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Anthropogenic changes in the suspended..

particularly in its upper stretch. The resultant increase in the volume of the reservoir, which continues, has stopped a decreasing trend in the trap efficiency for suspended load. The (5 parameter has increased for the last 10 years, a fact reflected in the decreasing amounts of the suspended load outflow from the reservoir (Fig. 9).

Fig. 9. Increasing rates of the suspended load outflow, O^, from chosen dam reservoirs indicat-ing lowering trap efficiency, P, for suspended matter in shallowed reservoirs. Locations of the reservoirs are: the Rożnów Reservoir on the middle stretch of the Dunajec River, the Włocławek Reservoir on the Lower Vistula, and the Dębe Reservoir on the lower stretch of the Narew (for distribution of the reservoirs within the river basin see Fig. 1). Intensive dredging practices in the Włocławek Reservoir started after 1982 are followed by an increased ratę of trap

efficiency for suspended load, P

CURRENT RATES OF SUSPENDED LOAD TRANSPORTATION AND SEDIMENTATION ALONG THE VISTULA

1. Auerage rates of suspended load transportation. As a result of an intensive sediment supply from the strong denudation of the Carpathians, the average rates of suspended load in the Yistula generally increase