The present volume features fifty-seven papers presented at the international symposium «Suspended matter in rivers and estuaries» held at Reinbek, Germany, March 21--25, 1994. The contributions cover all aspects of particulate matter in aquatic environments. Topics span a wide range and can be divided in five principal groups: composition and properties of particulates, spatial and temporal variations of the distribution of particulate matter (scaling effects), particle-solute interactions, particle dynamics and transport processes and, as the result of the above processes,impact of particles and their absorbed load on the environment. Particulates in aquatic ecosystems are a complex phenomenon which demands to be approached multidisciplinarily, especially for the studies of rivers with variable water discharges and irregular flood events that perturb their particulate load and composition temporarily. At their estuaries, complexities are compounded by the effects of mixing of river water with tidal waters which change salinity and influence particle budget, size distribution and composition in space and time. Not only abiotic processes such as erosion, sedimentation and resuspension of inorganic particles brought about by the hydrographic forces, but also biological processes, like bacterial and algal aggregations on the particles, organic coating of the particle surfaces, colonization of the particles with heterotrophic organisms like Flagellates, Ciliates, Amoeba, Rotatoria and so forth, such forming microbiocoenoses on the flocs, numerous different biological activities and many more items are characterizing these complex aggregates. It is known that some fraction of nutrients but also toxic substances (e. g. pesticides) are bound to suspended particulate matter. Insight into the transport/precipitation mechanisms of these «hitchhiker» substances can hence only be gained by thorough understanding of particulate matter transport itself.

Preface VII Acknowledgements VII Composition and properties of particulates WALLING, D.E.: Suspended sediment transport by rivers: a geomorphological and hydrological perspective (Keynote lecture) (with 16 figures and 5 tables) 1- 27 LANGEDAL, M., OTTESEN, R.T. & BOGEN, J.: Time variation in the chemical composition of sediment in three Norwegian rivers - natural and anthropogenic causes (with 6 figures and 5 tables) 29- 39 NIEDERGESÄSS, R., EDEN, H. & SCHNIER, C.: Trace element concentrations in suspended particulate matter fractionated according to the settling velocity (with 5 figures and 3 tables) 41- 52 WILTSHIRE, K.H., GEISSLER, C.-D., SCHROEDER, F. & KNAUTH, H.-D.: Pigments in suspended matter from the Elbe estuary and the German Bight: their use as marker compounds for the characterisation of suspended matter and in the interpretation of heavy metal loadings (with 6 figures) 53- 63 GRESIKOWSKI, S., GREISER, N. & HARMS, H.: Distribution and activity of nitrifying bacteria at two stations in the Ems estuary (with 8 figures) 65- 76 TEN BRINKE, WILFRED B.M.: The impact of primarily produced organic matter on the aggregation of suspended sediment (with 10 figures and 2 tables) 77- 91 KIES, L., FAST, T., WOLFSTEIN, K. & HOBERG, M.: On the role of algae and their exopolymers in the formation of suspended particulate matter in the Elbe estuary (Germany) (with 10 figures and 2 tables) 93-103 MALCHOW, H. & SIMON, J.: Non-linear dynamics and transport of interacting species in a model estuary 105- 111 ELSTER, M., BOGEN, J. & OTTESEN, R. T.: Sediment transport, depositional proceses and particle bound elements on the Vagavatn delta, Norway (with 3 figures and 1 table) 113 -119 WITTE, G. & KÜHL, H.: Facilities for sedimentation and erosion measurements (with 4 f igures) 121 - 125 SPOTT, D. & GUHR, H.: The dynamics of suspended solids in the tidally unaffected area of the river Elbe as a function of flow and shipping (with 6 figures) 127-133 HOBERG, M. & NEUGEBOHRN, L.: Characterization of suspended particulate matter of the Elbe estuary (with 5 figures) 135-139 SCHÄFER, B. & HARMS, H.: Occurrence of different ammonia-oxidizing bacteria in the river Elbe between Hamburg and Gluckstadt (with 5 figures) 141 - 148 SOWITZKI, S., SOBOTTKA, M. & HARMS, H.: The importance of suspended particulate matter for distribution and survival of fecal coliform bacteria in the River Elbe near Hamburg (with 6 figures) 149-155 MERCIER, P, ROBERT, M., PENVEN, M.