种子流失与迁移的人工降雨模拟试验方法研究

通过室内多组人工降雨模拟试验,探讨了适合于研究坡面种子流失与迁移的种子布设试验方法.结果表明,在常规人工降雨模拟试验方法的基础上,主要需加强以下方面:(1)供试种子要能代表研究区的主要物种及不同的形态特征;(2)鉴于种子的流失主要发生在土壤表层,种子适宜布设在土壤表面;(3)染色种子以区分土壤本身携带的种子;(4)每个物种的种子定点且物种间错位布设,以准确测定种子在坡面上的迁移距离;(5)种子的布设数量不宜过多,以免影响坡面糙度;(6)将大种子布设在种子布设区域的最下端以避免大种子对径流的影响.

Method of Rainfall Simulation Experiment for Seed Loss and Displacement

The appropriate experiment method for researches on seed loss and displacement is probed through several rainfall simulation experiments on loess incline. Based on the conventional method of simulated rainfall experiment,the following aspects need to be stressed:(1) Seeds for experiment should represent the main species and different shapes in the study area. (2) Seeds should be placed on soil surface as seed loss mainly occurs on the soil surface. (3) Seeds need to be dyed to distinguish the original seeds in soil. (4) Seeds of each species should be placed in a definite location and misplaced among species in order to accurately measure the distance of seed movement. (5) The amount of seeds placed in experiment should not be too much because this way influences soil surface roughness. (6) It is better for the big seeds to be placed in the bottom of seed placement area to avoid its effect on runoff path.