Knowledge of Suspended Sediments Dynamics (SSD) across spatial scales is relevant for several fields of hydrology, such as eco-hydrological processes, the operation of hydrotechnical facilities and research on varved lake sediments as geoarchives. Understanding the connectivity of sediment flux between source areas in a catchment and sink areas in lakes or reservoirs is of primary importance to these fields. Lacustrine sediments may serve as a valuable expansion of instrumental hydrological records for flood frequencies and magnitudes, but depositional processes and detrital layer formation in lakes are not yet fully understood. This study presents a novel buoy system designed to continuously measure suspended sediment concentration and relevant boundary conditions at a high spatial and temporal resolution in surface water bodies. The buoy sensors continuously record turbidity as an indirect measure of suspended sediment concentrations, water temperature and electrical conductivity at up to nine different water depths. Acoustic Doppler current meters and profilers measure current velocities along a vertical profile from the water surface to the lake bottom. Meteorological sensors capture the atmospheric boundary conditions as main drivers of lake dynamics. It is the high spatial resolution of multi-point turbidity measurements, the dual-sensor velocity measurements and the temporally synchronous recording of all sensors along the water column that sets the system apart from existing buoy systems. Buoy data collected during a 4-month field campaign in Lake Mondsee demonstrate the potential and effectiveness of the system in monitoring suspended sediment dynamics. Observations were related to stratification and mixing processes in the lake and increased turbidity close to a catchment outlet during flood events. The rugged buoy design assures continuous operation in terms of stability, energy management and sensor logging throughout the study period. We conclude that the buoy is a suitable tool for continuous monitoring of suspended sediment concentrations and general dynamics in fresh water bodies.
References
[1]
Navratil, O.; Legout, C.; Gateuille, D.; Esteves, M.; Liebault, F. Assessment of intermediate fine sediment storage in a braided river reach (southern French Prealps). Hydrol. Process. 2010, 24, 1318–1332.
[2]
Di Cesare, G.; Schleiss, A.; Hermann, F. Impact of Turbidity Currents on reservoir sedimentation. J. Hydraul. Eng. 2001, 127, 6–16.
[3]
Walling, D.E. Tracing suspended sediment sources in catchments and river systems. Sci. Total Environ. 2005, 344, 159–184.
[4]
Duvert, C.; Gratiot, N.; Némery, J.; Burgos, A.; Navratil, O. Sub-daily variability of suspended sediment fluxes in small mountainous catchments-implications for community-based river monitoring. Hydrol. Earth Syst. Sci. 2011, 15, 703–713.
[5]
Francke, T.; Mamede, G.; López-Tarazón, J.A.; Batalla, R.J. Assessment of Sediment Yield and Reservoir Siltation Using Non-Parametric Regression and Numerical Modelling. Proceedings of European Geosciences Union General Assembly, Vienna, Austria, 13–18 April 2008. EGU2008-06723.
[6]
Evrard, O.; Némery, J.; Gratiot, N.; Duvert, C.; Ayrault, S.; Lefèvre, I.; Poulenard, J.; Prat, C.; Bonté, P.; Esteves, M. Sediment dynamics during the rainy season in tropical highland catchments of central Mexico using fallout radionuclides. Geomorphology 2010, 124, 42–54.
[7]
Viseras, C.; Fernández, J.; García-García, F.; Soria, J.M.; Calvache, M.L.; Jáuregui, P. Dynamics of sedimentary environments in the accelerated siltation of a reservoir: The case of Alhama de Granada, southern Spain. Environ. Geol. 2009, 56, 1353–1369.
[8]
Pimentel, D.; Harvey, C.; Resosudarmo, P.; Sinclair, K.; Kurz, D.; McNair, M.; Crist, S.; Sphritz, L.; Fitton, L.; Saffouri, R.; et al. Environmental and economic costs of soil erosion and conservation benefits. Science 1995, 267, 1117–1123.
[9]
Padhy, M.K.; Saini, R.P. Study of silt erosion on performance of a Pelton turbine. Energy 2011, 36, 141–147.
[10]
Pringle, C. Hydrologic connectivity and the management of biological reserves: A global perspective. Ecol. Appl. 2001, 11, 981–998.
