The survival of Escherichia coli in bottom sediment (Lake Onalaska, navigation pool no. 7, Mississippi River) was studied by using in situ dialysis culture of sterile (autoclaved) and unsterile sediment samples. Bags made from dialysis tubing were filled with either course sand sediment (28.8% fine) or organic, silty clay sediment (77.2% fine) and placed at the sediment-water interface. Bags re...

We use the concentration of in situ Be in quartz isolated from fluvial and morainal sand to trace sediment sources and to determine the relative contribution of glacerized and deglaciated terrain to Greenland’s sediment budget. We sampled along the western, eastern, and southern margins of the Greenland Ice Sheet, and collected sediment sourced from glacerized (n=19) and non-glacerized terrain ...

[1] The paleoceanographic recording fidelity of pelagic sediments is limited by chemical diagenesis and physical mixing (bioturbation and horizontal sediment transport). Diagenesis and bioturbation are relatively well-studied, but the effects of physical sedimentation have been largely ignored. Modeling U series isotopes (e.g., Th) can potentially quantify horizontal sediment movement, but mode...

The importance of initial sediment conditions on model calibration and validation is analysed. A sediment model was calibrated and validated under three different initial sediment conditions: (0) no sediment availability, (1) calibration of the initial sediment condition and (2) using a warm-up simulation. The model results were assessed in terms of the graphic of fine sediment transport, or se...

The biomass of sediment organisms can be measured by a.llowing carbon tracer to distribute itself through sediment cores. Application of this method to sediment from Marion lake, British Columbia, indicated that most of the sediment microorganisms were concentrated in the top 2 cm of sediment, where the total biomass of microorganisms was estimated to be 183IJ.g C/cm2• The radiotracer estimate ...

B the concentration of “reactive” biogenic silica per volume of sediment (mol cm) C the pore-water silicate concentration (mol cm) Cs the pore-water asymptotic silicate value observed at depth in the sediment column (mol cm) DB sediment bioturbation coefficient (cm yr) Ds the molecular diffusion coefficient for silicate in the seabed corrected for tortuosity effects (cm of sediment y) k the dis...

Several types of sediment transport equations have been developed for estimation of the river sediment materials during the past decades. The estimated sediment from these equations is very different, especially when they applied for a specific river. Therefore, choice of an equation for estimation of the river sediment load is not an easy task. In this study 10 important sediment transport equ...

Small watershed sediment yield data were evaluated for eight small watersheds ranging from 35.2 to 159.5 ha within the United States Department of Agriculture – Agricultural Research Service Walnut Gulch Experimental Watershed (WGEW) in southeastern Arizona, USA. Stock pond sediment accumulation measurements covering time periods from 30 to 47 years were combined with water level records and es...

by far, different models for determining the relationship between the flow rate  and amount of precipitation have been developed. many models are based on regression models with limited assumptions. one of the most common methods for estimating  sediment of rivers is sediment rating curve. for better estimation of the amount of sediment based of sediment curve  rating equation, it is possible t...