| Shrnutí: | A micro-pulse lidar system incorporating differential absorption lidar (DIAL) and coherent Doppler wind lidar (CDWL) is proposed and demonstrated. Due to the high signal-to-noise ratio (SNR) of the superconducting nanowire single-photon detector (SNSPD), the DIAL channel achieves high sensitivity in CO<sub>2</sub> measurement. Meanwhile, the CDWL channel is used to obtain the horizontal wind field. In the process of the optimization and calibration of the DIAL receiver, specifically, mode scrambling and temperature control of the connecting fiber between the telescope and the SNSPD enhance the stability and robustness of the system. Horizontal scanning of the CO<sub>2</sub> concentration and the wind field is carried out in a 6 km range over a scanning span of 60° with a radial resolution of 150 m and 15 s. The results show that the hybrid lidar system captures the spatial distribution of CO<sub>2</sub> concentration and the wind field simultaneously. The horizontal net CO<sub>2</sub> flux in a radius of 6 km is estimated by integrating the CO<sub>2</sub> concentration and the wind transport vector, indicating different characteristics of horizontal net CO<sub>2</sub> fluxes in an industrial area, a university campus, and a park. During most of the experiment, CO<sub>2</sub> flux remained positive in the industrial area, but balances fell to nearly zero on the campus and in the park. The horizontal net fluxes averaged over 24 h in the three areas are 3.5 × 10<sup>5</sup> ppm·m<sup>2</sup>·s<sup>−1</sup>, 0.7 × 10<sup>5</sup> ppm·m<sup>2</sup>·s<sup>−1</sup>, and 0.1 × 10<sup>5</sup> ppm·m<sup>2</sup>·s<sup>−</sup><sup>1</sup>.
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