[11]
Tetzlaff, D.; Soulsby, C.; Bacon, P.J.; Youngson, A.F. Connectivity between landscapes and riverscapes—A unifying theme in integrating hydrology and ecology in catchment science? Hydrol. Process. 2007, 21, 1385–1389.
[12]
Duvert, C.; Gratiot, N.; Anguiano-Valencia, R.; Némery, J.; Mendoza, M.E.; Carlón-Allende, T.; Prat, C.; Esteves, M. Baseflow control on sediment flux connectivity: Insights from a nested catchment study in Central Mexico. Catena 2011, 87, 129–140.
[13]
Foster, I.D.L.; Lees, J.A.; Owens, P.N.; Walling, D.E. Mineral magnetic characterization of sediment sources from an analysis of lake and floodplain sediments in the catchments of the old mill reservoir and slapton ley, south devon, UK. Earth Surf. Process. Landf. 1998, 703, 685–703.
[14]
Dearing, J. 90: Lake Sediments as Records of Past Catchment Response. In Encyclopedia of Hydrological Sciences, 1st ed.; Anderson, M., McDonnell, J.J., Eds.; Wiley: Chichester, UK, 2005; pp. 1355–1366.
[15]
Swierczynski, T.; Brauer, A.; Lauterbach, S.; Martin-Puertas, C.; Dulski, P.; von Grafenstein, U.; Rohr, C. A 1600 yr seasonally resolved record of decadal-scale flood variability from the Austrian Pre-Alps. Geology 2012, 40, 1047–1050.
[16]
Czymzik, M.; Dulski, P.; Plessen, B.; von Grafenstein, U.; Naumann, R.; Brauer, A. A 450 year record of spring-summer flood layers in annually laminated sediments from Lake Ammersee (southern Germany). Water Resour. Res. 2010, 46, 1–16.
[17]
Boehrer, B.; Schultze, M. Stratification of lakes. Rev. Geophys. 2008, 46, 1–27.
[18]
Ma, C.; Wu, D.; Lin, X. Variability of surface velocity in the Kuroshio Current and adjacent waters derived from Argos drifter buoys and satellite altimeter data. Chin. J. Oceanol. Limnol. 2009, 27, 208–217.
[19]
Marti, C.L.; Mills, R.; Imberger, J. Pathways of multiple inflows into a stratified reservoir: Thomson Reservoir, Australia. Adv. Water Resour. 2011, 34, 551–561.
[20]
Fernandez, D.M.; Meadows, L.A.; Vesecky, J.F.; Teague, C.C.; Paduan, J.D.; Hansen, P. Surface current measurements by HF radar in freshwater lakes. IEEE J. Ocean. Eng. 2000, 25, 458–471.
[21]
Navratil, O.; Evrard, O.; Esteves, M.; Legout, C.; Ayrault, S.; Némery, J.; Mate-Marin, A.; Ahmadi, M.; Lefèvre, I.; Poirel, A.; et al. Temporal variability of suspended sediment sources in an alpine catchment combining river/rainfall monitoring and sediment fingerprinting. Earth Surf. Process. Landf. 2012, 37, 828–846.
[22]
Susfalk, R. B.; Heyvaert, A.; Mihevc, T.; Fitzgerald, B.; Taylor, K. Linking On-shore and Near-shore Processes: Near-Shore Water Quality Monitoring Buoy at Lake Tahoe; Desert Research Institute: Reno, NV, USA, 2009.
[23]
Garel, E.; Nunes, S.; Neto, J.M.; Fernandes, R.; Neves, R.; Marques, J.C.; Ferreira, ó. The autonomous Simpatico system for real-time continuous water-quality and current velocity monitoring: Examples of application in three Portuguese estuaries. Geo-Mar. Lett. 2009, 29, 331–341.
[24]
Wilson, D. The Chesapeake Bay Interpretive Buoy System□: Recent Expansion and Advances. Proceedings of OCEANS 2009, MTS/IEEE Biloxi—Marine Technology for Our Future: Global and Local Challenges, Biloxi, MS, USA, 26–29 October 2009; pp. 1–5.
[25]
Consi, T.R.; Anderson, G.; Barske, G.; Bootsma, H.; Hansen, T.; Janssen, J.; Klump, V.; Paddock, R.; Szmania, D.; Waples, J.T. Measurement of Spring Thermal Stratification in Lake Michigan with the GLUCOS Observing System. Proceedings of OCEANS 2009, MTS/IEEE Biloxi—Marine Technology for Our Future: Global and Local Challenges, Biloxi, MS, USA, 26–29 October 2009; pp. 1–5.
