A video camera recording method for measuring terminal velocity of seed dispersal by wind
A video camera recording method for measuring terminal velocity of seed dispersal by wind
复制标题
一种测量风散种子终速度的摄像机记录方法
DOI：
10.1007/s11676-019-01092-8
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发表时间：
2020-01-07
影响因子：
3
通讯作者：
Zhou, Quanlai
中科院分区：
文献类型：
--
作者：
Liu, Minghu;Xin, Zhiming;Zhou, Quanlai
准确、简便的方法是测定种子风抛终端速度的关键。现有方法产生的系统误差和随机误差降低了种子终端速度测定的准确性和方便性。利用摄像机以50帧/秒的速度记录了41种具有8种附属结构和7种空气动力学行为的风载种子在沉降塔中的下落过程。通过Quick Time Player分析视频以确定种子加速高度、加速时间和终端速度。结果表明，随着翼载的增加，飞机的加速高度、加速时间、终端速度以及终端速度与下降速度之差（DTD）均增大。与滴入法相比，摄像法消除了加速度的影响，并对种子的终端速度进行了修正。为了准确测量不同种子的末端速度，根据翼载确定了种子的释放高度。该方法具有设备便宜、精度高、观测方便、操作简单等优点，可用于测定风抛种子的终端速度，为探索种子的抛撒过程提供了一种很有前途的方法。
An accurate and convenient method is essential for measuring the terminal velocity of seeds dispersed by wind. Systematic and random errors produced by existing methods lower the accuracy and convenience in determining seed terminal velocity. In this study, a video camera was used to record the falling process of forty-one species of wind-borne seed with eight appendage structures and seven aerodynamic behaviors in a settling tower at a speed of 50 frames per second (fps). The videos were analyzed by Quick Time Player to determine seed acceleration height, acceleration time, and terminal velocity. The results showed that acceleration height and time, terminal velocity, and the difference between terminal velocity and descent velocity (DTD) increased with wing loading. Compared with dropping methods, the camera recording method eliminated the effect of acceleration and corrected seed terminal velocity. Based on wing loading, release heights were determined for accurate measurement of terminal velocity of different seeds. This method, due to its inexpensive equipment, high accuracy, easy observation and operation, can be applied to measure the terminal velocity of wind dispersed seeds, and provides a promising method in exploring the dispersal process of seeds.