-J., ELSASS, F., JAUNET, A.-M., MUXART, T. & LAGADEC, E.: A methodology to study particulate matter (with 11 figures) 157- 167 Spatial and temporal variation of particulate matter including scale effects SYMADER, W.: Factors controlling riverine sediment associated chemistry (Keynote lecture) (with 3 figures) 169 - 177 VAN LEUSSEN, W.: Erosion/sedimentation cycles in the Ems estuary (with 9 figures and 1 table) 179-193 GRABEMANN, I., KAPPENBERG, J. & KRAUSE, G.: Comparison of the dynamics of the turbidity maxima in two coastal plain estuaries (with 6 figures and 1 table) 195-205 FANGER, H.-U., AMANN, V., BROCKMANN, C., BROCKMANN, U., GEGE, P., HERBERS, D., JABLONSKI, R., KAPPENBERG, J., PRANGE, A. & RYBACZOK, P.: Spatial and tidal distributions of suspended particulate matter along the lower Elbe river - first results from a joint venture including airborne remote sensing, helicopter and shipborne investigations: BILEX' 93 (with 11 figures) 207-219 KOENIG, P. & FROHSE, A.: Dynamics and transport processes of suspended particulate matter in the German Bight (with 6 figures) 221-228 BERL, R., SYMADER, W., GASPARINI, F., HAMPE, K. & UDELHOFEN, TH.: Particle associated contaminants in flowing waters - the role of sources (with 2 figures) 229-234 NIEDERGESÄSS, R., PRANGE, A. & SCHNIER, C.: Variations of trace element content in suspended particulate matter in the Elbe estuary (with 7 figures) 235-246 O'RIORDAN, C.A., MONISMITH, S.G. & KOSEFF, J.R.: The effects of near-bed hydrodynamics on model bivalve filtration rates (with 5 figures and 1 table) 247-254 SAAD, M.A.H. & HASSAN, E.M.: Distribution of suspended matter, as well as particulate iron and manganese in the Rosetta estuary of the Nile and the adjacent Mediterranean waters (with 6 figures and 3 tables) 255-269 Solutes/solids interactions FÖRSTNER, U.: Solutes/solids interactions of metals in estuaries (Keynote lecture) (with 9 figures and 4 tables) 271-287 VAN BEUSEKOM, J.E.E. & DE JONGE, VN.: Seasonal cycle in the interaction of suspended matter with dissolved aluminium and iron in the Ems estuary (with 5 figures) 289-293 PETERSEN, W., HONG, J., WTLLAMOWSKI, C. & WALLMANN, K.: Release of trace contaminants during reoxidation of anoxic sediment slurries in oxic water (with 9 figures and 2 tables) 295-305 CORTESAO, C. & VALE, C.: Seasonal and inter-annual variations of particulate metals in a river contaminated with mine drainage (Sado River, Portugal) (with 4 figures and 2 tables) 307-314 SCHMITT, J., GU, B., SCHORER, M., FLEMMING, H.-C. & MCCARTHY, J.J.: The role of natural organic matter as a coating on iron oxide and quartz (with 4 figures) 315-322 Dynamics and transport processes KAPPENBERG, J., SCHYMURA, G., KUHN, H. & FANGER, H.