This data set is the runoff and sediment observation data of four runoff stations in Nanxiaohegou watershed of Loess Plateau from 1981 to 1990. The experimental observation sections of runoff stations are Bacher weir and triangular groove weir, and the observation method is manual observation. It mainly includes daily average discharge data, daily average sediment concentration data, daily average sediment transport rate data, extracted data of flood hydrological elements, and successive flood test results data.
Water level observation: the base flow in flood season and non flood season is observed at fixed time, and the base flow in non flood season is observed in two sections, that is, once at 8:00 and 20:00; in flood season, base flow is observed in 4-stage system, i.e. 2:00, 8:00, 14:00 and 20:00 respectively, and the flood season is from June to September. In flood period or rapid water level change period, under the premise of reading and controlling the water level at the important turning points of rise and fall, peak top, fall level and other water level fluctuation, the measurement times are roughly evenly arranged according to the water level change, with no less than 3 times near the peak, and no less than 11 times for a single peak. The observation shall be conducted once from 30 min to 1.0 h after leveling, so that the peak, valley and complete water level change process can be measured. Sediment Observation: the water side one point method is used to collect sediment manually. The principle of sediment sampling times in flood period is to control the change process of sediment concentration. When the water and sediment peaks are inconsistent or the sediment concentration changes sharply, the measurement times should be increased appropriately. All water samples were treated by displacement method
(1) Discharge calculation: the discharge is calculated by the observed water level. The calculation formula for the outlet stations of shibamutai and Huaguoshan reservoirs is as follows: q = 3.7h1.59; Yangjiagou triangular groove weir: q = 4.9h2.4; dongzhuanggou triangular groove weir: q = q = 4.8h2.55 Q: Discharge, unit: m3 / S; H: water level, unit: M. (2) Calculation of sediment concentration: P = WS / V * 1000 calculation of sediment concentration, P: measured sediment concentration, unit: kg / m3; V: volume of water sample, unit: cm 3; WS: dry sand weight in water sample, unit: G.
In the process of compilation and input of observation data, there are four levels of manual verification, including tabulation, primary calibration, recheck and audit, so as to ensure the data quality.
This work is licensed under
CC BY 4.0 (Creative Commons Attribution 4.0 International License).
CSTR:11738.11.ncdc.HWXFZhan.2020.56
10.12072/ncdc.HWXFZhan.db0025.2020
