marine ecosystem, phytoplankton, marine gross primary productivity, fluorescence kinetics, rapid measurement, in situ sensing, Naval architecture. Shipbuilding. Marine engineering, VM1-989

Marine gross primary productivity(GPP) constitutes a fundamental element of the biological matter cycle and energy flow within the marine ecosystem, serving as a key indicator for assessing the sate of marine ecological environment. Traditional methods of measuring GPP are often laborious, with long measurement period and poor immediacy. To address the pressing need for expeditious monitoring of marine GPP in ecological surveys and carbon sink assessment, we explored multi-wavelength variable light pulse-induced fluorescence kinetic technology. This approach leverages chlorophyll fluorescence as a probe of phytoplankton photosynthetic activity and culminated in the development of an in-situ sensor. Subsequently, we applied this sensor in trials across the Arctic, Yellow Sea, Bohai Sea, and South China Sea. The resulting spatial distribution of GPP across these regions has yielded extensive real-time observational data, contributing substantially to the monitoring and scientific research of the marine ecological environment. Sea trials outcomes demonstrate that the multi-band variable light pulse-induced fluorescence kinetic technology can rapidly and accurately estimate GPP, offering notable advantages such as speed, accuracy, stability, and reliability in measurement. This ultimately provides an advanced technical resource for marine ecological investigations and carbon sink assessments.