Stream sedimentation concerns might probably be incorporated into the road design process as a simplified, intuitive thumbnail model. Road Density (RD) and Stream Crossing Density (SCD) however guide designers towards minimizing minor, unused spur roads that have minimal sediment impacts. Crossing Area Served (CAS) on the other hand, focuses design attention towards the most heavily traveled se...

The paper examines sediment yield and its response to catchment disturbance and environmental variables in the Upper Ž . Yangtze basin, where the attention of environmentalists has been drawn to the Three Gorges Project TGP . Information about the source and conveyance of sediment from the catchment area to the Three Gorges Reservoir has implications for management strategies. Methodologies for...

Variations of suspended sediment concentration over ripples in regular waves were described using an existing numerical model system. Nielsen’s (1992) empirical formula for sediment entrainment rate from the bed surface was used with an additional scale factor in the model system. The model system was applied to two typical laboratory experimental conditions selected for description of the vari...

The objectives of this research program are 1) to characterize the structure of the river plumes and coastal currents in the western Adriatic Sea and their influence on sediment dispersal from Alpine and Appenine rivers; 2) to assess the relative contributions of Alpine and Apennine rivers to the clinoform development in the Adriatic, and to determine the delivery mechanisms of these different ...

Recent advances in monitoring technology have enabled high frequency, in-situ measurements of total phosphorus and total reactive phosphorus to be undertaken with high precision, whilst turbidity can provide an excellent surrogate for suspended sediment. Despite these measurements being fundamental to understanding the mechanisms and flow paths that deliver these constituents to river networks,...

The relative contributions of sediment resuspension and external nutrient loading to seasonal fluctuations of the total nitrogen to total phosphorus (TN : TP) ratio in the water column of the shallow Kirkkojärvi basin were studied. In May, the TN : TP mass ratio was above 30, but it decreased to below 10 in July–August. In October, the ratio increased again. Water quality was regulated by exter...

DNA complex has been widely used as non-viral vectors for the delivery of genes or siRNA. Owing to the strong and long-ranged electrostatic interaction, the structure and property of the DNA complex should evolve with time in a long-term. To test this hypothesis, we choose 2000 bp double-stranded DNA and 21 bp oligonucleotide as the model molecules, and comparatively studied their complexation ...

Sediment, which is central as a sink for organic material and nutrient cycling, provides habitat for feeding, resting, and nesting of sea cucumbers in aquaculture systems. We conducted a 2 mo experiment to investigate the optimal sea mud to sand ratios in sediment for sea cucumber Apostichopus japonicus (Selenka, 1867) aquaculture. Sea mud (<0.08 mm) and sand (0.08−0.5 mm) were used to prepare ...

In recent years growing human pressure on agricultural land in the north of the Lao PDR has led to accelerated degradation processes along hillslopes, and higher sediment delivery rates to streams. Furthermore, high demand from urban centres is attracting farmers to cultivate vegetables in riparian areas. These land-use changes may have negative affects on stream water quality. The aims of this...