high flow periods with high sediment loads. Peak values in nitrate and dissolved organic C were measured during high flow and precipitation probably due to leaching from pasture and arable land. The organic matter was of allochthonous sources as indicated by the C/N atomic ratio and δ13Corg. Organic matter in SS increased from up- to downstream due to pasture and arable land. The fraction of SS originating from upper watershed riverbed sediment increased at all sites during high flow. Its mean fraction decreased from up- to downstream. During base flow conditions, the major sources of SS are pasture and arable land. The later increased during rainy and warmer periods probably due to snow melting and erosion processes. These modeling results support the measured increased DOC and NO3 concentrations during high flow.

Sediment and nutrient loadings to Lake Ontario: methodological arguments

1977 ◽  
Vol 14 (7) ◽  
pp. 1555-1565 ◽  
Author(s):  
Edwin D. Ongley ◽  
John G. Ralston ◽  
Richard L. Thomas
Keyword(s):  
Suspended Sediment ◽  
Sediment Load ◽  
Lake Ontario ◽  
Environmental Issues ◽  
Surveillance Data ◽  
Nutrient Loads ◽  
Suspended Sediment Load ◽  
Sampling Strategies ◽  
Sediment Loads ◽  
Sediment Data

Environmental issues frequently require values for sediment and nutrient loads in river systems. Except in rare instances, such values must be drawn from existing surveillance data which may not reflect sampling strategies pertinent to the issue at hand. In particular, the time variant and nonlinear relationships between discharge and both suspended sediment and sediment-related parameters such as phosphorus cannot be captured in detail by surveillance data, Nevertheless, such data collected routinely by the Ontario Ministry of the Environment accurately reflect the relative loadings both in terms of unit and total yields in five basins where detailed suspended sediment data are available. Although surveillance data underestimate the absolute values of suspended sediment loads calculated from detailed sediment information, these data do capture the relative monthly and seasonal contributions to annual suspended sediment load. A comparison of three methods for calculating annual unit and total loadings of suspended and solute components from surveillance information indicates that annual mean data convey information which is not significantly less adequate than monthly aggregations of data.

scholarly journals Analyses of suspended sediment loads in Slovenian rivers

2016 ◽  
Vol 61 (6) ◽  
pp. 1094-1108 ◽  
Author(s):  
Nejc Bezak ◽  
Mojca Šraj ◽  
Matjaž Mikoš
Keyword(s):  
Suspended Sediment ◽  
Sediment Loads
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