[26]
Alcantara, E.H.; Novo, E.; Stech, J.; Lorenzzetti, J.; Barbosa, C.; Assireu, A.; Souza, A. A contribution to understanding the turbidity behaviour in an Amazon floodplain. Hydrol. Earth Syst. Sci. 2010, 14, 351–364.
[27]
Mueller, D.S.; Abad, J.D.; Garcia, C.M.; Gartner, J.W.; Garcia, M.H.; Oberg, K.A. Errors in acoustic Doppler profiler velocity measurements caused by flow disturbance. J. Hydraul. Eng. 2007, 133, 1411–1420.
[28]
Lewis, J. Turbidity-controlled suspended sediment sampling for runoff-event load estimation. Water Resourc. Res. 1996, 32, 2299–2310.
[29]
Holdaway, G.P.; Thorne, P.D.; Flatt, D.; Jones, S.E.; Prandle, D. Comparison between ADCP and transmissometer measurements of suspended sediment concentration. Cont. Shelf Res. 1999, 19, 421–441.
[30]
Dokulil, M. Seasonal and spatial distribution of cryptophycean species in the deep, stratifying, alpine lake Mondsee and their role in the food web. Hydrobiologia 1988, 161, 185–201.
Livingstone, D.M.; Dokulil, M.T. Eighty years of spatially coherent austrian lake surface temperatures and their relationship to regional air temperature and the North Atlantic Oscillation. Limnol. Oceanogr. 2001, 46, 1220–1227.
[33]
Thies, H.; Nickus, U.; Mair, V.; Tessadri, R.; Tait, D.; Thaler, B.; Psenner, R. Unexpected response of high Alpine Lake waters to climate warming. Environ. Sci. Technol. 2007, 41, 7424–7429.
[34]
Moss, B. Conservation problems in the norfolk broads and rivers of East Anglia, England-Boats and the causes of turbidty. Biol. Conserv. 1977, 12, 95–114.
[35]
Lewis, J.; Eads, R. Implementation Guide for Turbidity Threshold Sampling: Principles, Procedures, and Analysis; United States Department of Agriculture-Forest Service-Pacific Southwest Research Station: Lafayette, OR, USA, 2009; pp. 1–96.
[36]
Navratil, O.; Esteves, M.; Legout, C.; Gratiot, N.; Nemery, J.; Willmore, S.; Grangeon, T. Global uncertainty analysis of suspended sediment monitoring using turbidimeter in a small mountainous river catchment. J. Hydrol. 2010, 398, 246–259.
[37]
Righetti, M.; Toffolon, M.; Lucarelli, C.; Serafini, M. Sediments as tracers for transport and deposition processes in peri-alpine lakes: A case study. J. Hydrol. 2011, 411, 1–11.
[38]
Lambert, A.; Giovanoli, F. Records of riverborne turbidity currents and indications of slope failures in the Rhone Delta of Lake Geneva. Limnol. Oceanogr. 1988, 33, 458–468.
[39]
Dokulil, M.; Skolaut, C. Succession of phytoplankton in a deep stratifying lake: Mondsee, Austria. Hydrobiologia 1986, 138, 9–24.
[40]
Ferencik, B.M. Forschungsbericht 1996-1997-1. Teil MONDSEE; Oesterreichische Akademie der Wissenschaften: Mondsee, Austria, 1997; pp. 1–32.
[41]
Boehrer, B.; Ilmberger, J.; Münnich, K.O. Vertical structure of currents in western Lake Constance. J. Geophys. Res. 2000, 105, 28823–28835.
[42]
Kostaschuk, R.; Best, J.; Villard, P.; Peakall, J.; Franklin, M. Measuring flow velocity and sediment transport with an acoustic Doppler current profiler. Geomorphology 2005, 68, 25–37.
[43]
Hsü, K.J.; Kelts, K. Swiss lakes as a geological laboratory. Naturwissenschaften 1985, 72, 315–321.
[44]
Sturm, M.; Matter, A. Sedimente und Sedimentationsvorg？nge im Thunersee. Eclogae. Geol. Helv. 1972, 65, 563–591.
