The Significance of Implementing Flow Monitoring in Ecological River Channels

　　Lakes themselves do not face ecological flow issues, as aquatic flora and fauna naturally arise, grow, and reproduce in accordance with the habitats of rivers and lakes. However, over the long term, as human demand for water—both within and outside river‑lake systems—has continued to rise, the water volumes upon which natural ecosystems depend have been steadily diverted, giving rise to what is known as an ecological… River flow monitoring Question.

　　China’s ecological flow management encompasses climate, river topography and geomorphology, the stage of regional economic and social development and its economic structure, river and lake governance, the construction and operation of reservoirs and hydropower stations, the effectiveness of social governance, as well as research on foundational theories and computational methods. This is an exceedingly complex issue that calls for systematic study, targeted policy measures, and strengthened ecological regulation and oversight. Next, we will discuss a real-time monitoring scheme for ecological river flows, aimed at understanding patterns of riverine change and advancing research on ecological flow issues.

　　In most small and medium-sized rivers in China, flow‑rate monitoring typically relies on conventional propeller‑type current meters and the float‑method to measure velocity, followed by the velocity‑area method to convert velocity into discharge—processes that impose significant operational challenges. With the rapid advancement of science and technology in China, and in order to mitigate the losses—both human and material—that floods inflict on the nation and its people, there is a growing need for sophisticated flow‑measurement techniques and instruments capable of delivering accurate measurements in a short time. Radar‑based flow measurement has gained widespread recognition within the hydrological community, and a variety of radar‑based flow‑measuring devices have been developed, enabling automated determination of discharge in small and medium-sized rivers.

　　The real-time monitoring sensor system comprises a flow meter, a water level gauge, and a flow meter. The sensors are installed along the riverbank to monitor water volume, flow velocity, and water level. They collect data and transmit it via a serial port to a Remote Terminal Unit (RTU). The RTU is equipped with a communication module and uses a cellular network to upload the data to a server platform. This data transmission terminal offers strong real-time performance, high data‑collection efficiency, and the capability for scheduled, online, automated data acquisition; its data‑acquisition interface fully meets the requirements of its intended applications.

　　Radar-based river‑channel flow monitoring consists of a radar current meter, a radar water level gauge, and a flow‑calculation terminal. The radar open‑channel flow‑measurement system is grounded in the theory of uniform flow in hydraulic open channels and employs radar waves to non‑contactly and simultaneously measure both the water surface elevation and the surface velocity at a cross section. After computing the surface velocity, the system derives the mean cross‑sectional velocity and then calculates the cross‑sectional discharge and volume using the conventional velocity‑area method. High‑precision radar current meters enable non‑contact velocity measurement, unaffected by sediment or floating debris. They are suitable for flow measurement in typical rivers and channels, particularly under conditions of high flood levels, swift currents, high sediment loads, and severe pollution.

　　By strengthening the ecosystem River flow monitoring Online monitoring and real-time management. Leveraging next-generation intelligent technologies to accelerate the development of smart water conservancy, we will establish or upgrade intelligent reservoir‑operation capabilities, select reservoirs with year‑round or multi‑year regulation, and identify rivers whose ecological functions can be improved or restored in the near term. Pilot projects for smart reservoir management and dispatch will be launched, accompanied by ecological scheduling, to continuously enhance the assurance of ecological flows downstream of reservoirs and in associated rivers and lakes.