The results of runoff scouring experiments show that the relationship between unit width runoff energy consumption and uint width sediment production is Dr=18.672 (ΔE-0.751). The parameter of soil anti-erodibility is 18.672 g/J and the critical energy consumption is 0.751 J/(ms).

The unit width runoff energy consumption increased with the flow discharge increasing but changed in parabola form. The critical slope is between 21 and 24. The energy consumption in the upper section of the steep slope increased with the discharge of flow and slope and decreased in the middle section of the slope but stable in low section.

The possessed energy of unit width discharge is direct proportion with the cube of ratio of original slope width B to width b after runoff concentrated.

The correlations between the hydrodynamic factors of slope flow (including the discharge, flow energy consumption per unit width, flow shear stress, stream power and unit stream power) and soil detachment rate are experimentally studied in a flume. The width of the flume is 100cm, the gradient of the slope is ranging from 3° to 30° and the flow discharge is varied from 2.5l/min to 6.5l/min.

Results by energy consumption implied that there was also linear relation between sediment transportation and energy consumption of unit runoff width: Dr=14.61(ΔE-0.37), which indicated that soil erodibility was 14.61 g/J, with critical energy consumption of 0.37 J/(min·cm).

There were similar trends in both observed data and the calculated data by unit runoff power theory,which changed with slope like parabola,and the maximum data appeared at 21° slope.

On the slope of 3°～21°,the average runoff consumption increases with slope,and decreases with slope when the slope gradient is over the critical gradient(21°～24°).

In central-north area, unit depth runoff yield is highly pertinent to it, the following factor is soil moisture before rainfall, other factors' role is confined by grotto erode.

Application of the maximum width of the grid and flow rate per unit width of the river results in the number of flow zones in the lateral direction of the river.

The peel strength is the first peak force per unit width of bondline required to produce progressive separation, and the peel energy is the amount of energy per unit bonding area associated with a crack opening.

Estimates of cross-reef mass transport per unit width ranged from 0.058 to 0.032?m2s?-1.

In the strip packing problem (a standard version of the two-dimensional cutting stock problem), the goal is to pack a given set of rectangles into a vertical strip of unit width so as to minimize the total height of the strip needed.

It is shown that any plane set of constant unit width contains a semi-circle of radius 1/2, and using this a minimal univeral plane cover is explicitly constructed.

A method for determining the quantity of erosion and moving was discussed in the paper. Duriny erosion the main cause of the variation of moving ratio was the "filling of low-lying lands" in the sloping fields. Contral experiments were conducted on moving of different lengths of slope. It was found that the maximum of runoff ratio Per unit width and the maximum of sand carrying Per unit width sand could be used to discriminate the variation of erosion and moving.Areas of "erosion-moving" erosion-heaping - moving"...

A method for determining the quantity of erosion and moving was discussed in the paper. Duriny erosion the main cause of the variation of moving ratio was the "filling of low-lying lands" in the sloping fields. Contral experiments were conducted on moving of different lengths of slope. It was found that the maximum of runoff ratio Per unit width and the maximum of sand carrying Per unit width sand could be used to discriminate the variation of erosion and moving.Areas of "erosion-moving" erosion-heaping - moving" and " erosion - moving interference"were divided. An exponent function equation for small water sheds was regressed according to the data of moving ratio, length of slope and size of slope.

The relationship for hydro dynamic parameters (flow regime, flow velocity, depth and friction factor) as a function of flow discharge and slope gradient was simulated by means of flume experiments. The results demonstrate that when flow depth is less than 0.316 cm, the flow is transitional flow. The flow change to turbulent when flow depth is large than 0.316cm. The flow velocity and depth are mainly controlled by flow discharge, simple linear function can be used for mean velocity and flow depth predicting....

The relationship for hydro dynamic parameters (flow regime, flow velocity, depth and friction factor) as a function of flow discharge and slope gradient was simulated by means of flume experiments. The results demonstrate that when flow depth is less than 0.316 cm, the flow is transitional flow. The flow change to turbulent when flow depth is large than 0.316cm. The flow velocity and depth are mainly controlled by flow discharge, simple linear function can be used for mean velocity and flow depth predicting. Slope gradient has no significant impact on both flow velocity and depth and has influence on friction factor at low flow discharge. However, as discharge increasing, the friction factor will be controlled by discharge again. All these results reveal that there is larger difference exiting in hydrodynamic properties between overland flow and open channel flow, and should be full considered in water erosion mechanism analyzing and model building.

Firstly, Methods to measure soil erosion and sediment delivery were introduced when The methods were used to calculate the ratio of sediment delivery. With different condition of rain and land utilization, Soil erosion can be calculated through measuring the sediment at the exit transect of the plot (20 meters long and 5 meters wide); sediment delivery can be gained through measuring the sediment reserving at the exit of runoff plot or small water collection area which slope length is more than 20 meters. Then...

Firstly, Methods to measure soil erosion and sediment delivery were introduced when The methods were used to calculate the ratio of sediment delivery. With different condition of rain and land utilization, Soil erosion can be calculated through measuring the sediment at the exit transect of the plot (20 meters long and 5 meters wide); sediment delivery can be gained through measuring the sediment reserving at the exit of runoff plot or small water collection area which slope length is more than 20 meters. Then After 45 group data from runoff plot 30, 40 and 60 meters long, slope gradient 9% for 9 years were analysed, rate of the minimum runoff unit width and the maximum sediment may use to discriminate the comparative relationship between erosion and sediment delivery, e.g. the ratio of sediment delivery. According to these parameter , the erosive delivery status was divided in to three patterns: erosion-delivery plot erosion-sediment trap-delivery plot and erosion-de livery and disturbance plot. The formula for the critical value among the different plot is pmax - 11. 96 + 0. 117qmin and qmin - 8. 187ρmax - 85. 676。 By measuring sediment delivery from different area (0.5hm2 -41.3hm2) and slope length (30m-965m) water-collected plots and comparing erosion amount from standard plot, sediment delivery ratio was obtained. Equation between sediment delivery ratio (SDR ) and slope length or water-collected area is SDR = 2.85L-0.306 or SDR = 0.735A-0.151 , The equation is convenient for rapid calculating SDR. Finally, effects of vegelation cover, soil moisture and mans activity and other fators on the sediment delivery ratio were also discussed.