The 24th IAHR-APD Congress (24th IAHR-APD Congress)

326 / 2024-02-29 16:15:48

Application of unmanned aerial hyperspectral remote sensing for chlorophyll a monitoring in typical rivers

hyperspectral remote sensing,chlorophyll a,Unmanned aerial vehicle (UAV),Sihe River

In recent years, with the rapid development of China's social and economic development, rivers, lakes, reservoirs and other water bodies appear certain water environment problems. Conventional investigation methods based on monitoring stations are deficient in timeliness and spatial distribution, which could be improved to a certain extent by using hyperspectral remote sensing techniques.

    In this paper, Sihe River, a tributary of Han River, is selected as the study area, the hyperspectral sensor carried by the unmanned aerial vehicle (UAV) is applied to collect the spectral reflectance image of Si River to analyze the relationship between the faceted spectral reflectance data collected by UAV and the synchronized chlorophyll a concentration. The reflectance spectral of Sihe River at the sampling point were normalized using its band reflectance in the visible range (450-800 nm) to eliminate systematic errors during data collection with different sorties of UAVs, and the regression analyses were performed using the ratio of the reflectance of the two bands, 676 nm and 706 nm  and the chlorophyll a concentration at the sampling point  to establish the relationship to inverse of river water body chlorophyll on the area.

    The preliminary experiment shows that the chlorophyll a inversion model using hyperspectral remote sensing data has high reliability and practicability, which indicates the feasibility of using hyperspectral remote sensing data to monitor the chlorophyll a information of the river water body, and can be used as an effective supplement to the conventional investigation methods based on the monitoring stations, and can provide technical support and reference for the environmental monitoring in water quality monitoring.