Automatic measurement of surface runoff at the plot scale

HIGHLIGHTS

Prototypes with a tipping bucket system were developed and calibrated

The equipment automatically measures surface runoff

The resolution of the devices can reach 5 L pulse ^-1.

The equipment is capable of monitoring flows of up to 80 L min ^-1.

The equipment is inexpensive and easy to build and maintain.

ABSTRACT

Although the hydrological importance of water infiltration into the soil and surface runoff is well known, manual measurement of these processes, especially at the plot and hillslope scales, is laborious and requires a trained team. This study aimed to develop prototypes with the tipping bucket principle for the automatic monitoring of surface runoff at a plot scale (14.5 × 3 m). In total, 18 prototypes were built and installed in an experiment with different soil covers. Aspects of the construction, calibration, operation and maintenance of the prototypes were reported in this study. Prototypes showed a satisfactory ability to monitor surface runoff with flow rates up to ~80 L min^-1. The devices have an adjustable resolution of up to 5 L pulse^-1, and they are inexpensive, easy to construct and simple to maintain. Although designed for a specific plot size (43.5 m²), the equipment can be adapted to smaller or larger plots by adjusting the volume of the tipping chambers. The proposed systems allow greater practicality in conducting experiments to monitor water loss through surface runoff at the plot scale and provide more detailed recordings of information.

 datalogger; erosion; hydrograph; tipping bucket; water infiltration