-U.: Spring-neap variations of suspended sediment concentration and transport in the turbidity maximum of the Elbe estuary (with 7 figures) 323-332 PENNDORF, K., JUSTIN, J. & KRÜGER, A.: Transport of suspended particulate matter in the Elbe estuary - parametrization of findings from the BILEX-campaign of spring 1990 (with 5 figures and 3 tables) 333-341 MÜLLER, A. & PULS, W.: Modelling of suspended matter transport in tidal rivers (with 7 figures) 343-351 MALCHEREK, A., MARKOFSKY, M. & ZELKE, W.: Numerical modelling of settling velocity variations in estuaries (with 9 figures) 353-362 LAU, Y.L.: Modelling cohesive sediment settling (with 5 figures and I table) 363-371 WESTRICH, B. & DREHER, TH.: Numerical compartment model for contaminant sediment mobility description in rivers (with 10 figures and 2 tables) 373-380 PULS, W. & KÜHL, H.: A settling tube for measuring suspended matter settling velocities in the German Bight (with 7 figures and 1 table) 381-388 PROCHNOW, D., ENGELHARDT, CH. & BUNGARTZ, H.: On the settling velocity distribution of suspended sediments in the Spree River (with 10 figures and 2 tables) 389-400 ALBERTS, J. J. & GRIFFIN, CH.: Formation of particulate organic carbon (POC) from dissolved organic carbon (DOC) in salt marsh estuaries of the southeastern United States (with 5 figures) 401-409 UNCLES, R.J. & STEPHENS, J.A.: Seasonal variability of fine-sediment in the Tamar estuary (with 1 figure and 1 table) 411 -414 JULIEN, P.Y.: Sand particle interaction in moving bed layers (with 2 figures and I table) 415-420 SIVAKUMARAN, K., ROSSELLI, A.T. & BALLOFFET, A.: Particulate matter transport in the proposed Sea Level Canal, Panama (with 11 figures and 4 tables) 421 -438 ROSS, J. & KROHN, J.: Computation of suspended matter in a Wadden Sea bight (Konigshafen, Sylt) (with 10 figures) 439-447 GALAS, J.: Depositional processes and suspension of particulate organic matter in a high mountain stream above the timber line (with 5 figures and 1 table) 449-454 KERN, U. & WESTRICH, B.: Sediment dynamics in a lock-regulated section of the Neckar river, Germany (with 3 figures and 1 table) 455-460 EDELVANG, K.: A study of the significance of flocculation for the in situ settling velocities of suspended particles in a tidal channel (with 6 figures) 461-467 ENGELHARDT, CH., BUNGARTZ, H., THIELE, M., KRÜGER, A. & PROCHNOW, D.: Settling behavior of particulate matter in a slow flow section of a Spree River branch (with 6 figures and 1 table) 469-473 NEHLS, R., GREISER, N. & HARMS, H.: Changes in amount and composition of suspended particulate matter in relation to river discharge in the River Elbe near Hamburg Harbour, indicating changing transport characteristics (with 12 figures) 475-484 ODUYEMI, K.: Sediment transport in the Tamar estuary (with 4 figures) 485-490 ENGGROB, H.G. & OLESON, K.W.: A hybrid sediment transport modelling system for rivers and estuaries (with 3 figures and I table) 491-495 SEIBT-WINCKLER, A. & SCHIRMER, F.: Measurements with a three frequency echo sounder for the detection of suspended matter in a river estuary (with 10 figures) 497-506 HAMM, A., GLASSMANN, M. & LEPELT, A.: Transport of particulate matter in an Alpine river (River Salzach) and its importance for river ecology (with 6 figures and 2 tables) 507-513 Environmental impacts HOROWITZ, A.J.: Spatial and temporal variations in suspended sediment and assoiated trace elements - requirements for sampling, data interpretation, and the determination of annual mass transport (Keynote lecture) (with 14 figures and 4 tables) 515-536 FOSTER, I. D. L., CHARLESWORTH, S.M. & PROFFITT, S.B.: Sediment-associated heavy metal distribution in urban fluvial and limnic systems; a case study of the River Sowe, U.K. (with 2 figures and 4 tables) 537-545 FERREIRA, A.M. & VALE, C.: The differences of PCB and lipid levels between settling/resuspended materials and surface sediments of the Sado estuary (with 3 figures and 3 tables) 547-552 BOTZAN, D., TOMOTAGA, G. & BOTZAN, T.: Environmental effects of alluvial trans- port over the Romanian Danube sector and its catchment area (with 2 figures) 553-556 SINGH, R.B. & PANDEY, B.W.: Environmental monitoring of particulate matter and pollution in major rivers of India (with 1 figure and 2 tables) 557-561 YANG, W.: Distribution of metals, causal factors and areal sampling in the Urumqi area, northwestern China (with 2 figures and 2 tables) 563-569 List of participants 571-573