醉马草种子风传扩散特性

Study on the Characteristics of Wind Propagation and Dispersal of Achnatherum inebrians seeds

【目的】研究醉马草种子风传扩散特性。【方法】以草原毒害草醉马草(Achnatherum inebrians)为材料,测定种子在静止空气中的垂直沉降时间,在不同风速下的水平移动距离,分析沉降时间与移动距离之间的相关性;测定自然风力条件下种子扩散距离并建立种子扩散距离模型,分析风力对醉马草种子扩散的影响。【结果】醉马草有芒种子的沉降速度显著小于去芒种子;种子水平移动距离随风速的增加而增加,且芒对水平移动距离无影响。在自然风力作用下,高、中、低植株扩散距离为0~220 cm,种子二次扩散距离范围为0~18 cm。在3种株高中,中植株的拟合效果最好,其模型为:Y_(中)=0.00288+0.0065 X-0.00004246 X^(2)+0.000000062284 X^(3)。【结论】附属物芒、高风速都促进醉马草种子风媒扩散。醉马草种子在风传扩散中属于短距离扩散。

【Objective】Study on the Characteristics of Wind Propagation and Dispersal of Achnatherum inebrians seeds.【Method】Taking the poisonous grassland grass Achnatherum inebrians as the research material,the vertical settling time of seeds in still air and the horizontal moving distance under different wind speeds were measured,and the correlation between settling time and moving distance was analyzed;The seed dispersal distance under natural wind was measured and the seed dispersal distance model was established to explore the effect of wind on seed dispersal of Achnatherum inebrians.【Result】The settling velocity of the awned seeds of Achnatherum inebrians was significantly lower than that of the no-awned seeds;The horizontal moving distance of seeds increased with the increase of wind speed,and the awned had no effect on the horizontal moving distance.Under the action of natural wind,the dispersal distance of high,middle and low plants was 0-220 cm,and the secondary dispersal distance of seeds was 0-18 cm.Among the three plants,the fitting effects of middle and high plants were the best.The model was:Y_(middle)=0.002,88+0.006,5X-0.000,042,46X^(2)+0.000,000,062,284X^(3).【Conclusion】The awned and high winds speeds promote the wind dispersal of Achnatherum inebrians seeds.Achnatherum inebrians seeds belong to short-distance dispersal in wind dispersal.