State Key Laboratory of Earth Surface Processes and Resource Ecology, MOE Engineering Research Center of Desertification and Blown-sand Control, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China 在期刊界中查找 在百度中查找 在本站中查找
State Key Laboratory of Earth Surface Processes and Resource Ecology, MOE Engineering Research Center of Desertification and Blown-sand Control, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China 在期刊界中查找 在百度中查找 在本站中查找
State Key Laboratory of Earth Surface Processes and Resource Ecology, MOE Engineering Research Center of Desertification and Blown-sand Control, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China 在期刊界中查找 在百度中查找 在本站中查找
State Key Laboratory of Earth Surface Processes and Resource Ecology, MOE Engineering Research Center of Desertification and Blown-sand Control, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China 在期刊界中查找 在百度中查找 在本站中查找
State Key Laboratory of Earth Surface Processes and Resource Ecology, MOE Engineering Research Center of Desertification and Blown-sand Control, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China 在期刊界中查找 在百度中查找 在本站中查找
State Key Laboratory of Earth Surface Processes and Resource Ecology, MOE Engineering Research Center of Desertification and Blown-sand Control, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China 在期刊界中查找 在百度中查找 在本站中查找
[Objective] The characteristics of wind velocity pulsation and its relation to the average wind velocity and friction wind velocity were studied to reveal the rule of the wind velocity pulsation above grassland.[Methods] A sonic anemometer was used to observe the near surface wind velocity above the grassland.[Results] The near surface wind velocity had obvious pulsating characteristics, and there was a significant positive linear correlation between the pulsation intensity and the average wind velocity. The turbulence distribution was very scattered at a low wind velocity but tended to concentrate with the increase of the average wind velocity. The turbulence intensity at the peak of its probability distribution curve was 0.23 under a wind velocity ranging from 2 to 14 m/s. There was no correlation between the friction wind velocity and the instantaneous wind velocity. The friction wind velocity was positively and linearly correlated with the average wind speed at 1 s time intervals, but the fluctuation of the calculated results was still obvious because of wind velocity pulsation. At 1 min time intervals, the influence of wind pulsation on friction velocity was approximately 10%, and the linear correlation between friction wind velocity and average wind speed was extremely significant.[Conclusion] The wind velocity pulsation has a great influence on the calculation of the friction wind velocity. Using the average wind velocity at 1 s or 1 min time intervals can effectively reduce this influence.
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