This data set is the observation data of dongzhuanggou (non governance) in Nanxiaohegou watershed of Loess Plateau Gully Region from 2004 to 2010. Dongzhuanggou (non treatment ditch) is a small branch of Nanxiaohegou watershed, with a drainage area of 1.15km2. Dongzhuanggou remains in its original state. This data set mainly includes precipitation observation data of dongzhuanggou rainfall station and runoff and sediment observation data of dongzhuanggou runoff station
Precipitation: the precipitation observation instruments include SM1 ordinary rain gauge with diameter of 20cm and dsj-2 siphon self recording rain gauge. SM1 adopts 8:00 and 20:00 two-stage system for annual observation, mainly observing the beginning and ending time of precipitation, and counting the precipitation. When the intermittent time of precipitation is more than 15 minutes, it is recorded as two precipitation observations, and when the intermittent time is less than 15 minutes, it is regarded as a precipitation observation record. If a precipitation crosses 8:00 and 20:00, it should be measured at 8:00 and 20:00. Dsj-2 adopts 24 segment system for flood season observation. In case of failure of self recording rain gauge, the observation data of ordinary rain gauge are used to supplement. Observation of runoff and sediment: (1) water level observation: the water gauge is set in the middle of the weir channel, and the flood observation in flood season and non flood season is the same. In flood period or period of rapid water level change, under the premise of controlling the water level at the important turning points of rise and fall, peak top, leveling 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 at a single peak It is required to observe every peak, valley and complete water level change process from 30min to 1.0h after leveling. (2) Sediment Observation: 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 and the sediment concentration changes sharply, the measurement times need to be increased appropriately. Generally, water samples are collected at the flow measuring section, and the horizontal sampler is used for sampling. During the period of clear water, no water sample is taken. The water sample is treated by displacement method. A calibrated 500ml pycnometer is used. An analytical balance with an accuracy of 1 / 1000g is used. The minimum sand weight is not less than 1.0g.
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.2020.93
10.12072/ncdc.HWXFZhan.db0008.2020
