نتایج جستجو برای: fine sediment load

تعداد نتایج: 290264  

2013
E. EVANS A. C. WILCOX

Pulses of fine sediment in gravel-bedded rivers can cause extensive fine sediment infiltration (FSI) into void spaces in coarse bed material, potentially altering river morphodynamics and aquatic ecosystems. Previous work suggests a conceptual model of FSI whereby FSI occurs to a limited depth as a function of the relative grain size of bed sediment compared with infiltrating sediment and is in...

Extended abstract 1- Introduction The phenomena of erosion, sediment transport, and sedimentations have tremendously destructive effects on the environment and hydraulics structures. In general, the sediment transportation depends on river discharges, but the proposed equations inherited serious errors.  The estimation of suspended sediment load (SSL) is one of the most important factors in r...

2013
B. CAMENEN M. JODEAU M. JABALLAH

Three different methods to analyse fine sediment deposits on a gravel bar using pictures are presented in this paper. A manual digitization and deposits zone delineation are performed as well as two different automated procedures. The three methods are applied on aerial pictures taken in 2006 by a drone from a height around 150 m above the study site. Two other sets of pictures taken in 2010 ar...

1993
THOMAS E. LISLE

Gravel bed channels have a much greater capacity than sand bed channels to regulate the mobility of the bed surface through the formation of a surface layer of bed particles that is coarser than the particles supplied as load. The coarse surface layer affects bed mobility in two important ways. First, it reduces differences in mobility between coarser and finer particles on the bed surface by m...

Extended abstract 1- Introduction Evaluation is a process of assessing the degree of achievement to determined goals. In the meantime, choosing the right method for evaluating the effects will have a significant role on the results and management strategies. Therefore, considering the importance of check dams in watershed management programs in Iran, in this study, performance of check dams i...

2017
Kasper E. Brodersen Kathrine J. Hammer Verena Schrameyer Anja Floytrup Michael A. Rasheed Peter J. Ralph Michael Kühl Ole Pedersen

HIGHLIGHTS: Sedimentation of fine sediment particles onto seagrass leaves severely hampers the plants' performance in both light and darkness, due to inadequate internal plant aeration and intrusion of phytotoxic H2S. Anthropogenic activities leading to sediment re-suspension can have adverse effects on adjacent seagrass meadows, owing to reduced light availability and the settling of suspended...

2005
Lester J. McKee Neil K. Ganju David H. Schoellhamer

This study demonstrates the use of suspended-sediment concentration (SSC) data collected at Mallard Island as a means of determining suspended-sediment load entering San Francisco Bay from the Sacramento and San Joaquin River watersheds. Optical backscatter (OBS) data were collected every 15 min during water years (WYs) 1995–2003 and converted to SSC. Daily fluvial advective sediment load was e...

استاد عسگری, منصور , شفاعی بجستان, محمود ,

The application of “Modified Einstein Procedure” is recommended by the Specialized Committee on Sediment, Iranian Ministry of Energy. However, this method has not been applied to any river in the country. It is the purpose of this study to investigate the total sediment load of the Karun and Karkheh rivers at Ahwas and Hamidieh stations. The graphical calculations of the method are very complic...

1993
Sue Hilton Thomas E. Lisle

USDA Forest Service Res. Note PSW-RN-414-WEB. 1993. E xperienced hydrologists and geomorphologists can estimate the relative mobility of a streambed by looking at indicators of bedload transport, such as the freshness of bed-surface material. Another such indicator is the amount of fine sediment in pools. Pools in gravelbed streams commonly contain deposits of fine sediment (mostly sand and gra...

The variable and complex nature of the sediment load of rivers has led that the estimation of sediment entering the reservoirs and the production of long term sediment, for determining the lifetime of the structures encounter with the problem. Application of sediment rating curves is one of the most common methods for estimating the suspended sediment load of rivers. Regardless of the accuracy ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید